TUN-2607: add RPC stream helpers

connection/connection.go

@@ -4,15 +4,12 @@ import (
 	"context"
 	"time"
 
-	"github.com/cloudflare/cloudflared/h2mux"
-	"github.com/cloudflare/cloudflared/tunnelrpc"
-	"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
-	tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
 	"github.com/google/uuid"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 
-	rpc "zombiezen.com/go/capnproto2/rpc"
+	"github.com/cloudflare/cloudflared/h2mux"
+	tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
 )
 
 const (
@@ -41,32 +38,15 @@ func (c *Connection) Serve(ctx context.Context) error {
 }
 
 // Connect is used to establish connections with cloudflare's edge network
-func (c *Connection) Connect(ctx context.Context, parameters *tunnelpogs.ConnectParameters, logger *logrus.Entry) (pogs.ConnectResult, error) {
-	openStreamCtx, cancel := context.WithTimeout(ctx, openStreamTimeout)
-	defer cancel()
-
-	rpcConn, err := c.newRPConn(openStreamCtx, logger)
+func (c *Connection) Connect(ctx context.Context, parameters *tunnelpogs.ConnectParameters, logger *logrus.Entry) (tunnelpogs.ConnectResult, error) {
+	tsClient, err := NewRPCClient(ctx, c.muxer, logger.WithField("rpc", "connect"), openStreamTimeout)
 	if err != nil {
 		return nil, errors.Wrap(err, "cannot create new RPC connection")
 	}
-	defer rpcConn.Close()
-
-	tsClient := tunnelpogs.TunnelServer_PogsClient{Client: rpcConn.Bootstrap(ctx)}
-
+	defer tsClient.Close()
 	return tsClient.Connect(ctx, parameters)
 }
 
 func (c *Connection) Shutdown() {
 	c.muxer.Shutdown()
 }
-
-func (c *Connection) newRPConn(ctx context.Context, logger *logrus.Entry) (*rpc.Conn, error) {
-	stream, err := c.muxer.OpenRPCStream(ctx)
-	if err != nil {
-		return nil, err
-	}
-	return rpc.NewConn(
-		tunnelrpc.NewTransportLogger(logger.WithField("rpc", "connect"), rpc.StreamTransport(stream)),
-		tunnelrpc.ConnLog(logger.WithField("rpc", "connect")),
-	), nil
-}

connection/manager.go

@@ -7,15 +7,15 @@ import (
 	"sync"
 	"time"
 
+	"github.com/google/uuid"
+	"github.com/pkg/errors"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/sirupsen/logrus"
+
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
 	"github.com/cloudflare/cloudflared/h2mux"
 	"github.com/cloudflare/cloudflared/streamhandler"
-	"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
-	"github.com/prometheus/client_golang/prometheus"
-
-	"github.com/google/uuid"
-	"github.com/pkg/errors"
-	"github.com/sirupsen/logrus"
+	tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
 )
 
 const (
@@ -58,12 +58,12 @@ func newMetrics(namespace, subsystem string) *metrics {
 // EdgeManagerConfigurable is the configurable attributes of a EdgeConnectionManager
 type EdgeManagerConfigurable struct {
 	TunnelHostnames []h2mux.TunnelHostname
-	*pogs.EdgeConnectionConfig
+	*tunnelpogs.EdgeConnectionConfig
 }
 
 type CloudflaredConfig struct {
 	CloudflaredID uuid.UUID
-	Tags          []pogs.Tag
+	Tags          []tunnelpogs.Tag
 	BuildInfo     *buildinfo.BuildInfo
 	IntentLabel   string
 }
@@ -126,7 +126,7 @@ func (em *EdgeManager) UpdateConfigurable(newConfigurable *EdgeManagerConfigurab
 	em.state.updateConfigurable(newConfigurable)
 }
 
-func (em *EdgeManager) newConnection(ctx context.Context) *pogs.ConnectError {
+func (em *EdgeManager) newConnection(ctx context.Context) *tunnelpogs.ConnectError {
 	edgeTCPAddr := em.serviceDiscoverer.Addr()
 	configurable := em.state.getConfigurable()
 	edgeConn, err := DialEdge(ctx, configurable.Timeout, em.tlsConfig, edgeTCPAddr)
@@ -154,7 +154,7 @@ func (em *EdgeManager) newConnection(ctx context.Context) *pogs.ConnectError {
 
 	go em.serveConn(ctx, h2muxConn)
 
-	connResult, err := h2muxConn.Connect(ctx, &pogs.ConnectParameters{
+	connResult, err := h2muxConn.Connect(ctx, &tunnelpogs.ConnectParameters{
 		CloudflaredID:       em.cloudflaredConfig.CloudflaredID,
 		CloudflaredVersion:  em.cloudflaredConfig.BuildInfo.CloudflaredVersion,
 		NumPreviousAttempts: 0,
@@ -285,8 +285,8 @@ func (ems *edgeManagerState) getUserCredential() []byte {
 	return ems.userCredential
 }
 
-func retryConnection(cause string) *pogs.ConnectError {
-	return &pogs.ConnectError{
+func retryConnection(cause string) *tunnelpogs.ConnectError {
+	return &tunnelpogs.ConnectError{
 		Cause:       cause,
 		RetryAfter:  defaultRetryAfter,
 		ShouldRetry: true,

connection/manager_test.go

@@ -4,15 +4,15 @@ import (
 	"testing"
 	"time"
 
-	"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
+	"github.com/google/uuid"
+	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
 
+
+	"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
 	"github.com/cloudflare/cloudflared/h2mux"
 	"github.com/cloudflare/cloudflared/streamhandler"
 	"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
-
-	"github.com/google/uuid"
-	"github.com/sirupsen/logrus"
 )
 
 var (

connection/rpc.go

@@ -0,0 +1,49 @@
+package connection
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/sirupsen/logrus"
+	rpc "zombiezen.com/go/capnproto2/rpc"
+
+	"github.com/cloudflare/cloudflared/h2mux"
+	"github.com/cloudflare/cloudflared/tunnelrpc"
+	tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
+)
+
+// NewRPCClient creates and returns a new RPC client, which will communicate
+// using a stream on the given muxer
+func NewRPCClient(
+	ctx context.Context,
+	muxer *h2mux.Muxer,
+	logger *logrus.Entry,
+	openStreamTimeout time.Duration,
+) (client tunnelpogs.TunnelServer_PogsClient, err error) {
+	openStreamCtx, openStreamCancel := context.WithTimeout(ctx, openStreamTimeout)
+	defer openStreamCancel()
+	stream, err := muxer.OpenRPCStream(openStreamCtx)
+	if err != nil {
+		return
+	}
+
+	if !isRPCStreamResponse(stream.Headers) {
+		stream.Close()
+		err = fmt.Errorf("rpc: bad response headers: %v", stream.Headers)
+		return
+	}
+
+	conn := rpc.NewConn(
+		tunnelrpc.NewTransportLogger(logger, rpc.StreamTransport(stream)),
+		tunnelrpc.ConnLog(logger),
+	)
+	client = tunnelpogs.TunnelServer_PogsClient{Client: conn.Bootstrap(ctx), Conn: conn}
+	return client, nil
+}
+
+func isRPCStreamResponse(headers []h2mux.Header) bool {
+	return len(headers) == 1 &&
+		headers[0].Name == ":status" &&
+		headers[0].Value == "200"
+}