TUN-6030: Add ttfb span for origin http request

tracing/tracing.go

@@ -3,7 +3,10 @@ package tracing
 import (
 	"context"
 	"errors"
+	"fmt"
 	"net/http"
+	"os"
+	"runtime"
 
 	"github.com/rs/zerolog"
 	otelContrib "go.opentelemetry.io/contrib/propagators/Jaeger"
@@ -22,19 +25,26 @@ const (
 	service              = "cloudflared"
 	tracerInstrumentName = "origin"
 
-	tracerContextName         = "cf-trace-id"
-	tracerContextNameOverride = "uber-trace-id"
+	TracerContextName         = "cf-trace-id"
+	TracerContextNameOverride = "uber-trace-id"
 
 	IntCloudflaredTracingHeader = "cf-int-cloudflared-tracing"
 )
 
 var (
 	CanonicalCloudflaredTracingHeader = http.CanonicalHeaderKey(IntCloudflaredTracingHeader)
-	Http2TransportAttribute           = trace.WithAttributes(TransportAttributeKey.String("http2"))
-	QuicTransportAttribute            = trace.WithAttributes(TransportAttributeKey.String("quic"))
+	Http2TransportAttribute           = trace.WithAttributes(transportAttributeKey.String("http2"))
+	QuicTransportAttribute            = trace.WithAttributes(transportAttributeKey.String("quic"))
+	HostOSAttribute                   = semconv.HostTypeKey.String(runtime.GOOS)
+	HostArchAttribute                 = semconv.HostArchKey.String(runtime.GOARCH)
 
-	TransportAttributeKey = attribute.Key("transport")
-	TrafficAttributeKey   = attribute.Key("traffic")
+	otelVersionAttribute        attribute.KeyValue
+	hostnameAttribute           attribute.KeyValue
+	cloudflaredVersionAttribute attribute.KeyValue
+	serviceAttribute            = semconv.ServiceNameKey.String(service)
+
+	transportAttributeKey   = attribute.Key("transport")
+	otelVersionAttributeKey = attribute.Key("jaeger.version")
 
 	errNoopTracerProvider = errors.New("noop tracer provider records no spans")
 )
@@ -42,6 +52,14 @@ var (
 func init() {
 	// Register the jaeger propagator globally.
 	otel.SetTextMapPropagator(otelContrib.Jaeger{})
+	otelVersionAttribute = otelVersionAttributeKey.String(fmt.Sprintf("go-otel-%s", otel.Version()))
+	if hostname, err := os.Hostname(); err == nil {
+		hostnameAttribute = attribute.String("hostname", hostname)
+	}
+}
+
+func Init(version string) {
+	cloudflaredVersionAttribute = semconv.ProcessRuntimeVersionKey.String(version)
 }
 
 type TracedRequest struct {
@@ -67,7 +85,12 @@ func NewTracedRequest(req *http.Request) *TracedRequest {
 		// Record information about this application in a Resource.
 		tracesdk.WithResource(resource.NewWithAttributes(
 			semconv.SchemaURL,
-			semconv.ServiceNameKey.String(service),
+			serviceAttribute,
+			otelVersionAttribute,
+			hostnameAttribute,
+			cloudflaredVersionAttribute,
+			HostOSAttribute,
+			HostArchAttribute,
 		)),
 	)
 
@@ -110,27 +133,28 @@ func EndWithStatus(span trace.Span, code codes.Code, status string) {
 	span.End()
 }
 
-// extractTrace attempts to check for a cf-trace-id from a request header.
+// extractTrace attempts to check for a cf-trace-id from a request and return the
+// trace context with the provided http.Request.
 func extractTrace(req *http.Request) (context.Context, bool) {
 	// Only add tracing for requests with appropriately tagged headers
-	remoteTraces := req.Header.Values(tracerContextName)
+	remoteTraces := req.Header.Values(TracerContextName)
 	if len(remoteTraces) <= 0 {
 		// Strip the cf-trace-id header
-		req.Header.Del(tracerContextName)
+		req.Header.Del(TracerContextName)
 		return nil, false
 	}
 
-	traceHeader := make(map[string]string, 1)
+	traceHeader := map[string]string{}
 	for _, t := range remoteTraces {
 		// Override the 'cf-trace-id' as 'uber-trace-id' so the jaeger propagator can extract it.
 		// Last entry wins if multiple provided
-		traceHeader[tracerContextNameOverride] = t
+		traceHeader[TracerContextNameOverride] = t
 	}
 
 	// Strip the cf-trace-id header
-	req.Header.Del(tracerContextName)
+	req.Header.Del(TracerContextName)
 
-	if traceHeader[tracerContextNameOverride] == "" {
+	if traceHeader[TracerContextNameOverride] == "" {
 		return nil, false
 	}
 	remoteCtx := otel.GetTextMapPropagator().Extract(req.Context(), propagation.MapCarrier(traceHeader))