TUN-5989: Add in-memory otlp exporter

vendor/go.opentelemetry.io/contrib/propagators/Jaeger/context.go

@@ -0,0 +1,41 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package jaeger
+
+import "context"
+
+type jaegerKeyType int
+
+const (
+	debugKey jaegerKeyType = iota
+)
+
+// withDebug returns a copy of parent with debug set as the debug flag value .
+func withDebug(parent context.Context, debug bool) context.Context {
+	return context.WithValue(parent, debugKey, debug)
+}
+
+// debugFromContext returns the debug value stored in ctx.
+//
+// If no debug value is stored in ctx false is returned.
+func debugFromContext(ctx context.Context) bool {
+	if ctx == nil {
+		return false
+	}
+	if debug, ok := ctx.Value(debugKey).(bool); ok {
+		return debug
+	}
+	return false
+}

vendor/go.opentelemetry.io/contrib/propagators/Jaeger/doc.go

@@ -0,0 +1,17 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This package implements the Jaeger propagator specification as defined
+// at https://www.jaegertracing.io/docs/1.18/client-libraries/#propagation-format
+package jaeger // import "go.opentelemetry.io/contrib/propagators/jaeger"

vendor/go.opentelemetry.io/contrib/propagators/Jaeger/jaeger_propagator.go

@@ -0,0 +1,161 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package jaeger
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/trace"
+)
+
+const (
+	jaegerHeader        = "uber-trace-id"
+	separator           = ":"
+	traceID64bitsWidth  = 64 / 4
+	traceID128bitsWidth = 128 / 4
+	spanIDWidth         = 64 / 4
+
+	traceIDPadding = "0000000000000000"
+
+	flagsDebug      = 0x02
+	flagsSampled    = 0x01
+	flagsNotSampled = 0x00
+
+	deprecatedParentSpanID = "0"
+)
+
+var (
+	empty = trace.SpanContext{}
+
+	errMalformedTraceContextVal = errors.New("header value of uber-trace-id should contain four different part separated by : ")
+	errInvalidTraceIDLength     = errors.New("invalid trace id length, must be either 16 or 32")
+	errMalformedTraceID         = errors.New("cannot decode trace id from header, should be a string of hex, lowercase trace id can't be all zero")
+	errInvalidSpanIDLength      = errors.New("invalid span id length, must be 16")
+	errMalformedSpanID          = errors.New("cannot decode span id from header, should be a string of hex, lowercase span id can't be all zero")
+	errMalformedFlag            = errors.New("cannot decode flag")
+)
+
+// Jaeger propagator serializes SpanContext to/from Jaeger Headers
+//
+// Jaeger format:
+//
+// uber-trace-id: {trace-id}:{span-id}:{parent-span-id}:{flags}
+type Jaeger struct{}
+
+var _ propagation.TextMapPropagator = &Jaeger{}
+
+// Inject injects a context to the carrier following jaeger format.
+// The parent span ID is set to an dummy parent span id as the most implementations do.
+func (jaeger Jaeger) Inject(ctx context.Context, carrier propagation.TextMapCarrier) {
+	sc := trace.SpanFromContext(ctx).SpanContext()
+	headers := []string{}
+	if !sc.TraceID().IsValid() || !sc.SpanID().IsValid() {
+		return
+	}
+	headers = append(headers, sc.TraceID().String(), sc.SpanID().String(), deprecatedParentSpanID)
+	if debugFromContext(ctx) {
+		headers = append(headers, fmt.Sprintf("%x", flagsDebug|flagsSampled))
+	} else if sc.IsSampled() {
+		headers = append(headers, fmt.Sprintf("%x", flagsSampled))
+	} else {
+		headers = append(headers, fmt.Sprintf("%x", flagsNotSampled))
+	}
+
+	carrier.Set(jaegerHeader, strings.Join(headers, separator))
+}
+
+// Extract extracts a context from the carrier if it contains Jaeger headers.
+func (jaeger Jaeger) Extract(ctx context.Context, carrier propagation.TextMapCarrier) context.Context {
+	// extract tracing information
+	if h := carrier.Get(jaegerHeader); h != "" {
+		ctx, sc, err := extract(ctx, h)
+		if err == nil && sc.IsValid() {
+			return trace.ContextWithRemoteSpanContext(ctx, sc)
+		}
+	}
+
+	return ctx
+}
+
+func extract(ctx context.Context, headerVal string) (context.Context, trace.SpanContext, error) {
+	var (
+		scc = trace.SpanContextConfig{}
+		err error
+	)
+
+	parts := strings.Split(headerVal, separator)
+	if len(parts) != 4 {
+		return ctx, empty, errMalformedTraceContextVal
+	}
+
+	// extract trace ID
+	if parts[0] != "" {
+		id := parts[0]
+		if len(id) != traceID128bitsWidth && len(id) != traceID64bitsWidth {
+			return ctx, empty, errInvalidTraceIDLength
+		}
+		// padding when length is 16
+		if len(id) == traceID64bitsWidth {
+			id = traceIDPadding + id
+		}
+		scc.TraceID, err = trace.TraceIDFromHex(id)
+		if err != nil {
+			return ctx, empty, errMalformedTraceID
+		}
+	}
+
+	// extract span ID
+	if parts[1] != "" {
+		id := parts[1]
+		if len(id) != spanIDWidth {
+			return ctx, empty, errInvalidSpanIDLength
+		}
+		scc.SpanID, err = trace.SpanIDFromHex(id)
+		if err != nil {
+			return ctx, empty, errMalformedSpanID
+		}
+	}
+
+	// skip third part as it is deprecated
+
+	// extract flag
+	if parts[3] != "" {
+		flagStr := parts[3]
+		flag, err := strconv.ParseInt(flagStr, 16, 64)
+		if err != nil {
+			return ctx, empty, errMalformedFlag
+		}
+		if flag&flagsSampled == flagsSampled {
+			// if sample bit is set, we check if debug bit is also set
+			if flag&flagsDebug == flagsDebug {
+				scc.TraceFlags |= trace.FlagsSampled
+				ctx = withDebug(ctx, true)
+			} else {
+				scc.TraceFlags |= trace.FlagsSampled
+			}
+		}
+		// ignore other bit, including firehose since we don't have corresponding flag in trace context.
+	}
+	return ctx, trace.NewSpanContext(scc), nil
+}
+
+func (jaeger Jaeger) Fields() []string {
+	return []string{jaegerHeader}
+}

vendor/go.opentelemetry.io/contrib/propagators/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
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+      the Work or Derivative Works thereof, You may choose to offer,
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+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
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+      of your accepting any such warranty or additional liability.
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+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
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vendor/go.opentelemetry.io/otel/.gitattributes

@@ -0,0 +1,3 @@
+* text=auto eol=lf
+*.{cmd,[cC][mM][dD]} text eol=crlf
+*.{bat,[bB][aA][tT]} text eol=crlf

vendor/go.opentelemetry.io/otel/.gitignore

@@ -0,0 +1,20 @@
+.DS_Store
+Thumbs.db
+
+.tools/
+.idea/
+.vscode/
+*.iml
+*.so
+coverage.*
+
+gen/
+
+/example/fib/fib
+/example/jaeger/jaeger
+/example/namedtracer/namedtracer
+/example/opencensus/opencensus
+/example/passthrough/passthrough
+/example/prometheus/prometheus
+/example/zipkin/zipkin
+/example/otel-collector/otel-collector

vendor/go.opentelemetry.io/otel/.gitmodules

@@ -0,0 +1,3 @@
+[submodule "opentelemetry-proto"]
+	path = exporters/otlp/internal/opentelemetry-proto
+	url = https://github.com/open-telemetry/opentelemetry-proto

vendor/go.opentelemetry.io/otel/.golangci.yml

@@ -0,0 +1,47 @@
+# See https://github.com/golangci/golangci-lint#config-file
+run:
+  issues-exit-code: 1 #Default
+  tests: true #Default
+
+linters:
+  # Disable everything by default so upgrades to not include new "default
+  # enabled" linters.
+  disable-all: true
+  # Specifically enable linters we want to use.
+  enable:
+    - deadcode
+    - errcheck
+    - gofmt
+    - goimports
+    - gosimple
+    - govet
+    - ineffassign
+    - misspell
+    - revive
+    - staticcheck
+    - structcheck
+    - typecheck
+    - unused
+    - varcheck
+
+
+issues:
+  exclude-rules:
+    # helpers in tests often (rightfully) pass a *testing.T as their first argument
+    - path: _test\.go
+      text: "context.Context should be the first parameter of a function"
+      linters:
+        - revive
+    # Yes, they are, but it's okay in a test
+    - path: _test\.go
+      text: "exported func.*returns unexported type.*which can be annoying to use"
+      linters:
+        - revive
+
+linters-settings:
+  misspell:
+    locale: US
+    ignore-words:
+      - cancelled
+  goimports:
+    local-prefixes: go.opentelemetry.io

vendor/go.opentelemetry.io/otel/.markdown-link.json

@@ -0,0 +1,20 @@
+{
+    "ignorePatterns": [
+        {
+            "pattern": "^http(s)?://localhost"
+        }
+    ],
+    "replacementPatterns": [
+        {
+            "pattern": "^/registry",
+            "replacement": "https://opentelemetry.io/registry"
+        },
+        {
+            "pattern": "^/docs/",
+            "replacement": "https://opentelemetry.io/docs/"
+        }
+    ],
+    "retryOn429": true,
+    "retryCount": 5,
+    "fallbackRetryDelay": "30s"
+}

vendor/go.opentelemetry.io/otel/.markdownlint.yaml

@@ -0,0 +1,29 @@
+# Default state for all rules
+default: true
+
+# ul-style
+MD004: false
+
+# hard-tabs
+MD010: false
+
+# line-length
+MD013: false
+
+# no-duplicate-header
+MD024:
+  siblings_only: true
+
+#single-title
+MD025: false
+
+# ol-prefix
+MD029:
+  style: ordered
+
+# no-inline-html
+MD033: false
+
+# fenced-code-language
+MD040: false
+

vendor/go.opentelemetry.io/otel/CODEOWNERS

@@ -0,0 +1,17 @@
+#####################################################
+#
+# List of approvers for this repository
+#
+#####################################################
+#
+# Learn about membership in OpenTelemetry community:
+#  https://github.com/open-telemetry/community/blob/main/community-membership.md
+#
+#
+# Learn about CODEOWNERS file format:
+#  https://help.github.com/en/articles/about-code-owners
+#
+
+* @jmacd @MrAlias @Aneurysm9 @evantorrie @XSAM @dashpole @paivagustavo @MadVikingGod @pellared @hanyuancheung
+
+CODEOWNERS @MrAlias @Aneurysm9 @MadVikingGod

vendor/go.opentelemetry.io/otel/CONTRIBUTING.md

@@ -0,0 +1,522 @@
+# Contributing to opentelemetry-go
+
+The Go special interest group (SIG) meets regularly. See the
+OpenTelemetry
+[community](https://github.com/open-telemetry/community#golang-sdk)
+repo for information on this and other language SIGs.
+
+See the [public meeting
+notes](https://docs.google.com/document/d/1A63zSWX0x2CyCK_LoNhmQC4rqhLpYXJzXbEPDUQ2n6w/edit#heading=h.9tngw7jdwd6b)
+for a summary description of past meetings. To request edit access,
+join the meeting or get in touch on
+[Slack](https://cloud-native.slack.com/archives/C01NPAXACKT).
+
+## Development
+
+You can view and edit the source code by cloning this repository:
+
+```sh
+git clone https://github.com/open-telemetry/opentelemetry-go.git
+```
+
+Run `make test` to run the tests instead of `go test`.
+
+There are some generated files checked into the repo. To make sure
+that the generated files are up-to-date, run `make` (or `make
+precommit` - the `precommit` target is the default).
+
+The `precommit` target also fixes the formatting of the code and
+checks the status of the go module files.
+
+If after running `make precommit` the output of `git status` contains
+`nothing to commit, working tree clean` then it means that everything
+is up-to-date and properly formatted.
+
+## Pull Requests
+
+### How to Send Pull Requests
+
+Everyone is welcome to contribute code to `opentelemetry-go` via
+GitHub pull requests (PRs).
+
+To create a new PR, fork the project in GitHub and clone the upstream
+repo:
+
+```sh
+go get -d go.opentelemetry.io/otel
+```
+
+(This may print some warning about "build constraints exclude all Go
+files", just ignore it.)
+
+This will put the project in `${GOPATH}/src/go.opentelemetry.io/otel`. You
+can alternatively use `git` directly with:
+
+```sh
+git clone https://github.com/open-telemetry/opentelemetry-go
+```
+
+(Note that `git clone` is *not* using the `go.opentelemetry.io/otel` name -
+that name is a kind of a redirector to GitHub that `go get` can
+understand, but `git` does not.)
+
+This would put the project in the `opentelemetry-go` directory in
+current working directory.
+
+Enter the newly created directory and add your fork as a new remote:
+
+```sh
+git remote add <YOUR_FORK> git@github.com:<YOUR_GITHUB_USERNAME>/opentelemetry-go
+```
+
+Check out a new branch, make modifications, run linters and tests, update
+`CHANGELOG.md`, and push the branch to your fork:
+
+```sh
+git checkout -b <YOUR_BRANCH_NAME>
+# edit files
+# update changelog
+make precommit
+git add -p
+git commit
+git push <YOUR_FORK> <YOUR_BRANCH_NAME>
+```
+
+Open a pull request against the main `opentelemetry-go` repo. Be sure to add the pull
+request ID to the entry you added to `CHANGELOG.md`.
+
+### How to Receive Comments
+
+* If the PR is not ready for review, please put `[WIP]` in the title,
+  tag it as `work-in-progress`, or mark it as
+  [`draft`](https://github.blog/2019-02-14-introducing-draft-pull-requests/).
+* Make sure CLA is signed and CI is clear.
+
+### How to Get PRs Merged
+
+A PR is considered to be **ready to merge** when:
+
+* It has received two approvals from Collaborators/Maintainers (at
+  different companies). This is not enforced through technical means
+  and a PR may be **ready to merge** with a single approval if the change
+  and its approach have been discussed and consensus reached.
+* Feedback has been addressed.
+* Any substantive changes to your PR will require that you clear any prior
+  Approval reviews, this includes changes resulting from other feedback. Unless
+  the approver explicitly stated that their approval will persist across
+  changes it should be assumed that the PR needs their review again. Other
+  project members (e.g. approvers, maintainers) can help with this if there are
+  any questions or if you forget to clear reviews.
+* It has been open for review for at least one working day. This gives
+  people reasonable time to review.
+* Trivial changes (typo, cosmetic, doc, etc.) do not have to wait for
+  one day and may be merged with a single Maintainer's approval.
+* `CHANGELOG.md` has been updated to reflect what has been
+  added, changed, removed, or fixed.
+* `README.md` has been updated if necessary.
+* Urgent fix can take exception as long as it has been actively
+  communicated.
+
+Any Maintainer can merge the PR once it is **ready to merge**.
+
+## Design Choices
+
+As with other OpenTelemetry clients, opentelemetry-go follows the
+[opentelemetry-specification](https://github.com/open-telemetry/opentelemetry-specification).
+
+It's especially valuable to read through the [library
+guidelines](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/library-guidelines.md).
+
+### Focus on Capabilities, Not Structure Compliance
+
+OpenTelemetry is an evolving specification, one where the desires and
+use cases are clear, but the method to satisfy those uses cases are
+not.
+
+As such, Contributions should provide functionality and behavior that
+conforms to the specification, but the interface and structure is
+flexible.
+
+It is preferable to have contributions follow the idioms of the
+language rather than conform to specific API names or argument
+patterns in the spec.
+
+For a deeper discussion, see
+[this](https://github.com/open-telemetry/opentelemetry-specification/issues/165).
+
+## Documentation
+
+Each non-example Go Module should have its own `README.md` containing:
+
+- A pkg.go.dev badge which can be generated [here](https://pkg.go.dev/badge/).
+- Brief description.
+- Installation instructions (and requirements if applicable).
+- Hyperlink to an example. Depending on the component the example can be:
+  - An `example_test.go` like [here](exporters/stdout/stdouttrace/example_test.go).
+  - A sample Go application with its own `README.md`, like [here](example/zipkin).
+- Additional documentation sections such us:
+  - Configuration,
+  - Contributing,
+  - References.
+
+[Here](exporters/jaeger/README.md) is an example of a concise `README.md`.
+
+Moreover, it should be possible to navigate to any `README.md` from the
+root `README.md`.
+
+## Style Guide
+
+One of the primary goals of this project is that it is actually used by
+developers. With this goal in mind the project strives to build
+user-friendly and idiomatic Go code adhering to the Go community's best
+practices.
+
+For a non-comprehensive but foundational overview of these best practices
+the [Effective Go](https://golang.org/doc/effective_go.html) documentation
+is an excellent starting place.
+
+As a convenience for developers building this project the `make precommit`
+will format, lint, validate, and in some cases fix the changes you plan to
+submit. This check will need to pass for your changes to be able to be
+merged.
+
+In addition to idiomatic Go, the project has adopted certain standards for
+implementations of common patterns. These standards should be followed as a
+default, and if they are not followed documentation needs to be included as
+to the reasons why.
+
+### Configuration
+
+When creating an instantiation function for a complex `type T struct`, it is
+useful to allow variable number of options to be applied. However, the strong
+type system of Go restricts the function design options. There are a few ways
+to solve this problem, but we have landed on the following design.
+
+#### `config`
+
+Configuration should be held in a `struct` named `config`, or prefixed with
+specific type name this Configuration applies to if there are multiple
+`config` in the package. This type must contain configuration options.
+
+```go
+// config contains configuration options for a thing.
+type config struct {
+	// options ...
+}
+```
+
+In general the `config` type will not need to be used externally to the
+package and should be unexported. If, however, it is expected that the user
+will likely want to build custom options for the configuration, the `config`
+should be exported. Please, include in the documentation for the `config`
+how the user can extend the configuration.
+
+It is important that internal `config` are not shared across package boundaries.
+Meaning a `config` from one package should not be directly used by another. The
+one exception is the API packages.  The configs from the base API, eg.
+`go.opentelemetry.io/otel/trace.TracerConfig` and
+`go.opentelemetry.io/otel/metric.InstrumentConfig`, are intended to be consumed
+by the SDK therefor it is expected that these are exported.
+
+When a config is exported we want to maintain forward and backward
+compatibility, to achieve this no fields should be exported but should
+instead be accessed by methods.
+
+Optionally, it is common to include a `newConfig` function (with the same
+naming scheme). This function wraps any defaults setting and looping over
+all options to create a configured `config`.
+
+```go
+// newConfig returns an appropriately configured config.
+func newConfig(options ...Option) config {
+	// Set default values for config.
+	config := config{/* […] */}
+	for _, option := range options {
+		config = option.apply(config)
+	}
+	// Preform any validation here.
+	return config
+}
+```
+
+If validation of the `config` options is also preformed this can return an
+error as well that is expected to be handled by the instantiation function
+or propagated to the user.
+
+Given the design goal of not having the user need to work with the `config`,
+the `newConfig` function should also be unexported.
+
+#### `Option`
+
+To set the value of the options a `config` contains, a corresponding
+`Option` interface type should be used.
+
+```go
+type Option interface {
+	apply(config) config
+}
+```
+
+Having `apply` unexported makes sure that it will not be used externally.
+Moreover, the interface becomes sealed so the user cannot easily implement
+the interface on its own.
+
+The `apply` method should return a modified version of the passed config.
+This approach, instead of passing a pointer, is used to prevent the config from being allocated to the heap.
+
+The name of the interface should be prefixed in the same way the
+corresponding `config` is (if at all).
+
+#### Options
+
+All user configurable options for a `config` must have a related unexported
+implementation of the `Option` interface and an exported configuration
+function that wraps this implementation.
+
+The wrapping function name should be prefixed with `With*` (or in the
+special case of a boolean options `Without*`) and should have the following
+function signature.
+
+```go
+func With*(…) Option { … }
+```
+
+##### `bool` Options
+
+```go
+type defaultFalseOption bool
+
+func (o defaultFalseOption) apply(c config) config {
+	c.Bool = bool(o)
+    return c
+}
+
+// WithOption sets a T to have an option included.
+func WithOption() Option {
+	return defaultFalseOption(true)
+}
+```
+
+```go
+type defaultTrueOption bool
+
+func (o defaultTrueOption) apply(c config) config {
+	c.Bool = bool(o)
+    return c
+}
+
+// WithoutOption sets a T to have Bool option excluded.
+func WithoutOption() Option {
+	return defaultTrueOption(false)
+}
+```
+
+##### Declared Type Options
+
+```go
+type myTypeOption struct {
+	MyType MyType
+}
+
+func (o myTypeOption) apply(c config) config {
+	c.MyType = o.MyType
+    return c
+}
+
+// WithMyType sets T to have include MyType.
+func WithMyType(t MyType) Option {
+	return myTypeOption{t}
+}
+```
+
+##### Functional Options
+
+```go
+type optionFunc func(config) config
+
+func (fn optionFunc) apply(c config) config {
+	return fn(c)
+}
+
+// WithMyType sets t as MyType.
+func WithMyType(t MyType) Option {
+	return optionFunc(func(c config) config {
+		c.MyType = t
+        return c
+	})
+}
+```
+
+#### Instantiation
+
+Using this configuration pattern to configure instantiation with a `NewT`
+function.
+
+```go
+func NewT(options ...Option) T {…}
+```
+
+Any required parameters can be declared before the variadic `options`.
+
+#### Dealing with Overlap
+
+Sometimes there are multiple complex `struct` that share common
+configuration and also have distinct configuration. To avoid repeated
+portions of `config`s, a common `config` can be used with the union of
+options being handled with the `Option` interface.
+
+For example.
+
+```go
+// config holds options for all animals.
+type config struct {
+	Weight      float64
+	Color       string
+	MaxAltitude float64
+}
+
+// DogOption apply Dog specific options.
+type DogOption interface {
+	applyDog(config) config
+}
+
+// BirdOption apply Bird specific options.
+type BirdOption interface {
+	applyBird(config) config
+}
+
+// Option apply options for all animals.
+type Option interface {
+	BirdOption
+	DogOption
+}
+
+type weightOption float64
+
+func (o weightOption) applyDog(c config) config {
+	c.Weight = float64(o)
+	return c
+}
+
+func (o weightOption) applyBird(c config) config {
+	c.Weight = float64(o)
+	return c
+}
+
+func WithWeight(w float64) Option { return weightOption(w) }
+
+type furColorOption string
+
+func (o furColorOption) applyDog(c config) config {
+	c.Color = string(o)
+	return c
+}
+
+func WithFurColor(c string) DogOption { return furColorOption(c) }
+
+type maxAltitudeOption float64
+
+func (o maxAltitudeOption) applyBird(c config) config {
+	c.MaxAltitude = float64(o)
+	return c
+}
+
+func WithMaxAltitude(a float64) BirdOption { return maxAltitudeOption(a) }
+
+func NewDog(name string, o ...DogOption) Dog    {…}
+func NewBird(name string, o ...BirdOption) Bird {…}
+```
+
+### Interfaces
+
+To allow other developers to better comprehend the code, it is important
+to ensure it is sufficiently documented. One simple measure that contributes
+to this aim is self-documenting by naming method parameters. Therefore,
+where appropriate, methods of every exported interface type should have
+their parameters appropriately named.
+
+#### Interface Stability
+
+All exported stable interfaces that include the following warning in their
+doumentation are allowed to be extended with additional methods.
+
+> Warning: methods may be added to this interface in minor releases.
+
+Otherwise, stable interfaces MUST NOT be modified.
+
+If new functionality is needed for an interface that cannot be changed it MUST
+be added by including an additional interface. That added interface can be a
+simple interface for the specific functionality that you want to add or it can
+be a super-set of the original interface. For example, if you wanted to a
+`Close` method to the `Exporter` interface:
+
+```go
+type Exporter interface {
+	Export()
+}
+```
+
+A new interface, `Closer`, can be added:
+
+```go
+type Closer interface {
+	Close()
+}
+```
+
+Code that is passed the `Exporter` interface can now check to see if the passed
+value also satisfies the new interface. E.g.
+
+```go
+func caller(e Exporter) {
+	/* ... */
+	if c, ok := e.(Closer); ok {
+		c.Close()
+	}
+	/* ... */
+}
+```
+
+Alternatively, a new type that is the super-set of an `Exporter` can be created.
+
+```go
+type ClosingExporter struct {
+	Exporter
+	Close()
+}
+```
+
+This new type can be used similar to the simple interface above in that a
+passed `Exporter` type can be asserted to satisfy the `ClosingExporter` type
+and the `Close` method called.
+
+This super-set approach can be useful if there is explicit behavior that needs
+to be coupled with the original type and passed as a unified type to a new
+function, but, because of this coupling, it also limits the applicability of
+the added functionality. If there exist other interfaces where this
+functionality should be added, each one will need their own super-set
+interfaces and will duplicate the pattern. For this reason, the simple targeted
+interface that defines the specific functionality should be preferred.
+
+## Approvers and Maintainers
+
+Approvers:
+
+- [Evan Torrie](https://github.com/evantorrie), Verizon Media
+- [Josh MacDonald](https://github.com/jmacd), LightStep
+- [Sam Xie](https://github.com/XSAM), Cisco/AppDynamics
+- [David Ashpole](https://github.com/dashpole), Google
+- [Gustavo Silva Paiva](https://github.com/paivagustavo), LightStep
+- [Robert Pająk](https://github.com/pellared), Splunk
+- [Chester Cheung](https://github.com/hanyuancheung), Tencent
+
+Maintainers:
+
+- [Aaron Clawson](https://github.com/MadVikingGod), LightStep
+- [Anthony Mirabella](https://github.com/Aneurysm9), AWS
+- [Tyler Yahn](https://github.com/MrAlias), Splunk
+
+### Become an Approver or a Maintainer
+
+See the [community membership document in OpenTelemetry community
+repo](https://github.com/open-telemetry/community/blob/main/community-membership.md).

vendor/go.opentelemetry.io/otel/LICENSE

@@ -0,0 +1,201 @@
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vendor/go.opentelemetry.io/otel/Makefile

@@ -0,0 +1,209 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+TOOLS_MOD_DIR := ./internal/tools
+
+ALL_DOCS := $(shell find . -name '*.md' -type f | sort)
+ALL_GO_MOD_DIRS := $(shell find . -type f -name 'go.mod' -exec dirname {} \; | sort)
+OTEL_GO_MOD_DIRS := $(filter-out $(TOOLS_MOD_DIR), $(ALL_GO_MOD_DIRS))
+ALL_COVERAGE_MOD_DIRS := $(shell find . -type f -name 'go.mod' -exec dirname {} \; | egrep -v '^./example|^$(TOOLS_MOD_DIR)' | sort)
+
+GO = go
+TIMEOUT = 60
+
+.DEFAULT_GOAL := precommit
+
+.PHONY: precommit ci
+precommit: dependabot-generate license-check misspell go-mod-tidy golangci-lint-fix test-default
+ci: dependabot-check license-check lint vanity-import-check build test-default check-clean-work-tree test-coverage
+
+# Tools
+
+TOOLS = $(CURDIR)/.tools
+
+$(TOOLS):
+	@mkdir -p $@
+$(TOOLS)/%: | $(TOOLS)
+	cd $(TOOLS_MOD_DIR) && \
+	$(GO) build -o $@ $(PACKAGE)
+
+MULTIMOD = $(TOOLS)/multimod
+$(TOOLS)/multimod: PACKAGE=go.opentelemetry.io/build-tools/multimod
+
+SEMCONVGEN = $(TOOLS)/semconvgen
+$(TOOLS)/semconvgen: PACKAGE=go.opentelemetry.io/build-tools/semconvgen
+
+CROSSLINK = $(TOOLS)/crosslink
+$(TOOLS)/crosslink: PACKAGE=go.opentelemetry.io/otel/$(TOOLS_MOD_DIR)/crosslink
+
+DBOTCONF = $(TOOLS)/dbotconf
+$(TOOLS)/dbotconf: PACKAGE=go.opentelemetry.io/build-tools/dbotconf
+
+GOLANGCI_LINT = $(TOOLS)/golangci-lint
+$(TOOLS)/golangci-lint: PACKAGE=github.com/golangci/golangci-lint/cmd/golangci-lint
+
+MISSPELL = $(TOOLS)/misspell
+$(TOOLS)/misspell: PACKAGE=github.com/client9/misspell/cmd/misspell
+
+GOCOVMERGE = $(TOOLS)/gocovmerge
+$(TOOLS)/gocovmerge: PACKAGE=github.com/wadey/gocovmerge
+
+STRINGER = $(TOOLS)/stringer
+$(TOOLS)/stringer: PACKAGE=golang.org/x/tools/cmd/stringer
+
+PORTO = $(TOOLS)/porto
+$(TOOLS)/porto: PACKAGE=github.com/jcchavezs/porto/cmd/porto
+
+GOJQ = $(TOOLS)/gojq
+$(TOOLS)/gojq: PACKAGE=github.com/itchyny/gojq/cmd/gojq
+
+.PHONY: tools
+tools: $(CROSSLINK) $(DBOTCONF) $(GOLANGCI_LINT) $(MISSPELL) $(GOCOVMERGE) $(STRINGER) $(PORTO) $(GOJQ) $(SEMCONVGEN) $(MULTIMOD)
+
+# Build
+
+.PHONY: generate build
+
+generate: $(OTEL_GO_MOD_DIRS:%=generate/%)
+generate/%: DIR=$*
+generate/%: | $(STRINGER) $(PORTO)
+	@echo "$(GO) generate $(DIR)/..." \
+		&& cd $(DIR) \
+		&& PATH="$(TOOLS):$${PATH}" $(GO) generate ./... && $(PORTO) -w .
+
+build: generate $(OTEL_GO_MOD_DIRS:%=build/%) $(OTEL_GO_MOD_DIRS:%=build-tests/%)
+build/%: DIR=$*
+build/%:
+	@echo "$(GO) build $(DIR)/..." \
+		&& cd $(DIR) \
+		&& $(GO) build ./...
+
+build-tests/%: DIR=$*
+build-tests/%:
+	@echo "$(GO) build tests $(DIR)/..." \
+		&& cd $(DIR) \
+		&& $(GO) list ./... \
+		| grep -v third_party \
+		| xargs $(GO) test -vet=off -run xxxxxMatchNothingxxxxx >/dev/null
+
+# Tests
+
+TEST_TARGETS := test-default test-bench test-short test-verbose test-race
+.PHONY: $(TEST_TARGETS) test
+test-default test-race: ARGS=-race
+test-bench:   ARGS=-run=xxxxxMatchNothingxxxxx -test.benchtime=1ms -bench=.
+test-short:   ARGS=-short
+test-verbose: ARGS=-v -race
+$(TEST_TARGETS): test
+test: $(OTEL_GO_MOD_DIRS:%=test/%)
+test/%: DIR=$*
+test/%:
+	@echo "$(GO) test -timeout $(TIMEOUT)s $(ARGS) $(DIR)/..." \
+		&& cd $(DIR) \
+		&& $(GO) list ./... \
+		| grep -v third_party \
+		| xargs $(GO) test -timeout $(TIMEOUT)s $(ARGS)
+
+COVERAGE_MODE    = atomic
+COVERAGE_PROFILE = coverage.out
+.PHONY: test-coverage
+test-coverage: | $(GOCOVMERGE)
+	@set -e; \
+	printf "" > coverage.txt; \
+	for dir in $(ALL_COVERAGE_MOD_DIRS); do \
+	  echo "$(GO) test -coverpkg=go.opentelemetry.io/otel/... -covermode=$(COVERAGE_MODE) -coverprofile="$(COVERAGE_PROFILE)" $${dir}/..."; \
+	  (cd "$${dir}" && \
+	    $(GO) list ./... \
+	    | grep -v third_party \
+	    | xargs $(GO) test -coverpkg=./... -covermode=$(COVERAGE_MODE) -coverprofile="$(COVERAGE_PROFILE)" && \
+	  $(GO) tool cover -html=coverage.out -o coverage.html); \
+	done; \
+	$(GOCOVMERGE) $$(find . -name coverage.out) > coverage.txt
+
+.PHONY: golangci-lint golangci-lint-fix
+golangci-lint-fix: ARGS=--fix
+golangci-lint-fix: golangci-lint
+golangci-lint: $(OTEL_GO_MOD_DIRS:%=golangci-lint/%)
+golangci-lint/%: DIR=$*
+golangci-lint/%: | $(GOLANGCI_LINT)
+	@echo 'golangci-lint $(if $(ARGS),$(ARGS) ,)$(DIR)' \
+		&& cd $(DIR) \
+		&& $(GOLANGCI_LINT) run --allow-serial-runners $(ARGS)
+
+.PHONY: crosslink
+crosslink: | $(CROSSLINK)
+	@echo "cross-linking all go modules" \
+		&& $(CROSSLINK)
+
+.PHONY: go-mod-tidy
+go-mod-tidy: $(ALL_GO_MOD_DIRS:%=go-mod-tidy/%)
+go-mod-tidy/%: DIR=$*
+go-mod-tidy/%: | crosslink
+	@echo "$(GO) mod tidy in $(DIR)" \
+		&& cd $(DIR) \
+		&& $(GO) mod tidy
+
+.PHONY: lint-modules
+lint-modules: go-mod-tidy
+
+.PHONY: lint
+lint: misspell lint-modules golangci-lint
+
+.PHONY: vanity-import-check
+vanity-import-check: | $(PORTO)
+	@$(PORTO) --include-internal -l .
+
+.PHONY: misspell
+misspell: | $(MISSPELL)
+	@$(MISSPELL) -w $(ALL_DOCS)
+
+.PHONY: license-check
+license-check:
+	@licRes=$$(for f in $$(find . -type f \( -iname '*.go' -o -iname '*.sh' \) ! -path '**/third_party/*') ; do \
+	           awk '/Copyright The OpenTelemetry Authors|generated|GENERATED/ && NR<=3 { found=1; next } END { if (!found) print FILENAME }' $$f; \
+	   done); \
+	   if [ -n "$${licRes}" ]; then \
+	           echo "license header checking failed:"; echo "$${licRes}"; \
+	           exit 1; \
+	   fi
+
+DEPENDABOT_CONFIG = .github/dependabot.yml
+.PHONY: dependabot-check
+dependabot-check: | $(DBOTCONF)
+	@$(DBOTCONF) verify $(DEPENDABOT_CONFIG) || echo "(run: make dependabot-generate)"
+
+.PHONY: dependabot-generate
+dependabot-generate: | $(DBOTCONF)
+	@$(DBOTCONF) generate > $(DEPENDABOT_CONFIG)
+
+.PHONY: check-clean-work-tree
+check-clean-work-tree:
+	@if ! git diff --quiet; then \
+	  echo; \
+	  echo 'Working tree is not clean, did you forget to run "make precommit"?'; \
+	  echo; \
+	  git status; \
+	  exit 1; \
+	fi
+
+.PHONY: prerelease
+prerelease: | $(MULTIMOD)
+	@[ "${MODSET}" ] || ( echo ">> env var MODSET is not set"; exit 1 )
+	$(MULTIMOD) verify && $(MULTIMOD) prerelease -m ${MODSET}
+
+COMMIT ?= "HEAD"
+.PHONY: add-tags
+add-tags: | $(MULTIMOD)
+	@[ "${MODSET}" ] || ( echo ">> env var MODSET is not set"; exit 1 )
+	$(MULTIMOD) verify && $(MULTIMOD) tag -m ${MODSET} -c ${COMMIT}

vendor/go.opentelemetry.io/otel/README.md

@@ -0,0 +1,108 @@
+# OpenTelemetry-Go
+
+[![CI](https://github.com/open-telemetry/opentelemetry-go/workflows/ci/badge.svg)](https://github.com/open-telemetry/opentelemetry-go/actions?query=workflow%3Aci+branch%3Amain)
+[![codecov.io](https://codecov.io/gh/open-telemetry/opentelemetry-go/coverage.svg?branch=main)](https://app.codecov.io/gh/open-telemetry/opentelemetry-go?branch=main)
+[![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel)](https://pkg.go.dev/go.opentelemetry.io/otel)
+[![Go Report Card](https://goreportcard.com/badge/go.opentelemetry.io/otel)](https://goreportcard.com/report/go.opentelemetry.io/otel)
+[![Slack](https://img.shields.io/badge/slack-@cncf/otel--go-brightgreen.svg?logo=slack)](https://cloud-native.slack.com/archives/C01NPAXACKT)
+
+OpenTelemetry-Go is the [Go](https://golang.org/) implementation of [OpenTelemetry](https://opentelemetry.io/).
+It provides a set of APIs to directly measure performance and behavior of your software and send this data to observability platforms.
+
+## Project Status
+
+| Signal  | Status     | Project |
+| ------- | ---------- | ------- |
+| Traces  | Stable     | N/A     |
+| Metrics | Alpha      | N/A     |
+| Logs    | Frozen [1] | N/A     |
+
+- [1]: The Logs signal development is halted for this project while we develop both Traces and Metrics.
+   No Logs Pull Requests are currently being accepted.
+
+Progress and status specific to this repository is tracked in our local
+[project boards](https://github.com/open-telemetry/opentelemetry-go/projects)
+and
+[milestones](https://github.com/open-telemetry/opentelemetry-go/milestones).
+
+Project versioning information and stability guarantees can be found in the
+[versioning documentation](./VERSIONING.md).
+
+### Compatibility
+
+OpenTelemetry-Go attempts to track the current supported versions of the
+[Go language](https://golang.org/doc/devel/release#policy). The release
+schedule after a new minor version of go is as follows:
+
+- The first release or one month, which ever is sooner, will add build steps for the new go version.
+- The first release after three months will remove support for the oldest go version.
+
+This project is tested on the following systems.
+
+| OS      | Go Version | Architecture |
+| ------- | ---------- | ------------ |
+| Ubuntu  | 1.18       | amd64        |
+| Ubuntu  | 1.17       | amd64        |
+| Ubuntu  | 1.16       | amd64        |
+| Ubuntu  | 1.18       | 386          |
+| Ubuntu  | 1.17       | 386          |
+| Ubuntu  | 1.16       | 386          |
+| MacOS   | 1.18       | amd64        |
+| MacOS   | 1.17       | amd64        |
+| MacOS   | 1.16       | amd64        |
+| Windows | 1.18       | amd64        |
+| Windows | 1.17       | amd64        |
+| Windows | 1.16       | amd64        |
+| Windows | 1.18       | 386          |
+| Windows | 1.17       | 386          |
+| Windows | 1.16       | 386          |
+
+While this project should work for other systems, no compatibility guarantees
+are made for those systems currently.
+
+Go 1.18 was added in March of 2022.
+Go 1.16 will be removed around June 2022.
+
+## Getting Started
+
+You can find a getting started guide on [opentelemetry.io](https://opentelemetry.io/docs/go/getting-started/).
+
+OpenTelemetry's goal is to provide a single set of APIs to capture distributed
+traces and metrics from your application and send them to an observability
+platform. This project allows you to do just that for applications written in
+Go. There are two steps to this process: instrument your application, and
+configure an exporter.
+
+### Instrumentation
+
+To start capturing distributed traces and metric events from your application
+it first needs to be instrumented. The easiest way to do this is by using an
+instrumentation library for your code. Be sure to check out [the officially
+supported instrumentation
+libraries](https://github.com/open-telemetry/opentelemetry-go-contrib/tree/main/instrumentation).
+
+If you need to extend the telemetry an instrumentation library provides or want
+to build your own instrumentation for your application directly you will need
+to use the
+[Go otel](https://pkg.go.dev/go.opentelemetry.io/otel)
+package. The included [examples](./example/) are a good way to see some
+practical uses of this process.
+
+### Export
+
+Now that your application is instrumented to collect telemetry, it needs an
+export pipeline to send that telemetry to an observability platform.
+
+All officially supported exporters for the OpenTelemetry project are contained in the [exporters directory](./exporters).
+
+| Exporter                              | Metrics | Traces |
+| :-----------------------------------: | :-----: | :----: |
+| [Jaeger](./exporters/jaeger/)         |         | ✓      |
+| [OTLP](./exporters/otlp/)             | ✓       | ✓      |
+| [Prometheus](./exporters/prometheus/) | ✓       |        |
+| [stdout](./exporters/stdout/)         | ✓       | ✓      |
+| [Zipkin](./exporters/zipkin/)         |         | ✓      |
+
+## Contributing
+
+See the [contributing documentation](CONTRIBUTING.md).

vendor/go.opentelemetry.io/otel/RELEASING.md

@@ -0,0 +1,132 @@
+# Release Process
+
+## Semantic Convention Generation
+
+If a new version of the OpenTelemetry Specification has been released it will be necessary to generate a new
+semantic convention package from the YAML definitions in the specification repository. There is a `semconvgen` utility
+installed by `make tools` that can be used to generate the a package with the name matching the specification
+version number under the `semconv` package. This will ideally be done soon after the specification release is
+tagged. Make sure that the specification repo contains a checkout of the the latest tagged release so that the
+generated files match the released semantic conventions.
+
+There are currently two categories of semantic conventions that must be generated, `resource` and `trace`.
+
+```
+.tools/semconvgen -i /path/to/specification/repo/semantic_conventions/resource -t semconv/template.j2
+.tools/semconvgen -i /path/to/specification/repo/semantic_conventions/trace -t semconv/template.j2
+```
+
+Using default values for all options other than `input` will result in using the `template.j2` template to
+generate `resource.go` and `trace.go` in `/path/to/otelgo/repo/semconv/<version>`.
+
+There are several ancillary files that are not generated and should be copied into the new package from the
+prior package, with updates made as appropriate to canonical import path statements and constant values.
+These files include:
+
+* doc.go
+* exception.go
+* http(_test)?.go
+* schema.go
+
+Uses of the previous schema version in this repository should be updated to use the newly generated version.
+No tooling for this exists at present, so use find/replace in your editor of choice or craft a `grep | sed`
+pipeline if you like living on the edge.
+
+## Pre-Release
+
+First, decide which module sets will be released and update their versions
+in `versions.yaml`.  Commit this change to a new branch.
+
+Update go.mod for submodules to depend on the new release which will happen in the next step.
+
+1. Run the `prerelease` make target. It creates a branch
+    `prerelease_<module set>_<new tag>` that will contain all release changes.
+
+    ```
+    make prerelease MODSET=<module set>
+    ```
+
+2. Verify the changes.
+
+    ```
+    git diff ...prerelease_<module set>_<new tag>
+    ```
+
+    This should have changed the version for all modules to be `<new tag>`.
+    If these changes look correct, merge them into your pre-release branch:
+
+    ```go
+    git merge prerelease_<module set>_<new tag>
+    ```
+
+3. Update the [Changelog](./CHANGELOG.md).
+   - Make sure all relevant changes for this release are included and are in language that non-contributors to the project can understand.
+       To verify this, you can look directly at the commits since the `<last tag>`.
+
+       ```
+       git --no-pager log --pretty=oneline "<last tag>..HEAD"
+       ```
+
+   - Move all the `Unreleased` changes into a new section following the title scheme (`[<new tag>] - <date of release>`).
+   - Update all the appropriate links at the bottom.
+
+4. Push the changes to upstream and create a Pull Request on GitHub.
+    Be sure to include the curated changes from the [Changelog](./CHANGELOG.md) in the description.
+
+## Tag
+
+Once the Pull Request with all the version changes has been approved and merged it is time to tag the merged commit.
+
+***IMPORTANT***: It is critical you use the same tag that you used in the Pre-Release step!
+Failure to do so will leave things in a broken state. As long as you do not
+change `versions.yaml` between pre-release and this step, things should be fine.
+
+***IMPORTANT***: [There is currently no way to remove an incorrectly tagged version of a Go module](https://github.com/golang/go/issues/34189).
+It is critical you make sure the version you push upstream is correct.
+[Failure to do so will lead to minor emergencies and tough to work around](https://github.com/open-telemetry/opentelemetry-go/issues/331).
+
+1. For each module set that will be released, run the `add-tags` make target
+    using the `<commit-hash>` of the commit on the main branch for the merged Pull Request.
+
+    ```
+    make add-tags MODSET=<module set> COMMIT=<commit hash>
+    ```
+
+    It should only be necessary to provide an explicit `COMMIT` value if the
+    current `HEAD` of your working directory is not the correct commit.
+
+2. Push tags to the upstream remote (not your fork: `github.com/open-telemetry/opentelemetry-go.git`).
+    Make sure you push all sub-modules as well.
+
+    ```
+    git push upstream <new tag>
+    git push upstream <submodules-path/new tag>
+    ...
+    ```
+
+## Release
+
+Finally create a Release for the new `<new tag>` on GitHub.
+The release body should include all the release notes from the Changelog for this release.
+
+## Verify Examples
+
+After releasing verify that examples build outside of the repository.
+
+```
+./verify_examples.sh
+```
+
+The script copies examples into a different directory removes any `replace` declarations in `go.mod` and builds them.
+This ensures they build with the published release, not the local copy.
+
+## Post-Release
+
+### Contrib Repository
+
+Once verified be sure to [make a release for the `contrib` repository](https://github.com/open-telemetry/opentelemetry-go-contrib/blob/main/RELEASING.md) that uses this release.
+
+### Website Documentation
+
+Update [the documentation](./website_docs) for [the OpenTelemetry website](https://opentelemetry.io/docs/go/).
+Importantly, bump any package versions referenced to be the latest one you just released and ensure all code examples still compile and are accurate.

vendor/go.opentelemetry.io/otel/VERSIONING.md

@@ -0,0 +1,224 @@
+# Versioning
+
+This document describes the versioning policy for this repository. This policy
+is designed so the following goals can be achieved.
+
+**Users are provided a codebase of value that is stable and secure.**
+
+## Policy
+
+* Versioning of this project will be idiomatic of a Go project using [Go
+  modules](https://github.com/golang/go/wiki/Modules).
+  * [Semantic import
+    versioning](https://github.com/golang/go/wiki/Modules#semantic-import-versioning)
+    will be used.
+    * Versions will comply with [semver
+      2.0](https://semver.org/spec/v2.0.0.html) with the following exceptions.
+      * New methods may be added to exported API interfaces. All exported
+        interfaces that fall within this exception will include the following
+        paragraph in their public documentation.
+
+        > Warning: methods may be added to this interface in minor releases.
+
+    * If a module is version `v2` or higher, the major version of the module
+      must be included as a `/vN` at the end of the module paths used in
+      `go.mod` files (e.g., `module go.opentelemetry.io/otel/v2`, `require
+      go.opentelemetry.io/otel/v2 v2.0.1`) and in the package import path
+      (e.g., `import "go.opentelemetry.io/otel/v2/trace"`). This includes the
+      paths used in `go get` commands (e.g., `go get
+      go.opentelemetry.io/otel/v2@v2.0.1`.  Note there is both a `/v2` and a
+      `@v2.0.1` in that example. One way to think about it is that the module
+      name now includes the `/v2`, so include `/v2` whenever you are using the
+      module name).
+    * If a module is version `v0` or `v1`, do not include the major version in
+      either the module path or the import path.
+  * Modules will be used to encapsulate signals and components.
+    * Experimental modules still under active development will be versioned at
+      `v0` to imply the stability guarantee defined by
+      [semver](https://semver.org/spec/v2.0.0.html#spec-item-4).
+
+      > Major version zero (0.y.z) is for initial development. Anything MAY
+      > change at any time. The public API SHOULD NOT be considered stable.
+
+    * Mature modules for which we guarantee a stable public API will be versioned
+      with a major version greater than `v0`.
+      * The decision to make a module stable will be made on a case-by-case
+        basis by the maintainers of this project.
+    * Experimental modules will start their versioning at `v0.0.0` and will
+      increment their minor version when backwards incompatible changes are
+      released and increment their patch version when backwards compatible
+      changes are released.
+    * All stable modules that use the same major version number will use the
+      same entire version number.
+      * Stable modules may be released with an incremented minor or patch
+        version even though that module has not been changed, but rather so
+        that it will remain at the same version as other stable modules that
+        did undergo change.
+      * When an experimental module becomes stable a new stable module version
+        will be released and will include this now stable module. The new
+        stable module version will be an increment of the minor version number
+        and will be applied to all existing stable modules as well as the newly
+        stable module being released.
+* Versioning of the associated [contrib
+  repository](https://github.com/open-telemetry/opentelemetry-go-contrib) of
+  this project will be idiomatic of a Go project using [Go
+  modules](https://github.com/golang/go/wiki/Modules).
+  * [Semantic import
+    versioning](https://github.com/golang/go/wiki/Modules#semantic-import-versioning)
+    will be used.
+    * Versions will comply with [semver 2.0](https://semver.org/spec/v2.0.0.html).
+    * If a module is version `v2` or higher, the
+      major version of the module must be included as a `/vN` at the end of the
+      module paths used in `go.mod` files (e.g., `module
+      go.opentelemetry.io/contrib/instrumentation/host/v2`, `require
+      go.opentelemetry.io/contrib/instrumentation/host/v2 v2.0.1`) and in the
+      package import path (e.g., `import
+      "go.opentelemetry.io/contrib/instrumentation/host/v2"`). This includes
+      the paths used in `go get` commands (e.g., `go get
+      go.opentelemetry.io/contrib/instrumentation/host/v2@v2.0.1`.  Note there
+      is both a `/v2` and a `@v2.0.1` in that example. One way to think about
+      it is that the module name now includes the `/v2`, so include `/v2`
+      whenever you are using the module name).
+    * If a module is version `v0` or `v1`, do not include the major version
+      in either the module path or the import path.
+  * In addition to public APIs, telemetry produced by stable instrumentation
+    will remain stable and backwards compatible. This is to avoid breaking
+    alerts and dashboard.
+  * Modules will be used to encapsulate instrumentation, detectors, exporters,
+    propagators, and any other independent sets of related components.
+    * Experimental modules still under active development will be versioned at
+      `v0` to imply the stability guarantee defined by
+      [semver](https://semver.org/spec/v2.0.0.html#spec-item-4).
+
+      > Major version zero (0.y.z) is for initial development. Anything MAY
+      > change at any time. The public API SHOULD NOT be considered stable.
+
+    * Mature modules for which we guarantee a stable public API and telemetry will
+      be versioned with a major version greater than `v0`.
+    * Experimental modules will start their versioning at `v0.0.0` and will
+      increment their minor version when backwards incompatible changes are
+      released and increment their patch version when backwards compatible
+      changes are released.
+    * Stable contrib modules cannot depend on experimental modules from this
+      project.
+    * All stable contrib modules of the same major version with this project
+      will use the same entire version as this project.
+      * Stable modules may be released with an incremented minor or patch
+        version even though that module's code has not been changed. Instead
+        the only change that will have been included is to have updated that
+        modules dependency on this project's stable APIs.
+      * When an experimental module in contrib becomes stable a new stable
+        module version will be released and will include this now stable
+        module. The new stable module version will be an increment of the minor
+        version number and will be applied to all existing stable contrib
+        modules, this project's modules, and the newly stable module being
+        released.
+  * Contrib modules will be kept up to date with this project's releases.
+    * Due to the dependency contrib modules will implicitly have on this
+      project's modules the release of stable contrib modules to match the
+      released version number will be staggered after this project's release.
+      There is no explicit time guarantee for how long after this projects
+      release the contrib release will be. Effort should be made to keep them
+      as close in time as possible.
+    * No additional stable release in this project can be made until the
+      contrib repository has a matching stable release.
+    * No release can be made in the contrib repository after this project's
+      stable release except for a stable release of the contrib repository.
+* GitHub releases will be made for all releases.
+* Go modules will be made available at Go package mirrors.
+
+## Example Versioning Lifecycle
+
+To better understand the implementation of the above policy the following
+example is provided. This project is simplified to include only the following
+modules and their versions:
+
+* `otel`: `v0.14.0`
+* `otel/trace`: `v0.14.0`
+* `otel/metric`: `v0.14.0`
+* `otel/baggage`: `v0.14.0`
+* `otel/sdk/trace`: `v0.14.0`
+* `otel/sdk/metric`: `v0.14.0`
+
+These modules have been developed to a point where the `otel/trace`,
+`otel/baggage`, and `otel/sdk/trace` modules have reached a point that they
+should be considered for a stable release. The `otel/metric` and
+`otel/sdk/metric` are still under active development and the `otel` module
+depends on both `otel/trace` and `otel/metric`.
+
+The `otel` package is refactored to remove its dependencies on `otel/metric` so
+it can be released as stable as well. With that done the following release
+candidates are made:
+
+* `otel`: `v1.0.0-RC1`
+* `otel/trace`: `v1.0.0-RC1`
+* `otel/baggage`: `v1.0.0-RC1`
+* `otel/sdk/trace`: `v1.0.0-RC1`
+
+The `otel/metric` and `otel/sdk/metric` modules remain at `v0.14.0`.
+
+A few minor issues are discovered in the `otel/trace` package. These issues are
+resolved with some minor, but backwards incompatible, changes and are released
+as a second release candidate:
+
+* `otel`: `v1.0.0-RC2`
+* `otel/trace`: `v1.0.0-RC2`
+* `otel/baggage`: `v1.0.0-RC2`
+* `otel/sdk/trace`: `v1.0.0-RC2`
+
+Notice that all module version numbers are incremented to adhere to our
+versioning policy.
+
+After these release candidates have been evaluated to satisfaction, they are
+released as version `v1.0.0`.
+
+* `otel`: `v1.0.0`
+* `otel/trace`: `v1.0.0`
+* `otel/baggage`: `v1.0.0`
+* `otel/sdk/trace`: `v1.0.0`
+
+Since both the `go` utility and the Go module system support [the semantic
+versioning definition of
+precedence](https://semver.org/spec/v2.0.0.html#spec-item-11), this release
+will correctly be interpreted as the successor to the previous release
+candidates.
+
+Active development of this project continues. The `otel/metric` module now has
+backwards incompatible changes to its API that need to be released and the
+`otel/baggage` module has a minor bug fix that needs to be released. The
+following release is made:
+
+* `otel`: `v1.0.1`
+* `otel/trace`: `v1.0.1`
+* `otel/metric`: `v0.15.0`
+* `otel/baggage`: `v1.0.1`
+* `otel/sdk/trace`: `v1.0.1`
+* `otel/sdk/metric`: `v0.15.0`
+
+Notice that, again, all stable module versions are incremented in unison and
+the `otel/sdk/metric` package, which depends on the `otel/metric` package, also
+bumped its version. This bump of the `otel/sdk/metric` package makes sense
+given their coupling, though it is not explicitly required by our versioning
+policy.
+
+As we progress, the `otel/metric` and `otel/sdk/metric` packages have reached a
+point where they should be evaluated for stability. The `otel` module is
+reintegrated with the `otel/metric` package and the following release is made:
+
+* `otel`: `v1.1.0-RC1`
+* `otel/trace`: `v1.1.0-RC1`
+* `otel/metric`: `v1.1.0-RC1`
+* `otel/baggage`: `v1.1.0-RC1`
+* `otel/sdk/trace`: `v1.1.0-RC1`
+* `otel/sdk/metric`: `v1.1.0-RC1`
+
+All the modules are evaluated and determined to a viable stable release. They
+are then released as version `v1.1.0` (the minor version is incremented to
+indicate the addition of new signal).
+
+* `otel`: `v1.1.0`
+* `otel/trace`: `v1.1.0`
+* `otel/metric`: `v1.1.0`
+* `otel/baggage`: `v1.1.0`
+* `otel/sdk/trace`: `v1.1.0`
+* `otel/sdk/metric`: `v1.1.0`

vendor/go.opentelemetry.io/otel/attribute/doc.go

@@ -0,0 +1,16 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package attribute provides key and value attributes.
+package attribute // import "go.opentelemetry.io/otel/attribute"

vendor/go.opentelemetry.io/otel/attribute/encoder.go

@@ -0,0 +1,150 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"bytes"
+	"sync"
+	"sync/atomic"
+)
+
+type (
+	// Encoder is a mechanism for serializing a label set into a
+	// specific string representation that supports caching, to
+	// avoid repeated serialization. An example could be an
+	// exporter encoding the label set into a wire representation.
+	Encoder interface {
+		// Encode returns the serialized encoding of the label
+		// set using its Iterator.  This result may be cached
+		// by a attribute.Set.
+		Encode(iterator Iterator) string
+
+		// ID returns a value that is unique for each class of
+		// label encoder.  Label encoders allocate these using
+		// `NewEncoderID`.
+		ID() EncoderID
+	}
+
+	// EncoderID is used to identify distinct Encoder
+	// implementations, for caching encoded results.
+	EncoderID struct {
+		value uint64
+	}
+
+	// defaultLabelEncoder uses a sync.Pool of buffers to reduce
+	// the number of allocations used in encoding labels.  This
+	// implementation encodes a comma-separated list of key=value,
+	// with '/'-escaping of '=', ',', and '\'.
+	defaultLabelEncoder struct {
+		// pool is a pool of labelset builders.  The buffers in this
+		// pool grow to a size that most label encodings will not
+		// allocate new memory.
+		pool sync.Pool // *bytes.Buffer
+	}
+)
+
+// escapeChar is used to ensure uniqueness of the label encoding where
+// keys or values contain either '=' or ','.  Since there is no parser
+// needed for this encoding and its only requirement is to be unique,
+// this choice is arbitrary.  Users will see these in some exporters
+// (e.g., stdout), so the backslash ('\') is used as a conventional choice.
+const escapeChar = '\\'
+
+var (
+	_ Encoder = &defaultLabelEncoder{}
+
+	// encoderIDCounter is for generating IDs for other label
+	// encoders.
+	encoderIDCounter uint64
+
+	defaultEncoderOnce     sync.Once
+	defaultEncoderID       = NewEncoderID()
+	defaultEncoderInstance *defaultLabelEncoder
+)
+
+// NewEncoderID returns a unique label encoder ID. It should be
+// called once per each type of label encoder. Preferably in init() or
+// in var definition.
+func NewEncoderID() EncoderID {
+	return EncoderID{value: atomic.AddUint64(&encoderIDCounter, 1)}
+}
+
+// DefaultEncoder returns a label encoder that encodes labels
+// in such a way that each escaped label's key is followed by an equal
+// sign and then by an escaped label's value. All key-value pairs are
+// separated by a comma.
+//
+// Escaping is done by prepending a backslash before either a
+// backslash, equal sign or a comma.
+func DefaultEncoder() Encoder {
+	defaultEncoderOnce.Do(func() {
+		defaultEncoderInstance = &defaultLabelEncoder{
+			pool: sync.Pool{
+				New: func() interface{} {
+					return &bytes.Buffer{}
+				},
+			},
+		}
+	})
+	return defaultEncoderInstance
+}
+
+// Encode is a part of an implementation of the LabelEncoder
+// interface.
+func (d *defaultLabelEncoder) Encode(iter Iterator) string {
+	buf := d.pool.Get().(*bytes.Buffer)
+	defer d.pool.Put(buf)
+	buf.Reset()
+
+	for iter.Next() {
+		i, keyValue := iter.IndexedLabel()
+		if i > 0 {
+			_, _ = buf.WriteRune(',')
+		}
+		copyAndEscape(buf, string(keyValue.Key))
+
+		_, _ = buf.WriteRune('=')
+
+		if keyValue.Value.Type() == STRING {
+			copyAndEscape(buf, keyValue.Value.AsString())
+		} else {
+			_, _ = buf.WriteString(keyValue.Value.Emit())
+		}
+	}
+	return buf.String()
+}
+
+// ID is a part of an implementation of the LabelEncoder interface.
+func (*defaultLabelEncoder) ID() EncoderID {
+	return defaultEncoderID
+}
+
+// copyAndEscape escapes `=`, `,` and its own escape character (`\`),
+// making the default encoding unique.
+func copyAndEscape(buf *bytes.Buffer, val string) {
+	for _, ch := range val {
+		switch ch {
+		case '=', ',', escapeChar:
+			buf.WriteRune(escapeChar)
+		}
+		buf.WriteRune(ch)
+	}
+}
+
+// Valid returns true if this encoder ID was allocated by
+// `NewEncoderID`.  Invalid encoder IDs will not be cached.
+func (id EncoderID) Valid() bool {
+	return id.value != 0
+}

vendor/go.opentelemetry.io/otel/attribute/iterator.go

@@ -0,0 +1,143 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+// Iterator allows iterating over the set of labels in order,
+// sorted by key.
+type Iterator struct {
+	storage *Set
+	idx     int
+}
+
+// MergeIterator supports iterating over two sets of labels while
+// eliminating duplicate values from the combined set.  The first
+// iterator value takes precedence.
+type MergeIterator struct {
+	one     oneIterator
+	two     oneIterator
+	current KeyValue
+}
+
+type oneIterator struct {
+	iter  Iterator
+	done  bool
+	label KeyValue
+}
+
+// Next moves the iterator to the next position. Returns false if there
+// are no more labels.
+func (i *Iterator) Next() bool {
+	i.idx++
+	return i.idx < i.Len()
+}
+
+// Label returns current KeyValue. Must be called only after Next returns
+// true.
+func (i *Iterator) Label() KeyValue {
+	kv, _ := i.storage.Get(i.idx)
+	return kv
+}
+
+// Attribute is a synonym for Label().
+func (i *Iterator) Attribute() KeyValue {
+	return i.Label()
+}
+
+// IndexedLabel returns current index and attribute. Must be called only
+// after Next returns true.
+func (i *Iterator) IndexedLabel() (int, KeyValue) {
+	return i.idx, i.Label()
+}
+
+// Len returns a number of labels in the iterator's `*Set`.
+func (i *Iterator) Len() int {
+	return i.storage.Len()
+}
+
+// ToSlice is a convenience function that creates a slice of labels
+// from the passed iterator. The iterator is set up to start from the
+// beginning before creating the slice.
+func (i *Iterator) ToSlice() []KeyValue {
+	l := i.Len()
+	if l == 0 {
+		return nil
+	}
+	i.idx = -1
+	slice := make([]KeyValue, 0, l)
+	for i.Next() {
+		slice = append(slice, i.Label())
+	}
+	return slice
+}
+
+// NewMergeIterator returns a MergeIterator for merging two label sets
+// Duplicates are resolved by taking the value from the first set.
+func NewMergeIterator(s1, s2 *Set) MergeIterator {
+	mi := MergeIterator{
+		one: makeOne(s1.Iter()),
+		two: makeOne(s2.Iter()),
+	}
+	return mi
+}
+
+func makeOne(iter Iterator) oneIterator {
+	oi := oneIterator{
+		iter: iter,
+	}
+	oi.advance()
+	return oi
+}
+
+func (oi *oneIterator) advance() {
+	if oi.done = !oi.iter.Next(); !oi.done {
+		oi.label = oi.iter.Label()
+	}
+}
+
+// Next returns true if there is another label available.
+func (m *MergeIterator) Next() bool {
+	if m.one.done && m.two.done {
+		return false
+	}
+	if m.one.done {
+		m.current = m.two.label
+		m.two.advance()
+		return true
+	}
+	if m.two.done {
+		m.current = m.one.label
+		m.one.advance()
+		return true
+	}
+	if m.one.label.Key == m.two.label.Key {
+		m.current = m.one.label // first iterator label value wins
+		m.one.advance()
+		m.two.advance()
+		return true
+	}
+	if m.one.label.Key < m.two.label.Key {
+		m.current = m.one.label
+		m.one.advance()
+		return true
+	}
+	m.current = m.two.label
+	m.two.advance()
+	return true
+}
+
+// Label returns the current value after Next() returns true.
+func (m *MergeIterator) Label() KeyValue {
+	return m.current
+}

vendor/go.opentelemetry.io/otel/attribute/key.go

@@ -0,0 +1,134 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+// Key represents the key part in key-value pairs. It's a string. The
+// allowed character set in the key depends on the use of the key.
+type Key string
+
+// Bool creates a KeyValue instance with a BOOL Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Bool(name, value).
+func (k Key) Bool(v bool) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: BoolValue(v),
+	}
+}
+
+// BoolSlice creates a KeyValue instance with a BOOLSLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- BoolSlice(name, value).
+func (k Key) BoolSlice(v []bool) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: BoolSliceValue(v),
+	}
+}
+
+// Int creates a KeyValue instance with an INT64 Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Int(name, value).
+func (k Key) Int(v int) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: IntValue(v),
+	}
+}
+
+// IntSlice creates a KeyValue instance with an INT64SLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- IntSlice(name, value).
+func (k Key) IntSlice(v []int) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: IntSliceValue(v),
+	}
+}
+
+// Int64 creates a KeyValue instance with an INT64 Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Int64(name, value).
+func (k Key) Int64(v int64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Int64Value(v),
+	}
+}
+
+// Int64Slice creates a KeyValue instance with an INT64SLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Int64Slice(name, value).
+func (k Key) Int64Slice(v []int64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Int64SliceValue(v),
+	}
+}
+
+// Float64 creates a KeyValue instance with a FLOAT64 Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Float64(name, value).
+func (k Key) Float64(v float64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Float64Value(v),
+	}
+}
+
+// Float64Slice creates a KeyValue instance with a FLOAT64SLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Float64(name, value).
+func (k Key) Float64Slice(v []float64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Float64SliceValue(v),
+	}
+}
+
+// String creates a KeyValue instance with a STRING Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- String(name, value).
+func (k Key) String(v string) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: StringValue(v),
+	}
+}
+
+// StringSlice creates a KeyValue instance with a STRINGSLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- StringSlice(name, value).
+func (k Key) StringSlice(v []string) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: StringSliceValue(v),
+	}
+}
+
+// Defined returns true for non-empty keys.
+func (k Key) Defined() bool {
+	return len(k) != 0
+}

vendor/go.opentelemetry.io/otel/attribute/kv.go

@@ -0,0 +1,86 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"fmt"
+)
+
+// KeyValue holds a key and value pair.
+type KeyValue struct {
+	Key   Key
+	Value Value
+}
+
+// Valid returns if kv is a valid OpenTelemetry attribute.
+func (kv KeyValue) Valid() bool {
+	return kv.Key.Defined() && kv.Value.Type() != INVALID
+}
+
+// Bool creates a KeyValue with a BOOL Value type.
+func Bool(k string, v bool) KeyValue {
+	return Key(k).Bool(v)
+}
+
+// BoolSlice creates a KeyValue with a BOOLSLICE Value type.
+func BoolSlice(k string, v []bool) KeyValue {
+	return Key(k).BoolSlice(v)
+}
+
+// Int creates a KeyValue with an INT64 Value type.
+func Int(k string, v int) KeyValue {
+	return Key(k).Int(v)
+}
+
+// IntSlice creates a KeyValue with an INT64SLICE Value type.
+func IntSlice(k string, v []int) KeyValue {
+	return Key(k).IntSlice(v)
+}
+
+// Int64 creates a KeyValue with an INT64 Value type.
+func Int64(k string, v int64) KeyValue {
+	return Key(k).Int64(v)
+}
+
+// Int64Slice creates a KeyValue with an INT64SLICE Value type.
+func Int64Slice(k string, v []int64) KeyValue {
+	return Key(k).Int64Slice(v)
+}
+
+// Float64 creates a KeyValue with a FLOAT64 Value type.
+func Float64(k string, v float64) KeyValue {
+	return Key(k).Float64(v)
+}
+
+// Float64Slice creates a KeyValue with a FLOAT64SLICE Value type.
+func Float64Slice(k string, v []float64) KeyValue {
+	return Key(k).Float64Slice(v)
+}
+
+// String creates a KeyValue with a STRING Value type.
+func String(k, v string) KeyValue {
+	return Key(k).String(v)
+}
+
+// StringSlice creates a KeyValue with a STRINGSLICE Value type.
+func StringSlice(k string, v []string) KeyValue {
+	return Key(k).StringSlice(v)
+}
+
+// Stringer creates a new key-value pair with a passed name and a string
+// value generated by the passed Stringer interface.
+func Stringer(k string, v fmt.Stringer) KeyValue {
+	return Key(k).String(v.String())
+}

vendor/go.opentelemetry.io/otel/attribute/set.go

@@ -0,0 +1,435 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"encoding/json"
+	"reflect"
+	"sort"
+)
+
+type (
+	// Set is the representation for a distinct label set.  It
+	// manages an immutable set of labels, with an internal cache
+	// for storing label encodings.
+	//
+	// This type supports the `Equivalent` method of comparison
+	// using values of type `Distinct`.
+	//
+	// This type is used to implement:
+	// 1. Metric labels
+	// 2. Resource sets
+	// 3. Correlation map (TODO)
+	Set struct {
+		equivalent Distinct
+	}
+
+	// Distinct wraps a variable-size array of `KeyValue`,
+	// constructed with keys in sorted order.  This can be used as
+	// a map key or for equality checking between Sets.
+	Distinct struct {
+		iface interface{}
+	}
+
+	// Filter supports removing certain labels from label sets.
+	// When the filter returns true, the label will be kept in
+	// the filtered label set.  When the filter returns false, the
+	// label is excluded from the filtered label set, and the
+	// label instead appears in the `removed` list of excluded labels.
+	Filter func(KeyValue) bool
+
+	// Sortable implements `sort.Interface`, used for sorting
+	// `KeyValue`.  This is an exported type to support a
+	// memory optimization.  A pointer to one of these is needed
+	// for the call to `sort.Stable()`, which the caller may
+	// provide in order to avoid an allocation.  See
+	// `NewSetWithSortable()`.
+	Sortable []KeyValue
+)
+
+var (
+	// keyValueType is used in `computeDistinctReflect`.
+	keyValueType = reflect.TypeOf(KeyValue{})
+
+	// emptySet is returned for empty label sets.
+	emptySet = &Set{
+		equivalent: Distinct{
+			iface: [0]KeyValue{},
+		},
+	}
+)
+
+// EmptySet returns a reference to a Set with no elements.
+//
+// This is a convenience provided for optimized calling utility.
+func EmptySet() *Set {
+	return emptySet
+}
+
+// reflect abbreviates `reflect.ValueOf`.
+func (d Distinct) reflect() reflect.Value {
+	return reflect.ValueOf(d.iface)
+}
+
+// Valid returns true if this value refers to a valid `*Set`.
+func (d Distinct) Valid() bool {
+	return d.iface != nil
+}
+
+// Len returns the number of labels in this set.
+func (l *Set) Len() int {
+	if l == nil || !l.equivalent.Valid() {
+		return 0
+	}
+	return l.equivalent.reflect().Len()
+}
+
+// Get returns the KeyValue at ordered position `idx` in this set.
+func (l *Set) Get(idx int) (KeyValue, bool) {
+	if l == nil {
+		return KeyValue{}, false
+	}
+	value := l.equivalent.reflect()
+
+	if idx >= 0 && idx < value.Len() {
+		// Note: The Go compiler successfully avoids an allocation for
+		// the interface{} conversion here:
+		return value.Index(idx).Interface().(KeyValue), true
+	}
+
+	return KeyValue{}, false
+}
+
+// Value returns the value of a specified key in this set.
+func (l *Set) Value(k Key) (Value, bool) {
+	if l == nil {
+		return Value{}, false
+	}
+	rValue := l.equivalent.reflect()
+	vlen := rValue.Len()
+
+	idx := sort.Search(vlen, func(idx int) bool {
+		return rValue.Index(idx).Interface().(KeyValue).Key >= k
+	})
+	if idx >= vlen {
+		return Value{}, false
+	}
+	keyValue := rValue.Index(idx).Interface().(KeyValue)
+	if k == keyValue.Key {
+		return keyValue.Value, true
+	}
+	return Value{}, false
+}
+
+// HasValue tests whether a key is defined in this set.
+func (l *Set) HasValue(k Key) bool {
+	if l == nil {
+		return false
+	}
+	_, ok := l.Value(k)
+	return ok
+}
+
+// Iter returns an iterator for visiting the labels in this set.
+func (l *Set) Iter() Iterator {
+	return Iterator{
+		storage: l,
+		idx:     -1,
+	}
+}
+
+// ToSlice returns the set of labels belonging to this set, sorted,
+// where keys appear no more than once.
+func (l *Set) ToSlice() []KeyValue {
+	iter := l.Iter()
+	return iter.ToSlice()
+}
+
+// Equivalent returns a value that may be used as a map key.  The
+// Distinct type guarantees that the result will equal the equivalent
+// Distinct value of any label set with the same elements as this,
+// where sets are made unique by choosing the last value in the input
+// for any given key.
+func (l *Set) Equivalent() Distinct {
+	if l == nil || !l.equivalent.Valid() {
+		return emptySet.equivalent
+	}
+	return l.equivalent
+}
+
+// Equals returns true if the argument set is equivalent to this set.
+func (l *Set) Equals(o *Set) bool {
+	return l.Equivalent() == o.Equivalent()
+}
+
+// Encoded returns the encoded form of this set, according to
+// `encoder`.
+func (l *Set) Encoded(encoder Encoder) string {
+	if l == nil || encoder == nil {
+		return ""
+	}
+
+	return encoder.Encode(l.Iter())
+}
+
+func empty() Set {
+	return Set{
+		equivalent: emptySet.equivalent,
+	}
+}
+
+// NewSet returns a new `Set`.  See the documentation for
+// `NewSetWithSortableFiltered` for more details.
+//
+// Except for empty sets, this method adds an additional allocation
+// compared with calls that include a `*Sortable`.
+func NewSet(kvs ...KeyValue) Set {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty()
+	}
+	s, _ := NewSetWithSortableFiltered(kvs, new(Sortable), nil)
+	return s
+}
+
+// NewSetWithSortable returns a new `Set`.  See the documentation for
+// `NewSetWithSortableFiltered` for more details.
+//
+// This call includes a `*Sortable` option as a memory optimization.
+func NewSetWithSortable(kvs []KeyValue, tmp *Sortable) Set {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty()
+	}
+	s, _ := NewSetWithSortableFiltered(kvs, tmp, nil)
+	return s
+}
+
+// NewSetWithFiltered returns a new `Set`.  See the documentation for
+// `NewSetWithSortableFiltered` for more details.
+//
+// This call includes a `Filter` to include/exclude label keys from
+// the return value.  Excluded keys are returned as a slice of label
+// values.
+func NewSetWithFiltered(kvs []KeyValue, filter Filter) (Set, []KeyValue) {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty(), nil
+	}
+	return NewSetWithSortableFiltered(kvs, new(Sortable), filter)
+}
+
+// NewSetWithSortableFiltered returns a new `Set`.
+//
+// Duplicate keys are eliminated by taking the last value.  This
+// re-orders the input slice so that unique last-values are contiguous
+// at the end of the slice.
+//
+// This ensures the following:
+//
+// - Last-value-wins semantics
+// - Caller sees the reordering, but doesn't lose values
+// - Repeated call preserve last-value wins.
+//
+// Note that methods are defined on `*Set`, although this returns `Set`.
+// Callers can avoid memory allocations by:
+//
+// - allocating a `Sortable` for use as a temporary in this method
+// - allocating a `Set` for storing the return value of this
+//   constructor.
+//
+// The result maintains a cache of encoded labels, by attribute.EncoderID.
+// This value should not be copied after its first use.
+//
+// The second `[]KeyValue` return value is a list of labels that were
+// excluded by the Filter (if non-nil).
+func NewSetWithSortableFiltered(kvs []KeyValue, tmp *Sortable, filter Filter) (Set, []KeyValue) {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty(), nil
+	}
+
+	*tmp = kvs
+
+	// Stable sort so the following de-duplication can implement
+	// last-value-wins semantics.
+	sort.Stable(tmp)
+
+	*tmp = nil
+
+	position := len(kvs) - 1
+	offset := position - 1
+
+	// The requirements stated above require that the stable
+	// result be placed in the end of the input slice, while
+	// overwritten values are swapped to the beginning.
+	//
+	// De-duplicate with last-value-wins semantics.  Preserve
+	// duplicate values at the beginning of the input slice.
+	for ; offset >= 0; offset-- {
+		if kvs[offset].Key == kvs[position].Key {
+			continue
+		}
+		position--
+		kvs[offset], kvs[position] = kvs[position], kvs[offset]
+	}
+	if filter != nil {
+		return filterSet(kvs[position:], filter)
+	}
+	return Set{
+		equivalent: computeDistinct(kvs[position:]),
+	}, nil
+}
+
+// filterSet reorders `kvs` so that included keys are contiguous at
+// the end of the slice, while excluded keys precede the included keys.
+func filterSet(kvs []KeyValue, filter Filter) (Set, []KeyValue) {
+	var excluded []KeyValue
+
+	// Move labels that do not match the filter so
+	// they're adjacent before calling computeDistinct().
+	distinctPosition := len(kvs)
+
+	// Swap indistinct keys forward and distinct keys toward the
+	// end of the slice.
+	offset := len(kvs) - 1
+	for ; offset >= 0; offset-- {
+		if filter(kvs[offset]) {
+			distinctPosition--
+			kvs[offset], kvs[distinctPosition] = kvs[distinctPosition], kvs[offset]
+			continue
+		}
+	}
+	excluded = kvs[:distinctPosition]
+
+	return Set{
+		equivalent: computeDistinct(kvs[distinctPosition:]),
+	}, excluded
+}
+
+// Filter returns a filtered copy of this `Set`.  See the
+// documentation for `NewSetWithSortableFiltered` for more details.
+func (l *Set) Filter(re Filter) (Set, []KeyValue) {
+	if re == nil {
+		return Set{
+			equivalent: l.equivalent,
+		}, nil
+	}
+
+	// Note: This could be refactored to avoid the temporary slice
+	// allocation, if it proves to be expensive.
+	return filterSet(l.ToSlice(), re)
+}
+
+// computeDistinct returns a `Distinct` using either the fixed- or
+// reflect-oriented code path, depending on the size of the input.
+// The input slice is assumed to already be sorted and de-duplicated.
+func computeDistinct(kvs []KeyValue) Distinct {
+	iface := computeDistinctFixed(kvs)
+	if iface == nil {
+		iface = computeDistinctReflect(kvs)
+	}
+	return Distinct{
+		iface: iface,
+	}
+}
+
+// computeDistinctFixed computes a `Distinct` for small slices.  It
+// returns nil if the input is too large for this code path.
+func computeDistinctFixed(kvs []KeyValue) interface{} {
+	switch len(kvs) {
+	case 1:
+		ptr := new([1]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 2:
+		ptr := new([2]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 3:
+		ptr := new([3]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 4:
+		ptr := new([4]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 5:
+		ptr := new([5]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 6:
+		ptr := new([6]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 7:
+		ptr := new([7]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 8:
+		ptr := new([8]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 9:
+		ptr := new([9]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 10:
+		ptr := new([10]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	default:
+		return nil
+	}
+}
+
+// computeDistinctReflect computes a `Distinct` using reflection,
+// works for any size input.
+func computeDistinctReflect(kvs []KeyValue) interface{} {
+	at := reflect.New(reflect.ArrayOf(len(kvs), keyValueType)).Elem()
+	for i, keyValue := range kvs {
+		*(at.Index(i).Addr().Interface().(*KeyValue)) = keyValue
+	}
+	return at.Interface()
+}
+
+// MarshalJSON returns the JSON encoding of the `*Set`.
+func (l *Set) MarshalJSON() ([]byte, error) {
+	return json.Marshal(l.equivalent.iface)
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this exporter.
+func (l Set) MarshalLog() interface{} {
+	kvs := make(map[string]string)
+	for _, kv := range l.ToSlice() {
+		kvs[string(kv.Key)] = kv.Value.Emit()
+	}
+	return kvs
+}
+
+// Len implements `sort.Interface`.
+func (l *Sortable) Len() int {
+	return len(*l)
+}
+
+// Swap implements `sort.Interface`.
+func (l *Sortable) Swap(i, j int) {
+	(*l)[i], (*l)[j] = (*l)[j], (*l)[i]
+}
+
+// Less implements `sort.Interface`.
+func (l *Sortable) Less(i, j int) bool {
+	return (*l)[i].Key < (*l)[j].Key
+}

vendor/go.opentelemetry.io/otel/attribute/type_string.go

@@ -0,0 +1,31 @@
+// Code generated by "stringer -type=Type"; DO NOT EDIT.
+
+package attribute
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[INVALID-0]
+	_ = x[BOOL-1]
+	_ = x[INT64-2]
+	_ = x[FLOAT64-3]
+	_ = x[STRING-4]
+	_ = x[BOOLSLICE-5]
+	_ = x[INT64SLICE-6]
+	_ = x[FLOAT64SLICE-7]
+	_ = x[STRINGSLICE-8]
+}
+
+const _Type_name = "INVALIDBOOLINT64FLOAT64STRINGBOOLSLICEINT64SLICEFLOAT64SLICESTRINGSLICE"
+
+var _Type_index = [...]uint8{0, 7, 11, 16, 23, 29, 38, 48, 60, 71}
+
+func (i Type) String() string {
+	if i < 0 || i >= Type(len(_Type_index)-1) {
+		return "Type(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _Type_name[_Type_index[i]:_Type_index[i+1]]
+}

vendor/go.opentelemetry.io/otel/attribute/value.go

@@ -0,0 +1,271 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+
+	"go.opentelemetry.io/otel/internal"
+)
+
+//go:generate stringer -type=Type
+
+// Type describes the type of the data Value holds.
+type Type int
+
+// Value represents the value part in key-value pairs.
+type Value struct {
+	vtype    Type
+	numeric  uint64
+	stringly string
+	slice    interface{}
+}
+
+const (
+	// INVALID is used for a Value with no value set.
+	INVALID Type = iota
+	// BOOL is a boolean Type Value.
+	BOOL
+	// INT64 is a 64-bit signed integral Type Value.
+	INT64
+	// FLOAT64 is a 64-bit floating point Type Value.
+	FLOAT64
+	// STRING is a string Type Value.
+	STRING
+	// BOOLSLICE is a slice of booleans Type Value.
+	BOOLSLICE
+	// INT64SLICE is a slice of 64-bit signed integral numbers Type Value.
+	INT64SLICE
+	// FLOAT64SLICE is a slice of 64-bit floating point numbers Type Value.
+	FLOAT64SLICE
+	// STRINGSLICE is a slice of strings Type Value.
+	STRINGSLICE
+)
+
+// BoolValue creates a BOOL Value.
+func BoolValue(v bool) Value {
+	return Value{
+		vtype:   BOOL,
+		numeric: internal.BoolToRaw(v),
+	}
+}
+
+// BoolSliceValue creates a BOOLSLICE Value.
+func BoolSliceValue(v []bool) Value {
+	cp := make([]bool, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: BOOLSLICE,
+		slice: &cp,
+	}
+}
+
+// IntValue creates an INT64 Value.
+func IntValue(v int) Value {
+	return Int64Value(int64(v))
+}
+
+// IntSliceValue creates an INTSLICE Value.
+func IntSliceValue(v []int) Value {
+	cp := make([]int64, 0, len(v))
+	for _, i := range v {
+		cp = append(cp, int64(i))
+	}
+	return Value{
+		vtype: INT64SLICE,
+		slice: &cp,
+	}
+}
+
+// Int64Value creates an INT64 Value.
+func Int64Value(v int64) Value {
+	return Value{
+		vtype:   INT64,
+		numeric: internal.Int64ToRaw(v),
+	}
+}
+
+// Int64SliceValue creates an INT64SLICE Value.
+func Int64SliceValue(v []int64) Value {
+	cp := make([]int64, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: INT64SLICE,
+		slice: &cp,
+	}
+}
+
+// Float64Value creates a FLOAT64 Value.
+func Float64Value(v float64) Value {
+	return Value{
+		vtype:   FLOAT64,
+		numeric: internal.Float64ToRaw(v),
+	}
+}
+
+// Float64SliceValue creates a FLOAT64SLICE Value.
+func Float64SliceValue(v []float64) Value {
+	cp := make([]float64, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: FLOAT64SLICE,
+		slice: &cp,
+	}
+}
+
+// StringValue creates a STRING Value.
+func StringValue(v string) Value {
+	return Value{
+		vtype:    STRING,
+		stringly: v,
+	}
+}
+
+// StringSliceValue creates a STRINGSLICE Value.
+func StringSliceValue(v []string) Value {
+	cp := make([]string, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: STRINGSLICE,
+		slice: &cp,
+	}
+}
+
+// Type returns a type of the Value.
+func (v Value) Type() Type {
+	return v.vtype
+}
+
+// AsBool returns the bool value. Make sure that the Value's type is
+// BOOL.
+func (v Value) AsBool() bool {
+	return internal.RawToBool(v.numeric)
+}
+
+// AsBoolSlice returns the []bool value. Make sure that the Value's type is
+// BOOLSLICE.
+func (v Value) AsBoolSlice() []bool {
+	if s, ok := v.slice.(*[]bool); ok {
+		return *s
+	}
+	return nil
+}
+
+// AsInt64 returns the int64 value. Make sure that the Value's type is
+// INT64.
+func (v Value) AsInt64() int64 {
+	return internal.RawToInt64(v.numeric)
+}
+
+// AsInt64Slice returns the []int64 value. Make sure that the Value's type is
+// INT64SLICE.
+func (v Value) AsInt64Slice() []int64 {
+	if s, ok := v.slice.(*[]int64); ok {
+		return *s
+	}
+	return nil
+}
+
+// AsFloat64 returns the float64 value. Make sure that the Value's
+// type is FLOAT64.
+func (v Value) AsFloat64() float64 {
+	return internal.RawToFloat64(v.numeric)
+}
+
+// AsFloat64Slice returns the []float64 value. Make sure that the Value's type is
+// FLOAT64SLICE.
+func (v Value) AsFloat64Slice() []float64 {
+	if s, ok := v.slice.(*[]float64); ok {
+		return *s
+	}
+	return nil
+}
+
+// AsString returns the string value. Make sure that the Value's type
+// is STRING.
+func (v Value) AsString() string {
+	return v.stringly
+}
+
+// AsStringSlice returns the []string value. Make sure that the Value's type is
+// STRINGSLICE.
+func (v Value) AsStringSlice() []string {
+	if s, ok := v.slice.(*[]string); ok {
+		return *s
+	}
+	return nil
+}
+
+type unknownValueType struct{}
+
+// AsInterface returns Value's data as interface{}.
+func (v Value) AsInterface() interface{} {
+	switch v.Type() {
+	case BOOL:
+		return v.AsBool()
+	case BOOLSLICE:
+		return v.AsBoolSlice()
+	case INT64:
+		return v.AsInt64()
+	case INT64SLICE:
+		return v.AsInt64Slice()
+	case FLOAT64:
+		return v.AsFloat64()
+	case FLOAT64SLICE:
+		return v.AsFloat64Slice()
+	case STRING:
+		return v.stringly
+	case STRINGSLICE:
+		return v.AsStringSlice()
+	}
+	return unknownValueType{}
+}
+
+// Emit returns a string representation of Value's data.
+func (v Value) Emit() string {
+	switch v.Type() {
+	case BOOLSLICE:
+		return fmt.Sprint(*(v.slice.(*[]bool)))
+	case BOOL:
+		return strconv.FormatBool(v.AsBool())
+	case INT64SLICE:
+		return fmt.Sprint(*(v.slice.(*[]int64)))
+	case INT64:
+		return strconv.FormatInt(v.AsInt64(), 10)
+	case FLOAT64SLICE:
+		return fmt.Sprint(*(v.slice.(*[]float64)))
+	case FLOAT64:
+		return fmt.Sprint(v.AsFloat64())
+	case STRINGSLICE:
+		return fmt.Sprint(*(v.slice.(*[]string)))
+	case STRING:
+		return v.stringly
+	default:
+		return "unknown"
+	}
+}
+
+// MarshalJSON returns the JSON encoding of the Value.
+func (v Value) MarshalJSON() ([]byte, error) {
+	var jsonVal struct {
+		Type  string
+		Value interface{}
+	}
+	jsonVal.Type = v.Type().String()
+	jsonVal.Value = v.AsInterface()
+	return json.Marshal(jsonVal)
+}

vendor/go.opentelemetry.io/otel/baggage/baggage.go

@@ -0,0 +1,556 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package baggage // import "go.opentelemetry.io/otel/baggage"
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+	"regexp"
+	"strings"
+
+	"go.opentelemetry.io/otel/internal/baggage"
+)
+
+const (
+	maxMembers               = 180
+	maxBytesPerMembers       = 4096
+	maxBytesPerBaggageString = 8192
+
+	listDelimiter     = ","
+	keyValueDelimiter = "="
+	propertyDelimiter = ";"
+
+	keyDef      = `([\x21\x23-\x27\x2A\x2B\x2D\x2E\x30-\x39\x41-\x5a\x5e-\x7a\x7c\x7e]+)`
+	valueDef    = `([\x21\x23-\x2b\x2d-\x3a\x3c-\x5B\x5D-\x7e]*)`
+	keyValueDef = `\s*` + keyDef + `\s*` + keyValueDelimiter + `\s*` + valueDef + `\s*`
+)
+
+var (
+	keyRe      = regexp.MustCompile(`^` + keyDef + `$`)
+	valueRe    = regexp.MustCompile(`^` + valueDef + `$`)
+	propertyRe = regexp.MustCompile(`^(?:\s*` + keyDef + `\s*|` + keyValueDef + `)$`)
+)
+
+var (
+	errInvalidKey      = errors.New("invalid key")
+	errInvalidValue    = errors.New("invalid value")
+	errInvalidProperty = errors.New("invalid baggage list-member property")
+	errInvalidMember   = errors.New("invalid baggage list-member")
+	errMemberNumber    = errors.New("too many list-members in baggage-string")
+	errMemberBytes     = errors.New("list-member too large")
+	errBaggageBytes    = errors.New("baggage-string too large")
+)
+
+// Property is an additional metadata entry for a baggage list-member.
+type Property struct {
+	key, value string
+
+	// hasValue indicates if a zero-value value means the property does not
+	// have a value or if it was the zero-value.
+	hasValue bool
+
+	// hasData indicates whether the created property contains data or not.
+	// Properties that do not contain data are invalid with no other check
+	// required.
+	hasData bool
+}
+
+func NewKeyProperty(key string) (Property, error) {
+	if !keyRe.MatchString(key) {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
+	}
+
+	p := Property{key: key, hasData: true}
+	return p, nil
+}
+
+func NewKeyValueProperty(key, value string) (Property, error) {
+	if !keyRe.MatchString(key) {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
+	}
+	if !valueRe.MatchString(value) {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
+	}
+
+	p := Property{
+		key:      key,
+		value:    value,
+		hasValue: true,
+		hasData:  true,
+	}
+	return p, nil
+}
+
+func newInvalidProperty() Property {
+	return Property{}
+}
+
+// parseProperty attempts to decode a Property from the passed string. It
+// returns an error if the input is invalid according to the W3C Baggage
+// specification.
+func parseProperty(property string) (Property, error) {
+	if property == "" {
+		return newInvalidProperty(), nil
+	}
+
+	match := propertyRe.FindStringSubmatch(property)
+	if len(match) != 4 {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidProperty, property)
+	}
+
+	p := Property{hasData: true}
+	if match[1] != "" {
+		p.key = match[1]
+	} else {
+		p.key = match[2]
+		p.value = match[3]
+		p.hasValue = true
+	}
+
+	return p, nil
+}
+
+// validate ensures p conforms to the W3C Baggage specification, returning an
+// error otherwise.
+func (p Property) validate() error {
+	errFunc := func(err error) error {
+		return fmt.Errorf("invalid property: %w", err)
+	}
+
+	if !p.hasData {
+		return errFunc(fmt.Errorf("%w: %q", errInvalidProperty, p))
+	}
+
+	if !keyRe.MatchString(p.key) {
+		return errFunc(fmt.Errorf("%w: %q", errInvalidKey, p.key))
+	}
+	if p.hasValue && !valueRe.MatchString(p.value) {
+		return errFunc(fmt.Errorf("%w: %q", errInvalidValue, p.value))
+	}
+	if !p.hasValue && p.value != "" {
+		return errFunc(errors.New("inconsistent value"))
+	}
+	return nil
+}
+
+// Key returns the Property key.
+func (p Property) Key() string {
+	return p.key
+}
+
+// Value returns the Property value. Additionally a boolean value is returned
+// indicating if the returned value is the empty if the Property has a value
+// that is empty or if the value is not set.
+func (p Property) Value() (string, bool) {
+	return p.value, p.hasValue
+}
+
+// String encodes Property into a string compliant with the W3C Baggage
+// specification.
+func (p Property) String() string {
+	if p.hasValue {
+		return fmt.Sprintf("%s%s%v", p.key, keyValueDelimiter, p.value)
+	}
+	return p.key
+}
+
+type properties []Property
+
+func fromInternalProperties(iProps []baggage.Property) properties {
+	if len(iProps) == 0 {
+		return nil
+	}
+
+	props := make(properties, len(iProps))
+	for i, p := range iProps {
+		props[i] = Property{
+			key:      p.Key,
+			value:    p.Value,
+			hasValue: p.HasValue,
+		}
+	}
+	return props
+}
+
+func (p properties) asInternal() []baggage.Property {
+	if len(p) == 0 {
+		return nil
+	}
+
+	iProps := make([]baggage.Property, len(p))
+	for i, prop := range p {
+		iProps[i] = baggage.Property{
+			Key:      prop.key,
+			Value:    prop.value,
+			HasValue: prop.hasValue,
+		}
+	}
+	return iProps
+}
+
+func (p properties) Copy() properties {
+	if len(p) == 0 {
+		return nil
+	}
+
+	props := make(properties, len(p))
+	copy(props, p)
+	return props
+}
+
+// validate ensures each Property in p conforms to the W3C Baggage
+// specification, returning an error otherwise.
+func (p properties) validate() error {
+	for _, prop := range p {
+		if err := prop.validate(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// String encodes properties into a string compliant with the W3C Baggage
+// specification.
+func (p properties) String() string {
+	props := make([]string, len(p))
+	for i, prop := range p {
+		props[i] = prop.String()
+	}
+	return strings.Join(props, propertyDelimiter)
+}
+
+// Member is a list-member of a baggage-string as defined by the W3C Baggage
+// specification.
+type Member struct {
+	key, value string
+	properties properties
+
+	// hasData indicates whether the created property contains data or not.
+	// Properties that do not contain data are invalid with no other check
+	// required.
+	hasData bool
+}
+
+// NewMember returns a new Member from the passed arguments. An error is
+// returned if the created Member would be invalid according to the W3C
+// Baggage specification.
+func NewMember(key, value string, props ...Property) (Member, error) {
+	m := Member{
+		key:        key,
+		value:      value,
+		properties: properties(props).Copy(),
+		hasData:    true,
+	}
+	if err := m.validate(); err != nil {
+		return newInvalidMember(), err
+	}
+
+	return m, nil
+}
+
+func newInvalidMember() Member {
+	return Member{}
+}
+
+// parseMember attempts to decode a Member from the passed string. It returns
+// an error if the input is invalid according to the W3C Baggage
+// specification.
+func parseMember(member string) (Member, error) {
+	if n := len(member); n > maxBytesPerMembers {
+		return newInvalidMember(), fmt.Errorf("%w: %d", errMemberBytes, n)
+	}
+
+	var (
+		key, value string
+		props      properties
+	)
+
+	parts := strings.SplitN(member, propertyDelimiter, 2)
+	switch len(parts) {
+	case 2:
+		// Parse the member properties.
+		for _, pStr := range strings.Split(parts[1], propertyDelimiter) {
+			p, err := parseProperty(pStr)
+			if err != nil {
+				return newInvalidMember(), err
+			}
+			props = append(props, p)
+		}
+		fallthrough
+	case 1:
+		// Parse the member key/value pair.
+
+		// Take into account a value can contain equal signs (=).
+		kv := strings.SplitN(parts[0], keyValueDelimiter, 2)
+		if len(kv) != 2 {
+			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidMember, member)
+		}
+		// "Leading and trailing whitespaces are allowed but MUST be trimmed
+		// when converting the header into a data structure."
+		key = strings.TrimSpace(kv[0])
+		var err error
+		value, err = url.QueryUnescape(strings.TrimSpace(kv[1]))
+		if err != nil {
+			return newInvalidMember(), fmt.Errorf("%w: %q", err, value)
+		}
+		if !keyRe.MatchString(key) {
+			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidKey, key)
+		}
+		if !valueRe.MatchString(value) {
+			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
+		}
+	default:
+		// This should never happen unless a developer has changed the string
+		// splitting somehow. Panic instead of failing silently and allowing
+		// the bug to slip past the CI checks.
+		panic("failed to parse baggage member")
+	}
+
+	return Member{key: key, value: value, properties: props, hasData: true}, nil
+}
+
+// validate ensures m conforms to the W3C Baggage specification, returning an
+// error otherwise.
+func (m Member) validate() error {
+	if !m.hasData {
+		return fmt.Errorf("%w: %q", errInvalidMember, m)
+	}
+
+	if !keyRe.MatchString(m.key) {
+		return fmt.Errorf("%w: %q", errInvalidKey, m.key)
+	}
+	if !valueRe.MatchString(m.value) {
+		return fmt.Errorf("%w: %q", errInvalidValue, m.value)
+	}
+	return m.properties.validate()
+}
+
+// Key returns the Member key.
+func (m Member) Key() string { return m.key }
+
+// Value returns the Member value.
+func (m Member) Value() string { return m.value }
+
+// Properties returns a copy of the Member properties.
+func (m Member) Properties() []Property { return m.properties.Copy() }
+
+// String encodes Member into a string compliant with the W3C Baggage
+// specification.
+func (m Member) String() string {
+	// A key is just an ASCII string, but a value is URL encoded UTF-8.
+	s := fmt.Sprintf("%s%s%s", m.key, keyValueDelimiter, url.QueryEscape(m.value))
+	if len(m.properties) > 0 {
+		s = fmt.Sprintf("%s%s%s", s, propertyDelimiter, m.properties.String())
+	}
+	return s
+}
+
+// Baggage is a list of baggage members representing the baggage-string as
+// defined by the W3C Baggage specification.
+type Baggage struct { //nolint:golint
+	list baggage.List
+}
+
+// New returns a new valid Baggage. It returns an error if it results in a
+// Baggage exceeding limits set in that specification.
+//
+// It expects all the provided members to have already been validated.
+func New(members ...Member) (Baggage, error) {
+	if len(members) == 0 {
+		return Baggage{}, nil
+	}
+
+	b := make(baggage.List)
+	for _, m := range members {
+		if !m.hasData {
+			return Baggage{}, errInvalidMember
+		}
+
+		// OpenTelemetry resolves duplicates by last-one-wins.
+		b[m.key] = baggage.Item{
+			Value:      m.value,
+			Properties: m.properties.asInternal(),
+		}
+	}
+
+	// Check member numbers after deduplicating.
+	if len(b) > maxMembers {
+		return Baggage{}, errMemberNumber
+	}
+
+	bag := Baggage{b}
+	if n := len(bag.String()); n > maxBytesPerBaggageString {
+		return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
+	}
+
+	return bag, nil
+}
+
+// Parse attempts to decode a baggage-string from the passed string. It
+// returns an error if the input is invalid according to the W3C Baggage
+// specification.
+//
+// If there are duplicate list-members contained in baggage, the last one
+// defined (reading left-to-right) will be the only one kept. This diverges
+// from the W3C Baggage specification which allows duplicate list-members, but
+// conforms to the OpenTelemetry Baggage specification.
+func Parse(bStr string) (Baggage, error) {
+	if bStr == "" {
+		return Baggage{}, nil
+	}
+
+	if n := len(bStr); n > maxBytesPerBaggageString {
+		return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
+	}
+
+	b := make(baggage.List)
+	for _, memberStr := range strings.Split(bStr, listDelimiter) {
+		m, err := parseMember(memberStr)
+		if err != nil {
+			return Baggage{}, err
+		}
+		// OpenTelemetry resolves duplicates by last-one-wins.
+		b[m.key] = baggage.Item{
+			Value:      m.value,
+			Properties: m.properties.asInternal(),
+		}
+	}
+
+	// OpenTelemetry does not allow for duplicate list-members, but the W3C
+	// specification does. Now that we have deduplicated, ensure the baggage
+	// does not exceed list-member limits.
+	if len(b) > maxMembers {
+		return Baggage{}, errMemberNumber
+	}
+
+	return Baggage{b}, nil
+}
+
+// Member returns the baggage list-member identified by key.
+//
+// If there is no list-member matching the passed key the returned Member will
+// be a zero-value Member.
+// The returned member is not validated, as we assume the validation happened
+// when it was added to the Baggage.
+func (b Baggage) Member(key string) Member {
+	v, ok := b.list[key]
+	if !ok {
+		// We do not need to worry about distiguising between the situation
+		// where a zero-valued Member is included in the Baggage because a
+		// zero-valued Member is invalid according to the W3C Baggage
+		// specification (it has an empty key).
+		return newInvalidMember()
+	}
+
+	return Member{
+		key:        key,
+		value:      v.Value,
+		properties: fromInternalProperties(v.Properties),
+	}
+}
+
+// Members returns all the baggage list-members.
+// The order of the returned list-members does not have significance.
+//
+// The returned members are not validated, as we assume the validation happened
+// when they were added to the Baggage.
+func (b Baggage) Members() []Member {
+	if len(b.list) == 0 {
+		return nil
+	}
+
+	members := make([]Member, 0, len(b.list))
+	for k, v := range b.list {
+		members = append(members, Member{
+			key:        k,
+			value:      v.Value,
+			properties: fromInternalProperties(v.Properties),
+		})
+	}
+	return members
+}
+
+// SetMember returns a copy the Baggage with the member included. If the
+// baggage contains a Member with the same key the existing Member is
+// replaced.
+//
+// If member is invalid according to the W3C Baggage specification, an error
+// is returned with the original Baggage.
+func (b Baggage) SetMember(member Member) (Baggage, error) {
+	if !member.hasData {
+		return b, errInvalidMember
+	}
+
+	n := len(b.list)
+	if _, ok := b.list[member.key]; !ok {
+		n++
+	}
+	list := make(baggage.List, n)
+
+	for k, v := range b.list {
+		// Do not copy if we are just going to overwrite.
+		if k == member.key {
+			continue
+		}
+		list[k] = v
+	}
+
+	list[member.key] = baggage.Item{
+		Value:      member.value,
+		Properties: member.properties.asInternal(),
+	}
+
+	return Baggage{list: list}, nil
+}
+
+// DeleteMember returns a copy of the Baggage with the list-member identified
+// by key removed.
+func (b Baggage) DeleteMember(key string) Baggage {
+	n := len(b.list)
+	if _, ok := b.list[key]; ok {
+		n--
+	}
+	list := make(baggage.List, n)
+
+	for k, v := range b.list {
+		if k == key {
+			continue
+		}
+		list[k] = v
+	}
+
+	return Baggage{list: list}
+}
+
+// Len returns the number of list-members in the Baggage.
+func (b Baggage) Len() int {
+	return len(b.list)
+}
+
+// String encodes Baggage into a string compliant with the W3C Baggage
+// specification. The returned string will be invalid if the Baggage contains
+// any invalid list-members.
+func (b Baggage) String() string {
+	members := make([]string, 0, len(b.list))
+	for k, v := range b.list {
+		members = append(members, Member{
+			key:        k,
+			value:      v.Value,
+			properties: fromInternalProperties(v.Properties),
+		}.String())
+	}
+	return strings.Join(members, listDelimiter)
+}

vendor/go.opentelemetry.io/otel/baggage/context.go

@@ -0,0 +1,39 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package baggage // import "go.opentelemetry.io/otel/baggage"
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/internal/baggage"
+)
+
+// ContextWithBaggage returns a copy of parent with baggage.
+func ContextWithBaggage(parent context.Context, b Baggage) context.Context {
+	// Delegate so any hooks for the OpenTracing bridge are handled.
+	return baggage.ContextWithList(parent, b.list)
+}
+
+// ContextWithoutBaggage returns a copy of parent with no baggage.
+func ContextWithoutBaggage(parent context.Context) context.Context {
+	// Delegate so any hooks for the OpenTracing bridge are handled.
+	return baggage.ContextWithList(parent, nil)
+}
+
+// FromContext returns the baggage contained in ctx.
+func FromContext(ctx context.Context) Baggage {
+	// Delegate so any hooks for the OpenTracing bridge are handled.
+	return Baggage{list: baggage.ListFromContext(ctx)}
+}

vendor/go.opentelemetry.io/otel/baggage/doc.go

@@ -0,0 +1,20 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package baggage provides functionality for storing and retrieving
+baggage items in Go context. For propagating the baggage, see the
+go.opentelemetry.io/otel/propagation package.
+*/
+package baggage // import "go.opentelemetry.io/otel/baggage"

vendor/go.opentelemetry.io/otel/codes/codes.go

@@ -0,0 +1,106 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package codes // import "go.opentelemetry.io/otel/codes"
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+)
+
+const (
+	// Unset is the default status code.
+	Unset Code = 0
+	// Error indicates the operation contains an error.
+	Error Code = 1
+	// Ok indicates operation has been validated by an Application developers
+	// or Operator to have completed successfully, or contain no error.
+	Ok Code = 2
+
+	maxCode = 3
+)
+
+// Code is an 32-bit representation of a status state.
+type Code uint32
+
+var codeToStr = map[Code]string{
+	Unset: "Unset",
+	Error: "Error",
+	Ok:    "Ok",
+}
+
+var strToCode = map[string]Code{
+	`"Unset"`: Unset,
+	`"Error"`: Error,
+	`"Ok"`:    Ok,
+}
+
+// String returns the Code as a string.
+func (c Code) String() string {
+	return codeToStr[c]
+}
+
+// UnmarshalJSON unmarshals b into the Code.
+//
+// This is based on the functionality in the gRPC codes package:
+// https://github.com/grpc/grpc-go/blob/bb64fee312b46ebee26be43364a7a966033521b1/codes/codes.go#L218-L244
+func (c *Code) UnmarshalJSON(b []byte) error {
+	// From json.Unmarshaler: By convention, to approximate the behavior of
+	// Unmarshal itself, Unmarshalers implement UnmarshalJSON([]byte("null")) as
+	// a no-op.
+	if string(b) == "null" {
+		return nil
+	}
+	if c == nil {
+		return fmt.Errorf("nil receiver passed to UnmarshalJSON")
+	}
+
+	var x interface{}
+	if err := json.Unmarshal(b, &x); err != nil {
+		return err
+	}
+	switch x.(type) {
+	case string:
+		if jc, ok := strToCode[string(b)]; ok {
+			*c = jc
+			return nil
+		}
+		return fmt.Errorf("invalid code: %q", string(b))
+	case float64:
+		if ci, err := strconv.ParseUint(string(b), 10, 32); err == nil {
+			if ci >= maxCode {
+				return fmt.Errorf("invalid code: %q", ci)
+			}
+
+			*c = Code(ci)
+			return nil
+		}
+		return fmt.Errorf("invalid code: %q", string(b))
+	default:
+		return fmt.Errorf("invalid code: %q", string(b))
+	}
+}
+
+// MarshalJSON returns c as the JSON encoding of c.
+func (c *Code) MarshalJSON() ([]byte, error) {
+	if c == nil {
+		return []byte("null"), nil
+	}
+	str, ok := codeToStr[*c]
+	if !ok {
+		return nil, fmt.Errorf("invalid code: %d", *c)
+	}
+	return []byte(fmt.Sprintf("%q", str)), nil
+}

vendor/go.opentelemetry.io/otel/codes/doc.go

@@ -0,0 +1,21 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package codes defines the canonical error codes used by OpenTelemetry.
+
+It conforms to [the OpenTelemetry
+specification](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/api.md#statuscanonicalcode).
+*/
+package codes // import "go.opentelemetry.io/otel/codes"

vendor/go.opentelemetry.io/otel/doc.go

@@ -0,0 +1,34 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package otel provides global access to the OpenTelemetry API. The subpackages of
+the otel package provide an implementation of the OpenTelemetry API.
+
+The provided API is used to instrument code and measure data about that code's
+performance and operation. The measured data, by default, is not processed or
+transmitted anywhere. An implementation of the OpenTelemetry SDK, like the
+default SDK implementation (go.opentelemetry.io/otel/sdk), and associated
+exporters are used to process and transport this data.
+
+To read the getting started guide, see https://opentelemetry.io/docs/go/getting-started/.
+
+To read more about tracing, see go.opentelemetry.io/otel/trace.
+
+To read more about metrics, see go.opentelemetry.io/otel/metric.
+
+To read more about propagation, see go.opentelemetry.io/otel/propagation and
+go.opentelemetry.io/otel/baggage.
+*/
+package otel // import "go.opentelemetry.io/otel"

vendor/go.opentelemetry.io/otel/error_handler.go

@@ -0,0 +1,38 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otel // import "go.opentelemetry.io/otel"
+
+// ErrorHandler handles irremediable events.
+type ErrorHandler interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Handle handles any error deemed irremediable by an OpenTelemetry
+	// component.
+	Handle(error)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+// ErrorHandlerFunc is a convenience adapter to allow the use of a function
+// as an ErrorHandler.
+type ErrorHandlerFunc func(error)
+
+var _ ErrorHandler = ErrorHandlerFunc(nil)
+
+// Handle handles the irremediable error by calling the ErrorHandlerFunc itself.
+func (f ErrorHandlerFunc) Handle(err error) {
+	f(err)
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
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+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
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+      the terms of any separate license agreement you may have executed
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+
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+
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+   Copyright [yyyy] [name of copyright owner]
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+   you may not use this file except in compliance with the License.
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+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/README.md

@@ -0,0 +1,51 @@
+# OpenTelemetry-Go OTLP Span Exporter
+
+[![Go Reference](https://pkg.go.dev/badge/go.opentelemetry.io/otel/exporters/otlp/otlptrace.svg)](https://pkg.go.dev/go.opentelemetry.io/otel/exporters/otlp/otlptrace)
+
+[OpenTelemetry Protocol Exporter](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.5.0/specification/protocol/exporter.md) implementation.
+
+## Installation
+
+```
+go get -u go.opentelemetry.io/otel/exporters/otlp/otlptrace
+```
+
+## Examples
+
+- [Exporter setup and examples](./otlptracehttp/example_test.go)
+- [Full example sending telemetry to a local collector](../../../example/otel-collector)
+
+## [`otlptrace`](https://pkg.go.dev/go.opentelemetry.io/otel/exporters/otlp/otlptrace)
+
+The `otlptrace` package provides an exporter implementing the OTel span exporter interface.
+This exporter is configured using a client satisfying the `otlptrace.Client` interface.
+This client handles the transformation of data into wire format and the transmission of that data to the collector.
+
+## [`otlptracegrpc`](https://pkg.go.dev/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc)
+
+The `otlptracegrpc` package implements a client for the span exporter that sends trace telemetry data to the collector using gRPC with protobuf-encoded payloads.
+
+## [`otlptracehttp`](https://pkg.go.dev/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp)
+
+The `otlptracehttp` package implements a client for the span exporter that sends trace telemetry data to the collector using HTTP with protobuf-encoded payloads.
+
+## Configuration
+
+### Environment Variables
+
+The following environment variables can be used (instead of options objects) to
+override the default configuration. For more information about how each of
+these environment variables is interpreted, see [the OpenTelemetry
+specification](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.8.0/specification/protocol/exporter.md).
+
+| Environment variable                                                     | Option                        | Default value                                            |
+| ------------------------------------------------------------------------ |------------------------------ | -------------------------------------------------------- |
+| `OTEL_EXPORTER_OTLP_ENDPOINT` `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT`       | `WithEndpoint` `WithInsecure` | `https://localhost:4317` or `https://localhost:4318`[^1] |
+| `OTEL_EXPORTER_OTLP_CERTIFICATE` `OTEL_EXPORTER_OTLP_TRACES_CERTIFICATE` | `WithTLSClientConfig`         |                                                          |
+| `OTEL_EXPORTER_OTLP_HEADERS` `OTEL_EXPORTER_OTLP_TRACES_HEADERS`         | `WithHeaders`                 |                                                          |
+| `OTEL_EXPORTER_OTLP_COMPRESSION` `OTEL_EXPORTER_OTLP_TRACES_COMPRESSION` | `WithCompression`             |                                                          |
+| `OTEL_EXPORTER_OTLP_TIMEOUT` `OTEL_EXPORTER_OTLP_TRACES_TIMEOUT`         | `WithTimeout`                 | `10s`                                                    |
+
+[^1]: The gRPC client defaults to `https://localhost:4317` and the HTTP client `https://localhost:4318`.
+
+Configuration using options have precedence over the environment variables.

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/clients.go

@@ -0,0 +1,54 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otlptrace // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace"
+
+import (
+	"context"
+
+	tracepb "go.opentelemetry.io/proto/otlp/trace/v1"
+)
+
+// Client manages connections to the collector, handles the
+// transformation of data into wire format, and the transmission of that
+// data to the collector.
+type Client interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Start should establish connection(s) to endpoint(s). It is
+	// called just once by the exporter, so the implementation
+	// does not need to worry about idempotence and locking.
+	Start(ctx context.Context) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Stop should close the connections. The function is called
+	// only once by the exporter, so the implementation does not
+	// need to worry about idempotence, but it may be called
+	// concurrently with UploadTraces, so proper
+	// locking is required. The function serves as a
+	// synchronization point - after the function returns, the
+	// process of closing connections is assumed to be finished.
+	Stop(ctx context.Context) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// UploadTraces should transform the passed traces to the wire
+	// format and send it to the collector. May be called
+	// concurrently.
+	UploadTraces(ctx context.Context, protoSpans []*tracepb.ResourceSpans) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/exporter.go

@@ -0,0 +1,113 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otlptrace // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace"
+
+import (
+	"context"
+	"errors"
+	"sync"
+
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
+	tracesdk "go.opentelemetry.io/otel/sdk/trace"
+)
+
+var (
+	errAlreadyStarted = errors.New("already started")
+)
+
+// Exporter exports trace data in the OTLP wire format.
+type Exporter struct {
+	client Client
+
+	mu      sync.RWMutex
+	started bool
+
+	startOnce sync.Once
+	stopOnce  sync.Once
+}
+
+// ExportSpans exports a batch of spans.
+func (e *Exporter) ExportSpans(ctx context.Context, ss []tracesdk.ReadOnlySpan) error {
+	protoSpans := tracetransform.Spans(ss)
+	if len(protoSpans) == 0 {
+		return nil
+	}
+
+	return e.client.UploadTraces(ctx, protoSpans)
+}
+
+// Start establishes a connection to the receiving endpoint.
+func (e *Exporter) Start(ctx context.Context) error {
+	var err = errAlreadyStarted
+	e.startOnce.Do(func() {
+		e.mu.Lock()
+		e.started = true
+		e.mu.Unlock()
+		err = e.client.Start(ctx)
+	})
+
+	return err
+}
+
+// Shutdown flushes all exports and closes all connections to the receiving endpoint.
+func (e *Exporter) Shutdown(ctx context.Context) error {
+	e.mu.RLock()
+	started := e.started
+	e.mu.RUnlock()
+
+	if !started {
+		return nil
+	}
+
+	var err error
+
+	e.stopOnce.Do(func() {
+		err = e.client.Stop(ctx)
+		e.mu.Lock()
+		e.started = false
+		e.mu.Unlock()
+	})
+
+	return err
+}
+
+var _ tracesdk.SpanExporter = (*Exporter)(nil)
+
+// New constructs a new Exporter and starts it.
+func New(ctx context.Context, client Client) (*Exporter, error) {
+	exp := NewUnstarted(client)
+	if err := exp.Start(ctx); err != nil {
+		return nil, err
+	}
+	return exp, nil
+}
+
+// NewUnstarted constructs a new Exporter and does not start it.
+func NewUnstarted(client Client) *Exporter {
+	return &Exporter{
+		client: client,
+	}
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this exporter.
+func (e *Exporter) MarshalLog() interface{} {
+	return struct {
+		Type   string
+		Client Client
+	}{
+		Type:   "otlptrace",
+		Client: e.client,
+	}
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform/attribute.go

@@ -0,0 +1,158 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tracetransform // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
+
+import (
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/resource"
+	commonpb "go.opentelemetry.io/proto/otlp/common/v1"
+)
+
+// KeyValues transforms a slice of attribute KeyValues into OTLP key-values.
+func KeyValues(attrs []attribute.KeyValue) []*commonpb.KeyValue {
+	if len(attrs) == 0 {
+		return nil
+	}
+
+	out := make([]*commonpb.KeyValue, 0, len(attrs))
+	for _, kv := range attrs {
+		out = append(out, KeyValue(kv))
+	}
+	return out
+}
+
+// Iterator transforms an attribute iterator into OTLP key-values.
+func Iterator(iter attribute.Iterator) []*commonpb.KeyValue {
+	l := iter.Len()
+	if l == 0 {
+		return nil
+	}
+
+	out := make([]*commonpb.KeyValue, 0, l)
+	for iter.Next() {
+		out = append(out, KeyValue(iter.Attribute()))
+	}
+	return out
+}
+
+// ResourceAttributes transforms a Resource OTLP key-values.
+func ResourceAttributes(resource *resource.Resource) []*commonpb.KeyValue {
+	return Iterator(resource.Iter())
+}
+
+// KeyValue transforms an attribute KeyValue into an OTLP key-value.
+func KeyValue(kv attribute.KeyValue) *commonpb.KeyValue {
+	return &commonpb.KeyValue{Key: string(kv.Key), Value: Value(kv.Value)}
+}
+
+// Value transforms an attribute Value into an OTLP AnyValue.
+func Value(v attribute.Value) *commonpb.AnyValue {
+	av := new(commonpb.AnyValue)
+	switch v.Type() {
+	case attribute.BOOL:
+		av.Value = &commonpb.AnyValue_BoolValue{
+			BoolValue: v.AsBool(),
+		}
+	case attribute.BOOLSLICE:
+		av.Value = &commonpb.AnyValue_ArrayValue{
+			ArrayValue: &commonpb.ArrayValue{
+				Values: boolSliceValues(v.AsBoolSlice()),
+			},
+		}
+	case attribute.INT64:
+		av.Value = &commonpb.AnyValue_IntValue{
+			IntValue: v.AsInt64(),
+		}
+	case attribute.INT64SLICE:
+		av.Value = &commonpb.AnyValue_ArrayValue{
+			ArrayValue: &commonpb.ArrayValue{
+				Values: int64SliceValues(v.AsInt64Slice()),
+			},
+		}
+	case attribute.FLOAT64:
+		av.Value = &commonpb.AnyValue_DoubleValue{
+			DoubleValue: v.AsFloat64(),
+		}
+	case attribute.FLOAT64SLICE:
+		av.Value = &commonpb.AnyValue_ArrayValue{
+			ArrayValue: &commonpb.ArrayValue{
+				Values: float64SliceValues(v.AsFloat64Slice()),
+			},
+		}
+	case attribute.STRING:
+		av.Value = &commonpb.AnyValue_StringValue{
+			StringValue: v.AsString(),
+		}
+	case attribute.STRINGSLICE:
+		av.Value = &commonpb.AnyValue_ArrayValue{
+			ArrayValue: &commonpb.ArrayValue{
+				Values: stringSliceValues(v.AsStringSlice()),
+			},
+		}
+	default:
+		av.Value = &commonpb.AnyValue_StringValue{
+			StringValue: "INVALID",
+		}
+	}
+	return av
+}
+
+func boolSliceValues(vals []bool) []*commonpb.AnyValue {
+	converted := make([]*commonpb.AnyValue, len(vals))
+	for i, v := range vals {
+		converted[i] = &commonpb.AnyValue{
+			Value: &commonpb.AnyValue_BoolValue{
+				BoolValue: v,
+			},
+		}
+	}
+	return converted
+}
+
+func int64SliceValues(vals []int64) []*commonpb.AnyValue {
+	converted := make([]*commonpb.AnyValue, len(vals))
+	for i, v := range vals {
+		converted[i] = &commonpb.AnyValue{
+			Value: &commonpb.AnyValue_IntValue{
+				IntValue: v,
+			},
+		}
+	}
+	return converted
+}
+
+func float64SliceValues(vals []float64) []*commonpb.AnyValue {
+	converted := make([]*commonpb.AnyValue, len(vals))
+	for i, v := range vals {
+		converted[i] = &commonpb.AnyValue{
+			Value: &commonpb.AnyValue_DoubleValue{
+				DoubleValue: v,
+			},
+		}
+	}
+	return converted
+}
+
+func stringSliceValues(vals []string) []*commonpb.AnyValue {
+	converted := make([]*commonpb.AnyValue, len(vals))
+	for i, v := range vals {
+		converted[i] = &commonpb.AnyValue{
+			Value: &commonpb.AnyValue_StringValue{
+				StringValue: v,
+			},
+		}
+	}
+	return converted
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform/instrumentation.go

@@ -0,0 +1,30 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tracetransform // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
+
+import (
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	commonpb "go.opentelemetry.io/proto/otlp/common/v1"
+)
+
+func InstrumentationScope(il instrumentation.Library) *commonpb.InstrumentationScope {
+	if il == (instrumentation.Library{}) {
+		return nil
+	}
+	return &commonpb.InstrumentationScope{
+		Name:    il.Name,
+		Version: il.Version,
+	}
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform/resource.go

@@ -0,0 +1,28 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tracetransform // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
+
+import (
+	"go.opentelemetry.io/otel/sdk/resource"
+	resourcepb "go.opentelemetry.io/proto/otlp/resource/v1"
+)
+
+// Resource transforms a Resource into an OTLP Resource.
+func Resource(r *resource.Resource) *resourcepb.Resource {
+	if r == nil {
+		return nil
+	}
+	return &resourcepb.Resource{Attributes: ResourceAttributes(r)}
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform/span.go

@@ -0,0 +1,205 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tracetransform // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
+
+import (
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	tracesdk "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/trace"
+	tracepb "go.opentelemetry.io/proto/otlp/trace/v1"
+)
+
+// Spans transforms a slice of OpenTelemetry spans into a slice of OTLP
+// ResourceSpans.
+func Spans(sdl []tracesdk.ReadOnlySpan) []*tracepb.ResourceSpans {
+	if len(sdl) == 0 {
+		return nil
+	}
+
+	rsm := make(map[attribute.Distinct]*tracepb.ResourceSpans)
+
+	type key struct {
+		r  attribute.Distinct
+		il instrumentation.Library
+	}
+	ssm := make(map[key]*tracepb.ScopeSpans)
+
+	var resources int
+	for _, sd := range sdl {
+		if sd == nil {
+			continue
+		}
+
+		rKey := sd.Resource().Equivalent()
+		k := key{
+			r:  rKey,
+			il: sd.InstrumentationLibrary(),
+		}
+		scopeSpan, iOk := ssm[k]
+		if !iOk {
+			// Either the resource or instrumentation library were unknown.
+			scopeSpan = &tracepb.ScopeSpans{
+				Scope:     InstrumentationScope(sd.InstrumentationLibrary()),
+				Spans:     []*tracepb.Span{},
+				SchemaUrl: sd.InstrumentationLibrary().SchemaURL,
+			}
+		}
+		scopeSpan.Spans = append(scopeSpan.Spans, span(sd))
+		ssm[k] = scopeSpan
+
+		rs, rOk := rsm[rKey]
+		if !rOk {
+			resources++
+			// The resource was unknown.
+			rs = &tracepb.ResourceSpans{
+				Resource:   Resource(sd.Resource()),
+				ScopeSpans: []*tracepb.ScopeSpans{scopeSpan},
+				SchemaUrl:  sd.Resource().SchemaURL(),
+			}
+			rsm[rKey] = rs
+			continue
+		}
+
+		// The resource has been seen before. Check if the instrumentation
+		// library lookup was unknown because if so we need to add it to the
+		// ResourceSpans. Otherwise, the instrumentation library has already
+		// been seen and the append we did above will be included it in the
+		// ScopeSpans reference.
+		if !iOk {
+			rs.ScopeSpans = append(rs.ScopeSpans, scopeSpan)
+		}
+	}
+
+	// Transform the categorized map into a slice
+	rss := make([]*tracepb.ResourceSpans, 0, resources)
+	for _, rs := range rsm {
+		rss = append(rss, rs)
+	}
+	return rss
+}
+
+// span transforms a Span into an OTLP span.
+func span(sd tracesdk.ReadOnlySpan) *tracepb.Span {
+	if sd == nil {
+		return nil
+	}
+
+	tid := sd.SpanContext().TraceID()
+	sid := sd.SpanContext().SpanID()
+
+	s := &tracepb.Span{
+		TraceId:                tid[:],
+		SpanId:                 sid[:],
+		TraceState:             sd.SpanContext().TraceState().String(),
+		Status:                 status(sd.Status().Code, sd.Status().Description),
+		StartTimeUnixNano:      uint64(sd.StartTime().UnixNano()),
+		EndTimeUnixNano:        uint64(sd.EndTime().UnixNano()),
+		Links:                  links(sd.Links()),
+		Kind:                   spanKind(sd.SpanKind()),
+		Name:                   sd.Name(),
+		Attributes:             KeyValues(sd.Attributes()),
+		Events:                 spanEvents(sd.Events()),
+		DroppedAttributesCount: uint32(sd.DroppedAttributes()),
+		DroppedEventsCount:     uint32(sd.DroppedEvents()),
+		DroppedLinksCount:      uint32(sd.DroppedLinks()),
+	}
+
+	if psid := sd.Parent().SpanID(); psid.IsValid() {
+		s.ParentSpanId = psid[:]
+	}
+
+	return s
+}
+
+// status transform a span code and message into an OTLP span status.
+func status(status codes.Code, message string) *tracepb.Status {
+	var c tracepb.Status_StatusCode
+	switch status {
+	case codes.Ok:
+		c = tracepb.Status_STATUS_CODE_OK
+	case codes.Error:
+		c = tracepb.Status_STATUS_CODE_ERROR
+	default:
+		c = tracepb.Status_STATUS_CODE_UNSET
+	}
+	return &tracepb.Status{
+		Code:    c,
+		Message: message,
+	}
+}
+
+// links transforms span Links to OTLP span links.
+func links(links []tracesdk.Link) []*tracepb.Span_Link {
+	if len(links) == 0 {
+		return nil
+	}
+
+	sl := make([]*tracepb.Span_Link, 0, len(links))
+	for _, otLink := range links {
+		// This redefinition is necessary to prevent otLink.*ID[:] copies
+		// being reused -- in short we need a new otLink per iteration.
+		otLink := otLink
+
+		tid := otLink.SpanContext.TraceID()
+		sid := otLink.SpanContext.SpanID()
+
+		sl = append(sl, &tracepb.Span_Link{
+			TraceId:                tid[:],
+			SpanId:                 sid[:],
+			Attributes:             KeyValues(otLink.Attributes),
+			DroppedAttributesCount: uint32(otLink.DroppedAttributeCount),
+		})
+	}
+	return sl
+}
+
+// spanEvents transforms span Events to an OTLP span events.
+func spanEvents(es []tracesdk.Event) []*tracepb.Span_Event {
+	if len(es) == 0 {
+		return nil
+	}
+
+	events := make([]*tracepb.Span_Event, len(es))
+	// Transform message events
+	for i := 0; i < len(es); i++ {
+		events[i] = &tracepb.Span_Event{
+			Name:                   es[i].Name,
+			TimeUnixNano:           uint64(es[i].Time.UnixNano()),
+			Attributes:             KeyValues(es[i].Attributes),
+			DroppedAttributesCount: uint32(es[i].DroppedAttributeCount),
+		}
+	}
+	return events
+}
+
+// spanKind transforms a SpanKind to an OTLP span kind.
+func spanKind(kind trace.SpanKind) tracepb.Span_SpanKind {
+	switch kind {
+	case trace.SpanKindInternal:
+		return tracepb.Span_SPAN_KIND_INTERNAL
+	case trace.SpanKindClient:
+		return tracepb.Span_SPAN_KIND_CLIENT
+	case trace.SpanKindServer:
+		return tracepb.Span_SPAN_KIND_SERVER
+	case trace.SpanKindProducer:
+		return tracepb.Span_SPAN_KIND_PRODUCER
+	case trace.SpanKindConsumer:
+		return tracepb.Span_SPAN_KIND_CONSUMER
+	default:
+		return tracepb.Span_SPAN_KIND_UNSPECIFIED
+	}
+}

vendor/go.opentelemetry.io/otel/get_main_pkgs.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -euo pipefail
+
+top_dir='.'
+if [[ $# -gt 0 ]]; then
+    top_dir="${1}"
+fi
+
+p=$(pwd)
+mod_dirs=()
+
+# Note `mapfile` does not exist in older bash versions:
+# https://stackoverflow.com/questions/41475261/need-alternative-to-readarray-mapfile-for-script-on-older-version-of-bash
+
+while IFS= read -r line; do
+    mod_dirs+=("$line")
+done < <(find "${top_dir}" -type f -name 'go.mod' -exec dirname {} \; | sort)
+
+for mod_dir in "${mod_dirs[@]}"; do
+    cd "${mod_dir}"
+
+    while IFS= read -r line; do
+        echo ".${line#${p}}"
+    done < <(go list --find -f '{{.Name}}|{{.Dir}}' ./... | grep '^main|' | cut -f 2- -d '|')
+    cd "${p}"
+done

vendor/go.opentelemetry.io/otel/handler.go

@@ -0,0 +1,98 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otel // import "go.opentelemetry.io/otel"
+
+import (
+	"log"
+	"os"
+	"sync"
+)
+
+var (
+	// globalErrorHandler provides an ErrorHandler that can be used
+	// throughout an OpenTelemetry instrumented project. When a user
+	// specified ErrorHandler is registered (`SetErrorHandler`) all calls to
+	// `Handle` and will be delegated to the registered ErrorHandler.
+	globalErrorHandler = defaultErrorHandler()
+
+	// Compile-time check that delegator implements ErrorHandler.
+	_ ErrorHandler = (*delegator)(nil)
+	// Compile-time check that errLogger implements ErrorHandler.
+	_ ErrorHandler = (*errLogger)(nil)
+)
+
+type delegator struct {
+	lock *sync.RWMutex
+	eh   ErrorHandler
+}
+
+func (d *delegator) Handle(err error) {
+	d.lock.RLock()
+	defer d.lock.RUnlock()
+	d.eh.Handle(err)
+}
+
+// setDelegate sets the ErrorHandler delegate.
+func (d *delegator) setDelegate(eh ErrorHandler) {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+	d.eh = eh
+}
+
+func defaultErrorHandler() *delegator {
+	return &delegator{
+		lock: &sync.RWMutex{},
+		eh:   &errLogger{l: log.New(os.Stderr, "", log.LstdFlags)},
+	}
+
+}
+
+// errLogger logs errors if no delegate is set, otherwise they are delegated.
+type errLogger struct {
+	l *log.Logger
+}
+
+// Handle logs err if no delegate is set, otherwise it is delegated.
+func (h *errLogger) Handle(err error) {
+	h.l.Print(err)
+}
+
+// GetErrorHandler returns the global ErrorHandler instance.
+//
+// The default ErrorHandler instance returned will log all errors to STDERR
+// until an override ErrorHandler is set with SetErrorHandler. All
+// ErrorHandler returned prior to this will automatically forward errors to
+// the set instance instead of logging.
+//
+// Subsequent calls to SetErrorHandler after the first will not forward errors
+// to the new ErrorHandler for prior returned instances.
+func GetErrorHandler() ErrorHandler {
+	return globalErrorHandler
+}
+
+// SetErrorHandler sets the global ErrorHandler to h.
+//
+// The first time this is called all ErrorHandler previously returned from
+// GetErrorHandler will send errors to h instead of the default logging
+// ErrorHandler. Subsequent calls will set the global ErrorHandler, but not
+// delegate errors to h.
+func SetErrorHandler(h ErrorHandler) {
+	globalErrorHandler.setDelegate(h)
+}
+
+// Handle is a convenience function for ErrorHandler().Handle(err)
+func Handle(err error) {
+	GetErrorHandler().Handle(err)
+}

vendor/go.opentelemetry.io/otel/internal/baggage/baggage.go

@@ -0,0 +1,43 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package baggage provides base types and functionality to store and retrieve
+baggage in Go context. This package exists because the OpenTracing bridge to
+OpenTelemetry needs to synchronize state whenever baggage for a context is
+modified and that context contains an OpenTracing span. If it were not for
+this need this package would not need to exist and the
+`go.opentelemetry.io/otel/baggage` package would be the singular place where
+W3C baggage is handled.
+*/
+package baggage // import "go.opentelemetry.io/otel/internal/baggage"
+
+// List is the collection of baggage members. The W3C allows for duplicates,
+// but OpenTelemetry does not, therefore, this is represented as a map.
+type List map[string]Item
+
+// Item is the value and metadata properties part of a list-member.
+type Item struct {
+	Value      string
+	Properties []Property
+}
+
+// Property is a metadata entry for a list-member.
+type Property struct {
+	Key, Value string
+
+	// HasValue indicates if a zero-value value means the property does not
+	// have a value or if it was the zero-value.
+	HasValue bool
+}

vendor/go.opentelemetry.io/otel/internal/baggage/context.go

@@ -0,0 +1,95 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package baggage // import "go.opentelemetry.io/otel/internal/baggage"
+
+import "context"
+
+type baggageContextKeyType int
+
+const baggageKey baggageContextKeyType = iota
+
+// SetHookFunc is a callback called when storing baggage in the context.
+type SetHookFunc func(context.Context, List) context.Context
+
+// GetHookFunc is a callback called when getting baggage from the context.
+type GetHookFunc func(context.Context, List) List
+
+type baggageState struct {
+	list List
+
+	setHook SetHookFunc
+	getHook GetHookFunc
+}
+
+// ContextWithSetHook returns a copy of parent with hook configured to be
+// invoked every time ContextWithBaggage is called.
+//
+// Passing nil SetHookFunc creates a context with no set hook to call.
+func ContextWithSetHook(parent context.Context, hook SetHookFunc) context.Context {
+	var s baggageState
+	switch v := parent.Value(baggageKey).(type) {
+	case baggageState:
+		s = v
+	}
+
+	s.setHook = hook
+	return context.WithValue(parent, baggageKey, s)
+}
+
+// ContextWithGetHook returns a copy of parent with hook configured to be
+// invoked every time FromContext is called.
+//
+// Passing nil GetHookFunc creates a context with no get hook to call.
+func ContextWithGetHook(parent context.Context, hook GetHookFunc) context.Context {
+	var s baggageState
+	switch v := parent.Value(baggageKey).(type) {
+	case baggageState:
+		s = v
+	}
+
+	s.getHook = hook
+	return context.WithValue(parent, baggageKey, s)
+}
+
+// ContextWithList returns a copy of parent with baggage. Passing nil list
+// returns a context without any baggage.
+func ContextWithList(parent context.Context, list List) context.Context {
+	var s baggageState
+	switch v := parent.Value(baggageKey).(type) {
+	case baggageState:
+		s = v
+	}
+
+	s.list = list
+	ctx := context.WithValue(parent, baggageKey, s)
+	if s.setHook != nil {
+		ctx = s.setHook(ctx, list)
+	}
+
+	return ctx
+}
+
+// ListFromContext returns the baggage contained in ctx.
+func ListFromContext(ctx context.Context) List {
+	switch v := ctx.Value(baggageKey).(type) {
+	case baggageState:
+		if v.getHook != nil {
+			return v.getHook(ctx, v.list)
+		}
+		return v.list
+	default:
+		return nil
+	}
+}

vendor/go.opentelemetry.io/otel/internal/global/internal_logging.go

@@ -0,0 +1,63 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package global // import "go.opentelemetry.io/otel/internal/global"
+
+import (
+	"log"
+	"os"
+	"sync"
+
+	"github.com/go-logr/logr"
+	"github.com/go-logr/stdr"
+)
+
+// globalLogger is the logging interface used within the otel api and sdk provide deatails of the internals.
+//
+// The default logger uses stdr which is backed by the standard `log.Logger`
+// interface. This logger will only show messages at the Error Level.
+var globalLogger logr.Logger = stdr.New(log.New(os.Stderr, "", log.LstdFlags|log.Lshortfile))
+var globalLoggerLock = &sync.RWMutex{}
+
+// SetLogger overrides the globalLogger with l.
+//
+// To see Info messages use a logger with `l.V(1).Enabled() == true`
+// To see Debug messages use a logger with `l.V(5).Enabled() == true`
+func SetLogger(l logr.Logger) {
+	globalLoggerLock.Lock()
+	defer globalLoggerLock.Unlock()
+	globalLogger = l
+}
+
+// Info prints messages about the general state of the API or SDK.
+// This should usually be less then 5 messages a minute
+func Info(msg string, keysAndValues ...interface{}) {
+	globalLoggerLock.RLock()
+	defer globalLoggerLock.RUnlock()
+	globalLogger.V(1).Info(msg, keysAndValues...)
+}
+
+// Error prints messages about exceptional states of the API or SDK.
+func Error(err error, msg string, keysAndValues ...interface{}) {
+	globalLoggerLock.RLock()
+	defer globalLoggerLock.RUnlock()
+	globalLogger.Error(err, msg, keysAndValues...)
+}
+
+// Debug prints messages about all internal changes in the API or SDK.
+func Debug(msg string, keysAndValues ...interface{}) {
+	globalLoggerLock.RLock()
+	defer globalLoggerLock.RUnlock()
+	globalLogger.V(5).Info(msg, keysAndValues...)
+}

vendor/go.opentelemetry.io/otel/internal/global/propagator.go

@@ -0,0 +1,82 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package global // import "go.opentelemetry.io/otel/internal/global"
+
+import (
+	"context"
+	"sync"
+
+	"go.opentelemetry.io/otel/propagation"
+)
+
+// textMapPropagator is a default TextMapPropagator that delegates calls to a
+// registered delegate if one is set, otherwise it defaults to delegating the
+// calls to a the default no-op propagation.TextMapPropagator.
+type textMapPropagator struct {
+	mtx      sync.Mutex
+	once     sync.Once
+	delegate propagation.TextMapPropagator
+	noop     propagation.TextMapPropagator
+}
+
+// Compile-time guarantee that textMapPropagator implements the
+// propagation.TextMapPropagator interface.
+var _ propagation.TextMapPropagator = (*textMapPropagator)(nil)
+
+func newTextMapPropagator() *textMapPropagator {
+	return &textMapPropagator{
+		noop: propagation.NewCompositeTextMapPropagator(),
+	}
+}
+
+// SetDelegate sets a delegate propagation.TextMapPropagator that all calls are
+// forwarded to. Delegation can only be performed once, all subsequent calls
+// perform no delegation.
+func (p *textMapPropagator) SetDelegate(delegate propagation.TextMapPropagator) {
+	if delegate == nil {
+		return
+	}
+
+	p.mtx.Lock()
+	p.once.Do(func() { p.delegate = delegate })
+	p.mtx.Unlock()
+}
+
+// effectiveDelegate returns the current delegate of p if one is set,
+// otherwise the default noop TextMapPropagator is returned. This method
+// can be called concurrently.
+func (p *textMapPropagator) effectiveDelegate() propagation.TextMapPropagator {
+	p.mtx.Lock()
+	defer p.mtx.Unlock()
+	if p.delegate != nil {
+		return p.delegate
+	}
+	return p.noop
+}
+
+// Inject set cross-cutting concerns from the Context into the carrier.
+func (p *textMapPropagator) Inject(ctx context.Context, carrier propagation.TextMapCarrier) {
+	p.effectiveDelegate().Inject(ctx, carrier)
+}
+
+// Extract reads cross-cutting concerns from the carrier into a Context.
+func (p *textMapPropagator) Extract(ctx context.Context, carrier propagation.TextMapCarrier) context.Context {
+	return p.effectiveDelegate().Extract(ctx, carrier)
+}
+
+// Fields returns the keys whose values are set with Inject.
+func (p *textMapPropagator) Fields() []string {
+	return p.effectiveDelegate().Fields()
+}

vendor/go.opentelemetry.io/otel/internal/global/state.go

@@ -0,0 +1,127 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package global // import "go.opentelemetry.io/otel/internal/global"
+
+import (
+	"errors"
+	"sync"
+	"sync/atomic"
+	"testing"
+
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type (
+	tracerProviderHolder struct {
+		tp trace.TracerProvider
+	}
+
+	propagatorsHolder struct {
+		tm propagation.TextMapPropagator
+	}
+)
+
+var (
+	globalTracer      = defaultTracerValue()
+	globalPropagators = defaultPropagatorsValue()
+
+	delegateTraceOnce             sync.Once
+	delegateTextMapPropagatorOnce sync.Once
+)
+
+// TracerProvider is the internal implementation for global.TracerProvider.
+func TracerProvider() trace.TracerProvider {
+	return globalTracer.Load().(tracerProviderHolder).tp
+}
+
+// SetTracerProvider is the internal implementation for global.SetTracerProvider.
+func SetTracerProvider(tp trace.TracerProvider) {
+	current := TracerProvider()
+
+	if _, cOk := current.(*tracerProvider); cOk {
+		if _, tpOk := tp.(*tracerProvider); tpOk && current == tp {
+			// Do not assign the default delegating TracerProvider to delegate
+			// to itself.
+			Error(
+				errors.New("no delegate configured in tracer provider"),
+				"Setting tracer provider to it's current value. No delegate will be configured",
+			)
+			return
+		}
+	}
+
+	delegateTraceOnce.Do(func() {
+		if def, ok := current.(*tracerProvider); ok {
+			def.setDelegate(tp)
+		}
+	})
+	globalTracer.Store(tracerProviderHolder{tp: tp})
+}
+
+// TextMapPropagator is the internal implementation for global.TextMapPropagator.
+func TextMapPropagator() propagation.TextMapPropagator {
+	return globalPropagators.Load().(propagatorsHolder).tm
+}
+
+// SetTextMapPropagator is the internal implementation for global.SetTextMapPropagator.
+func SetTextMapPropagator(p propagation.TextMapPropagator) {
+	current := TextMapPropagator()
+
+	if _, cOk := current.(*textMapPropagator); cOk {
+		if _, pOk := p.(*textMapPropagator); pOk && current == p {
+			// Do not assign the default delegating TextMapPropagator to
+			// delegate to itself.
+			Error(
+				errors.New("no delegate configured in text map propagator"),
+				"Setting text map propagator to it's current value. No delegate will be configured",
+			)
+			return
+		}
+	}
+
+	// For the textMapPropagator already returned by TextMapPropagator
+	// delegate to p.
+	delegateTextMapPropagatorOnce.Do(func() {
+		if def, ok := current.(*textMapPropagator); ok {
+			def.SetDelegate(p)
+		}
+	})
+	// Return p when subsequent calls to TextMapPropagator are made.
+	globalPropagators.Store(propagatorsHolder{tm: p})
+}
+
+func defaultTracerValue() *atomic.Value {
+	v := &atomic.Value{}
+	v.Store(tracerProviderHolder{tp: &tracerProvider{}})
+	return v
+}
+
+func defaultPropagatorsValue() *atomic.Value {
+	v := &atomic.Value{}
+	v.Store(propagatorsHolder{tm: newTextMapPropagator()})
+	return v
+}
+
+// ResetForTest configures the test to restores the initial global state during
+// its Cleanup step
+func ResetForTest(t testing.TB) {
+	t.Cleanup(func() {
+		globalTracer = defaultTracerValue()
+		globalPropagators = defaultPropagatorsValue()
+		delegateTraceOnce = sync.Once{}
+		delegateTextMapPropagatorOnce = sync.Once{}
+	})
+}

vendor/go.opentelemetry.io/otel/internal/global/trace.go

@@ -0,0 +1,192 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package global // import "go.opentelemetry.io/otel/internal/global"
+
+/*
+This file contains the forwarding implementation of the TracerProvider used as
+the default global instance. Prior to initialization of an SDK, Tracers
+returned by the global TracerProvider will provide no-op functionality. This
+means that all Span created prior to initialization are no-op Spans.
+
+Once an SDK has been initialized, all provided no-op Tracers are swapped for
+Tracers provided by the SDK defined TracerProvider. However, any Span started
+prior to this initialization does not change its behavior. Meaning, the Span
+remains a no-op Span.
+
+The implementation to track and swap Tracers locks all new Tracer creation
+until the swap is complete. This assumes that this operation is not
+performance-critical. If that assumption is incorrect, be sure to configure an
+SDK prior to any Tracer creation.
+*/
+
+import (
+	"context"
+	"sync"
+	"sync/atomic"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// tracerProvider is a placeholder for a configured SDK TracerProvider.
+//
+// All TracerProvider functionality is forwarded to a delegate once
+// configured.
+type tracerProvider struct {
+	mtx      sync.Mutex
+	tracers  map[il]*tracer
+	delegate trace.TracerProvider
+}
+
+// Compile-time guarantee that tracerProvider implements the TracerProvider
+// interface.
+var _ trace.TracerProvider = &tracerProvider{}
+
+// setDelegate configures p to delegate all TracerProvider functionality to
+// provider.
+//
+// All Tracers provided prior to this function call are switched out to be
+// Tracers provided by provider.
+//
+// It is guaranteed by the caller that this happens only once.
+func (p *tracerProvider) setDelegate(provider trace.TracerProvider) {
+	p.mtx.Lock()
+	defer p.mtx.Unlock()
+
+	p.delegate = provider
+
+	if len(p.tracers) == 0 {
+		return
+	}
+
+	for _, t := range p.tracers {
+		t.setDelegate(provider)
+	}
+
+	p.tracers = nil
+}
+
+// Tracer implements TracerProvider.
+func (p *tracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.Tracer {
+	p.mtx.Lock()
+	defer p.mtx.Unlock()
+
+	if p.delegate != nil {
+		return p.delegate.Tracer(name, opts...)
+	}
+
+	// At this moment it is guaranteed that no sdk is installed, save the tracer in the tracers map.
+
+	c := trace.NewTracerConfig(opts...)
+	key := il{
+		name:    name,
+		version: c.InstrumentationVersion(),
+	}
+
+	if p.tracers == nil {
+		p.tracers = make(map[il]*tracer)
+	}
+
+	if val, ok := p.tracers[key]; ok {
+		return val
+	}
+
+	t := &tracer{name: name, opts: opts, provider: p}
+	p.tracers[key] = t
+	return t
+}
+
+type il struct {
+	name    string
+	version string
+}
+
+// tracer is a placeholder for a trace.Tracer.
+//
+// All Tracer functionality is forwarded to a delegate once configured.
+// Otherwise, all functionality is forwarded to a NoopTracer.
+type tracer struct {
+	name     string
+	opts     []trace.TracerOption
+	provider *tracerProvider
+
+	delegate atomic.Value
+}
+
+// Compile-time guarantee that tracer implements the trace.Tracer interface.
+var _ trace.Tracer = &tracer{}
+
+// setDelegate configures t to delegate all Tracer functionality to Tracers
+// created by provider.
+//
+// All subsequent calls to the Tracer methods will be passed to the delegate.
+//
+// It is guaranteed by the caller that this happens only once.
+func (t *tracer) setDelegate(provider trace.TracerProvider) {
+	t.delegate.Store(provider.Tracer(t.name, t.opts...))
+}
+
+// Start implements trace.Tracer by forwarding the call to t.delegate if
+// set, otherwise it forwards the call to a NoopTracer.
+func (t *tracer) Start(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	delegate := t.delegate.Load()
+	if delegate != nil {
+		return delegate.(trace.Tracer).Start(ctx, name, opts...)
+	}
+
+	s := nonRecordingSpan{sc: trace.SpanContextFromContext(ctx), tracer: t}
+	ctx = trace.ContextWithSpan(ctx, s)
+	return ctx, s
+}
+
+// nonRecordingSpan is a minimal implementation of a Span that wraps a
+// SpanContext. It performs no operations other than to return the wrapped
+// SpanContext.
+type nonRecordingSpan struct {
+	sc     trace.SpanContext
+	tracer *tracer
+}
+
+var _ trace.Span = nonRecordingSpan{}
+
+// SpanContext returns the wrapped SpanContext.
+func (s nonRecordingSpan) SpanContext() trace.SpanContext { return s.sc }
+
+// IsRecording always returns false.
+func (nonRecordingSpan) IsRecording() bool { return false }
+
+// SetStatus does nothing.
+func (nonRecordingSpan) SetStatus(codes.Code, string) {}
+
+// SetError does nothing.
+func (nonRecordingSpan) SetError(bool) {}
+
+// SetAttributes does nothing.
+func (nonRecordingSpan) SetAttributes(...attribute.KeyValue) {}
+
+// End does nothing.
+func (nonRecordingSpan) End(...trace.SpanEndOption) {}
+
+// RecordError does nothing.
+func (nonRecordingSpan) RecordError(error, ...trace.EventOption) {}
+
+// AddEvent does nothing.
+func (nonRecordingSpan) AddEvent(string, ...trace.EventOption) {}
+
+// SetName does nothing.
+func (nonRecordingSpan) SetName(string) {}
+
+func (s nonRecordingSpan) TracerProvider() trace.TracerProvider { return s.tracer.provider }

vendor/go.opentelemetry.io/otel/internal/rawhelpers.go

@@ -0,0 +1,55 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal // import "go.opentelemetry.io/otel/internal"
+
+import (
+	"math"
+	"unsafe"
+)
+
+func BoolToRaw(b bool) uint64 {
+	if b {
+		return 1
+	}
+	return 0
+}
+
+func RawToBool(r uint64) bool {
+	return r != 0
+}
+
+func Int64ToRaw(i int64) uint64 {
+	return uint64(i)
+}
+
+func RawToInt64(r uint64) int64 {
+	return int64(r)
+}
+
+func Float64ToRaw(f float64) uint64 {
+	return math.Float64bits(f)
+}
+
+func RawToFloat64(r uint64) float64 {
+	return math.Float64frombits(r)
+}
+
+func RawPtrToFloat64Ptr(r *uint64) *float64 {
+	return (*float64)(unsafe.Pointer(r))
+}
+
+func RawPtrToInt64Ptr(r *uint64) *int64 {
+	return (*int64)(unsafe.Pointer(r))
+}

vendor/go.opentelemetry.io/otel/internal_logging.go

@@ -0,0 +1,26 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otel // import "go.opentelemetry.io/otel"
+
+import (
+	"github.com/go-logr/logr"
+
+	"go.opentelemetry.io/otel/internal/global"
+)
+
+// SetLogger configures the logger used internally to opentelemetry.
+func SetLogger(logger logr.Logger) {
+	global.SetLogger(logger)
+}

vendor/go.opentelemetry.io/otel/propagation.go

@@ -0,0 +1,31 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otel // import "go.opentelemetry.io/otel"
+
+import (
+	"go.opentelemetry.io/otel/internal/global"
+	"go.opentelemetry.io/otel/propagation"
+)
+
+// GetTextMapPropagator returns the global TextMapPropagator. If none has been
+// set, a No-Op TextMapPropagator is returned.
+func GetTextMapPropagator() propagation.TextMapPropagator {
+	return global.TextMapPropagator()
+}
+
+// SetTextMapPropagator sets propagator as the global TextMapPropagator.
+func SetTextMapPropagator(propagator propagation.TextMapPropagator) {
+	global.SetTextMapPropagator(propagator)
+}

vendor/go.opentelemetry.io/otel/propagation/baggage.go

@@ -0,0 +1,58 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package propagation // import "go.opentelemetry.io/otel/propagation"
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/baggage"
+)
+
+const baggageHeader = "baggage"
+
+// Baggage is a propagator that supports the W3C Baggage format.
+//
+// This propagates user-defined baggage associated with a trace. The complete
+// specification is defined at https://www.w3.org/TR/baggage/.
+type Baggage struct{}
+
+var _ TextMapPropagator = Baggage{}
+
+// Inject sets baggage key-values from ctx into the carrier.
+func (b Baggage) Inject(ctx context.Context, carrier TextMapCarrier) {
+	bStr := baggage.FromContext(ctx).String()
+	if bStr != "" {
+		carrier.Set(baggageHeader, bStr)
+	}
+}
+
+// Extract returns a copy of parent with the baggage from the carrier added.
+func (b Baggage) Extract(parent context.Context, carrier TextMapCarrier) context.Context {
+	bStr := carrier.Get(baggageHeader)
+	if bStr == "" {
+		return parent
+	}
+
+	bag, err := baggage.Parse(bStr)
+	if err != nil {
+		return parent
+	}
+	return baggage.ContextWithBaggage(parent, bag)
+}
+
+// Fields returns the keys who's values are set with Inject.
+func (b Baggage) Fields() []string {
+	return []string{baggageHeader}
+}

vendor/go.opentelemetry.io/otel/propagation/doc.go

@@ -0,0 +1,24 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package propagation contains OpenTelemetry context propagators.
+
+OpenTelemetry propagators are used to extract and inject context data from and
+into messages exchanged by applications. The propagator supported by this
+package is the W3C Trace Context encoding
+(https://www.w3.org/TR/trace-context/), and W3C Baggage
+(https://www.w3.org/TR/baggage/).
+*/
+package propagation // import "go.opentelemetry.io/otel/propagation"

vendor/go.opentelemetry.io/otel/propagation/propagation.go

@@ -0,0 +1,153 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package propagation // import "go.opentelemetry.io/otel/propagation"
+
+import (
+	"context"
+	"net/http"
+)
+
+// TextMapCarrier is the storage medium used by a TextMapPropagator.
+type TextMapCarrier interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Get returns the value associated with the passed key.
+	Get(key string) string
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Set stores the key-value pair.
+	Set(key string, value string)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Keys lists the keys stored in this carrier.
+	Keys() []string
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+// MapCarrier is a TextMapCarrier that uses a map held in memory as a storage
+// medium for propagated key-value pairs.
+type MapCarrier map[string]string
+
+// Compile time check that MapCarrier implements the TextMapCarrier.
+var _ TextMapCarrier = MapCarrier{}
+
+// Get returns the value associated with the passed key.
+func (c MapCarrier) Get(key string) string {
+	return c[key]
+}
+
+// Set stores the key-value pair.
+func (c MapCarrier) Set(key, value string) {
+	c[key] = value
+}
+
+// Keys lists the keys stored in this carrier.
+func (c MapCarrier) Keys() []string {
+	keys := make([]string, 0, len(c))
+	for k := range c {
+		keys = append(keys, k)
+	}
+	return keys
+}
+
+// HeaderCarrier adapts http.Header to satisfy the TextMapCarrier interface.
+type HeaderCarrier http.Header
+
+// Get returns the value associated with the passed key.
+func (hc HeaderCarrier) Get(key string) string {
+	return http.Header(hc).Get(key)
+}
+
+// Set stores the key-value pair.
+func (hc HeaderCarrier) Set(key string, value string) {
+	http.Header(hc).Set(key, value)
+}
+
+// Keys lists the keys stored in this carrier.
+func (hc HeaderCarrier) Keys() []string {
+	keys := make([]string, 0, len(hc))
+	for k := range hc {
+		keys = append(keys, k)
+	}
+	return keys
+}
+
+// TextMapPropagator propagates cross-cutting concerns as key-value text
+// pairs within a carrier that travels in-band across process boundaries.
+type TextMapPropagator interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Inject set cross-cutting concerns from the Context into the carrier.
+	Inject(ctx context.Context, carrier TextMapCarrier)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Extract reads cross-cutting concerns from the carrier into a Context.
+	Extract(ctx context.Context, carrier TextMapCarrier) context.Context
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Fields returns the keys whose values are set with Inject.
+	Fields() []string
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+type compositeTextMapPropagator []TextMapPropagator
+
+func (p compositeTextMapPropagator) Inject(ctx context.Context, carrier TextMapCarrier) {
+	for _, i := range p {
+		i.Inject(ctx, carrier)
+	}
+}
+
+func (p compositeTextMapPropagator) Extract(ctx context.Context, carrier TextMapCarrier) context.Context {
+	for _, i := range p {
+		ctx = i.Extract(ctx, carrier)
+	}
+	return ctx
+}
+
+func (p compositeTextMapPropagator) Fields() []string {
+	unique := make(map[string]struct{})
+	for _, i := range p {
+		for _, k := range i.Fields() {
+			unique[k] = struct{}{}
+		}
+	}
+
+	fields := make([]string, 0, len(unique))
+	for k := range unique {
+		fields = append(fields, k)
+	}
+	return fields
+}
+
+// NewCompositeTextMapPropagator returns a unified TextMapPropagator from the
+// group of passed TextMapPropagator. This allows different cross-cutting
+// concerns to be propagates in a unified manner.
+//
+// The returned TextMapPropagator will inject and extract cross-cutting
+// concerns in the order the TextMapPropagators were provided. Additionally,
+// the Fields method will return a de-duplicated slice of the keys that are
+// set with the Inject method.
+func NewCompositeTextMapPropagator(p ...TextMapPropagator) TextMapPropagator {
+	return compositeTextMapPropagator(p)
+}

vendor/go.opentelemetry.io/otel/propagation/trace_context.go

@@ -0,0 +1,159 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package propagation // import "go.opentelemetry.io/otel/propagation"
+
+import (
+	"context"
+	"encoding/hex"
+	"fmt"
+	"regexp"
+
+	"go.opentelemetry.io/otel/trace"
+)
+
+const (
+	supportedVersion  = 0
+	maxVersion        = 254
+	traceparentHeader = "traceparent"
+	tracestateHeader  = "tracestate"
+)
+
+// TraceContext is a propagator that supports the W3C Trace Context format
+// (https://www.w3.org/TR/trace-context/)
+//
+// This propagator will propagate the traceparent and tracestate headers to
+// guarantee traces are not broken. It is up to the users of this propagator
+// to choose if they want to participate in a trace by modifying the
+// traceparent header and relevant parts of the tracestate header containing
+// their proprietary information.
+type TraceContext struct{}
+
+var _ TextMapPropagator = TraceContext{}
+var traceCtxRegExp = regexp.MustCompile("^(?P<version>[0-9a-f]{2})-(?P<traceID>[a-f0-9]{32})-(?P<spanID>[a-f0-9]{16})-(?P<traceFlags>[a-f0-9]{2})(?:-.*)?$")
+
+// Inject set tracecontext from the Context into the carrier.
+func (tc TraceContext) Inject(ctx context.Context, carrier TextMapCarrier) {
+	sc := trace.SpanContextFromContext(ctx)
+	if !sc.IsValid() {
+		return
+	}
+
+	if ts := sc.TraceState().String(); ts != "" {
+		carrier.Set(tracestateHeader, ts)
+	}
+
+	// Clear all flags other than the trace-context supported sampling bit.
+	flags := sc.TraceFlags() & trace.FlagsSampled
+
+	h := fmt.Sprintf("%.2x-%s-%s-%s",
+		supportedVersion,
+		sc.TraceID(),
+		sc.SpanID(),
+		flags)
+	carrier.Set(traceparentHeader, h)
+}
+
+// Extract reads tracecontext from the carrier into a returned Context.
+//
+// The returned Context will be a copy of ctx and contain the extracted
+// tracecontext as the remote SpanContext. If the extracted tracecontext is
+// invalid, the passed ctx will be returned directly instead.
+func (tc TraceContext) Extract(ctx context.Context, carrier TextMapCarrier) context.Context {
+	sc := tc.extract(carrier)
+	if !sc.IsValid() {
+		return ctx
+	}
+	return trace.ContextWithRemoteSpanContext(ctx, sc)
+}
+
+func (tc TraceContext) extract(carrier TextMapCarrier) trace.SpanContext {
+	h := carrier.Get(traceparentHeader)
+	if h == "" {
+		return trace.SpanContext{}
+	}
+
+	matches := traceCtxRegExp.FindStringSubmatch(h)
+
+	if len(matches) == 0 {
+		return trace.SpanContext{}
+	}
+
+	if len(matches) < 5 { // four subgroups plus the overall match
+		return trace.SpanContext{}
+	}
+
+	if len(matches[1]) != 2 {
+		return trace.SpanContext{}
+	}
+	ver, err := hex.DecodeString(matches[1])
+	if err != nil {
+		return trace.SpanContext{}
+	}
+	version := int(ver[0])
+	if version > maxVersion {
+		return trace.SpanContext{}
+	}
+
+	if version == 0 && len(matches) != 5 { // four subgroups plus the overall match
+		return trace.SpanContext{}
+	}
+
+	if len(matches[2]) != 32 {
+		return trace.SpanContext{}
+	}
+
+	var scc trace.SpanContextConfig
+
+	scc.TraceID, err = trace.TraceIDFromHex(matches[2][:32])
+	if err != nil {
+		return trace.SpanContext{}
+	}
+
+	if len(matches[3]) != 16 {
+		return trace.SpanContext{}
+	}
+	scc.SpanID, err = trace.SpanIDFromHex(matches[3])
+	if err != nil {
+		return trace.SpanContext{}
+	}
+
+	if len(matches[4]) != 2 {
+		return trace.SpanContext{}
+	}
+	opts, err := hex.DecodeString(matches[4])
+	if err != nil || len(opts) < 1 || (version == 0 && opts[0] > 2) {
+		return trace.SpanContext{}
+	}
+	// Clear all flags other than the trace-context supported sampling bit.
+	scc.TraceFlags = trace.TraceFlags(opts[0]) & trace.FlagsSampled
+
+	// Ignore the error returned here. Failure to parse tracestate MUST NOT
+	// affect the parsing of traceparent according to the W3C tracecontext
+	// specification.
+	scc.TraceState, _ = trace.ParseTraceState(carrier.Get(tracestateHeader))
+	scc.Remote = true
+
+	sc := trace.NewSpanContext(scc)
+	if !sc.IsValid() {
+		return trace.SpanContext{}
+	}
+
+	return sc
+}
+
+// Fields returns the keys who's values are set with Inject.
+func (tc TraceContext) Fields() []string {
+	return []string{traceparentHeader, tracestateHeader}
+}

vendor/go.opentelemetry.io/otel/sdk/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
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+      other entities that control, are controlled by, or are under common
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+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
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+      including but not limited to software source code, documentation
+      source, and configuration files.
+
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+      transformation or translation of a Source form, including but
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+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
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+      form, that is based on (or derived from) the Work and for which the
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+      "Contribution" shall mean any work of authorship, including
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+      to the Licensor or its representatives, including but not limited to
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+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
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+      subsequently incorporated within the Work.
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+      copyright license to reproduce, prepare Derivative Works of,
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+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
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+      negligent acts) or agreed to in writing, shall any Contributor be
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+
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+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
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+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
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+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/go.opentelemetry.io/otel/sdk/instrumentation/library.go

@@ -0,0 +1,33 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package instrumentation provides an instrumentation library structure to be
+passed to both the OpenTelemetry Tracer and Meter components.
+
+For more information see
+[this](https://github.com/open-telemetry/oteps/blob/main/text/0083-component.md).
+*/
+package instrumentation // import "go.opentelemetry.io/otel/sdk/instrumentation"
+
+// Library represents the instrumentation library.
+type Library struct {
+	// Name is the name of the instrumentation library. This should be the
+	// Go package name of that library.
+	Name string
+	// Version is the version of the instrumentation library.
+	Version string
+	// SchemaURL of the telemetry emitted by the library.
+	SchemaURL string
+}

vendor/go.opentelemetry.io/otel/sdk/internal/env/env.go

@@ -0,0 +1,186 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package env // import "go.opentelemetry.io/otel/sdk/internal/env"
+
+import (
+	"os"
+	"strconv"
+
+	"go.opentelemetry.io/otel/internal/global"
+)
+
+// Environment variable names
+const (
+	// BatchSpanProcessorScheduleDelayKey
+	// Delay interval between two consecutive exports.
+	// i.e. 5000
+	BatchSpanProcessorScheduleDelayKey = "OTEL_BSP_SCHEDULE_DELAY"
+	// BatchSpanProcessorExportTimeoutKey
+	// Maximum allowed time to export data.
+	// i.e. 3000
+	BatchSpanProcessorExportTimeoutKey = "OTEL_BSP_EXPORT_TIMEOUT"
+	// BatchSpanProcessorMaxQueueSizeKey
+	// Maximum queue size
+	// i.e. 2048
+	BatchSpanProcessorMaxQueueSizeKey = "OTEL_BSP_MAX_QUEUE_SIZE"
+	// BatchSpanProcessorMaxExportBatchSizeKey
+	// Maximum batch size
+	// Note: Must be less than or equal to EnvBatchSpanProcessorMaxQueueSize
+	// i.e. 512
+	BatchSpanProcessorMaxExportBatchSizeKey = "OTEL_BSP_MAX_EXPORT_BATCH_SIZE"
+
+	// AttributeValueLengthKey
+	// Maximum allowed attribute value size.
+	AttributeValueLengthKey = "OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT"
+
+	// AttributeCountKey
+	// Maximum allowed span attribute count
+	AttributeCountKey = "OTEL_ATTRIBUTE_COUNT_LIMIT"
+
+	// SpanAttributeValueLengthKey
+	// Maximum allowed attribute value size for a span.
+	SpanAttributeValueLengthKey = "OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT"
+
+	// SpanAttributeCountKey
+	// Maximum allowed span attribute count for a span.
+	SpanAttributeCountKey = "OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT"
+
+	// SpanEventCountKey
+	// Maximum allowed span event count.
+	SpanEventCountKey = "OTEL_SPAN_EVENT_COUNT_LIMIT"
+
+	// SpanEventAttributeCountKey
+	// Maximum allowed attribute per span event count.
+	SpanEventAttributeCountKey = "OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT"
+
+	// SpanLinkCountKey
+	// Maximum allowed span link count.
+	SpanLinkCountKey = "OTEL_SPAN_LINK_COUNT_LIMIT"
+
+	// SpanLinkAttributeCountKey
+	// Maximum allowed attribute per span link count.
+	SpanLinkAttributeCountKey = "OTEL_LINK_ATTRIBUTE_COUNT_LIMIT"
+)
+
+// firstInt returns the value of the first matching environment variable from
+// keys. If the value is not an integer or no match is found, defaultValue is
+// returned.
+func firstInt(defaultValue int, keys ...string) int {
+	for _, key := range keys {
+		value, ok := os.LookupEnv(key)
+		if !ok {
+			continue
+		}
+
+		intValue, err := strconv.Atoi(value)
+		if err != nil {
+			global.Info("Got invalid value, number value expected.", key, value)
+			return defaultValue
+		}
+
+		return intValue
+	}
+
+	return defaultValue
+}
+
+// IntEnvOr returns the int value of the environment variable with name key if
+// it exists and the value is an int. Otherwise, defaultValue is returned.
+func IntEnvOr(key string, defaultValue int) int {
+	value, ok := os.LookupEnv(key)
+	if !ok {
+		return defaultValue
+	}
+
+	intValue, err := strconv.Atoi(value)
+	if err != nil {
+		global.Info("Got invalid value, number value expected.", key, value)
+		return defaultValue
+	}
+
+	return intValue
+}
+
+// BatchSpanProcessorScheduleDelay returns the environment variable value for
+// the OTEL_BSP_SCHEDULE_DELAY key if it exists, otherwise defaultValue is
+// returned.
+func BatchSpanProcessorScheduleDelay(defaultValue int) int {
+	return IntEnvOr(BatchSpanProcessorScheduleDelayKey, defaultValue)
+}
+
+// BatchSpanProcessorExportTimeout returns the environment variable value for
+// the OTEL_BSP_EXPORT_TIMEOUT key if it exists, otherwise defaultValue is
+// returned.
+func BatchSpanProcessorExportTimeout(defaultValue int) int {
+	return IntEnvOr(BatchSpanProcessorExportTimeoutKey, defaultValue)
+}
+
+// BatchSpanProcessorMaxQueueSize returns the environment variable value for
+// the OTEL_BSP_MAX_QUEUE_SIZE key if it exists, otherwise defaultValue is
+// returned.
+func BatchSpanProcessorMaxQueueSize(defaultValue int) int {
+	return IntEnvOr(BatchSpanProcessorMaxQueueSizeKey, defaultValue)
+}
+
+// BatchSpanProcessorMaxExportBatchSize returns the environment variable value for
+// the OTEL_BSP_MAX_EXPORT_BATCH_SIZE key if it exists, otherwise defaultValue
+// is returned.
+func BatchSpanProcessorMaxExportBatchSize(defaultValue int) int {
+	return IntEnvOr(BatchSpanProcessorMaxExportBatchSizeKey, defaultValue)
+}
+
+// SpanAttributeValueLength returns the environment variable value for the
+// OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT key if it exists. Otherwise, the
+// environment variable value for OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT is
+// returned or defaultValue if that is not set.
+func SpanAttributeValueLength(defaultValue int) int {
+	return firstInt(defaultValue, SpanAttributeValueLengthKey, AttributeValueLengthKey)
+}
+
+// SpanAttributeCount returns the environment variable value for the
+// OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT key if it exists. Otherwise, the
+// environment variable value for OTEL_ATTRIBUTE_COUNT_LIMIT is returned or
+// defaultValue if that is not set.
+func SpanAttributeCount(defaultValue int) int {
+	return firstInt(defaultValue, SpanAttributeCountKey, AttributeCountKey)
+}
+
+// SpanEventCount returns the environment variable value for the
+// OTEL_SPAN_EVENT_COUNT_LIMIT key if it exists, otherwise defaultValue is
+// returned.
+func SpanEventCount(defaultValue int) int {
+	return IntEnvOr(SpanEventCountKey, defaultValue)
+}
+
+// SpanEventAttributeCount returns the environment variable value for the
+// OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT key if it exists, otherwise defaultValue
+// is returned.
+func SpanEventAttributeCount(defaultValue int) int {
+	return IntEnvOr(SpanEventAttributeCountKey, defaultValue)
+}
+
+// SpanLinkCount returns the environment variable value for the
+// OTEL_SPAN_LINK_COUNT_LIMIT key if it exists, otherwise defaultValue is
+// returned.
+func SpanLinkCount(defaultValue int) int {
+	return IntEnvOr(SpanLinkCountKey, defaultValue)
+}
+
+// SpanLinkAttributeCount returns the environment variable value for the
+// OTEL_LINK_ATTRIBUTE_COUNT_LIMIT key if it exists, otherwise defaultValue is
+// returned.
+func SpanLinkAttributeCount(defaultValue int) int {
+	return IntEnvOr(SpanLinkAttributeCountKey, defaultValue)
+}

vendor/go.opentelemetry.io/otel/sdk/internal/internal.go

@@ -0,0 +1,37 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal // import "go.opentelemetry.io/otel/sdk/internal"
+
+import (
+	"fmt"
+	"time"
+
+	"go.opentelemetry.io/otel"
+)
+
+// UserAgent is the user agent to be added to the outgoing
+// requests from the exporters.
+var UserAgent = fmt.Sprintf("opentelemetry-go/%s", otel.Version())
+
+// MonotonicEndTime returns the end time at present
+// but offset from start, monotonically.
+//
+// The monotonic clock is used in subtractions hence
+// the duration since start added back to start gives
+// end as a monotonic time.
+// See https://golang.org/pkg/time/#hdr-Monotonic_Clocks
+func MonotonicEndTime(start time.Time) time.Time {
+	return start.Add(time.Since(start))
+}

vendor/go.opentelemetry.io/otel/sdk/resource/auto.go

@@ -0,0 +1,72 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+	"errors"
+	"fmt"
+)
+
+var (
+	// ErrPartialResource is returned by a detector when complete source
+	// information for a Resource is unavailable or the source information
+	// contains invalid values that are omitted from the returned Resource.
+	ErrPartialResource = errors.New("partial resource")
+)
+
+// Detector detects OpenTelemetry resource information
+type Detector interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Detect returns an initialized Resource based on gathered information.
+	// If the source information to construct a Resource contains invalid
+	// values, a Resource is returned with the valid parts of the source
+	// information used for initialization along with an appropriately
+	// wrapped ErrPartialResource error.
+	Detect(ctx context.Context) (*Resource, error)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+// Detect calls all input detectors sequentially and merges each result with the previous one.
+// It returns the merged error too.
+func Detect(ctx context.Context, detectors ...Detector) (*Resource, error) {
+	var autoDetectedRes *Resource
+	var errInfo []string
+	for _, detector := range detectors {
+		if detector == nil {
+			continue
+		}
+		res, err := detector.Detect(ctx)
+		if err != nil {
+			errInfo = append(errInfo, err.Error())
+			if !errors.Is(err, ErrPartialResource) {
+				continue
+			}
+		}
+		autoDetectedRes, err = Merge(autoDetectedRes, res)
+		if err != nil {
+			errInfo = append(errInfo, err.Error())
+		}
+	}
+
+	var aggregatedError error
+	if len(errInfo) > 0 {
+		aggregatedError = fmt.Errorf("detecting resources: %s", errInfo)
+	}
+	return autoDetectedRes, aggregatedError
+}

vendor/go.opentelemetry.io/otel/sdk/resource/builtin.go

@@ -0,0 +1,108 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+)
+
+type (
+	// telemetrySDK is a Detector that provides information about
+	// the OpenTelemetry SDK used.  This Detector is included as a
+	// builtin. If these resource attributes are not wanted, use
+	// the WithTelemetrySDK(nil) or WithoutBuiltin() options to
+	// explicitly disable them.
+	telemetrySDK struct{}
+
+	// host is a Detector that provides information about the host
+	// being run on. This Detector is included as a builtin. If
+	// these resource attributes are not wanted, use the
+	// WithHost(nil) or WithoutBuiltin() options to explicitly
+	// disable them.
+	host struct{}
+
+	stringDetector struct {
+		schemaURL string
+		K         attribute.Key
+		F         func() (string, error)
+	}
+
+	defaultServiceNameDetector struct{}
+)
+
+var (
+	_ Detector = telemetrySDK{}
+	_ Detector = host{}
+	_ Detector = stringDetector{}
+	_ Detector = defaultServiceNameDetector{}
+)
+
+// Detect returns a *Resource that describes the OpenTelemetry SDK used.
+func (telemetrySDK) Detect(context.Context) (*Resource, error) {
+	return NewWithAttributes(
+		semconv.SchemaURL,
+		semconv.TelemetrySDKNameKey.String("opentelemetry"),
+		semconv.TelemetrySDKLanguageKey.String("go"),
+		semconv.TelemetrySDKVersionKey.String(otel.Version()),
+	), nil
+}
+
+// Detect returns a *Resource that describes the host being run on.
+func (host) Detect(ctx context.Context) (*Resource, error) {
+	return StringDetector(semconv.SchemaURL, semconv.HostNameKey, os.Hostname).Detect(ctx)
+}
+
+// StringDetector returns a Detector that will produce a *Resource
+// containing the string as a value corresponding to k. The resulting Resource
+// will have the specified schemaURL.
+func StringDetector(schemaURL string, k attribute.Key, f func() (string, error)) Detector {
+	return stringDetector{schemaURL: schemaURL, K: k, F: f}
+}
+
+// Detect returns a *Resource that describes the string as a value
+// corresponding to attribute.Key as well as the specific schemaURL.
+func (sd stringDetector) Detect(ctx context.Context) (*Resource, error) {
+	value, err := sd.F()
+	if err != nil {
+		return nil, fmt.Errorf("%s: %w", string(sd.K), err)
+	}
+	a := sd.K.String(value)
+	if !a.Valid() {
+		return nil, fmt.Errorf("invalid attribute: %q -> %q", a.Key, a.Value.Emit())
+	}
+	return NewWithAttributes(sd.schemaURL, sd.K.String(value)), nil
+}
+
+// Detect implements Detector
+func (defaultServiceNameDetector) Detect(ctx context.Context) (*Resource, error) {
+	return StringDetector(
+		semconv.SchemaURL,
+		semconv.ServiceNameKey,
+		func() (string, error) {
+			executable, err := os.Executable()
+			if err != nil {
+				return "unknown_service:go", nil
+			}
+			return "unknown_service:" + filepath.Base(executable), nil
+		},
+	).Detect(ctx)
+}

vendor/go.opentelemetry.io/otel/sdk/resource/config.go

@@ -0,0 +1,199 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/attribute"
+)
+
+// config contains configuration for Resource creation.
+type config struct {
+	// detectors that will be evaluated.
+	detectors []Detector
+	// SchemaURL to associate with the Resource.
+	schemaURL string
+}
+
+// Option is the interface that applies a configuration option.
+type Option interface {
+	// apply sets the Option value of a config.
+	apply(config) config
+}
+
+// WithAttributes adds attributes to the configured Resource.
+func WithAttributes(attributes ...attribute.KeyValue) Option {
+	return WithDetectors(detectAttributes{attributes})
+}
+
+type detectAttributes struct {
+	attributes []attribute.KeyValue
+}
+
+func (d detectAttributes) Detect(context.Context) (*Resource, error) {
+	return NewSchemaless(d.attributes...), nil
+}
+
+// WithDetectors adds detectors to be evaluated for the configured resource.
+func WithDetectors(detectors ...Detector) Option {
+	return detectorsOption{detectors: detectors}
+}
+
+type detectorsOption struct {
+	detectors []Detector
+}
+
+func (o detectorsOption) apply(cfg config) config {
+	cfg.detectors = append(cfg.detectors, o.detectors...)
+	return cfg
+}
+
+// WithFromEnv adds attributes from environment variables to the configured resource.
+func WithFromEnv() Option {
+	return WithDetectors(fromEnv{})
+}
+
+// WithHost adds attributes from the host to the configured resource.
+func WithHost() Option {
+	return WithDetectors(host{})
+}
+
+// WithTelemetrySDK adds TelemetrySDK version info to the configured resource.
+func WithTelemetrySDK() Option {
+	return WithDetectors(telemetrySDK{})
+}
+
+// WithSchemaURL sets the schema URL for the configured resource.
+func WithSchemaURL(schemaURL string) Option {
+	return schemaURLOption(schemaURL)
+}
+
+type schemaURLOption string
+
+func (o schemaURLOption) apply(cfg config) config {
+	cfg.schemaURL = string(o)
+	return cfg
+}
+
+// WithOS adds all the OS attributes to the configured Resource.
+// See individual WithOS* functions to configure specific attributes.
+func WithOS() Option {
+	return WithDetectors(
+		osTypeDetector{},
+		osDescriptionDetector{},
+	)
+}
+
+// WithOSType adds an attribute with the operating system type to the configured Resource.
+func WithOSType() Option {
+	return WithDetectors(osTypeDetector{})
+}
+
+// WithOSDescription adds an attribute with the operating system description to the
+// configured Resource. The formatted string is equivalent to the output of the
+// `uname -snrvm` command.
+func WithOSDescription() Option {
+	return WithDetectors(osDescriptionDetector{})
+}
+
+// WithProcess adds all the Process attributes to the configured Resource.
+//
+// Warning! This option will include process command line arguments. If these
+// contain sensitive information it will be included in the exported resource.
+//
+// This option is equivalent to calling WithProcessPID,
+// WithProcessExecutableName, WithProcessExecutablePath,
+// WithProcessCommandArgs, WithProcessOwner, WithProcessRuntimeName,
+// WithProcessRuntimeVersion, and WithProcessRuntimeDescription. See each
+// option function for information about what resource attributes each
+// includes.
+func WithProcess() Option {
+	return WithDetectors(
+		processPIDDetector{},
+		processExecutableNameDetector{},
+		processExecutablePathDetector{},
+		processCommandArgsDetector{},
+		processOwnerDetector{},
+		processRuntimeNameDetector{},
+		processRuntimeVersionDetector{},
+		processRuntimeDescriptionDetector{},
+	)
+}
+
+// WithProcessPID adds an attribute with the process identifier (PID) to the
+// configured Resource.
+func WithProcessPID() Option {
+	return WithDetectors(processPIDDetector{})
+}
+
+// WithProcessExecutableName adds an attribute with the name of the process
+// executable to the configured Resource.
+func WithProcessExecutableName() Option {
+	return WithDetectors(processExecutableNameDetector{})
+}
+
+// WithProcessExecutablePath adds an attribute with the full path to the process
+// executable to the configured Resource.
+func WithProcessExecutablePath() Option {
+	return WithDetectors(processExecutablePathDetector{})
+}
+
+// WithProcessCommandArgs adds an attribute with all the command arguments (including
+// the command/executable itself) as received by the process to the configured
+// Resource.
+//
+// Warning! This option will include process command line arguments. If these
+// contain sensitive information it will be included in the exported resource.
+func WithProcessCommandArgs() Option {
+	return WithDetectors(processCommandArgsDetector{})
+}
+
+// WithProcessOwner adds an attribute with the username of the user that owns the process
+// to the configured Resource.
+func WithProcessOwner() Option {
+	return WithDetectors(processOwnerDetector{})
+}
+
+// WithProcessRuntimeName adds an attribute with the name of the runtime of this
+// process to the configured Resource.
+func WithProcessRuntimeName() Option {
+	return WithDetectors(processRuntimeNameDetector{})
+}
+
+// WithProcessRuntimeVersion adds an attribute with the version of the runtime of
+// this process to the configured Resource.
+func WithProcessRuntimeVersion() Option {
+	return WithDetectors(processRuntimeVersionDetector{})
+}
+
+// WithProcessRuntimeDescription adds an attribute with an additional description
+// about the runtime of the process to the configured Resource.
+func WithProcessRuntimeDescription() Option {
+	return WithDetectors(processRuntimeDescriptionDetector{})
+}
+
+// WithContainer adds all the Container attributes to the configured Resource.
+// See individual WithContainer* functions to configure specific attributes.
+func WithContainer() Option {
+	return WithDetectors(
+		cgroupContainerIDDetector{},
+	)
+}
+
+// WithContainerID adds an attribute with the id of the container to the configured Resource.
+func WithContainerID() Option {
+	return WithDetectors(cgroupContainerIDDetector{})
+}

vendor/go.opentelemetry.io/otel/sdk/resource/container.go

@@ -0,0 +1,100 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"bufio"
+	"context"
+	"errors"
+	"io"
+	"os"
+	"regexp"
+
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+)
+
+type containerIDProvider func() (string, error)
+
+var (
+	containerID         containerIDProvider = getContainerIDFromCGroup
+	cgroupContainerIDRe                     = regexp.MustCompile(`^.*/(?:.*-)?([0-9a-f]+)(?:\.|\s*$)`)
+)
+
+type cgroupContainerIDDetector struct{}
+
+const cgroupPath = "/proc/self/cgroup"
+
+// Detect returns a *Resource that describes the id of the container.
+// If no container id found, an empty resource will be returned.
+func (cgroupContainerIDDetector) Detect(ctx context.Context) (*Resource, error) {
+	containerID, err := containerID()
+	if err != nil {
+		return nil, err
+	}
+
+	if containerID == "" {
+		return Empty(), nil
+	}
+	return NewWithAttributes(semconv.SchemaURL, semconv.ContainerIDKey.String(containerID)), nil
+}
+
+var (
+	defaultOSStat = os.Stat
+	osStat        = defaultOSStat
+
+	defaultOSOpen = func(name string) (io.ReadCloser, error) {
+		return os.Open(name)
+	}
+	osOpen = defaultOSOpen
+)
+
+// getContainerIDFromCGroup returns the id of the container from the cgroup file.
+// If no container id found, an empty string will be returned.
+func getContainerIDFromCGroup() (string, error) {
+	if _, err := osStat(cgroupPath); errors.Is(err, os.ErrNotExist) {
+		// File does not exist, skip
+		return "", nil
+	}
+
+	file, err := osOpen(cgroupPath)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	return getContainerIDFromReader(file), nil
+}
+
+// getContainerIDFromReader returns the id of the container from reader.
+func getContainerIDFromReader(reader io.Reader) string {
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		if id := getContainerIDFromLine(line); id != "" {
+			return id
+		}
+	}
+	return ""
+}
+
+// getContainerIDFromLine returns the id of the container from one string line.
+func getContainerIDFromLine(line string) string {
+	matches := cgroupContainerIDRe.FindStringSubmatch(line)
+	if len(matches) <= 1 {
+		return ""
+	}
+	return matches[1]
+}

vendor/go.opentelemetry.io/otel/sdk/resource/doc.go

@@ -0,0 +1,28 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package resource provides detecting and representing resources.
+//
+// The fundamental struct is a Resource which holds identifying information
+// about the entities for which telemetry is exported.
+//
+// To automatically construct Resources from an environment a Detector
+// interface is defined. Implementations of this interface can be passed to
+// the Detect function to generate a Resource from the merged information.
+//
+// To load a user defined Resource from the environment variable
+// OTEL_RESOURCE_ATTRIBUTES the FromEnv Detector can be used. It will interpret
+// the value as a list of comma delimited key/value pairs
+// (e.g. `<key1>=<value1>,<key2>=<value2>,...`).
+package resource // import "go.opentelemetry.io/otel/sdk/resource"

vendor/go.opentelemetry.io/otel/sdk/resource/env.go

@@ -0,0 +1,99 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"go.opentelemetry.io/otel/attribute"
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+)
+
+const (
+	// resourceAttrKey is the environment variable name OpenTelemetry Resource information will be read from.
+	resourceAttrKey = "OTEL_RESOURCE_ATTRIBUTES"
+
+	// svcNameKey is the environment variable name that Service Name information will be read from.
+	svcNameKey = "OTEL_SERVICE_NAME"
+)
+
+var (
+	// errMissingValue is returned when a resource value is missing.
+	errMissingValue = fmt.Errorf("%w: missing value", ErrPartialResource)
+)
+
+// fromEnv is a Detector that implements the Detector and collects
+// resources from environment.  This Detector is included as a
+// builtin.
+type fromEnv struct{}
+
+// compile time assertion that FromEnv implements Detector interface
+var _ Detector = fromEnv{}
+
+// Detect collects resources from environment
+func (fromEnv) Detect(context.Context) (*Resource, error) {
+	attrs := strings.TrimSpace(os.Getenv(resourceAttrKey))
+	svcName := strings.TrimSpace(os.Getenv(svcNameKey))
+
+	if attrs == "" && svcName == "" {
+		return Empty(), nil
+	}
+
+	var res *Resource
+
+	if svcName != "" {
+		res = NewSchemaless(semconv.ServiceNameKey.String(svcName))
+	}
+
+	r2, err := constructOTResources(attrs)
+
+	// Ensure that the resource with the service name from OTEL_SERVICE_NAME
+	// takes precedence, if it was defined.
+	res, err2 := Merge(r2, res)
+
+	if err == nil {
+		err = err2
+	} else if err2 != nil {
+		err = fmt.Errorf("detecting resources: %s", []string{err.Error(), err2.Error()})
+	}
+
+	return res, err
+}
+
+func constructOTResources(s string) (*Resource, error) {
+	if s == "" {
+		return Empty(), nil
+	}
+	pairs := strings.Split(s, ",")
+	attrs := []attribute.KeyValue{}
+	var invalid []string
+	for _, p := range pairs {
+		field := strings.SplitN(p, "=", 2)
+		if len(field) != 2 {
+			invalid = append(invalid, p)
+			continue
+		}
+		k, v := strings.TrimSpace(field[0]), strings.TrimSpace(field[1])
+		attrs = append(attrs, attribute.String(k, v))
+	}
+	var err error
+	if len(invalid) > 0 {
+		err = fmt.Errorf("%w: %v", errMissingValue, invalid)
+	}
+	return NewSchemaless(attrs...), err
+}

vendor/go.opentelemetry.io/otel/sdk/resource/os.go

@@ -0,0 +1,97 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+	"strings"
+
+	"go.opentelemetry.io/otel/attribute"
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+)
+
+type osDescriptionProvider func() (string, error)
+
+var defaultOSDescriptionProvider osDescriptionProvider = platformOSDescription
+
+var osDescription = defaultOSDescriptionProvider
+
+func setDefaultOSDescriptionProvider() {
+	setOSDescriptionProvider(defaultOSDescriptionProvider)
+}
+
+func setOSDescriptionProvider(osDescriptionProvider osDescriptionProvider) {
+	osDescription = osDescriptionProvider
+}
+
+type osTypeDetector struct{}
+type osDescriptionDetector struct{}
+
+// Detect returns a *Resource that describes the operating system type the
+// service is running on.
+func (osTypeDetector) Detect(ctx context.Context) (*Resource, error) {
+	osType := runtimeOS()
+
+	osTypeAttribute := mapRuntimeOSToSemconvOSType(osType)
+
+	return NewWithAttributes(
+		semconv.SchemaURL,
+		osTypeAttribute,
+	), nil
+}
+
+// Detect returns a *Resource that describes the operating system the
+// service is running on.
+func (osDescriptionDetector) Detect(ctx context.Context) (*Resource, error) {
+	description, err := osDescription()
+
+	if err != nil {
+		return nil, err
+	}
+
+	return NewWithAttributes(
+		semconv.SchemaURL,
+		semconv.OSDescriptionKey.String(description),
+	), nil
+}
+
+// mapRuntimeOSToSemconvOSType translates the OS name as provided by the Go runtime
+// into an OS type attribute with the corresponding value defined by the semantic
+// conventions. In case the provided OS name isn't mapped, it's transformed to lowercase
+// and used as the value for the returned OS type attribute.
+func mapRuntimeOSToSemconvOSType(osType string) attribute.KeyValue {
+	// the elements in this map are the intersection between
+	// available GOOS values and defined semconv OS types
+	osTypeAttributeMap := map[string]attribute.KeyValue{
+		"darwin":    semconv.OSTypeDarwin,
+		"dragonfly": semconv.OSTypeDragonflyBSD,
+		"freebsd":   semconv.OSTypeFreeBSD,
+		"linux":     semconv.OSTypeLinux,
+		"netbsd":    semconv.OSTypeNetBSD,
+		"openbsd":   semconv.OSTypeOpenBSD,
+		"solaris":   semconv.OSTypeSolaris,
+		"windows":   semconv.OSTypeWindows,
+	}
+
+	var osTypeAttribute attribute.KeyValue
+
+	if attr, ok := osTypeAttributeMap[osType]; ok {
+		osTypeAttribute = attr
+	} else {
+		osTypeAttribute = semconv.OSTypeKey.String(strings.ToLower(osType))
+	}
+
+	return osTypeAttribute
+}

vendor/go.opentelemetry.io/otel/sdk/resource/os_release_darwin.go

@@ -0,0 +1,102 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"encoding/xml"
+	"fmt"
+	"io"
+	"os"
+)
+
+type plist struct {
+	XMLName xml.Name `xml:"plist"`
+	Dict    dict     `xml:"dict"`
+}
+
+type dict struct {
+	Key    []string `xml:"key"`
+	String []string `xml:"string"`
+}
+
+// osRelease builds a string describing the operating system release based on the
+// contents of the property list (.plist) system files. If no .plist files are found,
+// or if the required properties to build the release description string are missing,
+// an empty string is returned instead. The generated string resembles the output of
+// the `sw_vers` commandline program, but in a single-line string. For more information
+// about the `sw_vers` program, see: https://www.unix.com/man-page/osx/1/SW_VERS.
+func osRelease() string {
+	file, err := getPlistFile()
+	if err != nil {
+		return ""
+	}
+
+	defer file.Close()
+
+	values, err := parsePlistFile(file)
+	if err != nil {
+		return ""
+	}
+
+	return buildOSRelease(values)
+}
+
+// getPlistFile returns a *os.File pointing to one of the well-known .plist files
+// available on macOS. If no file can be opened, it returns an error.
+func getPlistFile() (*os.File, error) {
+	return getFirstAvailableFile([]string{
+		"/System/Library/CoreServices/SystemVersion.plist",
+		"/System/Library/CoreServices/ServerVersion.plist",
+	})
+}
+
+// parsePlistFile process the file pointed by `file` as a .plist file and returns
+// a map with the key-values for each pair of correlated <key> and <string> elements
+// contained in it.
+func parsePlistFile(file io.Reader) (map[string]string, error) {
+	var v plist
+
+	err := xml.NewDecoder(file).Decode(&v)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(v.Dict.Key) != len(v.Dict.String) {
+		return nil, fmt.Errorf("the number of <key> and <string> elements doesn't match")
+	}
+
+	properties := make(map[string]string, len(v.Dict.Key))
+	for i, key := range v.Dict.Key {
+		properties[key] = v.Dict.String[i]
+	}
+
+	return properties, nil
+}
+
+// buildOSRelease builds a string describing the OS release based on the properties
+// available on the provided map. It tries to find the `ProductName`, `ProductVersion`
+// and `ProductBuildVersion` properties. If some of these properties are not found,
+// it returns an empty string.
+func buildOSRelease(properties map[string]string) string {
+	productName := properties["ProductName"]
+	productVersion := properties["ProductVersion"]
+	productBuildVersion := properties["ProductBuildVersion"]
+
+	if productName == "" || productVersion == "" || productBuildVersion == "" {
+		return ""
+	}
+
+	return fmt.Sprintf("%s %s (%s)", productName, productVersion, productBuildVersion)
+}

vendor/go.opentelemetry.io/otel/sdk/resource/os_release_unix.go

@@ -0,0 +1,154 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build aix || dragonfly || freebsd || linux || netbsd || openbsd || solaris || zos
+// +build aix dragonfly freebsd linux netbsd openbsd solaris zos
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+)
+
+// osRelease builds a string describing the operating system release based on the
+// properties of the os-release file. If no os-release file is found, or if the
+// required properties to build the release description string are missing, an empty
+// string is returned instead. For more information about os-release files, see:
+// https://www.freedesktop.org/software/systemd/man/os-release.html
+func osRelease() string {
+	file, err := getOSReleaseFile()
+	if err != nil {
+		return ""
+	}
+
+	defer file.Close()
+
+	values := parseOSReleaseFile(file)
+
+	return buildOSRelease(values)
+}
+
+// getOSReleaseFile returns a *os.File pointing to one of the well-known os-release
+// files, according to their order of preference. If no file can be opened, it
+// returns an error.
+func getOSReleaseFile() (*os.File, error) {
+	return getFirstAvailableFile([]string{"/etc/os-release", "/usr/lib/os-release"})
+}
+
+// parseOSReleaseFile process the file pointed by `file` as an os-release file and
+// returns a map with the key-values contained in it. Empty lines or lines starting
+// with a '#' character are ignored, as well as lines with the missing key=value
+// separator. Values are unquoted and unescaped.
+func parseOSReleaseFile(file io.Reader) map[string]string {
+	values := make(map[string]string)
+	scanner := bufio.NewScanner(file)
+
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		if skip(line) {
+			continue
+		}
+
+		key, value, ok := parse(line)
+		if ok {
+			values[key] = value
+		}
+	}
+
+	return values
+}
+
+// skip returns true if the line is blank or starts with a '#' character, and
+// therefore should be skipped from processing.
+func skip(line string) bool {
+	line = strings.TrimSpace(line)
+
+	return len(line) == 0 || strings.HasPrefix(line, "#")
+}
+
+// parse attempts to split the provided line on the first '=' character, and then
+// sanitize each side of the split before returning them as a key-value pair.
+func parse(line string) (string, string, bool) {
+	parts := strings.SplitN(line, "=", 2)
+
+	if len(parts) != 2 || len(parts[0]) == 0 {
+		return "", "", false
+	}
+
+	key := strings.TrimSpace(parts[0])
+	value := unescape(unquote(strings.TrimSpace(parts[1])))
+
+	return key, value, true
+}
+
+// unquote checks whether the string `s` is quoted with double or single quotes
+// and, if so, returns a version of the string without them. Otherwise it returns
+// the provided string unchanged.
+func unquote(s string) string {
+	if len(s) < 2 {
+		return s
+	}
+
+	if (s[0] == '"' || s[0] == '\'') && s[0] == s[len(s)-1] {
+		return s[1 : len(s)-1]
+	}
+
+	return s
+}
+
+// unescape removes the `\` prefix from some characters that are expected
+// to have it added in front of them for escaping purposes.
+func unescape(s string) string {
+	return strings.NewReplacer(
+		`\$`, `$`,
+		`\"`, `"`,
+		`\'`, `'`,
+		`\\`, `\`,
+		"\\`", "`",
+	).Replace(s)
+}
+
+// buildOSRelease builds a string describing the OS release based on the properties
+// available on the provided map. It favors a combination of the `NAME` and `VERSION`
+// properties as first option (falling back to `VERSION_ID` if `VERSION` isn't
+// found), and using `PRETTY_NAME` alone if some of the previous are not present. If
+// none of these properties are found, it returns an empty string.
+//
+// The rationale behind not using `PRETTY_NAME` as first choice was that, for some
+// Linux distributions, it doesn't include the same detail that can be found on the
+// individual `NAME` and `VERSION` properties, and combining `PRETTY_NAME` with
+// other properties can produce "pretty" redundant strings in some cases.
+func buildOSRelease(values map[string]string) string {
+	var osRelease string
+
+	name := values["NAME"]
+	version := values["VERSION"]
+
+	if version == "" {
+		version = values["VERSION_ID"]
+	}
+
+	if name != "" && version != "" {
+		osRelease = fmt.Sprintf("%s %s", name, version)
+	} else {
+		osRelease = values["PRETTY_NAME"]
+	}
+
+	return osRelease
+}

vendor/go.opentelemetry.io/otel/sdk/resource/os_unix.go

@@ -0,0 +1,100 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || zos
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris zos
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+
+	"golang.org/x/sys/unix"
+)
+
+type unameProvider func(buf *unix.Utsname) (err error)
+
+var defaultUnameProvider unameProvider = unix.Uname
+
+var currentUnameProvider = defaultUnameProvider
+
+func setDefaultUnameProvider() {
+	setUnameProvider(defaultUnameProvider)
+}
+
+func setUnameProvider(unameProvider unameProvider) {
+	currentUnameProvider = unameProvider
+}
+
+// platformOSDescription returns a human readable OS version information string.
+// The final string combines OS release information (where available) and the
+// result of the `uname` system call.
+func platformOSDescription() (string, error) {
+	uname, err := uname()
+	if err != nil {
+		return "", err
+	}
+
+	osRelease := osRelease()
+	if osRelease != "" {
+		return fmt.Sprintf("%s (%s)", osRelease, uname), nil
+	}
+
+	return uname, nil
+}
+
+// uname issues a uname(2) system call (or equivalent on systems which doesn't
+// have one) and formats the output in a single string, similar to the output
+// of the `uname` commandline program. The final string resembles the one
+// obtained with a call to `uname -snrvm`.
+func uname() (string, error) {
+	var utsName unix.Utsname
+
+	err := currentUnameProvider(&utsName)
+	if err != nil {
+		return "", err
+	}
+
+	return fmt.Sprintf("%s %s %s %s %s",
+		charsToString(utsName.Sysname[:]),
+		charsToString(utsName.Nodename[:]),
+		charsToString(utsName.Release[:]),
+		charsToString(utsName.Version[:]),
+		charsToString(utsName.Machine[:]),
+	), nil
+}
+
+// charsToString converts a C-like null-terminated char array to a Go string.
+func charsToString(charArray []byte) string {
+	if i := bytes.IndexByte(charArray, 0); i >= 0 {
+		charArray = charArray[:i]
+	}
+
+	return string(charArray)
+}
+
+// getFirstAvailableFile returns an *os.File of the first available
+// file from a list of candidate file paths.
+func getFirstAvailableFile(candidates []string) (*os.File, error) {
+	for _, c := range candidates {
+		file, err := os.Open(c)
+		if err == nil {
+			return file, nil
+		}
+	}
+
+	return nil, fmt.Errorf("no candidate file available: %v", candidates)
+}

vendor/go.opentelemetry.io/otel/sdk/resource/os_unsupported.go

@@ -0,0 +1,34 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !aix
+// +build !darwin
+// +build !dragonfly
+// +build !freebsd
+// +build !linux
+// +build !netbsd
+// +build !openbsd
+// +build !solaris
+// +build !windows
+// +build !zos
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+// platformOSDescription is a placeholder implementation for OSes
+// for which this project currently doesn't support os.description
+// attribute detection. See build tags declaration early on this file
+// for a list of unsupported OSes.
+func platformOSDescription() (string, error) {
+	return "<unknown>", nil
+}

vendor/go.opentelemetry.io/otel/sdk/resource/os_windows.go

@@ -0,0 +1,101 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"fmt"
+	"strconv"
+
+	"golang.org/x/sys/windows/registry"
+)
+
+// platformOSDescription returns a human readable OS version information string.
+// It does so by querying registry values under the
+// `SOFTWARE\Microsoft\Windows NT\CurrentVersion` key. The final string
+// resembles the one displayed by the Version Reporter Applet (winver.exe).
+func platformOSDescription() (string, error) {
+	k, err := registry.OpenKey(
+		registry.LOCAL_MACHINE, `SOFTWARE\Microsoft\Windows NT\CurrentVersion`, registry.QUERY_VALUE)
+
+	if err != nil {
+		return "", err
+	}
+
+	defer k.Close()
+
+	var (
+		productName               = readProductName(k)
+		displayVersion            = readDisplayVersion(k)
+		releaseID                 = readReleaseID(k)
+		currentMajorVersionNumber = readCurrentMajorVersionNumber(k)
+		currentMinorVersionNumber = readCurrentMinorVersionNumber(k)
+		currentBuildNumber        = readCurrentBuildNumber(k)
+		ubr                       = readUBR(k)
+	)
+
+	if displayVersion != "" {
+		displayVersion += " "
+	}
+
+	return fmt.Sprintf("%s %s(%s) [Version %s.%s.%s.%s]",
+		productName,
+		displayVersion,
+		releaseID,
+		currentMajorVersionNumber,
+		currentMinorVersionNumber,
+		currentBuildNumber,
+		ubr,
+	), nil
+}
+
+func getStringValue(name string, k registry.Key) string {
+	value, _, _ := k.GetStringValue(name)
+
+	return value
+}
+
+func getIntegerValue(name string, k registry.Key) uint64 {
+	value, _, _ := k.GetIntegerValue(name)
+
+	return value
+}
+
+func readProductName(k registry.Key) string {
+	return getStringValue("ProductName", k)
+}
+
+func readDisplayVersion(k registry.Key) string {
+	return getStringValue("DisplayVersion", k)
+}
+
+func readReleaseID(k registry.Key) string {
+	return getStringValue("ReleaseID", k)
+}
+
+func readCurrentMajorVersionNumber(k registry.Key) string {
+	return strconv.FormatUint(getIntegerValue("CurrentMajorVersionNumber", k), 10)
+}
+
+func readCurrentMinorVersionNumber(k registry.Key) string {
+	return strconv.FormatUint(getIntegerValue("CurrentMinorVersionNumber", k), 10)
+}
+
+func readCurrentBuildNumber(k registry.Key) string {
+	return getStringValue("CurrentBuildNumber", k)
+}
+
+func readUBR(k registry.Key) string {
+	return strconv.FormatUint(getIntegerValue("UBR", k), 10)
+}

vendor/go.opentelemetry.io/otel/sdk/resource/process.go

@@ -0,0 +1,180 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/user"
+	"path/filepath"
+	"runtime"
+
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+)
+
+type pidProvider func() int
+type executablePathProvider func() (string, error)
+type commandArgsProvider func() []string
+type ownerProvider func() (*user.User, error)
+type runtimeNameProvider func() string
+type runtimeVersionProvider func() string
+type runtimeOSProvider func() string
+type runtimeArchProvider func() string
+
+var (
+	defaultPidProvider            pidProvider            = os.Getpid
+	defaultExecutablePathProvider executablePathProvider = os.Executable
+	defaultCommandArgsProvider    commandArgsProvider    = func() []string { return os.Args }
+	defaultOwnerProvider          ownerProvider          = user.Current
+	defaultRuntimeNameProvider    runtimeNameProvider    = func() string {
+		if runtime.Compiler == "gc" {
+			return "go"
+		}
+		return runtime.Compiler
+	}
+	defaultRuntimeVersionProvider runtimeVersionProvider = runtime.Version
+	defaultRuntimeOSProvider      runtimeOSProvider      = func() string { return runtime.GOOS }
+	defaultRuntimeArchProvider    runtimeArchProvider    = func() string { return runtime.GOARCH }
+)
+
+var (
+	pid            = defaultPidProvider
+	executablePath = defaultExecutablePathProvider
+	commandArgs    = defaultCommandArgsProvider
+	owner          = defaultOwnerProvider
+	runtimeName    = defaultRuntimeNameProvider
+	runtimeVersion = defaultRuntimeVersionProvider
+	runtimeOS      = defaultRuntimeOSProvider
+	runtimeArch    = defaultRuntimeArchProvider
+)
+
+func setDefaultOSProviders() {
+	setOSProviders(
+		defaultPidProvider,
+		defaultExecutablePathProvider,
+		defaultCommandArgsProvider,
+	)
+}
+
+func setOSProviders(
+	pidProvider pidProvider,
+	executablePathProvider executablePathProvider,
+	commandArgsProvider commandArgsProvider,
+) {
+	pid = pidProvider
+	executablePath = executablePathProvider
+	commandArgs = commandArgsProvider
+}
+
+func setDefaultRuntimeProviders() {
+	setRuntimeProviders(
+		defaultRuntimeNameProvider,
+		defaultRuntimeVersionProvider,
+		defaultRuntimeOSProvider,
+		defaultRuntimeArchProvider,
+	)
+}
+
+func setRuntimeProviders(
+	runtimeNameProvider runtimeNameProvider,
+	runtimeVersionProvider runtimeVersionProvider,
+	runtimeOSProvider runtimeOSProvider,
+	runtimeArchProvider runtimeArchProvider,
+) {
+	runtimeName = runtimeNameProvider
+	runtimeVersion = runtimeVersionProvider
+	runtimeOS = runtimeOSProvider
+	runtimeArch = runtimeArchProvider
+}
+
+func setDefaultUserProviders() {
+	setUserProviders(defaultOwnerProvider)
+}
+
+func setUserProviders(ownerProvider ownerProvider) {
+	owner = ownerProvider
+}
+
+type processPIDDetector struct{}
+type processExecutableNameDetector struct{}
+type processExecutablePathDetector struct{}
+type processCommandArgsDetector struct{}
+type processOwnerDetector struct{}
+type processRuntimeNameDetector struct{}
+type processRuntimeVersionDetector struct{}
+type processRuntimeDescriptionDetector struct{}
+
+// Detect returns a *Resource that describes the process identifier (PID) of the
+// executing process.
+func (processPIDDetector) Detect(ctx context.Context) (*Resource, error) {
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessPIDKey.Int(pid())), nil
+}
+
+// Detect returns a *Resource that describes the name of the process executable.
+func (processExecutableNameDetector) Detect(ctx context.Context) (*Resource, error) {
+	executableName := filepath.Base(commandArgs()[0])
+
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessExecutableNameKey.String(executableName)), nil
+}
+
+// Detect returns a *Resource that describes the full path of the process executable.
+func (processExecutablePathDetector) Detect(ctx context.Context) (*Resource, error) {
+	executablePath, err := executablePath()
+	if err != nil {
+		return nil, err
+	}
+
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessExecutablePathKey.String(executablePath)), nil
+}
+
+// Detect returns a *Resource that describes all the command arguments as received
+// by the process.
+func (processCommandArgsDetector) Detect(ctx context.Context) (*Resource, error) {
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessCommandArgsKey.StringSlice(commandArgs())), nil
+}
+
+// Detect returns a *Resource that describes the username of the user that owns the
+// process.
+func (processOwnerDetector) Detect(ctx context.Context) (*Resource, error) {
+	owner, err := owner()
+	if err != nil {
+		return nil, err
+	}
+
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessOwnerKey.String(owner.Username)), nil
+}
+
+// Detect returns a *Resource that describes the name of the compiler used to compile
+// this process image.
+func (processRuntimeNameDetector) Detect(ctx context.Context) (*Resource, error) {
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessRuntimeNameKey.String(runtimeName())), nil
+}
+
+// Detect returns a *Resource that describes the version of the runtime of this process.
+func (processRuntimeVersionDetector) Detect(ctx context.Context) (*Resource, error) {
+	return NewWithAttributes(semconv.SchemaURL, semconv.ProcessRuntimeVersionKey.String(runtimeVersion())), nil
+}
+
+// Detect returns a *Resource that describes the runtime of this process.
+func (processRuntimeDescriptionDetector) Detect(ctx context.Context) (*Resource, error) {
+	runtimeDescription := fmt.Sprintf(
+		"go version %s %s/%s", runtimeVersion(), runtimeOS(), runtimeArch())
+
+	return NewWithAttributes(
+		semconv.SchemaURL,
+		semconv.ProcessRuntimeDescriptionKey.String(runtimeDescription),
+	), nil
+}

vendor/go.opentelemetry.io/otel/sdk/resource/resource.go

@@ -0,0 +1,280 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package resource // import "go.opentelemetry.io/otel/sdk/resource"
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+)
+
+// Resource describes an entity about which identifying information
+// and metadata is exposed.  Resource is an immutable object,
+// equivalent to a map from key to unique value.
+//
+// Resources should be passed and stored as pointers
+// (`*resource.Resource`).  The `nil` value is equivalent to an empty
+// Resource.
+type Resource struct {
+	attrs     attribute.Set
+	schemaURL string
+}
+
+var (
+	emptyResource       Resource
+	defaultResource     *Resource
+	defaultResourceOnce sync.Once
+)
+
+var errMergeConflictSchemaURL = errors.New("cannot merge resource due to conflicting Schema URL")
+
+// New returns a Resource combined from the user-provided detectors.
+func New(ctx context.Context, opts ...Option) (*Resource, error) {
+	cfg := config{}
+	for _, opt := range opts {
+		cfg = opt.apply(cfg)
+	}
+
+	resource, err := Detect(ctx, cfg.detectors...)
+
+	var err2 error
+	resource, err2 = Merge(resource, &Resource{schemaURL: cfg.schemaURL})
+	if err == nil {
+		err = err2
+	} else if err2 != nil {
+		err = fmt.Errorf("detecting resources: %s", []string{err.Error(), err2.Error()})
+	}
+
+	return resource, err
+}
+
+// NewWithAttributes creates a resource from attrs and associates the resource with a
+// schema URL. If attrs contains duplicate keys, the last value will be used. If attrs
+// contains any invalid items those items will be dropped. The attrs are assumed to be
+// in a schema identified by schemaURL.
+func NewWithAttributes(schemaURL string, attrs ...attribute.KeyValue) *Resource {
+	resource := NewSchemaless(attrs...)
+	resource.schemaURL = schemaURL
+	return resource
+}
+
+// NewSchemaless creates a resource from attrs. If attrs contains duplicate keys,
+// the last value will be used. If attrs contains any invalid items those items will
+// be dropped. The resource will not be associated with a schema URL. If the schema
+// of the attrs is known use NewWithAttributes instead.
+func NewSchemaless(attrs ...attribute.KeyValue) *Resource {
+	if len(attrs) == 0 {
+		return &emptyResource
+	}
+
+	// Ensure attributes comply with the specification:
+	// https://github.com/open-telemetry/opentelemetry-specification/blob/v1.0.1/specification/common/common.md#attributes
+	s, _ := attribute.NewSetWithFiltered(attrs, func(kv attribute.KeyValue) bool {
+		return kv.Valid()
+	})
+
+	// If attrs only contains invalid entries do not allocate a new resource.
+	if s.Len() == 0 {
+		return &emptyResource
+	}
+
+	return &Resource{attrs: s} //nolint
+}
+
+// String implements the Stringer interface and provides a
+// human-readable form of the resource.
+//
+// Avoid using this representation as the key in a map of resources,
+// use Equivalent() as the key instead.
+func (r *Resource) String() string {
+	if r == nil {
+		return ""
+	}
+	return r.attrs.Encoded(attribute.DefaultEncoder())
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this exporter.
+func (r *Resource) MarshalLog() interface{} {
+	return struct {
+		Attributes attribute.Set
+		SchemaURL  string
+	}{
+		Attributes: r.attrs,
+		SchemaURL:  r.schemaURL,
+	}
+}
+
+// Attributes returns a copy of attributes from the resource in a sorted order.
+// To avoid allocating a new slice, use an iterator.
+func (r *Resource) Attributes() []attribute.KeyValue {
+	if r == nil {
+		r = Empty()
+	}
+	return r.attrs.ToSlice()
+}
+
+func (r *Resource) SchemaURL() string {
+	if r == nil {
+		return ""
+	}
+	return r.schemaURL
+}
+
+// Iter returns an iterator of the Resource attributes.
+// This is ideal to use if you do not want a copy of the attributes.
+func (r *Resource) Iter() attribute.Iterator {
+	if r == nil {
+		r = Empty()
+	}
+	return r.attrs.Iter()
+}
+
+// Equal returns true when a Resource is equivalent to this Resource.
+func (r *Resource) Equal(eq *Resource) bool {
+	if r == nil {
+		r = Empty()
+	}
+	if eq == nil {
+		eq = Empty()
+	}
+	return r.Equivalent() == eq.Equivalent()
+}
+
+// Merge creates a new resource by combining resource a and b.
+//
+// If there are common keys between resource a and b, then the value
+// from resource b will overwrite the value from resource a, even
+// if resource b's value is empty.
+//
+// The SchemaURL of the resources will be merged according to the spec rules:
+// https://github.com/open-telemetry/opentelemetry-specification/blob/bad49c714a62da5493f2d1d9bafd7ebe8c8ce7eb/specification/resource/sdk.md#merge
+// If the resources have different non-empty schemaURL an empty resource and an error
+// will be returned.
+func Merge(a, b *Resource) (*Resource, error) {
+	if a == nil && b == nil {
+		return Empty(), nil
+	}
+	if a == nil {
+		return b, nil
+	}
+	if b == nil {
+		return a, nil
+	}
+
+	// Merge the schema URL.
+	var schemaURL string
+	if a.schemaURL == "" {
+		schemaURL = b.schemaURL
+	} else if b.schemaURL == "" {
+		schemaURL = a.schemaURL
+	} else if a.schemaURL == b.schemaURL {
+		schemaURL = a.schemaURL
+	} else {
+		return Empty(), errMergeConflictSchemaURL
+	}
+
+	// Note: 'b' attributes will overwrite 'a' with last-value-wins in attribute.Key()
+	// Meaning this is equivalent to: append(a.Attributes(), b.Attributes()...)
+	mi := attribute.NewMergeIterator(b.Set(), a.Set())
+	combine := make([]attribute.KeyValue, 0, a.Len()+b.Len())
+	for mi.Next() {
+		combine = append(combine, mi.Label())
+	}
+	merged := NewWithAttributes(schemaURL, combine...)
+	return merged, nil
+}
+
+// Empty returns an instance of Resource with no attributes. It is
+// equivalent to a `nil` Resource.
+func Empty() *Resource {
+	return &emptyResource
+}
+
+// Default returns an instance of Resource with a default
+// "service.name" and OpenTelemetrySDK attributes.
+func Default() *Resource {
+	defaultResourceOnce.Do(func() {
+		var err error
+		defaultResource, err = Detect(
+			context.Background(),
+			defaultServiceNameDetector{},
+			fromEnv{},
+			telemetrySDK{},
+		)
+		if err != nil {
+			otel.Handle(err)
+		}
+		// If Detect did not return a valid resource, fall back to emptyResource.
+		if defaultResource == nil {
+			defaultResource = &emptyResource
+		}
+	})
+	return defaultResource
+}
+
+// Environment returns an instance of Resource with attributes
+// extracted from the OTEL_RESOURCE_ATTRIBUTES environment variable.
+func Environment() *Resource {
+	detector := &fromEnv{}
+	resource, err := detector.Detect(context.Background())
+	if err != nil {
+		otel.Handle(err)
+	}
+	return resource
+}
+
+// Equivalent returns an object that can be compared for equality
+// between two resources. This value is suitable for use as a key in
+// a map.
+func (r *Resource) Equivalent() attribute.Distinct {
+	return r.Set().Equivalent()
+}
+
+// Set returns the equivalent *attribute.Set of this resource's attributes.
+func (r *Resource) Set() *attribute.Set {
+	if r == nil {
+		r = Empty()
+	}
+	return &r.attrs
+}
+
+// MarshalJSON encodes the resource attributes as a JSON list of { "Key":
+// "...", "Value": ... } pairs in order sorted by key.
+func (r *Resource) MarshalJSON() ([]byte, error) {
+	if r == nil {
+		r = Empty()
+	}
+	return r.attrs.MarshalJSON()
+}
+
+// Len returns the number of unique key-values in this Resource.
+func (r *Resource) Len() int {
+	if r == nil {
+		return 0
+	}
+	return r.attrs.Len()
+}
+
+// Encoded returns an encoded representation of the resource.
+func (r *Resource) Encoded(enc attribute.Encoder) string {
+	if r == nil {
+		return ""
+	}
+	return r.attrs.Encoded(enc)
+}

vendor/go.opentelemetry.io/otel/sdk/trace/batch_span_processor.go

@@ -0,0 +1,396 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/internal/global"
+	"go.opentelemetry.io/otel/sdk/internal/env"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// Defaults for BatchSpanProcessorOptions.
+const (
+	DefaultMaxQueueSize       = 2048
+	DefaultScheduleDelay      = 5000
+	DefaultExportTimeout      = 30000
+	DefaultMaxExportBatchSize = 512
+)
+
+type BatchSpanProcessorOption func(o *BatchSpanProcessorOptions)
+
+type BatchSpanProcessorOptions struct {
+	// MaxQueueSize is the maximum queue size to buffer spans for delayed processing. If the
+	// queue gets full it drops the spans. Use BlockOnQueueFull to change this behavior.
+	// The default value of MaxQueueSize is 2048.
+	MaxQueueSize int
+
+	// BatchTimeout is the maximum duration for constructing a batch. Processor
+	// forcefully sends available spans when timeout is reached.
+	// The default value of BatchTimeout is 5000 msec.
+	BatchTimeout time.Duration
+
+	// ExportTimeout specifies the maximum duration for exporting spans. If the timeout
+	// is reached, the export will be cancelled.
+	// The default value of ExportTimeout is 30000 msec.
+	ExportTimeout time.Duration
+
+	// MaxExportBatchSize is the maximum number of spans to process in a single batch.
+	// If there are more than one batch worth of spans then it processes multiple batches
+	// of spans one batch after the other without any delay.
+	// The default value of MaxExportBatchSize is 512.
+	MaxExportBatchSize int
+
+	// BlockOnQueueFull blocks onEnd() and onStart() method if the queue is full
+	// AND if BlockOnQueueFull is set to true.
+	// Blocking option should be used carefully as it can severely affect the performance of an
+	// application.
+	BlockOnQueueFull bool
+}
+
+// batchSpanProcessor is a SpanProcessor that batches asynchronously-received
+// spans and sends them to a trace.Exporter when complete.
+type batchSpanProcessor struct {
+	e SpanExporter
+	o BatchSpanProcessorOptions
+
+	queue   chan ReadOnlySpan
+	dropped uint32
+
+	batch      []ReadOnlySpan
+	batchMutex sync.Mutex
+	timer      *time.Timer
+	stopWait   sync.WaitGroup
+	stopOnce   sync.Once
+	stopCh     chan struct{}
+}
+
+var _ SpanProcessor = (*batchSpanProcessor)(nil)
+
+// NewBatchSpanProcessor creates a new SpanProcessor that will send completed
+// span batches to the exporter with the supplied options.
+//
+// If the exporter is nil, the span processor will preform no action.
+func NewBatchSpanProcessor(exporter SpanExporter, options ...BatchSpanProcessorOption) SpanProcessor {
+	maxQueueSize := env.BatchSpanProcessorMaxQueueSize(DefaultMaxQueueSize)
+	maxExportBatchSize := env.BatchSpanProcessorMaxExportBatchSize(DefaultMaxExportBatchSize)
+
+	if maxExportBatchSize > maxQueueSize {
+		if DefaultMaxExportBatchSize > maxQueueSize {
+			maxExportBatchSize = maxQueueSize
+		} else {
+			maxExportBatchSize = DefaultMaxExportBatchSize
+		}
+	}
+
+	o := BatchSpanProcessorOptions{
+		BatchTimeout:       time.Duration(env.BatchSpanProcessorScheduleDelay(DefaultScheduleDelay)) * time.Millisecond,
+		ExportTimeout:      time.Duration(env.BatchSpanProcessorExportTimeout(DefaultExportTimeout)) * time.Millisecond,
+		MaxQueueSize:       maxQueueSize,
+		MaxExportBatchSize: maxExportBatchSize,
+	}
+	for _, opt := range options {
+		opt(&o)
+	}
+	bsp := &batchSpanProcessor{
+		e:      exporter,
+		o:      o,
+		batch:  make([]ReadOnlySpan, 0, o.MaxExportBatchSize),
+		timer:  time.NewTimer(o.BatchTimeout),
+		queue:  make(chan ReadOnlySpan, o.MaxQueueSize),
+		stopCh: make(chan struct{}),
+	}
+
+	bsp.stopWait.Add(1)
+	go func() {
+		defer bsp.stopWait.Done()
+		bsp.processQueue()
+		bsp.drainQueue()
+	}()
+
+	return bsp
+}
+
+// OnStart method does nothing.
+func (bsp *batchSpanProcessor) OnStart(parent context.Context, s ReadWriteSpan) {}
+
+// OnEnd method enqueues a ReadOnlySpan for later processing.
+func (bsp *batchSpanProcessor) OnEnd(s ReadOnlySpan) {
+	// Do not enqueue spans if we are just going to drop them.
+	if bsp.e == nil {
+		return
+	}
+	bsp.enqueue(s)
+}
+
+// Shutdown flushes the queue and waits until all spans are processed.
+// It only executes once. Subsequent call does nothing.
+func (bsp *batchSpanProcessor) Shutdown(ctx context.Context) error {
+	var err error
+	bsp.stopOnce.Do(func() {
+		wait := make(chan struct{})
+		go func() {
+			close(bsp.stopCh)
+			bsp.stopWait.Wait()
+			if bsp.e != nil {
+				if err := bsp.e.Shutdown(ctx); err != nil {
+					otel.Handle(err)
+				}
+			}
+			close(wait)
+		}()
+		// Wait until the wait group is done or the context is cancelled
+		select {
+		case <-wait:
+		case <-ctx.Done():
+			err = ctx.Err()
+		}
+	})
+	return err
+}
+
+type forceFlushSpan struct {
+	ReadOnlySpan
+	flushed chan struct{}
+}
+
+func (f forceFlushSpan) SpanContext() trace.SpanContext {
+	return trace.NewSpanContext(trace.SpanContextConfig{TraceFlags: trace.FlagsSampled})
+}
+
+// ForceFlush exports all ended spans that have not yet been exported.
+func (bsp *batchSpanProcessor) ForceFlush(ctx context.Context) error {
+	var err error
+	if bsp.e != nil {
+		flushCh := make(chan struct{})
+		if bsp.enqueueBlockOnQueueFull(ctx, forceFlushSpan{flushed: flushCh}, true) {
+			select {
+			case <-flushCh:
+				// Processed any items in queue prior to ForceFlush being called
+			case <-ctx.Done():
+				return ctx.Err()
+			}
+		}
+
+		wait := make(chan error)
+		go func() {
+			wait <- bsp.exportSpans(ctx)
+			close(wait)
+		}()
+		// Wait until the export is finished or the context is cancelled/timed out
+		select {
+		case err = <-wait:
+		case <-ctx.Done():
+			err = ctx.Err()
+		}
+	}
+	return err
+}
+
+func WithMaxQueueSize(size int) BatchSpanProcessorOption {
+	return func(o *BatchSpanProcessorOptions) {
+		o.MaxQueueSize = size
+	}
+}
+
+func WithMaxExportBatchSize(size int) BatchSpanProcessorOption {
+	return func(o *BatchSpanProcessorOptions) {
+		o.MaxExportBatchSize = size
+	}
+}
+
+func WithBatchTimeout(delay time.Duration) BatchSpanProcessorOption {
+	return func(o *BatchSpanProcessorOptions) {
+		o.BatchTimeout = delay
+	}
+}
+
+func WithExportTimeout(timeout time.Duration) BatchSpanProcessorOption {
+	return func(o *BatchSpanProcessorOptions) {
+		o.ExportTimeout = timeout
+	}
+}
+
+func WithBlocking() BatchSpanProcessorOption {
+	return func(o *BatchSpanProcessorOptions) {
+		o.BlockOnQueueFull = true
+	}
+}
+
+// exportSpans is a subroutine of processing and draining the queue.
+func (bsp *batchSpanProcessor) exportSpans(ctx context.Context) error {
+
+	bsp.timer.Reset(bsp.o.BatchTimeout)
+
+	bsp.batchMutex.Lock()
+	defer bsp.batchMutex.Unlock()
+
+	if bsp.o.ExportTimeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, bsp.o.ExportTimeout)
+		defer cancel()
+	}
+
+	if l := len(bsp.batch); l > 0 {
+		global.Debug("exporting spans", "count", len(bsp.batch), "total_dropped", atomic.LoadUint32(&bsp.dropped))
+		err := bsp.e.ExportSpans(ctx, bsp.batch)
+
+		// A new batch is always created after exporting, even if the batch failed to be exported.
+		//
+		// It is up to the exporter to implement any type of retry logic if a batch is failing
+		// to be exported, since it is specific to the protocol and backend being sent to.
+		bsp.batch = bsp.batch[:0]
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// processQueue removes spans from the `queue` channel until processor
+// is shut down. It calls the exporter in batches of up to MaxExportBatchSize
+// waiting up to BatchTimeout to form a batch.
+func (bsp *batchSpanProcessor) processQueue() {
+	defer bsp.timer.Stop()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	for {
+		select {
+		case <-bsp.stopCh:
+			return
+		case <-bsp.timer.C:
+			if err := bsp.exportSpans(ctx); err != nil {
+				otel.Handle(err)
+			}
+		case sd := <-bsp.queue:
+			if ffs, ok := sd.(forceFlushSpan); ok {
+				close(ffs.flushed)
+				continue
+			}
+			bsp.batchMutex.Lock()
+			bsp.batch = append(bsp.batch, sd)
+			shouldExport := len(bsp.batch) >= bsp.o.MaxExportBatchSize
+			bsp.batchMutex.Unlock()
+			if shouldExport {
+				if !bsp.timer.Stop() {
+					<-bsp.timer.C
+				}
+				if err := bsp.exportSpans(ctx); err != nil {
+					otel.Handle(err)
+				}
+			}
+		}
+	}
+}
+
+// drainQueue awaits the any caller that had added to bsp.stopWait
+// to finish the enqueue, then exports the final batch.
+func (bsp *batchSpanProcessor) drainQueue() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	for {
+		select {
+		case sd := <-bsp.queue:
+			if sd == nil {
+				if err := bsp.exportSpans(ctx); err != nil {
+					otel.Handle(err)
+				}
+				return
+			}
+
+			bsp.batchMutex.Lock()
+			bsp.batch = append(bsp.batch, sd)
+			shouldExport := len(bsp.batch) == bsp.o.MaxExportBatchSize
+			bsp.batchMutex.Unlock()
+
+			if shouldExport {
+				if err := bsp.exportSpans(ctx); err != nil {
+					otel.Handle(err)
+				}
+			}
+		default:
+			close(bsp.queue)
+		}
+	}
+}
+
+func (bsp *batchSpanProcessor) enqueue(sd ReadOnlySpan) {
+	bsp.enqueueBlockOnQueueFull(context.TODO(), sd, bsp.o.BlockOnQueueFull)
+}
+
+func (bsp *batchSpanProcessor) enqueueBlockOnQueueFull(ctx context.Context, sd ReadOnlySpan, block bool) bool {
+	if !sd.SpanContext().IsSampled() {
+		return false
+	}
+
+	// This ensures the bsp.queue<- below does not panic as the
+	// processor shuts down.
+	defer func() {
+		x := recover()
+		switch err := x.(type) {
+		case nil:
+			return
+		case runtime.Error:
+			if err.Error() == "send on closed channel" {
+				return
+			}
+		}
+		panic(x)
+	}()
+
+	select {
+	case <-bsp.stopCh:
+		return false
+	default:
+	}
+
+	if block {
+		select {
+		case bsp.queue <- sd:
+			return true
+		case <-ctx.Done():
+			return false
+		}
+	}
+
+	select {
+	case bsp.queue <- sd:
+		return true
+	default:
+		atomic.AddUint32(&bsp.dropped, 1)
+	}
+	return false
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this exporter.
+func (bsp *batchSpanProcessor) MarshalLog() interface{} {
+	return struct {
+		Type         string
+		SpanExporter SpanExporter
+		Config       BatchSpanProcessorOptions
+	}{
+		Type:         "BatchSpanProcessor",
+		SpanExporter: bsp.e,
+		Config:       bsp.o,
+	}
+}

vendor/go.opentelemetry.io/otel/sdk/trace/doc.go

@@ -0,0 +1,21 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package trace contains support for OpenTelemetry distributed tracing.
+
+The following assumes a basic familiarity with OpenTelemetry concepts.
+See https://opentelemetry.io.
+*/
+package trace // import "go.opentelemetry.io/otel/sdk/trace"

vendor/go.opentelemetry.io/otel/sdk/trace/event.go

@@ -0,0 +1,37 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"time"
+
+	"go.opentelemetry.io/otel/attribute"
+)
+
+// Event is a thing that happened during a Span's lifetime.
+type Event struct {
+	// Name is the name of this event
+	Name string
+
+	// Attributes describe the aspects of the event.
+	Attributes []attribute.KeyValue
+
+	// DroppedAttributeCount is the number of attributes that were not
+	// recorded due to configured limits being reached.
+	DroppedAttributeCount int
+
+	// Time at which this event was recorded.
+	Time time.Time
+}

vendor/go.opentelemetry.io/otel/sdk/trace/evictedqueue.go

@@ -0,0 +1,44 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+// evictedQueue is a FIFO queue with a configurable capacity.
+type evictedQueue struct {
+	queue        []interface{}
+	capacity     int
+	droppedCount int
+}
+
+func newEvictedQueue(capacity int) evictedQueue {
+	// Do not pre-allocate queue, do this lazily.
+	return evictedQueue{capacity: capacity}
+}
+
+// add adds value to the evictedQueue eq. If eq is at capacity, the oldest
+// queued value will be discarded and the drop count incremented.
+func (eq *evictedQueue) add(value interface{}) {
+	if eq.capacity == 0 {
+		eq.droppedCount++
+		return
+	}
+
+	if eq.capacity > 0 && len(eq.queue) == eq.capacity {
+		// Drop first-in while avoiding allocating more capacity to eq.queue.
+		copy(eq.queue[:eq.capacity-1], eq.queue[1:])
+		eq.queue = eq.queue[:eq.capacity-1]
+		eq.droppedCount++
+	}
+	eq.queue = append(eq.queue, value)
+}

vendor/go.opentelemetry.io/otel/sdk/trace/id_generator.go

@@ -0,0 +1,77 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	crand "crypto/rand"
+	"encoding/binary"
+	"math/rand"
+	"sync"
+
+	"go.opentelemetry.io/otel/trace"
+)
+
+// IDGenerator allows custom generators for TraceID and SpanID.
+type IDGenerator interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// NewIDs returns a new trace and span ID.
+	NewIDs(ctx context.Context) (trace.TraceID, trace.SpanID)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// NewSpanID returns a ID for a new span in the trace with traceID.
+	NewSpanID(ctx context.Context, traceID trace.TraceID) trace.SpanID
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+type randomIDGenerator struct {
+	sync.Mutex
+	randSource *rand.Rand
+}
+
+var _ IDGenerator = &randomIDGenerator{}
+
+// NewSpanID returns a non-zero span ID from a randomly-chosen sequence.
+func (gen *randomIDGenerator) NewSpanID(ctx context.Context, traceID trace.TraceID) trace.SpanID {
+	gen.Lock()
+	defer gen.Unlock()
+	sid := trace.SpanID{}
+	gen.randSource.Read(sid[:])
+	return sid
+}
+
+// NewIDs returns a non-zero trace ID and a non-zero span ID from a
+// randomly-chosen sequence.
+func (gen *randomIDGenerator) NewIDs(ctx context.Context) (trace.TraceID, trace.SpanID) {
+	gen.Lock()
+	defer gen.Unlock()
+	tid := trace.TraceID{}
+	gen.randSource.Read(tid[:])
+	sid := trace.SpanID{}
+	gen.randSource.Read(sid[:])
+	return tid, sid
+}
+
+func defaultIDGenerator() IDGenerator {
+	gen := &randomIDGenerator{}
+	var rngSeed int64
+	_ = binary.Read(crand.Reader, binary.LittleEndian, &rngSeed)
+	gen.randSource = rand.New(rand.NewSource(rngSeed))
+	return gen
+}

vendor/go.opentelemetry.io/otel/sdk/trace/link.go

@@ -0,0 +1,34 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// Link is the relationship between two Spans. The relationship can be within
+// the same Trace or across different Traces.
+type Link struct {
+	// SpanContext of the linked Span.
+	SpanContext trace.SpanContext
+
+	// Attributes describe the aspects of the link.
+	Attributes []attribute.KeyValue
+
+	// DroppedAttributeCount is the number of attributes that were not
+	// recorded due to configured limits being reached.
+	DroppedAttributeCount int
+}

vendor/go.opentelemetry.io/otel/sdk/trace/provider.go

@@ -0,0 +1,450 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"sync/atomic"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/internal/global"
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/sdk/resource"
+	"go.opentelemetry.io/otel/trace"
+)
+
+const (
+	defaultTracerName = "go.opentelemetry.io/otel/sdk/tracer"
+)
+
+// tracerProviderConfig
+type tracerProviderConfig struct {
+	// processors contains collection of SpanProcessors that are processing pipeline
+	// for spans in the trace signal.
+	// SpanProcessors registered with a TracerProvider and are called at the start
+	// and end of a Span's lifecycle, and are called in the order they are
+	// registered.
+	processors []SpanProcessor
+
+	// sampler is the default sampler used when creating new spans.
+	sampler Sampler
+
+	// idGenerator is used to generate all Span and Trace IDs when needed.
+	idGenerator IDGenerator
+
+	// spanLimits defines the attribute, event, and link limits for spans.
+	spanLimits SpanLimits
+
+	// resource contains attributes representing an entity that produces telemetry.
+	resource *resource.Resource
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this exporter.
+func (cfg tracerProviderConfig) MarshalLog() interface{} {
+	return struct {
+		SpanProcessors  []SpanProcessor
+		SamplerType     string
+		IDGeneratorType string
+		SpanLimits      SpanLimits
+		Resource        *resource.Resource
+	}{
+		SpanProcessors:  cfg.processors,
+		SamplerType:     fmt.Sprintf("%T", cfg.sampler),
+		IDGeneratorType: fmt.Sprintf("%T", cfg.idGenerator),
+		SpanLimits:      cfg.spanLimits,
+		Resource:        cfg.resource,
+	}
+}
+
+type TracerProvider struct {
+	mu             sync.Mutex
+	namedTracer    map[instrumentation.Library]*tracer
+	spanProcessors atomic.Value
+
+	// These fields are not protected by the lock mu. They are assumed to be
+	// immutable after creation of the TracerProvider.
+	sampler     Sampler
+	idGenerator IDGenerator
+	spanLimits  SpanLimits
+	resource    *resource.Resource
+}
+
+var _ trace.TracerProvider = &TracerProvider{}
+
+// NewTracerProvider returns a new and configured TracerProvider.
+//
+// By default the returned TracerProvider is configured with:
+//  - a ParentBased(AlwaysSample) Sampler
+//  - a random number IDGenerator
+//  - the resource.Default() Resource
+//  - the default SpanLimits.
+//
+// The passed opts are used to override these default values and configure the
+// returned TracerProvider appropriately.
+func NewTracerProvider(opts ...TracerProviderOption) *TracerProvider {
+	o := tracerProviderConfig{
+		spanLimits: NewSpanLimits(),
+	}
+	o = applyTracerProviderEnvConfigs(o)
+
+	for _, opt := range opts {
+		o = opt.apply(o)
+	}
+
+	o = ensureValidTracerProviderConfig(o)
+
+	tp := &TracerProvider{
+		namedTracer: make(map[instrumentation.Library]*tracer),
+		sampler:     o.sampler,
+		idGenerator: o.idGenerator,
+		spanLimits:  o.spanLimits,
+		resource:    o.resource,
+	}
+
+	global.Info("TracerProvider created", "config", o)
+
+	for _, sp := range o.processors {
+		tp.RegisterSpanProcessor(sp)
+	}
+
+	return tp
+}
+
+// Tracer returns a Tracer with the given name and options. If a Tracer for
+// the given name and options does not exist it is created, otherwise the
+// existing Tracer is returned.
+//
+// If name is empty, DefaultTracerName is used instead.
+//
+// This method is safe to be called concurrently.
+func (p *TracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.Tracer {
+	c := trace.NewTracerConfig(opts...)
+
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if name == "" {
+		name = defaultTracerName
+	}
+	il := instrumentation.Library{
+		Name:      name,
+		Version:   c.InstrumentationVersion(),
+		SchemaURL: c.SchemaURL(),
+	}
+	t, ok := p.namedTracer[il]
+	if !ok {
+		t = &tracer{
+			provider:               p,
+			instrumentationLibrary: il,
+		}
+		p.namedTracer[il] = t
+		global.Info("Tracer created", "name", name, "version", c.InstrumentationVersion(), "schemaURL", c.SchemaURL())
+	}
+	return t
+}
+
+// RegisterSpanProcessor adds the given SpanProcessor to the list of SpanProcessors
+func (p *TracerProvider) RegisterSpanProcessor(s SpanProcessor) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	new := spanProcessorStates{}
+	if old, ok := p.spanProcessors.Load().(spanProcessorStates); ok {
+		new = append(new, old...)
+	}
+	newSpanSync := &spanProcessorState{
+		sp:    s,
+		state: &sync.Once{},
+	}
+	new = append(new, newSpanSync)
+	p.spanProcessors.Store(new)
+}
+
+// UnregisterSpanProcessor removes the given SpanProcessor from the list of SpanProcessors
+func (p *TracerProvider) UnregisterSpanProcessor(s SpanProcessor) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	spss := spanProcessorStates{}
+	old, ok := p.spanProcessors.Load().(spanProcessorStates)
+	if !ok || len(old) == 0 {
+		return
+	}
+	spss = append(spss, old...)
+
+	// stop the span processor if it is started and remove it from the list
+	var stopOnce *spanProcessorState
+	var idx int
+	for i, sps := range spss {
+		if sps.sp == s {
+			stopOnce = sps
+			idx = i
+		}
+	}
+	if stopOnce != nil {
+		stopOnce.state.Do(func() {
+			if err := s.Shutdown(context.Background()); err != nil {
+				otel.Handle(err)
+			}
+		})
+	}
+	if len(spss) > 1 {
+		copy(spss[idx:], spss[idx+1:])
+	}
+	spss[len(spss)-1] = nil
+	spss = spss[:len(spss)-1]
+
+	p.spanProcessors.Store(spss)
+}
+
+// ForceFlush immediately exports all spans that have not yet been exported for
+// all the registered span processors.
+func (p *TracerProvider) ForceFlush(ctx context.Context) error {
+	spss, ok := p.spanProcessors.Load().(spanProcessorStates)
+	if !ok {
+		return fmt.Errorf("failed to load span processors")
+	}
+	if len(spss) == 0 {
+		return nil
+	}
+
+	for _, sps := range spss {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+		}
+
+		if err := sps.sp.ForceFlush(ctx); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Shutdown shuts down the span processors in the order they were registered.
+func (p *TracerProvider) Shutdown(ctx context.Context) error {
+	spss, ok := p.spanProcessors.Load().(spanProcessorStates)
+	if !ok {
+		return fmt.Errorf("failed to load span processors")
+	}
+	if len(spss) == 0 {
+		return nil
+	}
+
+	for _, sps := range spss {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+		}
+
+		var err error
+		sps.state.Do(func() {
+			err = sps.sp.Shutdown(ctx)
+		})
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+type TracerProviderOption interface {
+	apply(tracerProviderConfig) tracerProviderConfig
+}
+
+type traceProviderOptionFunc func(tracerProviderConfig) tracerProviderConfig
+
+func (fn traceProviderOptionFunc) apply(cfg tracerProviderConfig) tracerProviderConfig {
+	return fn(cfg)
+}
+
+// WithSyncer registers the exporter with the TracerProvider using a
+// SimpleSpanProcessor.
+//
+// This is not recommended for production use. The synchronous nature of the
+// SimpleSpanProcessor that will wrap the exporter make it good for testing,
+// debugging, or showing examples of other feature, but it will be slow and
+// have a high computation resource usage overhead. The WithBatcher option is
+// recommended for production use instead.
+func WithSyncer(e SpanExporter) TracerProviderOption {
+	return WithSpanProcessor(NewSimpleSpanProcessor(e))
+}
+
+// WithBatcher registers the exporter with the TracerProvider using a
+// BatchSpanProcessor configured with the passed opts.
+func WithBatcher(e SpanExporter, opts ...BatchSpanProcessorOption) TracerProviderOption {
+	return WithSpanProcessor(NewBatchSpanProcessor(e, opts...))
+}
+
+// WithSpanProcessor registers the SpanProcessor with a TracerProvider.
+func WithSpanProcessor(sp SpanProcessor) TracerProviderOption {
+	return traceProviderOptionFunc(func(cfg tracerProviderConfig) tracerProviderConfig {
+		cfg.processors = append(cfg.processors, sp)
+		return cfg
+	})
+}
+
+// WithResource returns a TracerProviderOption that will configure the
+// Resource r as a TracerProvider's Resource. The configured Resource is
+// referenced by all the Tracers the TracerProvider creates. It represents the
+// entity producing telemetry.
+//
+// If this option is not used, the TracerProvider will use the
+// resource.Default() Resource by default.
+func WithResource(r *resource.Resource) TracerProviderOption {
+	return traceProviderOptionFunc(func(cfg tracerProviderConfig) tracerProviderConfig {
+		var err error
+		cfg.resource, err = resource.Merge(resource.Environment(), r)
+		if err != nil {
+			otel.Handle(err)
+		}
+		return cfg
+	})
+}
+
+// WithIDGenerator returns a TracerProviderOption that will configure the
+// IDGenerator g as a TracerProvider's IDGenerator. The configured IDGenerator
+// is used by the Tracers the TracerProvider creates to generate new Span and
+// Trace IDs.
+//
+// If this option is not used, the TracerProvider will use a random number
+// IDGenerator by default.
+func WithIDGenerator(g IDGenerator) TracerProviderOption {
+	return traceProviderOptionFunc(func(cfg tracerProviderConfig) tracerProviderConfig {
+		if g != nil {
+			cfg.idGenerator = g
+		}
+		return cfg
+	})
+}
+
+// WithSampler returns a TracerProviderOption that will configure the Sampler
+// s as a TracerProvider's Sampler. The configured Sampler is used by the
+// Tracers the TracerProvider creates to make their sampling decisions for the
+// Spans they create.
+//
+// This option overrides the Sampler configured through the OTEL_TRACES_SAMPLER
+// and OTEL_TRACES_SAMPLER_ARG environment variables. If this option is not used
+// and the sampler is not configured through environment variables or the environment
+// contains invalid/unsupported configuration, the TracerProvider will use a
+// ParentBased(AlwaysSample) Sampler by default.
+func WithSampler(s Sampler) TracerProviderOption {
+	return traceProviderOptionFunc(func(cfg tracerProviderConfig) tracerProviderConfig {
+		if s != nil {
+			cfg.sampler = s
+		}
+		return cfg
+	})
+}
+
+// WithSpanLimits returns a TracerProviderOption that configures a
+// TracerProvider to use the SpanLimits sl. These SpanLimits bound any Span
+// created by a Tracer from the TracerProvider.
+//
+// If any field of sl is zero or negative it will be replaced with the default
+// value for that field.
+//
+// If this or WithRawSpanLimits are not provided, the TracerProvider will use
+// the limits defined by environment variables, or the defaults if unset.
+// Refer to the NewSpanLimits documentation for information about this
+// relationship.
+//
+// Deprecated: Use WithRawSpanLimits instead which allows setting unlimited
+// and zero limits. This option will be kept until the next major version
+// incremented release.
+func WithSpanLimits(sl SpanLimits) TracerProviderOption {
+	if sl.AttributeValueLengthLimit <= 0 {
+		sl.AttributeValueLengthLimit = DefaultAttributeValueLengthLimit
+	}
+	if sl.AttributeCountLimit <= 0 {
+		sl.AttributeCountLimit = DefaultAttributeCountLimit
+	}
+	if sl.EventCountLimit <= 0 {
+		sl.EventCountLimit = DefaultEventCountLimit
+	}
+	if sl.AttributePerEventCountLimit <= 0 {
+		sl.AttributePerEventCountLimit = DefaultAttributePerEventCountLimit
+	}
+	if sl.LinkCountLimit <= 0 {
+		sl.LinkCountLimit = DefaultLinkCountLimit
+	}
+	if sl.AttributePerLinkCountLimit <= 0 {
+		sl.AttributePerLinkCountLimit = DefaultAttributePerLinkCountLimit
+	}
+	return traceProviderOptionFunc(func(cfg tracerProviderConfig) tracerProviderConfig {
+		cfg.spanLimits = sl
+		return cfg
+	})
+}
+
+// WithRawSpanLimits returns a TracerProviderOption that configures a
+// TracerProvider to use these limits. These limits bound any Span created by
+// a Tracer from the TracerProvider.
+//
+// The limits will be used as-is. Zero or negative values will not be changed
+// to the default value like WithSpanLimits does. Setting a limit to zero will
+// effectively disable the related resource it limits and setting to a
+// negative value will mean that resource is unlimited. Consequentially, this
+// means that the zero-value SpanLimits will disable all span resources.
+// Because of this, limits should be constructed using NewSpanLimits and
+// updated accordingly.
+//
+// If this or WithSpanLimits are not provided, the TracerProvider will use the
+// limits defined by environment variables, or the defaults if unset. Refer to
+// the NewSpanLimits documentation for information about this relationship.
+func WithRawSpanLimits(limits SpanLimits) TracerProviderOption {
+	return traceProviderOptionFunc(func(cfg tracerProviderConfig) tracerProviderConfig {
+		cfg.spanLimits = limits
+		return cfg
+	})
+}
+
+func applyTracerProviderEnvConfigs(cfg tracerProviderConfig) tracerProviderConfig {
+	for _, opt := range tracerProviderOptionsFromEnv() {
+		cfg = opt.apply(cfg)
+	}
+
+	return cfg
+}
+
+func tracerProviderOptionsFromEnv() []TracerProviderOption {
+	var opts []TracerProviderOption
+
+	sampler, err := samplerFromEnv()
+	if err != nil {
+		otel.Handle(err)
+	}
+
+	if sampler != nil {
+		opts = append(opts, WithSampler(sampler))
+	}
+
+	return opts
+}
+
+// ensureValidTracerProviderConfig ensures that given TracerProviderConfig is valid.
+func ensureValidTracerProviderConfig(cfg tracerProviderConfig) tracerProviderConfig {
+	if cfg.sampler == nil {
+		cfg.sampler = ParentBased(AlwaysSample())
+	}
+	if cfg.idGenerator == nil {
+		cfg.idGenerator = defaultIDGenerator()
+	}
+	if cfg.resource == nil {
+		cfg.resource = resource.Default()
+	}
+	return cfg
+}

vendor/go.opentelemetry.io/otel/sdk/trace/sampler_env.go

@@ -0,0 +1,107 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+const (
+	tracesSamplerKey    = "OTEL_TRACES_SAMPLER"
+	tracesSamplerArgKey = "OTEL_TRACES_SAMPLER_ARG"
+
+	samplerAlwaysOn                = "always_on"
+	samplerAlwaysOff               = "always_off"
+	samplerTraceIDRatio            = "traceidratio"
+	samplerParentBasedAlwaysOn     = "parentbased_always_on"
+	samplerParsedBasedAlwaysOff    = "parentbased_always_off"
+	samplerParentBasedTraceIDRatio = "parentbased_traceidratio"
+)
+
+type errUnsupportedSampler string
+
+func (e errUnsupportedSampler) Error() string {
+	return fmt.Sprintf("unsupported sampler: %s", string(e))
+}
+
+var (
+	errNegativeTraceIDRatio       = errors.New("invalid trace ID ratio: less than 0.0")
+	errGreaterThanOneTraceIDRatio = errors.New("invalid trace ID ratio: greater than 1.0")
+)
+
+type samplerArgParseError struct {
+	parseErr error
+}
+
+func (e samplerArgParseError) Error() string {
+	return fmt.Sprintf("parsing sampler argument: %s", e.parseErr.Error())
+}
+
+func (e samplerArgParseError) Unwrap() error {
+	return e.parseErr
+}
+
+func samplerFromEnv() (Sampler, error) {
+	sampler, ok := os.LookupEnv(tracesSamplerKey)
+	if !ok {
+		return nil, nil
+	}
+
+	sampler = strings.ToLower(strings.TrimSpace(sampler))
+	samplerArg, hasSamplerArg := os.LookupEnv(tracesSamplerArgKey)
+	samplerArg = strings.TrimSpace(samplerArg)
+
+	switch sampler {
+	case samplerAlwaysOn:
+		return AlwaysSample(), nil
+	case samplerAlwaysOff:
+		return NeverSample(), nil
+	case samplerTraceIDRatio:
+		ratio, err := parseTraceIDRatio(samplerArg, hasSamplerArg)
+		return ratio, err
+	case samplerParentBasedAlwaysOn:
+		return ParentBased(AlwaysSample()), nil
+	case samplerParsedBasedAlwaysOff:
+		return ParentBased(NeverSample()), nil
+	case samplerParentBasedTraceIDRatio:
+		ratio, err := parseTraceIDRatio(samplerArg, hasSamplerArg)
+		return ParentBased(ratio), err
+	default:
+		return nil, errUnsupportedSampler(sampler)
+	}
+
+}
+
+func parseTraceIDRatio(arg string, hasSamplerArg bool) (Sampler, error) {
+	if !hasSamplerArg {
+		return TraceIDRatioBased(1.0), nil
+	}
+	v, err := strconv.ParseFloat(arg, 64)
+	if err != nil {
+		return TraceIDRatioBased(1.0), samplerArgParseError{err}
+	}
+	if v < 0.0 {
+		return TraceIDRatioBased(1.0), errNegativeTraceIDRatio
+	}
+	if v > 1.0 {
+		return TraceIDRatioBased(1.0), errGreaterThanOneTraceIDRatio
+	}
+
+	return TraceIDRatioBased(v), nil
+}

vendor/go.opentelemetry.io/otel/sdk/trace/sampling.go

@@ -0,0 +1,292 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"encoding/binary"
+	"fmt"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// Sampler decides whether a trace should be sampled and exported.
+type Sampler interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// ShouldSample returns a SamplingResult based on a decision made from the
+	// passed parameters.
+	ShouldSample(parameters SamplingParameters) SamplingResult
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Description returns information describing the Sampler.
+	Description() string
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+// SamplingParameters contains the values passed to a Sampler.
+type SamplingParameters struct {
+	ParentContext context.Context
+	TraceID       trace.TraceID
+	Name          string
+	Kind          trace.SpanKind
+	Attributes    []attribute.KeyValue
+	Links         []trace.Link
+}
+
+// SamplingDecision indicates whether a span is dropped, recorded and/or sampled.
+type SamplingDecision uint8
+
+// Valid sampling decisions
+const (
+	// Drop will not record the span and all attributes/events will be dropped
+	Drop SamplingDecision = iota
+
+	// Record indicates the span's `IsRecording() == true`, but `Sampled` flag
+	// *must not* be set
+	RecordOnly
+
+	// RecordAndSample has span's `IsRecording() == true` and `Sampled` flag
+	// *must* be set
+	RecordAndSample
+)
+
+// SamplingResult conveys a SamplingDecision, set of Attributes and a Tracestate.
+type SamplingResult struct {
+	Decision   SamplingDecision
+	Attributes []attribute.KeyValue
+	Tracestate trace.TraceState
+}
+
+type traceIDRatioSampler struct {
+	traceIDUpperBound uint64
+	description       string
+}
+
+func (ts traceIDRatioSampler) ShouldSample(p SamplingParameters) SamplingResult {
+	psc := trace.SpanContextFromContext(p.ParentContext)
+	x := binary.BigEndian.Uint64(p.TraceID[0:8]) >> 1
+	if x < ts.traceIDUpperBound {
+		return SamplingResult{
+			Decision:   RecordAndSample,
+			Tracestate: psc.TraceState(),
+		}
+	}
+	return SamplingResult{
+		Decision:   Drop,
+		Tracestate: psc.TraceState(),
+	}
+}
+
+func (ts traceIDRatioSampler) Description() string {
+	return ts.description
+}
+
+// TraceIDRatioBased samples a given fraction of traces. Fractions >= 1 will
+// always sample. Fractions < 0 are treated as zero. To respect the
+// parent trace's `SampledFlag`, the `TraceIDRatioBased` sampler should be used
+// as a delegate of a `Parent` sampler.
+//nolint:revive // revive complains about stutter of `trace.TraceIDRatioBased`
+func TraceIDRatioBased(fraction float64) Sampler {
+	if fraction >= 1 {
+		return AlwaysSample()
+	}
+
+	if fraction <= 0 {
+		fraction = 0
+	}
+
+	return &traceIDRatioSampler{
+		traceIDUpperBound: uint64(fraction * (1 << 63)),
+		description:       fmt.Sprintf("TraceIDRatioBased{%g}", fraction),
+	}
+}
+
+type alwaysOnSampler struct{}
+
+func (as alwaysOnSampler) ShouldSample(p SamplingParameters) SamplingResult {
+	return SamplingResult{
+		Decision:   RecordAndSample,
+		Tracestate: trace.SpanContextFromContext(p.ParentContext).TraceState(),
+	}
+}
+
+func (as alwaysOnSampler) Description() string {
+	return "AlwaysOnSampler"
+}
+
+// AlwaysSample returns a Sampler that samples every trace.
+// Be careful about using this sampler in a production application with
+// significant traffic: a new trace will be started and exported for every
+// request.
+func AlwaysSample() Sampler {
+	return alwaysOnSampler{}
+}
+
+type alwaysOffSampler struct{}
+
+func (as alwaysOffSampler) ShouldSample(p SamplingParameters) SamplingResult {
+	return SamplingResult{
+		Decision:   Drop,
+		Tracestate: trace.SpanContextFromContext(p.ParentContext).TraceState(),
+	}
+}
+
+func (as alwaysOffSampler) Description() string {
+	return "AlwaysOffSampler"
+}
+
+// NeverSample returns a Sampler that samples no traces.
+func NeverSample() Sampler {
+	return alwaysOffSampler{}
+}
+
+// ParentBased returns a composite sampler which behaves differently,
+// based on the parent of the span. If the span has no parent,
+// the root(Sampler) is used to make sampling decision. If the span has
+// a parent, depending on whether the parent is remote and whether it
+// is sampled, one of the following samplers will apply:
+// - remoteParentSampled(Sampler) (default: AlwaysOn)
+// - remoteParentNotSampled(Sampler) (default: AlwaysOff)
+// - localParentSampled(Sampler) (default: AlwaysOn)
+// - localParentNotSampled(Sampler) (default: AlwaysOff)
+func ParentBased(root Sampler, samplers ...ParentBasedSamplerOption) Sampler {
+	return parentBased{
+		root:   root,
+		config: configureSamplersForParentBased(samplers),
+	}
+}
+
+type parentBased struct {
+	root   Sampler
+	config samplerConfig
+}
+
+func configureSamplersForParentBased(samplers []ParentBasedSamplerOption) samplerConfig {
+	c := samplerConfig{
+		remoteParentSampled:    AlwaysSample(),
+		remoteParentNotSampled: NeverSample(),
+		localParentSampled:     AlwaysSample(),
+		localParentNotSampled:  NeverSample(),
+	}
+
+	for _, so := range samplers {
+		c = so.apply(c)
+	}
+
+	return c
+}
+
+// samplerConfig is a group of options for parentBased sampler.
+type samplerConfig struct {
+	remoteParentSampled, remoteParentNotSampled Sampler
+	localParentSampled, localParentNotSampled   Sampler
+}
+
+// ParentBasedSamplerOption configures the sampler for a particular sampling case.
+type ParentBasedSamplerOption interface {
+	apply(samplerConfig) samplerConfig
+}
+
+// WithRemoteParentSampled sets the sampler for the case of sampled remote parent.
+func WithRemoteParentSampled(s Sampler) ParentBasedSamplerOption {
+	return remoteParentSampledOption{s}
+}
+
+type remoteParentSampledOption struct {
+	s Sampler
+}
+
+func (o remoteParentSampledOption) apply(config samplerConfig) samplerConfig {
+	config.remoteParentSampled = o.s
+	return config
+}
+
+// WithRemoteParentNotSampled sets the sampler for the case of remote parent
+// which is not sampled.
+func WithRemoteParentNotSampled(s Sampler) ParentBasedSamplerOption {
+	return remoteParentNotSampledOption{s}
+}
+
+type remoteParentNotSampledOption struct {
+	s Sampler
+}
+
+func (o remoteParentNotSampledOption) apply(config samplerConfig) samplerConfig {
+	config.remoteParentNotSampled = o.s
+	return config
+}
+
+// WithLocalParentSampled sets the sampler for the case of sampled local parent.
+func WithLocalParentSampled(s Sampler) ParentBasedSamplerOption {
+	return localParentSampledOption{s}
+}
+
+type localParentSampledOption struct {
+	s Sampler
+}
+
+func (o localParentSampledOption) apply(config samplerConfig) samplerConfig {
+	config.localParentSampled = o.s
+	return config
+}
+
+// WithLocalParentNotSampled sets the sampler for the case of local parent
+// which is not sampled.
+func WithLocalParentNotSampled(s Sampler) ParentBasedSamplerOption {
+	return localParentNotSampledOption{s}
+}
+
+type localParentNotSampledOption struct {
+	s Sampler
+}
+
+func (o localParentNotSampledOption) apply(config samplerConfig) samplerConfig {
+	config.localParentNotSampled = o.s
+	return config
+}
+
+func (pb parentBased) ShouldSample(p SamplingParameters) SamplingResult {
+	psc := trace.SpanContextFromContext(p.ParentContext)
+	if psc.IsValid() {
+		if psc.IsRemote() {
+			if psc.IsSampled() {
+				return pb.config.remoteParentSampled.ShouldSample(p)
+			}
+			return pb.config.remoteParentNotSampled.ShouldSample(p)
+		}
+
+		if psc.IsSampled() {
+			return pb.config.localParentSampled.ShouldSample(p)
+		}
+		return pb.config.localParentNotSampled.ShouldSample(p)
+	}
+	return pb.root.ShouldSample(p)
+}
+
+func (pb parentBased) Description() string {
+	return fmt.Sprintf("ParentBased{root:%s,remoteParentSampled:%s,"+
+		"remoteParentNotSampled:%s,localParentSampled:%s,localParentNotSampled:%s}",
+		pb.root.Description(),
+		pb.config.remoteParentSampled.Description(),
+		pb.config.remoteParentNotSampled.Description(),
+		pb.config.localParentSampled.Description(),
+		pb.config.localParentNotSampled.Description(),
+	)
+}

vendor/go.opentelemetry.io/otel/sdk/trace/simple_span_processor.go

@@ -0,0 +1,128 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"sync"
+
+	"go.opentelemetry.io/otel"
+)
+
+// simpleSpanProcessor is a SpanProcessor that synchronously sends all
+// completed Spans to a trace.Exporter immediately.
+type simpleSpanProcessor struct {
+	exporterMu sync.RWMutex
+	exporter   SpanExporter
+	stopOnce   sync.Once
+}
+
+var _ SpanProcessor = (*simpleSpanProcessor)(nil)
+
+// NewSimpleSpanProcessor returns a new SpanProcessor that will synchronously
+// send completed spans to the exporter immediately.
+//
+// This SpanProcessor is not recommended for production use. The synchronous
+// nature of this SpanProcessor make it good for testing, debugging, or
+// showing examples of other feature, but it will be slow and have a high
+// computation resource usage overhead. The BatchSpanProcessor is recommended
+// for production use instead.
+func NewSimpleSpanProcessor(exporter SpanExporter) SpanProcessor {
+	ssp := &simpleSpanProcessor{
+		exporter: exporter,
+	}
+	return ssp
+}
+
+// OnStart does nothing.
+func (ssp *simpleSpanProcessor) OnStart(context.Context, ReadWriteSpan) {}
+
+// OnEnd immediately exports a ReadOnlySpan.
+func (ssp *simpleSpanProcessor) OnEnd(s ReadOnlySpan) {
+	ssp.exporterMu.RLock()
+	defer ssp.exporterMu.RUnlock()
+
+	if ssp.exporter != nil && s.SpanContext().TraceFlags().IsSampled() {
+		if err := ssp.exporter.ExportSpans(context.Background(), []ReadOnlySpan{s}); err != nil {
+			otel.Handle(err)
+		}
+	}
+}
+
+// Shutdown shuts down the exporter this SimpleSpanProcessor exports to.
+func (ssp *simpleSpanProcessor) Shutdown(ctx context.Context) error {
+	var err error
+	ssp.stopOnce.Do(func() {
+		stopFunc := func(exp SpanExporter) (<-chan error, func()) {
+			done := make(chan error)
+			return done, func() { done <- exp.Shutdown(ctx) }
+		}
+
+		// The exporter field of the simpleSpanProcessor needs to be zeroed to
+		// signal it is shut down, meaning all subsequent calls to OnEnd will
+		// be gracefully ignored. This needs to be done synchronously to avoid
+		// any race condition.
+		//
+		// A closure is used to keep reference to the exporter and then the
+		// field is zeroed. This ensures the simpleSpanProcessor is shut down
+		// before the exporter. This order is important as it avoids a
+		// potential deadlock. If the exporter shut down operation generates a
+		// span, that span would need to be exported. Meaning, OnEnd would be
+		// called and try acquiring the lock that is held here.
+		ssp.exporterMu.Lock()
+		done, shutdown := stopFunc(ssp.exporter)
+		ssp.exporter = nil
+		ssp.exporterMu.Unlock()
+
+		go shutdown()
+
+		// Wait for the exporter to shut down or the deadline to expire.
+		select {
+		case err = <-done:
+		case <-ctx.Done():
+			// It is possible for the exporter to have immediately shut down
+			// and the context to be done simultaneously. In that case this
+			// outer select statement will randomly choose a case. This will
+			// result in a different returned error for similar scenarios.
+			// Instead, double check if the exporter shut down at the same
+			// time and return that error if so. This will ensure consistency
+			// as well as ensure the caller knows the exporter shut down
+			// successfully (they can already determine if the deadline is
+			// expired given they passed the context).
+			select {
+			case err = <-done:
+			default:
+				err = ctx.Err()
+			}
+		}
+	})
+	return err
+}
+
+// ForceFlush does nothing as there is no data to flush.
+func (ssp *simpleSpanProcessor) ForceFlush(context.Context) error {
+	return nil
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this Span Processor.
+func (ssp *simpleSpanProcessor) MarshalLog() interface{} {
+	return struct {
+		Type     string
+		Exporter SpanExporter
+	}{
+		Type:     "SimpleSpanProcessor",
+		Exporter: ssp.exporter,
+	}
+}

vendor/go.opentelemetry.io/otel/sdk/trace/snapshot.go

@@ -0,0 +1,138 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"time"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/sdk/resource"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// snapshot is an record of a spans state at a particular checkpointed time.
+// It is used as a read-only representation of that state.
+type snapshot struct {
+	name                   string
+	spanContext            trace.SpanContext
+	parent                 trace.SpanContext
+	spanKind               trace.SpanKind
+	startTime              time.Time
+	endTime                time.Time
+	attributes             []attribute.KeyValue
+	events                 []Event
+	links                  []Link
+	status                 Status
+	childSpanCount         int
+	droppedAttributeCount  int
+	droppedEventCount      int
+	droppedLinkCount       int
+	resource               *resource.Resource
+	instrumentationLibrary instrumentation.Library
+}
+
+var _ ReadOnlySpan = snapshot{}
+
+func (s snapshot) private() {}
+
+// Name returns the name of the span.
+func (s snapshot) Name() string {
+	return s.name
+}
+
+// SpanContext returns the unique SpanContext that identifies the span.
+func (s snapshot) SpanContext() trace.SpanContext {
+	return s.spanContext
+}
+
+// Parent returns the unique SpanContext that identifies the parent of the
+// span if one exists. If the span has no parent the returned SpanContext
+// will be invalid.
+func (s snapshot) Parent() trace.SpanContext {
+	return s.parent
+}
+
+// SpanKind returns the role the span plays in a Trace.
+func (s snapshot) SpanKind() trace.SpanKind {
+	return s.spanKind
+}
+
+// StartTime returns the time the span started recording.
+func (s snapshot) StartTime() time.Time {
+	return s.startTime
+}
+
+// EndTime returns the time the span stopped recording. It will be zero if
+// the span has not ended.
+func (s snapshot) EndTime() time.Time {
+	return s.endTime
+}
+
+// Attributes returns the defining attributes of the span.
+func (s snapshot) Attributes() []attribute.KeyValue {
+	return s.attributes
+}
+
+// Links returns all the links the span has to other spans.
+func (s snapshot) Links() []Link {
+	return s.links
+}
+
+// Events returns all the events that occurred within in the spans
+// lifetime.
+func (s snapshot) Events() []Event {
+	return s.events
+}
+
+// Status returns the spans status.
+func (s snapshot) Status() Status {
+	return s.status
+}
+
+// InstrumentationLibrary returns information about the instrumentation
+// library that created the span.
+func (s snapshot) InstrumentationLibrary() instrumentation.Library {
+	return s.instrumentationLibrary
+}
+
+// Resource returns information about the entity that produced the span.
+func (s snapshot) Resource() *resource.Resource {
+	return s.resource
+}
+
+// DroppedAttributes returns the number of attributes dropped by the span
+// due to limits being reached.
+func (s snapshot) DroppedAttributes() int {
+	return s.droppedAttributeCount
+}
+
+// DroppedLinks returns the number of links dropped by the span due to limits
+// being reached.
+func (s snapshot) DroppedLinks() int {
+	return s.droppedLinkCount
+}
+
+// DroppedEvents returns the number of events dropped by the span due to
+// limits being reached.
+func (s snapshot) DroppedEvents() int {
+	return s.droppedEventCount
+}
+
+// ChildSpanCount returns the count of spans that consider the span a
+// direct parent.
+func (s snapshot) ChildSpanCount() int {
+	return s.childSpanCount
+}

vendor/go.opentelemetry.io/otel/sdk/trace/span.go

@@ -0,0 +1,797 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"runtime"
+	rt "runtime/trace"
+	"sync"
+	"time"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/sdk/internal"
+	"go.opentelemetry.io/otel/sdk/resource"
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// ReadOnlySpan allows reading information from the data structure underlying a
+// trace.Span. It is used in places where reading information from a span is
+// necessary but changing the span isn't necessary or allowed.
+//
+// Warning: methods may be added to this interface in minor releases.
+type ReadOnlySpan interface {
+	// Name returns the name of the span.
+	Name() string
+	// SpanContext returns the unique SpanContext that identifies the span.
+	SpanContext() trace.SpanContext
+	// Parent returns the unique SpanContext that identifies the parent of the
+	// span if one exists. If the span has no parent the returned SpanContext
+	// will be invalid.
+	Parent() trace.SpanContext
+	// SpanKind returns the role the span plays in a Trace.
+	SpanKind() trace.SpanKind
+	// StartTime returns the time the span started recording.
+	StartTime() time.Time
+	// EndTime returns the time the span stopped recording. It will be zero if
+	// the span has not ended.
+	EndTime() time.Time
+	// Attributes returns the defining attributes of the span.
+	// The order of the returned attributes is not guaranteed to be stable across invocations.
+	Attributes() []attribute.KeyValue
+	// Links returns all the links the span has to other spans.
+	Links() []Link
+	// Events returns all the events that occurred within in the spans
+	// lifetime.
+	Events() []Event
+	// Status returns the spans status.
+	Status() Status
+	// InstrumentationLibrary returns information about the instrumentation
+	// library that created the span.
+	InstrumentationLibrary() instrumentation.Library
+	// Resource returns information about the entity that produced the span.
+	Resource() *resource.Resource
+	// DroppedAttributes returns the number of attributes dropped by the span
+	// due to limits being reached.
+	DroppedAttributes() int
+	// DroppedLinks returns the number of links dropped by the span due to
+	// limits being reached.
+	DroppedLinks() int
+	// DroppedEvents returns the number of events dropped by the span due to
+	// limits being reached.
+	DroppedEvents() int
+	// ChildSpanCount returns the count of spans that consider the span a
+	// direct parent.
+	ChildSpanCount() int
+
+	// A private method to prevent users implementing the
+	// interface and so future additions to it will not
+	// violate compatibility.
+	private()
+}
+
+// ReadWriteSpan exposes the same methods as trace.Span and in addition allows
+// reading information from the underlying data structure.
+// This interface exposes the union of the methods of trace.Span (which is a
+// "write-only" span) and ReadOnlySpan. New methods for writing or reading span
+// information should be added under trace.Span or ReadOnlySpan, respectively.
+//
+// Warning: methods may be added to this interface in minor releases.
+type ReadWriteSpan interface {
+	trace.Span
+	ReadOnlySpan
+}
+
+// recordingSpan is an implementation of the OpenTelemetry Span API
+// representing the individual component of a trace that is sampled.
+type recordingSpan struct {
+	// mu protects the contents of this span.
+	mu sync.Mutex
+
+	// parent holds the parent span of this span as a trace.SpanContext.
+	parent trace.SpanContext
+
+	// spanKind represents the kind of this span as a trace.SpanKind.
+	spanKind trace.SpanKind
+
+	// name is the name of this span.
+	name string
+
+	// startTime is the time at which this span was started.
+	startTime time.Time
+
+	// endTime is the time at which this span was ended. It contains the zero
+	// value of time.Time until the span is ended.
+	endTime time.Time
+
+	// status is the status of this span.
+	status Status
+
+	// childSpanCount holds the number of child spans created for this span.
+	childSpanCount int
+
+	// spanContext holds the SpanContext of this span.
+	spanContext trace.SpanContext
+
+	// attributes is a collection of user provided key/values. The collection
+	// is constrained by a configurable maximum held by the parent
+	// TracerProvider. When additional attributes are added after this maximum
+	// is reached these attributes the user is attempting to add are dropped.
+	// This dropped number of attributes is tracked and reported in the
+	// ReadOnlySpan exported when the span ends.
+	attributes        []attribute.KeyValue
+	droppedAttributes int
+
+	// events are stored in FIFO queue capped by configured limit.
+	events evictedQueue
+
+	// links are stored in FIFO queue capped by configured limit.
+	links evictedQueue
+
+	// executionTracerTaskEnd ends the execution tracer span.
+	executionTracerTaskEnd func()
+
+	// tracer is the SDK tracer that created this span.
+	tracer *tracer
+}
+
+var _ ReadWriteSpan = (*recordingSpan)(nil)
+var _ runtimeTracer = (*recordingSpan)(nil)
+
+// SpanContext returns the SpanContext of this span.
+func (s *recordingSpan) SpanContext() trace.SpanContext {
+	if s == nil {
+		return trace.SpanContext{}
+	}
+	return s.spanContext
+}
+
+// IsRecording returns if this span is being recorded. If this span has ended
+// this will return false.
+func (s *recordingSpan) IsRecording() bool {
+	if s == nil {
+		return false
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	return s.endTime.IsZero()
+}
+
+// SetStatus sets the status of the Span in the form of a code and a
+// description, overriding previous values set. The description is only
+// included in the set status when the code is for an error. If this span is
+// not being recorded than this method does nothing.
+func (s *recordingSpan) SetStatus(code codes.Code, description string) {
+	if !s.IsRecording() {
+		return
+	}
+
+	status := Status{Code: code}
+	if code == codes.Error {
+		status.Description = description
+	}
+
+	s.mu.Lock()
+	s.status = status
+	s.mu.Unlock()
+}
+
+// SetAttributes sets attributes of this span.
+//
+// If a key from attributes already exists the value associated with that key
+// will be overwritten with the value contained in attributes.
+//
+// If this span is not being recorded than this method does nothing.
+//
+// If adding attributes to the span would exceed the maximum amount of
+// attributes the span is configured to have, the last added attributes will
+// be dropped.
+func (s *recordingSpan) SetAttributes(attributes ...attribute.KeyValue) {
+	if !s.IsRecording() {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	limit := s.tracer.provider.spanLimits.AttributeCountLimit
+	if limit == 0 {
+		// No attributes allowed.
+		s.droppedAttributes += len(attributes)
+		return
+	}
+
+	// If adding these attributes could exceed the capacity of s perform a
+	// de-duplication and truncation while adding to avoid over allocation.
+	if limit > 0 && len(s.attributes)+len(attributes) > limit {
+		s.addOverCapAttrs(limit, attributes)
+		return
+	}
+
+	// Otherwise, add without deduplication. When attributes are read they
+	// will be deduplicated, optimizing the operation.
+	for _, a := range attributes {
+		if !a.Valid() {
+			// Drop all invalid attributes.
+			s.droppedAttributes++
+			continue
+		}
+		a = truncateAttr(s.tracer.provider.spanLimits.AttributeValueLengthLimit, a)
+		s.attributes = append(s.attributes, a)
+	}
+}
+
+// addOverCapAttrs adds the attributes attrs to the span s while
+// de-duplicating the attributes of s and attrs and dropping attributes that
+// exceed the limit.
+//
+// This method assumes s.mu.Lock is held by the caller.
+//
+// This method should only be called when there is a possibility that adding
+// attrs to s will exceed the limit. Otherwise, attrs should be added to s
+// without checking for duplicates and all retrieval methods of the attributes
+// for s will de-duplicate as needed.
+//
+// This method assumes limit is a value > 0. The argument should be validated
+// by the caller.
+func (s *recordingSpan) addOverCapAttrs(limit int, attrs []attribute.KeyValue) {
+	// In order to not allocate more capacity to s.attributes than needed,
+	// prune and truncate this addition of attributes while adding.
+
+	// Do not set a capacity when creating this map. Benchmark testing has
+	// showed this to only add unused memory allocations in general use.
+	exists := make(map[attribute.Key]int)
+	s.dedupeAttrsFromRecord(&exists)
+
+	// Now that s.attributes is deduplicated, adding unique attributes up to
+	// the capacity of s will not over allocate s.attributes.
+	for _, a := range attrs {
+		if !a.Valid() {
+			// Drop all invalid attributes.
+			s.droppedAttributes++
+			continue
+		}
+
+		if idx, ok := exists[a.Key]; ok {
+			// Perform all updates before dropping, even when at capacity.
+			s.attributes[idx] = a
+			continue
+		}
+
+		if len(s.attributes) >= limit {
+			// Do not just drop all of the remaining attributes, make sure
+			// updates are checked and performed.
+			s.droppedAttributes++
+		} else {
+			a = truncateAttr(s.tracer.provider.spanLimits.AttributeValueLengthLimit, a)
+			s.attributes = append(s.attributes, a)
+			exists[a.Key] = len(s.attributes) - 1
+		}
+	}
+}
+
+// truncateAttr returns a truncated version of attr. Only string and string
+// slice attribute values are truncated. String values are truncated to at
+// most a length of limit. Each string slice value is truncated in this fasion
+// (the slice length itself is unaffected).
+//
+// No truncation is perfromed for a negative limit.
+func truncateAttr(limit int, attr attribute.KeyValue) attribute.KeyValue {
+	if limit < 0 {
+		return attr
+	}
+	switch attr.Value.Type() {
+	case attribute.STRING:
+		if v := attr.Value.AsString(); len(v) > limit {
+			return attr.Key.String(v[:limit])
+		}
+	case attribute.STRINGSLICE:
+		// Do no mutate the original, make a copy.
+		trucated := attr.Key.StringSlice(attr.Value.AsStringSlice())
+		// Do not do this.
+		//
+		//   v := trucated.Value.AsStringSlice()
+		//   cp := make([]string, len(v))
+		//   /* Copy and truncate values to cp ... */
+		//   trucated.Value = attribute.StringSliceValue(cp)
+		//
+		// Copying the []string and then assigning it back as a new value with
+		// attribute.StringSliceValue will copy the data twice. Instead, we
+		// already made a copy above that only this function owns, update the
+		// underlying slice data of our copy.
+		v := trucated.Value.AsStringSlice()
+		for i := range v {
+			if len(v[i]) > limit {
+				v[i] = v[i][:limit]
+			}
+		}
+		return trucated
+	}
+	return attr
+}
+
+// End ends the span. This method does nothing if the span is already ended or
+// is not being recorded.
+//
+// The only SpanOption currently supported is WithTimestamp which will set the
+// end time for a Span's life-cycle.
+//
+// If this method is called while panicking an error event is added to the
+// Span before ending it and the panic is continued.
+func (s *recordingSpan) End(options ...trace.SpanEndOption) {
+	// Do not start by checking if the span is being recorded which requires
+	// acquiring a lock. Make a minimal check that the span is not nil.
+	if s == nil {
+		return
+	}
+
+	// Store the end time as soon as possible to avoid artificially increasing
+	// the span's duration in case some operation below takes a while.
+	et := internal.MonotonicEndTime(s.startTime)
+
+	// Do relative expensive check now that we have an end time and see if we
+	// need to do any more processing.
+	if !s.IsRecording() {
+		return
+	}
+
+	config := trace.NewSpanEndConfig(options...)
+	if recovered := recover(); recovered != nil {
+		// Record but don't stop the panic.
+		defer panic(recovered)
+		opts := []trace.EventOption{
+			trace.WithAttributes(
+				semconv.ExceptionTypeKey.String(typeStr(recovered)),
+				semconv.ExceptionMessageKey.String(fmt.Sprint(recovered)),
+			),
+		}
+
+		if config.StackTrace() {
+			opts = append(opts, trace.WithAttributes(
+				semconv.ExceptionStacktraceKey.String(recordStackTrace()),
+			))
+		}
+
+		s.addEvent(semconv.ExceptionEventName, opts...)
+	}
+
+	if s.executionTracerTaskEnd != nil {
+		s.executionTracerTaskEnd()
+	}
+
+	s.mu.Lock()
+	// Setting endTime to non-zero marks the span as ended and not recording.
+	if config.Timestamp().IsZero() {
+		s.endTime = et
+	} else {
+		s.endTime = config.Timestamp()
+	}
+	s.mu.Unlock()
+
+	if sps, ok := s.tracer.provider.spanProcessors.Load().(spanProcessorStates); ok {
+		if len(sps) == 0 {
+			return
+		}
+		snap := s.snapshot()
+		for _, sp := range sps {
+			sp.sp.OnEnd(snap)
+		}
+	}
+}
+
+// RecordError will record err as a span event for this span. An additional call to
+// SetStatus is required if the Status of the Span should be set to Error, this method
+// does not change the Span status. If this span is not being recorded or err is nil
+// than this method does nothing.
+func (s *recordingSpan) RecordError(err error, opts ...trace.EventOption) {
+	if s == nil || err == nil || !s.IsRecording() {
+		return
+	}
+
+	opts = append(opts, trace.WithAttributes(
+		semconv.ExceptionTypeKey.String(typeStr(err)),
+		semconv.ExceptionMessageKey.String(err.Error()),
+	))
+
+	c := trace.NewEventConfig(opts...)
+	if c.StackTrace() {
+		opts = append(opts, trace.WithAttributes(
+			semconv.ExceptionStacktraceKey.String(recordStackTrace()),
+		))
+	}
+
+	s.addEvent(semconv.ExceptionEventName, opts...)
+}
+
+func typeStr(i interface{}) string {
+	t := reflect.TypeOf(i)
+	if t.PkgPath() == "" && t.Name() == "" {
+		// Likely a builtin type.
+		return t.String()
+	}
+	return fmt.Sprintf("%s.%s", t.PkgPath(), t.Name())
+}
+
+func recordStackTrace() string {
+	stackTrace := make([]byte, 2048)
+	n := runtime.Stack(stackTrace, false)
+
+	return string(stackTrace[0:n])
+}
+
+// AddEvent adds an event with the provided name and options. If this span is
+// not being recorded than this method does nothing.
+func (s *recordingSpan) AddEvent(name string, o ...trace.EventOption) {
+	if !s.IsRecording() {
+		return
+	}
+	s.addEvent(name, o...)
+}
+
+func (s *recordingSpan) addEvent(name string, o ...trace.EventOption) {
+	c := trace.NewEventConfig(o...)
+	e := Event{Name: name, Attributes: c.Attributes(), Time: c.Timestamp()}
+
+	// Discard attributes over limit.
+	limit := s.tracer.provider.spanLimits.AttributePerEventCountLimit
+	if limit == 0 {
+		// Drop all attributes.
+		e.DroppedAttributeCount = len(e.Attributes)
+		e.Attributes = nil
+	} else if limit > 0 && len(e.Attributes) > limit {
+		// Drop over capacity.
+		e.DroppedAttributeCount = len(e.Attributes) - limit
+		e.Attributes = e.Attributes[:limit]
+	}
+
+	s.mu.Lock()
+	s.events.add(e)
+	s.mu.Unlock()
+}
+
+// SetName sets the name of this span. If this span is not being recorded than
+// this method does nothing.
+func (s *recordingSpan) SetName(name string) {
+	if !s.IsRecording() {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.name = name
+}
+
+// Name returns the name of this span.
+func (s *recordingSpan) Name() string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.name
+}
+
+// Name returns the SpanContext of this span's parent span.
+func (s *recordingSpan) Parent() trace.SpanContext {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.parent
+}
+
+// SpanKind returns the SpanKind of this span.
+func (s *recordingSpan) SpanKind() trace.SpanKind {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.spanKind
+}
+
+// StartTime returns the time this span started.
+func (s *recordingSpan) StartTime() time.Time {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.startTime
+}
+
+// EndTime returns the time this span ended. For spans that have not yet
+// ended, the returned value will be the zero value of time.Time.
+func (s *recordingSpan) EndTime() time.Time {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.endTime
+}
+
+// Attributes returns the attributes of this span.
+//
+// The order of the returned attributes is not guaranteed to be stable.
+func (s *recordingSpan) Attributes() []attribute.KeyValue {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.dedupeAttrs()
+	return s.attributes
+}
+
+// dedupeAttrs deduplicates the attributes of s to fit capacity.
+//
+// This method assumes s.mu.Lock is held by the caller.
+func (s *recordingSpan) dedupeAttrs() {
+	// Do not set a capacity when creating this map. Benchmark testing has
+	// showed this to only add unused memory allocations in general use.
+	exists := make(map[attribute.Key]int)
+	s.dedupeAttrsFromRecord(&exists)
+}
+
+// dedupeAttrsFromRecord deduplicates the attributes of s to fit capacity
+// using record as the record of unique attribute keys to their index.
+//
+// This method assumes s.mu.Lock is held by the caller.
+func (s *recordingSpan) dedupeAttrsFromRecord(record *map[attribute.Key]int) {
+	// Use the fact that slices share the same backing array.
+	unique := s.attributes[:0]
+	for _, a := range s.attributes {
+		if idx, ok := (*record)[a.Key]; ok {
+			unique[idx] = a
+		} else {
+			unique = append(unique, a)
+			(*record)[a.Key] = len(unique) - 1
+		}
+	}
+	// s.attributes have element types of attribute.KeyValue. These types are
+	// not pointers and they themselves do not contain pointer fields,
+	// therefore the duplicate values do not need to be zeroed for them to be
+	// garbage collected.
+	s.attributes = unique
+}
+
+// Links returns the links of this span.
+func (s *recordingSpan) Links() []Link {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if len(s.links.queue) == 0 {
+		return []Link{}
+	}
+	return s.interfaceArrayToLinksArray()
+}
+
+// Events returns the events of this span.
+func (s *recordingSpan) Events() []Event {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if len(s.events.queue) == 0 {
+		return []Event{}
+	}
+	return s.interfaceArrayToEventArray()
+}
+
+// Status returns the status of this span.
+func (s *recordingSpan) Status() Status {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.status
+}
+
+// InstrumentationLibrary returns the instrumentation.Library associated with
+// the Tracer that created this span.
+func (s *recordingSpan) InstrumentationLibrary() instrumentation.Library {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.tracer.instrumentationLibrary
+}
+
+// Resource returns the Resource associated with the Tracer that created this
+// span.
+func (s *recordingSpan) Resource() *resource.Resource {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.tracer.provider.resource
+}
+
+func (s *recordingSpan) addLink(link trace.Link) {
+	if !s.IsRecording() || !link.SpanContext.IsValid() {
+		return
+	}
+
+	l := Link{SpanContext: link.SpanContext, Attributes: link.Attributes}
+
+	// Discard attributes over limit.
+	limit := s.tracer.provider.spanLimits.AttributePerLinkCountLimit
+	if limit == 0 {
+		// Drop all attributes.
+		l.DroppedAttributeCount = len(l.Attributes)
+		l.Attributes = nil
+	} else if limit > 0 && len(l.Attributes) > limit {
+		l.DroppedAttributeCount = len(l.Attributes) - limit
+		l.Attributes = l.Attributes[:limit]
+	}
+
+	s.mu.Lock()
+	s.links.add(l)
+	s.mu.Unlock()
+}
+
+// DroppedAttributes returns the number of attributes dropped by the span
+// due to limits being reached.
+func (s *recordingSpan) DroppedAttributes() int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.droppedAttributes
+}
+
+// DroppedLinks returns the number of links dropped by the span due to limits
+// being reached.
+func (s *recordingSpan) DroppedLinks() int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.links.droppedCount
+}
+
+// DroppedEvents returns the number of events dropped by the span due to
+// limits being reached.
+func (s *recordingSpan) DroppedEvents() int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.events.droppedCount
+}
+
+// ChildSpanCount returns the count of spans that consider the span a
+// direct parent.
+func (s *recordingSpan) ChildSpanCount() int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.childSpanCount
+}
+
+// TracerProvider returns a trace.TracerProvider that can be used to generate
+// additional Spans on the same telemetry pipeline as the current Span.
+func (s *recordingSpan) TracerProvider() trace.TracerProvider {
+	return s.tracer.provider
+}
+
+// snapshot creates a read-only copy of the current state of the span.
+func (s *recordingSpan) snapshot() ReadOnlySpan {
+	var sd snapshot
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	sd.endTime = s.endTime
+	sd.instrumentationLibrary = s.tracer.instrumentationLibrary
+	sd.name = s.name
+	sd.parent = s.parent
+	sd.resource = s.tracer.provider.resource
+	sd.spanContext = s.spanContext
+	sd.spanKind = s.spanKind
+	sd.startTime = s.startTime
+	sd.status = s.status
+	sd.childSpanCount = s.childSpanCount
+
+	if len(s.attributes) > 0 {
+		s.dedupeAttrs()
+		sd.attributes = s.attributes
+	}
+	sd.droppedAttributeCount = s.droppedAttributes
+	if len(s.events.queue) > 0 {
+		sd.events = s.interfaceArrayToEventArray()
+		sd.droppedEventCount = s.events.droppedCount
+	}
+	if len(s.links.queue) > 0 {
+		sd.links = s.interfaceArrayToLinksArray()
+		sd.droppedLinkCount = s.links.droppedCount
+	}
+	return &sd
+}
+
+func (s *recordingSpan) interfaceArrayToLinksArray() []Link {
+	linkArr := make([]Link, 0)
+	for _, value := range s.links.queue {
+		linkArr = append(linkArr, value.(Link))
+	}
+	return linkArr
+}
+
+func (s *recordingSpan) interfaceArrayToEventArray() []Event {
+	eventArr := make([]Event, 0)
+	for _, value := range s.events.queue {
+		eventArr = append(eventArr, value.(Event))
+	}
+	return eventArr
+}
+
+func (s *recordingSpan) addChild() {
+	if !s.IsRecording() {
+		return
+	}
+	s.mu.Lock()
+	s.childSpanCount++
+	s.mu.Unlock()
+}
+
+func (*recordingSpan) private() {}
+
+// runtimeTrace starts a "runtime/trace".Task for the span and returns a
+// context containing the task.
+func (s *recordingSpan) runtimeTrace(ctx context.Context) context.Context {
+	if !rt.IsEnabled() {
+		// Avoid additional overhead if runtime/trace is not enabled.
+		return ctx
+	}
+	nctx, task := rt.NewTask(ctx, s.name)
+
+	s.mu.Lock()
+	s.executionTracerTaskEnd = task.End
+	s.mu.Unlock()
+
+	return nctx
+}
+
+// nonRecordingSpan is a minimal implementation of the OpenTelemetry Span API
+// that wraps a SpanContext. It performs no operations other than to return
+// the wrapped SpanContext or TracerProvider that created it.
+type nonRecordingSpan struct {
+	// tracer is the SDK tracer that created this span.
+	tracer *tracer
+	sc     trace.SpanContext
+}
+
+var _ trace.Span = nonRecordingSpan{}
+
+// SpanContext returns the wrapped SpanContext.
+func (s nonRecordingSpan) SpanContext() trace.SpanContext { return s.sc }
+
+// IsRecording always returns false.
+func (nonRecordingSpan) IsRecording() bool { return false }
+
+// SetStatus does nothing.
+func (nonRecordingSpan) SetStatus(codes.Code, string) {}
+
+// SetError does nothing.
+func (nonRecordingSpan) SetError(bool) {}
+
+// SetAttributes does nothing.
+func (nonRecordingSpan) SetAttributes(...attribute.KeyValue) {}
+
+// End does nothing.
+func (nonRecordingSpan) End(...trace.SpanEndOption) {}
+
+// RecordError does nothing.
+func (nonRecordingSpan) RecordError(error, ...trace.EventOption) {}
+
+// AddEvent does nothing.
+func (nonRecordingSpan) AddEvent(string, ...trace.EventOption) {}
+
+// SetName does nothing.
+func (nonRecordingSpan) SetName(string) {}
+
+// TracerProvider returns the trace.TracerProvider that provided the Tracer
+// that created this span.
+func (s nonRecordingSpan) TracerProvider() trace.TracerProvider { return s.tracer.provider }
+
+func isRecording(s SamplingResult) bool {
+	return s.Decision == RecordOnly || s.Decision == RecordAndSample
+}
+
+func isSampled(s SamplingResult) bool {
+	return s.Decision == RecordAndSample
+}
+
+// Status is the classified state of a Span.
+type Status struct {
+	// Code is an identifier of a Spans state classification.
+	Code codes.Code
+	// Description is a user hint about why that status was set. It is only
+	// applicable when Code is Error.
+	Description string
+}

vendor/go.opentelemetry.io/otel/sdk/trace/span_exporter.go

@@ -0,0 +1,47 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import "context"
+
+// SpanExporter handles the delivery of spans to external receivers. This is
+// the final component in the trace export pipeline.
+type SpanExporter interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// ExportSpans exports a batch of spans.
+	//
+	// This function is called synchronously, so there is no concurrency
+	// safety requirement. However, due to the synchronous calling pattern,
+	// it is critical that all timeouts and cancellations contained in the
+	// passed context must be honored.
+	//
+	// Any retry logic must be contained in this function. The SDK that
+	// calls this function will not implement any retry logic. All errors
+	// returned by this function are considered unrecoverable and will be
+	// reported to a configured error Handler.
+	ExportSpans(ctx context.Context, spans []ReadOnlySpan) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Shutdown notifies the exporter of a pending halt to operations. The
+	// exporter is expected to preform any cleanup or synchronization it
+	// requires while honoring all timeouts and cancellations contained in
+	// the passed context.
+	Shutdown(ctx context.Context) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}

vendor/go.opentelemetry.io/otel/sdk/trace/span_limits.go

@@ -0,0 +1,126 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import "go.opentelemetry.io/otel/sdk/internal/env"
+
+const (
+	// DefaultAttributeValueLengthLimit is the default maximum allowed
+	// attribute value length, unlimited.
+	DefaultAttributeValueLengthLimit = -1
+
+	// DefaultAttributeCountLimit is the default maximum number of attributes
+	// a span can have.
+	DefaultAttributeCountLimit = 128
+
+	// DefaultEventCountLimit is the default maximum number of events a span
+	// can have.
+	DefaultEventCountLimit = 128
+
+	// DefaultLinkCountLimit is the default maximum number of links a span can
+	// have.
+	DefaultLinkCountLimit = 128
+
+	// DefaultAttributePerEventCountLimit is the default maximum number of
+	// attributes a span event can have.
+	DefaultAttributePerEventCountLimit = 128
+
+	// DefaultAttributePerLinkCountLimit is the default maximum number of
+	// attributes a span link can have.
+	DefaultAttributePerLinkCountLimit = 128
+)
+
+// SpanLimits represents the limits of a span.
+type SpanLimits struct {
+	// AttributeValueLengthLimit is the maximum allowed attribute value length.
+	//
+	// This limit only applies to string and string slice attribute values.
+	// Any string longer than this value will be truncated to this length.
+	//
+	// Setting this to a negative value means no limit is applied.
+	AttributeValueLengthLimit int
+
+	// AttributeCountLimit is the maximum allowed span attribute count. Any
+	// attribute added to a span once this limit is reached will be dropped.
+	//
+	// Setting this to zero means no attributes will be recorded.
+	//
+	// Setting this to a negative value means no limit is applied.
+	AttributeCountLimit int
+
+	// EventCountLimit is the maximum allowed span event count. Any event
+	// added to a span once this limit is reached means it will be added but
+	// the oldest event will be dropped.
+	//
+	// Setting this to zero means no events we be recorded.
+	//
+	// Setting this to a negative value means no limit is applied.
+	EventCountLimit int
+
+	// LinkCountLimit is the maximum allowed span link count. Any link added
+	// to a span once this limit is reached means it will be added but the
+	// oldest link will be dropped.
+	//
+	// Setting this to zero means no links we be recorded.
+	//
+	// Setting this to a negative value means no limit is applied.
+	LinkCountLimit int
+
+	// AttributePerEventCountLimit is the maximum number of attributes allowed
+	// per span event. Any attribute added after this limit reached will be
+	// dropped.
+	//
+	// Setting this to zero means no attributes will be recorded for events.
+	//
+	// Setting this to a negative value means no limit is applied.
+	AttributePerEventCountLimit int
+
+	// AttributePerLinkCountLimit is the maximum number of attributes allowed
+	// per span link. Any attribute added after this limit reached will be
+	// dropped.
+	//
+	// Setting this to zero means no attributes will be recorded for links.
+	//
+	// Setting this to a negative value means no limit is applied.
+	AttributePerLinkCountLimit int
+}
+
+// NewSpanLimits returns a SpanLimits with all limits set to the value their
+// corresponding environment variable holds, or the default if unset.
+//
+// • AttributeValueLengthLimit: OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT
+// (default: unlimited)
+//
+// • AttributeCountLimit: OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT (default: 128)
+//
+// • EventCountLimit: OTEL_SPAN_EVENT_COUNT_LIMIT (default: 128)
+//
+// • AttributePerEventCountLimit: OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT (default:
+// 128)
+//
+// • LinkCountLimit: OTEL_SPAN_LINK_COUNT_LIMIT (default: 128)
+//
+// • AttributePerLinkCountLimit: OTEL_LINK_ATTRIBUTE_COUNT_LIMIT (default:
+// 128)
+func NewSpanLimits() SpanLimits {
+	return SpanLimits{
+		AttributeValueLengthLimit:   env.SpanAttributeValueLength(DefaultAttributeValueLengthLimit),
+		AttributeCountLimit:         env.SpanAttributeCount(DefaultAttributeCountLimit),
+		EventCountLimit:             env.SpanEventCount(DefaultEventCountLimit),
+		LinkCountLimit:              env.SpanLinkCount(DefaultLinkCountLimit),
+		AttributePerEventCountLimit: env.SpanEventAttributeCount(DefaultAttributePerEventCountLimit),
+		AttributePerLinkCountLimit:  env.SpanLinkAttributeCount(DefaultAttributePerLinkCountLimit),
+	}
+}

vendor/go.opentelemetry.io/otel/sdk/trace/span_processor.go

@@ -0,0 +1,67 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"sync"
+)
+
+// SpanProcessor is a processing pipeline for spans in the trace signal.
+// SpanProcessors registered with a TracerProvider and are called at the start
+// and end of a Span's lifecycle, and are called in the order they are
+// registered.
+type SpanProcessor interface {
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// OnStart is called when a span is started. It is called synchronously
+	// and should not block.
+	OnStart(parent context.Context, s ReadWriteSpan)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// OnEnd is called when span is finished. It is called synchronously and
+	// hence not block.
+	OnEnd(s ReadOnlySpan)
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// Shutdown is called when the SDK shuts down. Any cleanup or release of
+	// resources held by the processor should be done in this call.
+	//
+	// Calls to OnStart, OnEnd, or ForceFlush after this has been called
+	// should be ignored.
+	//
+	// All timeouts and cancellations contained in ctx must be honored, this
+	// should not block indefinitely.
+	Shutdown(ctx context.Context) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+
+	// ForceFlush exports all ended spans to the configured Exporter that have not yet
+	// been exported.  It should only be called when absolutely necessary, such as when
+	// using a FaaS provider that may suspend the process after an invocation, but before
+	// the Processor can export the completed spans.
+	ForceFlush(ctx context.Context) error
+	// DO NOT CHANGE: any modification will not be backwards compatible and
+	// must never be done outside of a new major release.
+}
+
+type spanProcessorState struct {
+	sp    SpanProcessor
+	state *sync.Once
+}
+type spanProcessorStates []*spanProcessorState

vendor/go.opentelemetry.io/otel/sdk/trace/tracer.go

@@ -0,0 +1,156 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/sdk/trace"
+
+import (
+	"context"
+	"time"
+
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type tracer struct {
+	provider               *TracerProvider
+	instrumentationLibrary instrumentation.Library
+}
+
+var _ trace.Tracer = &tracer{}
+
+// Start starts a Span and returns it along with a context containing it.
+//
+// The Span is created with the provided name and as a child of any existing
+// span context found in the passed context. The created Span will be
+// configured appropriately by any SpanOption passed.
+func (tr *tracer) Start(ctx context.Context, name string, options ...trace.SpanStartOption) (context.Context, trace.Span) {
+	config := trace.NewSpanStartConfig(options...)
+
+	// For local spans created by this SDK, track child span count.
+	if p := trace.SpanFromContext(ctx); p != nil {
+		if sdkSpan, ok := p.(*recordingSpan); ok {
+			sdkSpan.addChild()
+		}
+	}
+
+	s := tr.newSpan(ctx, name, &config)
+	if rw, ok := s.(ReadWriteSpan); ok && s.IsRecording() {
+		sps, _ := tr.provider.spanProcessors.Load().(spanProcessorStates)
+		for _, sp := range sps {
+			sp.sp.OnStart(ctx, rw)
+		}
+	}
+	if rtt, ok := s.(runtimeTracer); ok {
+		ctx = rtt.runtimeTrace(ctx)
+	}
+
+	return trace.ContextWithSpan(ctx, s), s
+}
+
+type runtimeTracer interface {
+	// runtimeTrace starts a "runtime/trace".Task for the span and
+	// returns a context containing the task.
+	runtimeTrace(ctx context.Context) context.Context
+}
+
+// newSpan returns a new configured span.
+func (tr *tracer) newSpan(ctx context.Context, name string, config *trace.SpanConfig) trace.Span {
+	// If told explicitly to make this a new root use a zero value SpanContext
+	// as a parent which contains an invalid trace ID and is not remote.
+	var psc trace.SpanContext
+	if config.NewRoot() {
+		ctx = trace.ContextWithSpanContext(ctx, psc)
+	} else {
+		psc = trace.SpanContextFromContext(ctx)
+	}
+
+	// If there is a valid parent trace ID, use it to ensure the continuity of
+	// the trace. Always generate a new span ID so other components can rely
+	// on a unique span ID, even if the Span is non-recording.
+	var tid trace.TraceID
+	var sid trace.SpanID
+	if !psc.TraceID().IsValid() {
+		tid, sid = tr.provider.idGenerator.NewIDs(ctx)
+	} else {
+		tid = psc.TraceID()
+		sid = tr.provider.idGenerator.NewSpanID(ctx, tid)
+	}
+
+	samplingResult := tr.provider.sampler.ShouldSample(SamplingParameters{
+		ParentContext: ctx,
+		TraceID:       tid,
+		Name:          name,
+		Kind:          config.SpanKind(),
+		Attributes:    config.Attributes(),
+		Links:         config.Links(),
+	})
+
+	scc := trace.SpanContextConfig{
+		TraceID:    tid,
+		SpanID:     sid,
+		TraceState: samplingResult.Tracestate,
+	}
+	if isSampled(samplingResult) {
+		scc.TraceFlags = psc.TraceFlags() | trace.FlagsSampled
+	} else {
+		scc.TraceFlags = psc.TraceFlags() &^ trace.FlagsSampled
+	}
+	sc := trace.NewSpanContext(scc)
+
+	if !isRecording(samplingResult) {
+		return tr.newNonRecordingSpan(sc)
+	}
+	return tr.newRecordingSpan(psc, sc, name, samplingResult, config)
+}
+
+// newRecordingSpan returns a new configured recordingSpan.
+func (tr *tracer) newRecordingSpan(psc, sc trace.SpanContext, name string, sr SamplingResult, config *trace.SpanConfig) *recordingSpan {
+	startTime := config.Timestamp()
+	if startTime.IsZero() {
+		startTime = time.Now()
+	}
+
+	s := &recordingSpan{
+		// Do not pre-allocate the attributes slice here! Doing so will
+		// allocate memory that is likely never going to be used, or if used,
+		// will be over-sized. The default Go compiler has been tested to
+		// dynamically allocate needed space very well. Benchmarking has shown
+		// it to be more performant than what we can predetermine here,
+		// especially for the common use case of few to no added
+		// attributes.
+
+		parent:      psc,
+		spanContext: sc,
+		spanKind:    trace.ValidateSpanKind(config.SpanKind()),
+		name:        name,
+		startTime:   startTime,
+		events:      newEvictedQueue(tr.provider.spanLimits.EventCountLimit),
+		links:       newEvictedQueue(tr.provider.spanLimits.LinkCountLimit),
+		tracer:      tr,
+	}
+
+	for _, l := range config.Links() {
+		s.addLink(l)
+	}
+
+	s.SetAttributes(sr.Attributes...)
+	s.SetAttributes(config.Attributes()...)
+
+	return s
+}
+
+// newNonRecordingSpan returns a new configured nonRecordingSpan.
+func (tr *tracer) newNonRecordingSpan(sc trace.SpanContext) nonRecordingSpan {
+	return nonRecordingSpan{tracer: tr, sc: sc}
+}

vendor/go.opentelemetry.io/otel/semconv/v1.7.0/doc.go

@@ -0,0 +1,20 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package semconv implements OpenTelemetry semantic conventions.
+//
+// OpenTelemetry semantic conventions are agreed standardized naming
+// patterns for OpenTelemetry things. This package represents the conventions
+// as of the v1.7.0 version of the OpenTelemetry specification.
+package semconv // import "go.opentelemetry.io/otel/semconv/v1.7.0"

vendor/go.opentelemetry.io/otel/semconv/v1.7.0/exception.go

@@ -0,0 +1,20 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package semconv // import "go.opentelemetry.io/otel/semconv/v1.7.0"
+
+const (
+	// ExceptionEventName is the name of the Span event representing an exception.
+	ExceptionEventName = "exception"
+)

vendor/go.opentelemetry.io/otel/semconv/v1.7.0/http.go

@@ -0,0 +1,314 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package semconv // import "go.opentelemetry.io/otel/semconv/v1.7.0"
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"go.opentelemetry.io/otel/trace"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+)
+
+// HTTP scheme attributes.
+var (
+	HTTPSchemeHTTP  = HTTPSchemeKey.String("http")
+	HTTPSchemeHTTPS = HTTPSchemeKey.String("https")
+)
+
+// NetAttributesFromHTTPRequest generates attributes of the net
+// namespace as specified by the OpenTelemetry specification for a
+// span.  The network parameter is a string that net.Dial function
+// from standard library can understand.
+func NetAttributesFromHTTPRequest(network string, request *http.Request) []attribute.KeyValue {
+	attrs := []attribute.KeyValue{}
+
+	switch network {
+	case "tcp", "tcp4", "tcp6":
+		attrs = append(attrs, NetTransportTCP)
+	case "udp", "udp4", "udp6":
+		attrs = append(attrs, NetTransportUDP)
+	case "ip", "ip4", "ip6":
+		attrs = append(attrs, NetTransportIP)
+	case "unix", "unixgram", "unixpacket":
+		attrs = append(attrs, NetTransportUnix)
+	default:
+		attrs = append(attrs, NetTransportOther)
+	}
+
+	peerIP, peerName, peerPort := hostIPNamePort(request.RemoteAddr)
+	if peerIP != "" {
+		attrs = append(attrs, NetPeerIPKey.String(peerIP))
+	}
+	if peerName != "" {
+		attrs = append(attrs, NetPeerNameKey.String(peerName))
+	}
+	if peerPort != 0 {
+		attrs = append(attrs, NetPeerPortKey.Int(peerPort))
+	}
+
+	hostIP, hostName, hostPort := "", "", 0
+	for _, someHost := range []string{request.Host, request.Header.Get("Host"), request.URL.Host} {
+		hostIP, hostName, hostPort = hostIPNamePort(someHost)
+		if hostIP != "" || hostName != "" || hostPort != 0 {
+			break
+		}
+	}
+	if hostIP != "" {
+		attrs = append(attrs, NetHostIPKey.String(hostIP))
+	}
+	if hostName != "" {
+		attrs = append(attrs, NetHostNameKey.String(hostName))
+	}
+	if hostPort != 0 {
+		attrs = append(attrs, NetHostPortKey.Int(hostPort))
+	}
+
+	return attrs
+}
+
+// hostIPNamePort extracts the IP address, name and (optional) port from hostWithPort.
+// It handles both IPv4 and IPv6 addresses. If the host portion is not recognized
+// as a valid IPv4 or IPv6 address, the `ip` result will be empty and the
+// host portion will instead be returned in `name`.
+func hostIPNamePort(hostWithPort string) (ip string, name string, port int) {
+	var (
+		hostPart, portPart string
+		parsedPort         uint64
+		err                error
+	)
+	if hostPart, portPart, err = net.SplitHostPort(hostWithPort); err != nil {
+		hostPart, portPart = hostWithPort, ""
+	}
+	if parsedIP := net.ParseIP(hostPart); parsedIP != nil {
+		ip = parsedIP.String()
+	} else {
+		name = hostPart
+	}
+	if parsedPort, err = strconv.ParseUint(portPart, 10, 16); err == nil {
+		port = int(parsedPort)
+	}
+	return
+}
+
+// EndUserAttributesFromHTTPRequest generates attributes of the
+// enduser namespace as specified by the OpenTelemetry specification
+// for a span.
+func EndUserAttributesFromHTTPRequest(request *http.Request) []attribute.KeyValue {
+	if username, _, ok := request.BasicAuth(); ok {
+		return []attribute.KeyValue{EnduserIDKey.String(username)}
+	}
+	return nil
+}
+
+// HTTPClientAttributesFromHTTPRequest generates attributes of the
+// http namespace as specified by the OpenTelemetry specification for
+// a span on the client side.
+func HTTPClientAttributesFromHTTPRequest(request *http.Request) []attribute.KeyValue {
+	attrs := []attribute.KeyValue{}
+
+	if request.Method != "" {
+		attrs = append(attrs, HTTPMethodKey.String(request.Method))
+	} else {
+		attrs = append(attrs, HTTPMethodKey.String(http.MethodGet))
+	}
+
+	// remove any username/password info that may be in the URL
+	// before adding it to the attributes
+	userinfo := request.URL.User
+	request.URL.User = nil
+
+	attrs = append(attrs, HTTPURLKey.String(request.URL.String()))
+
+	// restore any username/password info that was removed
+	request.URL.User = userinfo
+
+	return append(attrs, httpCommonAttributesFromHTTPRequest(request)...)
+}
+
+func httpCommonAttributesFromHTTPRequest(request *http.Request) []attribute.KeyValue {
+	attrs := []attribute.KeyValue{}
+	if ua := request.UserAgent(); ua != "" {
+		attrs = append(attrs, HTTPUserAgentKey.String(ua))
+	}
+	if request.ContentLength > 0 {
+		attrs = append(attrs, HTTPRequestContentLengthKey.Int64(request.ContentLength))
+	}
+
+	return append(attrs, httpBasicAttributesFromHTTPRequest(request)...)
+}
+
+func httpBasicAttributesFromHTTPRequest(request *http.Request) []attribute.KeyValue {
+	// as these attributes are used by HTTPServerMetricAttributesFromHTTPRequest, they should be low-cardinality
+	attrs := []attribute.KeyValue{}
+
+	if request.TLS != nil {
+		attrs = append(attrs, HTTPSchemeHTTPS)
+	} else {
+		attrs = append(attrs, HTTPSchemeHTTP)
+	}
+
+	if request.Host != "" {
+		attrs = append(attrs, HTTPHostKey.String(request.Host))
+	} else if request.URL != nil && request.URL.Host != "" {
+		attrs = append(attrs, HTTPHostKey.String(request.URL.Host))
+	}
+
+	flavor := ""
+	if request.ProtoMajor == 1 {
+		flavor = fmt.Sprintf("1.%d", request.ProtoMinor)
+	} else if request.ProtoMajor == 2 {
+		flavor = "2"
+	}
+	if flavor != "" {
+		attrs = append(attrs, HTTPFlavorKey.String(flavor))
+	}
+
+	return attrs
+}
+
+// HTTPServerMetricAttributesFromHTTPRequest generates low-cardinality attributes
+// to be used with server-side HTTP metrics.
+func HTTPServerMetricAttributesFromHTTPRequest(serverName string, request *http.Request) []attribute.KeyValue {
+	attrs := []attribute.KeyValue{}
+	if serverName != "" {
+		attrs = append(attrs, HTTPServerNameKey.String(serverName))
+	}
+	return append(attrs, httpBasicAttributesFromHTTPRequest(request)...)
+}
+
+// HTTPServerAttributesFromHTTPRequest generates attributes of the
+// http namespace as specified by the OpenTelemetry specification for
+// a span on the server side. Currently, only basic authentication is
+// supported.
+func HTTPServerAttributesFromHTTPRequest(serverName, route string, request *http.Request) []attribute.KeyValue {
+	attrs := []attribute.KeyValue{
+		HTTPMethodKey.String(request.Method),
+		HTTPTargetKey.String(request.RequestURI),
+	}
+
+	if serverName != "" {
+		attrs = append(attrs, HTTPServerNameKey.String(serverName))
+	}
+	if route != "" {
+		attrs = append(attrs, HTTPRouteKey.String(route))
+	}
+	if values, ok := request.Header["X-Forwarded-For"]; ok && len(values) > 0 {
+		if addresses := strings.SplitN(values[0], ",", 2); len(addresses) > 0 {
+			attrs = append(attrs, HTTPClientIPKey.String(addresses[0]))
+		}
+	}
+
+	return append(attrs, httpCommonAttributesFromHTTPRequest(request)...)
+}
+
+// HTTPAttributesFromHTTPStatusCode generates attributes of the http
+// namespace as specified by the OpenTelemetry specification for a
+// span.
+func HTTPAttributesFromHTTPStatusCode(code int) []attribute.KeyValue {
+	attrs := []attribute.KeyValue{
+		HTTPStatusCodeKey.Int(code),
+	}
+	return attrs
+}
+
+type codeRange struct {
+	fromInclusive int
+	toInclusive   int
+}
+
+func (r codeRange) contains(code int) bool {
+	return r.fromInclusive <= code && code <= r.toInclusive
+}
+
+var validRangesPerCategory = map[int][]codeRange{
+	1: {
+		{http.StatusContinue, http.StatusEarlyHints},
+	},
+	2: {
+		{http.StatusOK, http.StatusAlreadyReported},
+		{http.StatusIMUsed, http.StatusIMUsed},
+	},
+	3: {
+		{http.StatusMultipleChoices, http.StatusUseProxy},
+		{http.StatusTemporaryRedirect, http.StatusPermanentRedirect},
+	},
+	4: {
+		{http.StatusBadRequest, http.StatusTeapot}, // yes, teapot is so useful…
+		{http.StatusMisdirectedRequest, http.StatusUpgradeRequired},
+		{http.StatusPreconditionRequired, http.StatusTooManyRequests},
+		{http.StatusRequestHeaderFieldsTooLarge, http.StatusRequestHeaderFieldsTooLarge},
+		{http.StatusUnavailableForLegalReasons, http.StatusUnavailableForLegalReasons},
+	},
+	5: {
+		{http.StatusInternalServerError, http.StatusLoopDetected},
+		{http.StatusNotExtended, http.StatusNetworkAuthenticationRequired},
+	},
+}
+
+// SpanStatusFromHTTPStatusCode generates a status code and a message
+// as specified by the OpenTelemetry specification for a span.
+func SpanStatusFromHTTPStatusCode(code int) (codes.Code, string) {
+	spanCode, valid := validateHTTPStatusCode(code)
+	if !valid {
+		return spanCode, fmt.Sprintf("Invalid HTTP status code %d", code)
+	}
+	return spanCode, ""
+}
+
+// SpanStatusFromHTTPStatusCodeAndSpanKind generates a status code and a message
+// as specified by the OpenTelemetry specification for a span.
+// Exclude 4xx for SERVER to set the appropriate status.
+func SpanStatusFromHTTPStatusCodeAndSpanKind(code int, spanKind trace.SpanKind) (codes.Code, string) {
+	spanCode, valid := validateHTTPStatusCode(code)
+	if !valid {
+		return spanCode, fmt.Sprintf("Invalid HTTP status code %d", code)
+	}
+	category := code / 100
+	if spanKind == trace.SpanKindServer && category == 4 {
+		return codes.Unset, ""
+	}
+	return spanCode, ""
+}
+
+// Validates the HTTP status code and returns corresponding span status code.
+// If the `code` is not a valid HTTP status code, returns span status Error
+// and false.
+func validateHTTPStatusCode(code int) (codes.Code, bool) {
+	category := code / 100
+	ranges, ok := validRangesPerCategory[category]
+	if !ok {
+		return codes.Error, false
+	}
+	ok = false
+	for _, crange := range ranges {
+		ok = crange.contains(code)
+		if ok {
+			break
+		}
+	}
+	if !ok {
+		return codes.Error, false
+	}
+	if category > 0 && category < 4 {
+		return codes.Unset, true
+	}
+	return codes.Error, true
+}

vendor/go.opentelemetry.io/otel/semconv/v1.7.0/resource.go

@@ -0,0 +1,946 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Code generated from semantic convention specification. DO NOT EDIT.
+
+package semconv // import "go.opentelemetry.io/otel/semconv/v1.7.0"
+
+import "go.opentelemetry.io/otel/attribute"
+
+// A cloud environment (e.g. GCP, Azure, AWS)
+const (
+	// Name of the cloud provider.
+	//
+	// Type: Enum
+	// Required: No
+	// Stability: stable
+	CloudProviderKey = attribute.Key("cloud.provider")
+	// The cloud account ID the resource is assigned to.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '111111111111', 'opentelemetry'
+	CloudAccountIDKey = attribute.Key("cloud.account.id")
+	// The geographical region the resource is running. Refer to your provider's docs
+	// to see the available regions, for example [Alibaba Cloud
+	// regions](https://www.alibabacloud.com/help/doc-detail/40654.htm), [AWS
+	// regions](https://aws.amazon.com/about-aws/global-infrastructure/regions_az/),
+	// [Azure regions](https://azure.microsoft.com/en-us/global-
+	// infrastructure/geographies/), or [Google Cloud
+	// regions](https://cloud.google.com/about/locations).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'us-central1', 'us-east-1'
+	CloudRegionKey = attribute.Key("cloud.region")
+	// Cloud regions often have multiple, isolated locations known as zones to
+	// increase availability. Availability zone represents the zone where the resource
+	// is running.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'us-east-1c'
+	// Note: Availability zones are called "zones" on Alibaba Cloud and Google Cloud.
+	CloudAvailabilityZoneKey = attribute.Key("cloud.availability_zone")
+	// The cloud platform in use.
+	//
+	// Type: Enum
+	// Required: No
+	// Stability: stable
+	// Note: The prefix of the service SHOULD match the one specified in
+	// `cloud.provider`.
+	CloudPlatformKey = attribute.Key("cloud.platform")
+)
+
+var (
+	// Alibaba Cloud
+	CloudProviderAlibabaCloud = CloudProviderKey.String("alibaba_cloud")
+	// Amazon Web Services
+	CloudProviderAWS = CloudProviderKey.String("aws")
+	// Microsoft Azure
+	CloudProviderAzure = CloudProviderKey.String("azure")
+	// Google Cloud Platform
+	CloudProviderGCP = CloudProviderKey.String("gcp")
+)
+
+var (
+	// Alibaba Cloud Elastic Compute Service
+	CloudPlatformAlibabaCloudECS = CloudPlatformKey.String("alibaba_cloud_ecs")
+	// Alibaba Cloud Function Compute
+	CloudPlatformAlibabaCloudFc = CloudPlatformKey.String("alibaba_cloud_fc")
+	// AWS Elastic Compute Cloud
+	CloudPlatformAWSEC2 = CloudPlatformKey.String("aws_ec2")
+	// AWS Elastic Container Service
+	CloudPlatformAWSECS = CloudPlatformKey.String("aws_ecs")
+	// AWS Elastic Kubernetes Service
+	CloudPlatformAWSEKS = CloudPlatformKey.String("aws_eks")
+	// AWS Lambda
+	CloudPlatformAWSLambda = CloudPlatformKey.String("aws_lambda")
+	// AWS Elastic Beanstalk
+	CloudPlatformAWSElasticBeanstalk = CloudPlatformKey.String("aws_elastic_beanstalk")
+	// Azure Virtual Machines
+	CloudPlatformAzureVM = CloudPlatformKey.String("azure_vm")
+	// Azure Container Instances
+	CloudPlatformAzureContainerInstances = CloudPlatformKey.String("azure_container_instances")
+	// Azure Kubernetes Service
+	CloudPlatformAzureAKS = CloudPlatformKey.String("azure_aks")
+	// Azure Functions
+	CloudPlatformAzureFunctions = CloudPlatformKey.String("azure_functions")
+	// Azure App Service
+	CloudPlatformAzureAppService = CloudPlatformKey.String("azure_app_service")
+	// Google Cloud Compute Engine (GCE)
+	CloudPlatformGCPComputeEngine = CloudPlatformKey.String("gcp_compute_engine")
+	// Google Cloud Run
+	CloudPlatformGCPCloudRun = CloudPlatformKey.String("gcp_cloud_run")
+	// Google Cloud Kubernetes Engine (GKE)
+	CloudPlatformGCPKubernetesEngine = CloudPlatformKey.String("gcp_kubernetes_engine")
+	// Google Cloud Functions (GCF)
+	CloudPlatformGCPCloudFunctions = CloudPlatformKey.String("gcp_cloud_functions")
+	// Google Cloud App Engine (GAE)
+	CloudPlatformGCPAppEngine = CloudPlatformKey.String("gcp_app_engine")
+)
+
+// Resources used by AWS Elastic Container Service (ECS).
+const (
+	// The Amazon Resource Name (ARN) of an [ECS container instance](https://docs.aws.
+	// amazon.com/AmazonECS/latest/developerguide/ECS_instances.html).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:ecs:us-
+	// west-1:123456789123:container/32624152-9086-4f0e-acae-1a75b14fe4d9'
+	AWSECSContainerARNKey = attribute.Key("aws.ecs.container.arn")
+	// The ARN of an [ECS cluster](https://docs.aws.amazon.com/AmazonECS/latest/develo
+	// perguide/clusters.html).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:ecs:us-west-2:123456789123:cluster/my-cluster'
+	AWSECSClusterARNKey = attribute.Key("aws.ecs.cluster.arn")
+	// The [launch type](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/l
+	// aunch_types.html) for an ECS task.
+	//
+	// Type: Enum
+	// Required: No
+	// Stability: stable
+	AWSECSLaunchtypeKey = attribute.Key("aws.ecs.launchtype")
+	// The ARN of an [ECS task definition](https://docs.aws.amazon.com/AmazonECS/lates
+	// t/developerguide/task_definitions.html).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:ecs:us-
+	// west-1:123456789123:task/10838bed-421f-43ef-870a-f43feacbbb5b'
+	AWSECSTaskARNKey = attribute.Key("aws.ecs.task.arn")
+	// The task definition family this task definition is a member of.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry-family'
+	AWSECSTaskFamilyKey = attribute.Key("aws.ecs.task.family")
+	// The revision for this task definition.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '8', '26'
+	AWSECSTaskRevisionKey = attribute.Key("aws.ecs.task.revision")
+)
+
+var (
+	// ec2
+	AWSECSLaunchtypeEC2 = AWSECSLaunchtypeKey.String("ec2")
+	// fargate
+	AWSECSLaunchtypeFargate = AWSECSLaunchtypeKey.String("fargate")
+)
+
+// Resources used by AWS Elastic Kubernetes Service (EKS).
+const (
+	// The ARN of an EKS cluster.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:ecs:us-west-2:123456789123:cluster/my-cluster'
+	AWSEKSClusterARNKey = attribute.Key("aws.eks.cluster.arn")
+)
+
+// Resources specific to Amazon Web Services.
+const (
+	// The name(s) of the AWS log group(s) an application is writing to.
+	//
+	// Type: string[]
+	// Required: No
+	// Stability: stable
+	// Examples: '/aws/lambda/my-function', 'opentelemetry-service'
+	// Note: Multiple log groups must be supported for cases like multi-container
+	// applications, where a single application has sidecar containers, and each write
+	// to their own log group.
+	AWSLogGroupNamesKey = attribute.Key("aws.log.group.names")
+	// The Amazon Resource Name(s) (ARN) of the AWS log group(s).
+	//
+	// Type: string[]
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:logs:us-west-1:123456789012:log-group:/aws/my/group:*'
+	// Note: See the [log group ARN format
+	// documentation](https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/iam-
+	// access-control-overview-cwl.html#CWL_ARN_Format).
+	AWSLogGroupARNsKey = attribute.Key("aws.log.group.arns")
+	// The name(s) of the AWS log stream(s) an application is writing to.
+	//
+	// Type: string[]
+	// Required: No
+	// Stability: stable
+	// Examples: 'logs/main/10838bed-421f-43ef-870a-f43feacbbb5b'
+	AWSLogStreamNamesKey = attribute.Key("aws.log.stream.names")
+	// The ARN(s) of the AWS log stream(s).
+	//
+	// Type: string[]
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:logs:us-west-1:123456789012:log-group:/aws/my/group:log-
+	// stream:logs/main/10838bed-421f-43ef-870a-f43feacbbb5b'
+	// Note: See the [log stream ARN format
+	// documentation](https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/iam-
+	// access-control-overview-cwl.html#CWL_ARN_Format). One log group can contain
+	// several log streams, so these ARNs necessarily identify both a log group and a
+	// log stream.
+	AWSLogStreamARNsKey = attribute.Key("aws.log.stream.arns")
+)
+
+// A container instance.
+const (
+	// Container name.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry-autoconf'
+	ContainerNameKey = attribute.Key("container.name")
+	// Container ID. Usually a UUID, as for example used to [identify Docker
+	// containers](https://docs.docker.com/engine/reference/run/#container-
+	// identification). The UUID might be abbreviated.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'a3bf90e006b2'
+	ContainerIDKey = attribute.Key("container.id")
+	// The container runtime managing this container.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'docker', 'containerd', 'rkt'
+	ContainerRuntimeKey = attribute.Key("container.runtime")
+	// Name of the image the container was built on.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'gcr.io/opentelemetry/operator'
+	ContainerImageNameKey = attribute.Key("container.image.name")
+	// Container image tag.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '0.1'
+	ContainerImageTagKey = attribute.Key("container.image.tag")
+)
+
+// The software deployment.
+const (
+	// Name of the [deployment
+	// environment](https://en.wikipedia.org/wiki/Deployment_environment) (aka
+	// deployment tier).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'staging', 'production'
+	DeploymentEnvironmentKey = attribute.Key("deployment.environment")
+)
+
+// The device on which the process represented by this resource is running.
+const (
+	// A unique identifier representing the device
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '2ab2916d-a51f-4ac8-80ee-45ac31a28092'
+	// Note: The device identifier MUST only be defined using the values outlined
+	// below. This value is not an advertising identifier and MUST NOT be used as
+	// such. On iOS (Swift or Objective-C), this value MUST be equal to the [vendor id
+	// entifier](https://developer.apple.com/documentation/uikit/uidevice/1620059-iden
+	// tifierforvendor). On Android (Java or Kotlin), this value MUST be equal to the
+	// Firebase Installation ID or a globally unique UUID which is persisted across
+	// sessions in your application. More information can be found
+	// [here](https://developer.android.com/training/articles/user-data-ids) on best
+	// practices and exact implementation details. Caution should be taken when
+	// storing personal data or anything which can identify a user. GDPR and data
+	// protection laws may apply, ensure you do your own due diligence.
+	DeviceIDKey = attribute.Key("device.id")
+	// The model identifier for the device
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'iPhone3,4', 'SM-G920F'
+	// Note: It's recommended this value represents a machine readable version of the
+	// model identifier rather than the market or consumer-friendly name of the
+	// device.
+	DeviceModelIdentifierKey = attribute.Key("device.model.identifier")
+	// The marketing name for the device model
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'iPhone 6s Plus', 'Samsung Galaxy S6'
+	// Note: It's recommended this value represents a human readable version of the
+	// device model rather than a machine readable alternative.
+	DeviceModelNameKey = attribute.Key("device.model.name")
+)
+
+// A serverless instance.
+const (
+	// The name of the single function that this runtime instance executes.
+	//
+	// Type: string
+	// Required: Always
+	// Stability: stable
+	// Examples: 'my-function'
+	// Note: This is the name of the function as configured/deployed on the FaaS
+	// platform and is usually different from the name of the callback function (which
+	// may be stored in the
+	// [`code.namespace`/`code.function`](../../trace/semantic_conventions/span-
+	// general.md#source-code-attributes) span attributes).
+	FaaSNameKey = attribute.Key("faas.name")
+	// The unique ID of the single function that this runtime instance executes.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'arn:aws:lambda:us-west-2:123456789012:function:my-function'
+	// Note: Depending on the cloud provider, use:
+
+	// * **AWS Lambda:** The function
+	// [ARN](https://docs.aws.amazon.com/general/latest/gr/aws-arns-and-
+	// namespaces.html).
+	// Take care not to use the "invoked ARN" directly but replace any
+	// [alias suffix](https://docs.aws.amazon.com/lambda/latest/dg/configuration-
+	// aliases.html) with the resolved function version, as the same runtime instance
+	// may be invokable with multiple
+	// different aliases.
+	// * **GCP:** The [URI of the resource](https://cloud.google.com/iam/docs/full-
+	// resource-names)
+	// * **Azure:** The [Fully Qualified Resource ID](https://docs.microsoft.com/en-
+	// us/rest/api/resources/resources/get-by-id).
+
+	// On some providers, it may not be possible to determine the full ID at startup,
+	// which is why this field cannot be made required. For example, on AWS the
+	// account ID
+	// part of the ARN is not available without calling another AWS API
+	// which may be deemed too slow for a short-running lambda function.
+	// As an alternative, consider setting `faas.id` as a span attribute instead.
+	FaaSIDKey = attribute.Key("faas.id")
+	// The immutable version of the function being executed.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '26', 'pinkfroid-00002'
+	// Note: Depending on the cloud provider and platform, use:
+
+	// * **AWS Lambda:** The [function
+	// version](https://docs.aws.amazon.com/lambda/latest/dg/configuration-
+	// versions.html)
+	//   (an integer represented as a decimal string).
+	// * **Google Cloud Run:** The
+	// [revision](https://cloud.google.com/run/docs/managing/revisions)
+	//   (i.e., the function name plus the revision suffix).
+	// * **Google Cloud Functions:** The value of the
+	//   [`K_REVISION` environment
+	// variable](https://cloud.google.com/functions/docs/env-
+	// var#runtime_environment_variables_set_automatically).
+	// * **Azure Functions:** Not applicable. Do not set this attribute.
+	FaaSVersionKey = attribute.Key("faas.version")
+	// The execution environment ID as a string, that will be potentially reused for
+	// other invocations to the same function/function version.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '2021/06/28/[$LATEST]2f399eb14537447da05ab2a2e39309de'
+	// Note: * **AWS Lambda:** Use the (full) log stream name.
+	FaaSInstanceKey = attribute.Key("faas.instance")
+	// The amount of memory available to the serverless function in MiB.
+	//
+	// Type: int
+	// Required: No
+	// Stability: stable
+	// Examples: 128
+	// Note: It's recommended to set this attribute since e.g. too little memory can
+	// easily stop a Java AWS Lambda function from working correctly. On AWS Lambda,
+	// the environment variable `AWS_LAMBDA_FUNCTION_MEMORY_SIZE` provides this
+	// information.
+	FaaSMaxMemoryKey = attribute.Key("faas.max_memory")
+)
+
+// A host is defined as a general computing instance.
+const (
+	// Unique host ID. For Cloud, this must be the instance_id assigned by the cloud
+	// provider.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry-test'
+	HostIDKey = attribute.Key("host.id")
+	// Name of the host. On Unix systems, it may contain what the hostname command
+	// returns, or the fully qualified hostname, or another name specified by the
+	// user.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry-test'
+	HostNameKey = attribute.Key("host.name")
+	// Type of host. For Cloud, this must be the machine type.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'n1-standard-1'
+	HostTypeKey = attribute.Key("host.type")
+	// The CPU architecture the host system is running on.
+	//
+	// Type: Enum
+	// Required: No
+	// Stability: stable
+	HostArchKey = attribute.Key("host.arch")
+	// Name of the VM image or OS install the host was instantiated from.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'infra-ami-eks-worker-node-7d4ec78312', 'CentOS-8-x86_64-1905'
+	HostImageNameKey = attribute.Key("host.image.name")
+	// VM image ID. For Cloud, this value is from the provider.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'ami-07b06b442921831e5'
+	HostImageIDKey = attribute.Key("host.image.id")
+	// The version string of the VM image as defined in [Version
+	// Attributes](README.md#version-attributes).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '0.1'
+	HostImageVersionKey = attribute.Key("host.image.version")
+)
+
+var (
+	// AMD64
+	HostArchAMD64 = HostArchKey.String("amd64")
+	// ARM32
+	HostArchARM32 = HostArchKey.String("arm32")
+	// ARM64
+	HostArchARM64 = HostArchKey.String("arm64")
+	// Itanium
+	HostArchIA64 = HostArchKey.String("ia64")
+	// 32-bit PowerPC
+	HostArchPPC32 = HostArchKey.String("ppc32")
+	// 64-bit PowerPC
+	HostArchPPC64 = HostArchKey.String("ppc64")
+	// 32-bit x86
+	HostArchX86 = HostArchKey.String("x86")
+)
+
+// A Kubernetes Cluster.
+const (
+	// The name of the cluster.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry-cluster'
+	K8SClusterNameKey = attribute.Key("k8s.cluster.name")
+)
+
+// A Kubernetes Node object.
+const (
+	// The name of the Node.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'node-1'
+	K8SNodeNameKey = attribute.Key("k8s.node.name")
+	// The UID of the Node.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '1eb3a0c6-0477-4080-a9cb-0cb7db65c6a2'
+	K8SNodeUIDKey = attribute.Key("k8s.node.uid")
+)
+
+// A Kubernetes Namespace.
+const (
+	// The name of the namespace that the pod is running in.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'default'
+	K8SNamespaceNameKey = attribute.Key("k8s.namespace.name")
+)
+
+// A Kubernetes Pod object.
+const (
+	// The UID of the Pod.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SPodUIDKey = attribute.Key("k8s.pod.uid")
+	// The name of the Pod.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry-pod-autoconf'
+	K8SPodNameKey = attribute.Key("k8s.pod.name")
+)
+
+// A container in a [PodTemplate](https://kubernetes.io/docs/concepts/workloads/pods/#pod-templates).
+const (
+	// The name of the Container in a Pod template.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'redis'
+	K8SContainerNameKey = attribute.Key("k8s.container.name")
+)
+
+// A Kubernetes ReplicaSet object.
+const (
+	// The UID of the ReplicaSet.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SReplicaSetUIDKey = attribute.Key("k8s.replicaset.uid")
+	// The name of the ReplicaSet.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	K8SReplicaSetNameKey = attribute.Key("k8s.replicaset.name")
+)
+
+// A Kubernetes Deployment object.
+const (
+	// The UID of the Deployment.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SDeploymentUIDKey = attribute.Key("k8s.deployment.uid")
+	// The name of the Deployment.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	K8SDeploymentNameKey = attribute.Key("k8s.deployment.name")
+)
+
+// A Kubernetes StatefulSet object.
+const (
+	// The UID of the StatefulSet.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SStatefulSetUIDKey = attribute.Key("k8s.statefulset.uid")
+	// The name of the StatefulSet.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	K8SStatefulSetNameKey = attribute.Key("k8s.statefulset.name")
+)
+
+// A Kubernetes DaemonSet object.
+const (
+	// The UID of the DaemonSet.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SDaemonSetUIDKey = attribute.Key("k8s.daemonset.uid")
+	// The name of the DaemonSet.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	K8SDaemonSetNameKey = attribute.Key("k8s.daemonset.name")
+)
+
+// A Kubernetes Job object.
+const (
+	// The UID of the Job.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SJobUIDKey = attribute.Key("k8s.job.uid")
+	// The name of the Job.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	K8SJobNameKey = attribute.Key("k8s.job.name")
+)
+
+// A Kubernetes CronJob object.
+const (
+	// The UID of the CronJob.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '275ecb36-5aa8-4c2a-9c47-d8bb681b9aff'
+	K8SCronJobUIDKey = attribute.Key("k8s.cronjob.uid")
+	// The name of the CronJob.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	K8SCronJobNameKey = attribute.Key("k8s.cronjob.name")
+)
+
+// The operating system (OS) on which the process represented by this resource is running.
+const (
+	// The operating system type.
+	//
+	// Type: Enum
+	// Required: Always
+	// Stability: stable
+	OSTypeKey = attribute.Key("os.type")
+	// Human readable (not intended to be parsed) OS version information, like e.g.
+	// reported by `ver` or `lsb_release -a` commands.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'Microsoft Windows [Version 10.0.18363.778]', 'Ubuntu 18.04.1 LTS'
+	OSDescriptionKey = attribute.Key("os.description")
+	// Human readable operating system name.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'iOS', 'Android', 'Ubuntu'
+	OSNameKey = attribute.Key("os.name")
+	// The version string of the operating system as defined in [Version
+	// Attributes](../../resource/semantic_conventions/README.md#version-attributes).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '14.2.1', '18.04.1'
+	OSVersionKey = attribute.Key("os.version")
+)
+
+var (
+	// Microsoft Windows
+	OSTypeWindows = OSTypeKey.String("windows")
+	// Linux
+	OSTypeLinux = OSTypeKey.String("linux")
+	// Apple Darwin
+	OSTypeDarwin = OSTypeKey.String("darwin")
+	// FreeBSD
+	OSTypeFreeBSD = OSTypeKey.String("freebsd")
+	// NetBSD
+	OSTypeNetBSD = OSTypeKey.String("netbsd")
+	// OpenBSD
+	OSTypeOpenBSD = OSTypeKey.String("openbsd")
+	// DragonFly BSD
+	OSTypeDragonflyBSD = OSTypeKey.String("dragonflybsd")
+	// HP-UX (Hewlett Packard Unix)
+	OSTypeHPUX = OSTypeKey.String("hpux")
+	// AIX (Advanced Interactive eXecutive)
+	OSTypeAIX = OSTypeKey.String("aix")
+	// Oracle Solaris
+	OSTypeSolaris = OSTypeKey.String("solaris")
+	// IBM z/OS
+	OSTypeZOS = OSTypeKey.String("z_os")
+)
+
+// An operating system process.
+const (
+	// Process identifier (PID).
+	//
+	// Type: int
+	// Required: No
+	// Stability: stable
+	// Examples: 1234
+	ProcessPIDKey = attribute.Key("process.pid")
+	// The name of the process executable. On Linux based systems, can be set to the
+	// `Name` in `proc/[pid]/status`. On Windows, can be set to the base name of
+	// `GetProcessImageFileNameW`.
+	//
+	// Type: string
+	// Required: See below
+	// Stability: stable
+	// Examples: 'otelcol'
+	ProcessExecutableNameKey = attribute.Key("process.executable.name")
+	// The full path to the process executable. On Linux based systems, can be set to
+	// the target of `proc/[pid]/exe`. On Windows, can be set to the result of
+	// `GetProcessImageFileNameW`.
+	//
+	// Type: string
+	// Required: See below
+	// Stability: stable
+	// Examples: '/usr/bin/cmd/otelcol'
+	ProcessExecutablePathKey = attribute.Key("process.executable.path")
+	// The command used to launch the process (i.e. the command name). On Linux based
+	// systems, can be set to the zeroth string in `proc/[pid]/cmdline`. On Windows,
+	// can be set to the first parameter extracted from `GetCommandLineW`.
+	//
+	// Type: string
+	// Required: See below
+	// Stability: stable
+	// Examples: 'cmd/otelcol'
+	ProcessCommandKey = attribute.Key("process.command")
+	// The full command used to launch the process as a single string representing the
+	// full command. On Windows, can be set to the result of `GetCommandLineW`. Do not
+	// set this if you have to assemble it just for monitoring; use
+	// `process.command_args` instead.
+	//
+	// Type: string
+	// Required: See below
+	// Stability: stable
+	// Examples: 'C:\\cmd\\otecol --config="my directory\\config.yaml"'
+	ProcessCommandLineKey = attribute.Key("process.command_line")
+	// All the command arguments (including the command/executable itself) as received
+	// by the process. On Linux-based systems (and some other Unixoid systems
+	// supporting procfs), can be set according to the list of null-delimited strings
+	// extracted from `proc/[pid]/cmdline`. For libc-based executables, this would be
+	// the full argv vector passed to `main`.
+	//
+	// Type: string[]
+	// Required: See below
+	// Stability: stable
+	// Examples: 'cmd/otecol', '--config=config.yaml'
+	ProcessCommandArgsKey = attribute.Key("process.command_args")
+	// The username of the user that owns the process.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'root'
+	ProcessOwnerKey = attribute.Key("process.owner")
+)
+
+// The single (language) runtime instance which is monitored.
+const (
+	// The name of the runtime of this process. For compiled native binaries, this
+	// SHOULD be the name of the compiler.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'OpenJDK Runtime Environment'
+	ProcessRuntimeNameKey = attribute.Key("process.runtime.name")
+	// The version of the runtime of this process, as returned by the runtime without
+	// modification.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '14.0.2'
+	ProcessRuntimeVersionKey = attribute.Key("process.runtime.version")
+	// An additional description about the runtime of the process, for example a
+	// specific vendor customization of the runtime environment.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'Eclipse OpenJ9 Eclipse OpenJ9 VM openj9-0.21.0'
+	ProcessRuntimeDescriptionKey = attribute.Key("process.runtime.description")
+)
+
+// A service instance.
+const (
+	// Logical name of the service.
+	//
+	// Type: string
+	// Required: Always
+	// Stability: stable
+	// Examples: 'shoppingcart'
+	// Note: MUST be the same for all instances of horizontally scaled services. If
+	// the value was not specified, SDKs MUST fallback to `unknown_service:`
+	// concatenated with [`process.executable.name`](process.md#process), e.g.
+	// `unknown_service:bash`. If `process.executable.name` is not available, the
+	// value MUST be set to `unknown_service`.
+	ServiceNameKey = attribute.Key("service.name")
+	// A namespace for `service.name`.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'Shop'
+	// Note: A string value having a meaning that helps to distinguish a group of
+	// services, for example the team name that owns a group of services.
+	// `service.name` is expected to be unique within the same namespace. If
+	// `service.namespace` is not specified in the Resource then `service.name` is
+	// expected to be unique for all services that have no explicit namespace defined
+	// (so the empty/unspecified namespace is simply one more valid namespace). Zero-
+	// length namespace string is assumed equal to unspecified namespace.
+	ServiceNamespaceKey = attribute.Key("service.namespace")
+	// The string ID of the service instance.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '627cc493-f310-47de-96bd-71410b7dec09'
+	// Note: MUST be unique for each instance of the same
+	// `service.namespace,service.name` pair (in other words
+	// `service.namespace,service.name,service.instance.id` triplet MUST be globally
+	// unique). The ID helps to distinguish instances of the same service that exist
+	// at the same time (e.g. instances of a horizontally scaled service). It is
+	// preferable for the ID to be persistent and stay the same for the lifetime of
+	// the service instance, however it is acceptable that the ID is ephemeral and
+	// changes during important lifetime events for the service (e.g. service
+	// restarts). If the service has no inherent unique ID that can be used as the
+	// value of this attribute it is recommended to generate a random Version 1 or
+	// Version 4 RFC 4122 UUID (services aiming for reproducible UUIDs may also use
+	// Version 5, see RFC 4122 for more recommendations).
+	ServiceInstanceIDKey = attribute.Key("service.instance.id")
+	// The version string of the service API or implementation.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '2.0.0'
+	ServiceVersionKey = attribute.Key("service.version")
+)
+
+// The telemetry SDK used to capture data recorded by the instrumentation libraries.
+const (
+	// The name of the telemetry SDK as defined above.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'opentelemetry'
+	TelemetrySDKNameKey = attribute.Key("telemetry.sdk.name")
+	// The language of the telemetry SDK.
+	//
+	// Type: Enum
+	// Required: No
+	// Stability: stable
+	TelemetrySDKLanguageKey = attribute.Key("telemetry.sdk.language")
+	// The version string of the telemetry SDK.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '1.2.3'
+	TelemetrySDKVersionKey = attribute.Key("telemetry.sdk.version")
+	// The version string of the auto instrumentation agent, if used.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '1.2.3'
+	TelemetryAutoVersionKey = attribute.Key("telemetry.auto.version")
+)
+
+var (
+	// cpp
+	TelemetrySDKLanguageCPP = TelemetrySDKLanguageKey.String("cpp")
+	// dotnet
+	TelemetrySDKLanguageDotnet = TelemetrySDKLanguageKey.String("dotnet")
+	// erlang
+	TelemetrySDKLanguageErlang = TelemetrySDKLanguageKey.String("erlang")
+	// go
+	TelemetrySDKLanguageGo = TelemetrySDKLanguageKey.String("go")
+	// java
+	TelemetrySDKLanguageJava = TelemetrySDKLanguageKey.String("java")
+	// nodejs
+	TelemetrySDKLanguageNodejs = TelemetrySDKLanguageKey.String("nodejs")
+	// php
+	TelemetrySDKLanguagePHP = TelemetrySDKLanguageKey.String("php")
+	// python
+	TelemetrySDKLanguagePython = TelemetrySDKLanguageKey.String("python")
+	// ruby
+	TelemetrySDKLanguageRuby = TelemetrySDKLanguageKey.String("ruby")
+	// webjs
+	TelemetrySDKLanguageWebjs = TelemetrySDKLanguageKey.String("webjs")
+)
+
+// Resource describing the packaged software running the application code. Web engines are typically executed using process.runtime.
+const (
+	// The name of the web engine.
+	//
+	// Type: string
+	// Required: Always
+	// Stability: stable
+	// Examples: 'WildFly'
+	WebEngineNameKey = attribute.Key("webengine.name")
+	// The version of the web engine.
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: '21.0.0'
+	WebEngineVersionKey = attribute.Key("webengine.version")
+	// Additional description of the web engine (e.g. detailed version and edition
+	// information).
+	//
+	// Type: string
+	// Required: No
+	// Stability: stable
+	// Examples: 'WildFly Full 21.0.0.Final (WildFly Core 13.0.1.Final) - 2.2.2.Final'
+	WebEngineDescriptionKey = attribute.Key("webengine.description")
+)

vendor/go.opentelemetry.io/otel/semconv/v1.7.0/schema.go

@@ -0,0 +1,20 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package semconv // import "go.opentelemetry.io/otel/semconv/v1.7.0"
+
+// SchemaURL is the schema URL that matches the version of the semantic conventions
+// that this package defines. Semconv packages starting from v1.4.0 must declare
+// non-empty schema URL in the form https://opentelemetry.io/schemas/<version>
+const SchemaURL = "https://opentelemetry.io/schemas/1.7.0"

vendor/go.opentelemetry.io/otel/trace.go

@@ -0,0 +1,44 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otel // import "go.opentelemetry.io/otel"
+
+import (
+	"go.opentelemetry.io/otel/internal/global"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// Tracer creates a named tracer that implements Tracer interface.
+// If the name is an empty string then provider uses default name.
+//
+// This is short for GetTracerProvider().Tracer(name, opts...)
+func Tracer(name string, opts ...trace.TracerOption) trace.Tracer {
+	return GetTracerProvider().Tracer(name, opts...)
+}
+
+// GetTracerProvider returns the registered global trace provider.
+// If none is registered then an instance of NoopTracerProvider is returned.
+//
+// Use the trace provider to create a named tracer. E.g.
+//     tracer := otel.GetTracerProvider().Tracer("example.com/foo")
+// or
+//     tracer := otel.Tracer("example.com/foo")
+func GetTracerProvider() trace.TracerProvider {
+	return global.TracerProvider()
+}
+
+// SetTracerProvider registers `tp` as the global trace provider.
+func SetTracerProvider(tp trace.TracerProvider) {
+	global.SetTracerProvider(tp)
+}

vendor/go.opentelemetry.io/otel/trace/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
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+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
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+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
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+      of this License, Derivative Works shall not include works that remain
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+      "Contribution" shall mean any work of authorship, including
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+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
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+
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+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
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+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+          notices within Derivative Works that You distribute, alongside
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+
+      You may add Your own copyright statement to Your modifications and
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+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
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+      Work (including but not limited to damages for loss of goodwill,
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+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
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+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
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+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/go.opentelemetry.io/otel/trace/config.go

@@ -0,0 +1,316 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/trace"
+
+import (
+	"time"
+
+	"go.opentelemetry.io/otel/attribute"
+)
+
+// TracerConfig is a group of options for a Tracer.
+type TracerConfig struct {
+	instrumentationVersion string
+	// Schema URL of the telemetry emitted by the Tracer.
+	schemaURL string
+}
+
+// InstrumentationVersion returns the version of the library providing instrumentation.
+func (t *TracerConfig) InstrumentationVersion() string {
+	return t.instrumentationVersion
+}
+
+// SchemaURL returns the Schema URL of the telemetry emitted by the Tracer.
+func (t *TracerConfig) SchemaURL() string {
+	return t.schemaURL
+}
+
+// NewTracerConfig applies all the options to a returned TracerConfig.
+func NewTracerConfig(options ...TracerOption) TracerConfig {
+	var config TracerConfig
+	for _, option := range options {
+		config = option.apply(config)
+	}
+	return config
+}
+
+// TracerOption applies an option to a TracerConfig.
+type TracerOption interface {
+	apply(TracerConfig) TracerConfig
+}
+
+type tracerOptionFunc func(TracerConfig) TracerConfig
+
+func (fn tracerOptionFunc) apply(cfg TracerConfig) TracerConfig {
+	return fn(cfg)
+}
+
+// SpanConfig is a group of options for a Span.
+type SpanConfig struct {
+	attributes []attribute.KeyValue
+	timestamp  time.Time
+	links      []Link
+	newRoot    bool
+	spanKind   SpanKind
+	stackTrace bool
+}
+
+// Attributes describe the associated qualities of a Span.
+func (cfg *SpanConfig) Attributes() []attribute.KeyValue {
+	return cfg.attributes
+}
+
+// Timestamp is a time in a Span life-cycle.
+func (cfg *SpanConfig) Timestamp() time.Time {
+	return cfg.timestamp
+}
+
+// StackTrace checks whether stack trace capturing is enabled.
+func (cfg *SpanConfig) StackTrace() bool {
+	return cfg.stackTrace
+}
+
+// Links are the associations a Span has with other Spans.
+func (cfg *SpanConfig) Links() []Link {
+	return cfg.links
+}
+
+// NewRoot identifies a Span as the root Span for a new trace. This is
+// commonly used when an existing trace crosses trust boundaries and the
+// remote parent span context should be ignored for security.
+func (cfg *SpanConfig) NewRoot() bool {
+	return cfg.newRoot
+}
+
+// SpanKind is the role a Span has in a trace.
+func (cfg *SpanConfig) SpanKind() SpanKind {
+	return cfg.spanKind
+}
+
+// NewSpanStartConfig applies all the options to a returned SpanConfig.
+// No validation is performed on the returned SpanConfig (e.g. no uniqueness
+// checking or bounding of data), it is left to the SDK to perform this
+// action.
+func NewSpanStartConfig(options ...SpanStartOption) SpanConfig {
+	var c SpanConfig
+	for _, option := range options {
+		c = option.applySpanStart(c)
+	}
+	return c
+}
+
+// NewSpanEndConfig applies all the options to a returned SpanConfig.
+// No validation is performed on the returned SpanConfig (e.g. no uniqueness
+// checking or bounding of data), it is left to the SDK to perform this
+// action.
+func NewSpanEndConfig(options ...SpanEndOption) SpanConfig {
+	var c SpanConfig
+	for _, option := range options {
+		c = option.applySpanEnd(c)
+	}
+	return c
+}
+
+// SpanStartOption applies an option to a SpanConfig. These options are applicable
+// only when the span is created
+type SpanStartOption interface {
+	applySpanStart(SpanConfig) SpanConfig
+}
+
+type spanOptionFunc func(SpanConfig) SpanConfig
+
+func (fn spanOptionFunc) applySpanStart(cfg SpanConfig) SpanConfig {
+	return fn(cfg)
+}
+
+// SpanEndOption applies an option to a SpanConfig. These options are
+// applicable only when the span is ended.
+type SpanEndOption interface {
+	applySpanEnd(SpanConfig) SpanConfig
+}
+
+// EventConfig is a group of options for an Event.
+type EventConfig struct {
+	attributes []attribute.KeyValue
+	timestamp  time.Time
+	stackTrace bool
+}
+
+// Attributes describe the associated qualities of an Event.
+func (cfg *EventConfig) Attributes() []attribute.KeyValue {
+	return cfg.attributes
+}
+
+// Timestamp is a time in an Event life-cycle.
+func (cfg *EventConfig) Timestamp() time.Time {
+	return cfg.timestamp
+}
+
+// StackTrace checks whether stack trace capturing is enabled.
+func (cfg *EventConfig) StackTrace() bool {
+	return cfg.stackTrace
+}
+
+// NewEventConfig applies all the EventOptions to a returned EventConfig. If no
+// timestamp option is passed, the returned EventConfig will have a Timestamp
+// set to the call time, otherwise no validation is performed on the returned
+// EventConfig.
+func NewEventConfig(options ...EventOption) EventConfig {
+	var c EventConfig
+	for _, option := range options {
+		c = option.applyEvent(c)
+	}
+	if c.timestamp.IsZero() {
+		c.timestamp = time.Now()
+	}
+	return c
+}
+
+// EventOption applies span event options to an EventConfig.
+type EventOption interface {
+	applyEvent(EventConfig) EventConfig
+}
+
+// SpanOption are options that can be used at both the beginning and end of a span.
+type SpanOption interface {
+	SpanStartOption
+	SpanEndOption
+}
+
+// SpanStartEventOption are options that can be used at the start of a span, or with an event.
+type SpanStartEventOption interface {
+	SpanStartOption
+	EventOption
+}
+
+// SpanEndEventOption are options that can be used at the end of a span, or with an event.
+type SpanEndEventOption interface {
+	SpanEndOption
+	EventOption
+}
+
+type attributeOption []attribute.KeyValue
+
+func (o attributeOption) applySpan(c SpanConfig) SpanConfig {
+	c.attributes = append(c.attributes, []attribute.KeyValue(o)...)
+	return c
+}
+func (o attributeOption) applySpanStart(c SpanConfig) SpanConfig { return o.applySpan(c) }
+func (o attributeOption) applyEvent(c EventConfig) EventConfig {
+	c.attributes = append(c.attributes, []attribute.KeyValue(o)...)
+	return c
+}
+
+var _ SpanStartEventOption = attributeOption{}
+
+// WithAttributes adds the attributes related to a span life-cycle event.
+// These attributes are used to describe the work a Span represents when this
+// option is provided to a Span's start or end events. Otherwise, these
+// attributes provide additional information about the event being recorded
+// (e.g. error, state change, processing progress, system event).
+//
+// If multiple of these options are passed the attributes of each successive
+// option will extend the attributes instead of overwriting. There is no
+// guarantee of uniqueness in the resulting attributes.
+func WithAttributes(attributes ...attribute.KeyValue) SpanStartEventOption {
+	return attributeOption(attributes)
+}
+
+// SpanEventOption are options that can be used with an event or a span.
+type SpanEventOption interface {
+	SpanOption
+	EventOption
+}
+
+type timestampOption time.Time
+
+func (o timestampOption) applySpan(c SpanConfig) SpanConfig {
+	c.timestamp = time.Time(o)
+	return c
+}
+func (o timestampOption) applySpanStart(c SpanConfig) SpanConfig { return o.applySpan(c) }
+func (o timestampOption) applySpanEnd(c SpanConfig) SpanConfig   { return o.applySpan(c) }
+func (o timestampOption) applyEvent(c EventConfig) EventConfig {
+	c.timestamp = time.Time(o)
+	return c
+}
+
+var _ SpanEventOption = timestampOption{}
+
+// WithTimestamp sets the time of a Span or Event life-cycle moment (e.g.
+// started, stopped, errored).
+func WithTimestamp(t time.Time) SpanEventOption {
+	return timestampOption(t)
+}
+
+type stackTraceOption bool
+
+func (o stackTraceOption) applyEvent(c EventConfig) EventConfig {
+	c.stackTrace = bool(o)
+	return c
+}
+func (o stackTraceOption) applySpan(c SpanConfig) SpanConfig {
+	c.stackTrace = bool(o)
+	return c
+}
+func (o stackTraceOption) applySpanEnd(c SpanConfig) SpanConfig { return o.applySpan(c) }
+
+// WithStackTrace sets the flag to capture the error with stack trace (e.g. true, false).
+func WithStackTrace(b bool) SpanEndEventOption {
+	return stackTraceOption(b)
+}
+
+// WithLinks adds links to a Span. The links are added to the existing Span
+// links, i.e. this does not overwrite. Links with invalid span context are ignored.
+func WithLinks(links ...Link) SpanStartOption {
+	return spanOptionFunc(func(cfg SpanConfig) SpanConfig {
+		cfg.links = append(cfg.links, links...)
+		return cfg
+	})
+}
+
+// WithNewRoot specifies that the Span should be treated as a root Span. Any
+// existing parent span context will be ignored when defining the Span's trace
+// identifiers.
+func WithNewRoot() SpanStartOption {
+	return spanOptionFunc(func(cfg SpanConfig) SpanConfig {
+		cfg.newRoot = true
+		return cfg
+	})
+}
+
+// WithSpanKind sets the SpanKind of a Span.
+func WithSpanKind(kind SpanKind) SpanStartOption {
+	return spanOptionFunc(func(cfg SpanConfig) SpanConfig {
+		cfg.spanKind = kind
+		return cfg
+	})
+}
+
+// WithInstrumentationVersion sets the instrumentation version.
+func WithInstrumentationVersion(version string) TracerOption {
+	return tracerOptionFunc(func(cfg TracerConfig) TracerConfig {
+		cfg.instrumentationVersion = version
+		return cfg
+	})
+}
+
+// WithSchemaURL sets the schema URL for the Tracer.
+func WithSchemaURL(schemaURL string) TracerOption {
+	return tracerOptionFunc(func(cfg TracerConfig) TracerConfig {
+		cfg.schemaURL = schemaURL
+		return cfg
+	})
+}

vendor/go.opentelemetry.io/otel/trace/context.go

@@ -0,0 +1,61 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace // import "go.opentelemetry.io/otel/trace"
+
+import "context"
+
+type traceContextKeyType int
+
+const currentSpanKey traceContextKeyType = iota
+
+// ContextWithSpan returns a copy of parent with span set as the current Span.
+func ContextWithSpan(parent context.Context, span Span) context.Context {
+	return context.WithValue(parent, currentSpanKey, span)
+}
+
+// ContextWithSpanContext returns a copy of parent with sc as the current
+// Span. The Span implementation that wraps sc is non-recording and performs
+// no operations other than to return sc as the SpanContext from the
+// SpanContext method.
+func ContextWithSpanContext(parent context.Context, sc SpanContext) context.Context {
+	return ContextWithSpan(parent, nonRecordingSpan{sc: sc})
+}
+
+// ContextWithRemoteSpanContext returns a copy of parent with rsc set explicly
+// as a remote SpanContext and as the current Span. The Span implementation
+// that wraps rsc is non-recording and performs no operations other than to
+// return rsc as the SpanContext from the SpanContext method.
+func ContextWithRemoteSpanContext(parent context.Context, rsc SpanContext) context.Context {
+	return ContextWithSpanContext(parent, rsc.WithRemote(true))
+}
+
+// SpanFromContext returns the current Span from ctx.
+//
+// If no Span is currently set in ctx an implementation of a Span that
+// performs no operations is returned.
+func SpanFromContext(ctx context.Context) Span {
+	if ctx == nil {
+		return noopSpan{}
+	}
+	if span, ok := ctx.Value(currentSpanKey).(Span); ok {
+		return span
+	}
+	return noopSpan{}
+}
+
+// SpanContextFromContext returns the current Span's SpanContext.
+func SpanContextFromContext(ctx context.Context) SpanContext {
+	return SpanFromContext(ctx).SpanContext()
+}