attach a tracing ID to the session context

client.go

@@ -37,8 +37,9 @@ type client struct {
 
 	session quicSession
 
-	tracer logging.ConnectionTracer
+	tracer    logging.ConnectionTracer
-	logger utils.Logger
+	tracingID uint64
+	logger    utils.Logger
 }
 
 var (
@@ -208,6 +209,7 @@ func dialContext(
 	if c.tracer != nil {
 		c.tracer.StartedConnection(c.conn.LocalAddr(), c.conn.RemoteAddr(), c.srcConnID, c.destConnID)
 	}
+	c.tracingID = nextSessionTracingID()
 	if err := c.dial(ctx); err != nil {
 		return nil, err
 	}
@@ -285,6 +287,7 @@ func (c *client) dial(ctx context.Context) error {
 		c.use0RTT,
 		c.hasNegotiatedVersion,
 		c.tracer,
+		c.tracingID,
 		c.logger,
 		c.version,
 	)

client_test.go

@@ -42,6 +42,7 @@ var _ = Describe("Client", func() {
 			enable0RTT bool,
 			hasNegotiatedVersion bool,
 			tracer logging.ConnectionTracer,
+			tracingID uint64,
 			logger utils.Logger,
 			v protocol.VersionNumber,
 		) quicSession
@@ -129,6 +130,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -161,6 +163,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -193,6 +196,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -231,6 +235,7 @@ var _ = Describe("Client", func() {
 				enable0RTT bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -273,6 +278,7 @@ var _ = Describe("Client", func() {
 				enable0RTT bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -320,6 +326,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -362,6 +369,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -413,6 +421,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -532,6 +541,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				versionP protocol.VersionNumber,
 			) quicSession {
@@ -571,6 +581,7 @@ var _ = Describe("Client", func() {
 				_ bool,
 				hasNegotiatedVersion bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				versionP protocol.VersionNumber,
 			) quicSession {

interface.go

@@ -75,6 +75,13 @@ type ErrorCode = protocol.ApplicationErrorCode
 // when the server rejects a 0-RTT connection attempt.
 var Err0RTTRejected = errors.New("0-RTT rejected")
 
+// SessionTracingKey can be used to associate a ConnectionTracer with a Session.
+// It is set on the Session.Context() context,
+// as well as on the context passed to logging.Tracer.NewConnectionTracer.
+var SessionTracingKey = sessionTracingCtxKey{}
+
+type sessionTracingCtxKey struct{}
+
 // Stream is the interface implemented by QUIC streams
 type Stream interface {
 	ReceiveStream

server.go

@@ -87,6 +87,7 @@ type baseServer struct {
 		*handshake.TokenGenerator,
 		bool, /* enable 0-RTT */
 		logging.ConnectionTracer,
+		uint64,
 		utils.Logger,
 		protocol.VersionNumber,
 	) quicSession
@@ -474,6 +475,7 @@ func (s *baseServer) handleInitialImpl(p *receivedPacket, hdr *wire.Header) erro
 			s.tokenGenerator,
 			s.acceptEarlySessions,
 			tracer,
+			nextSessionTracingID(),
 			s.logger,
 			hdr.Version,
 		)

server_test.go

@@ -338,6 +338,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					enable0RTT bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -595,6 +596,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					enable0RTT bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -654,6 +656,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					_ bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -707,6 +710,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					_ bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -737,6 +741,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					_ bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -808,6 +813,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					_ bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -919,6 +925,7 @@ var _ = Describe("Server", func() {
 					_ *handshake.TokenGenerator,
 					_ bool,
 					_ logging.ConnectionTracer,
+					_ uint64,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -992,6 +999,7 @@ var _ = Describe("Server", func() {
 				_ *handshake.TokenGenerator,
 				enable0RTT bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -1034,6 +1042,7 @@ var _ = Describe("Server", func() {
 				_ *handshake.TokenGenerator,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -1097,6 +1106,7 @@ var _ = Describe("Server", func() {
 				_ *handshake.TokenGenerator,
 				_ bool,
 				_ logging.ConnectionTracer,
+				_ uint64,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {

session.go

@@ -10,6 +10,7 @@ import (
 	"net"
 	"reflect"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/lucas-clemente/quic-go/internal/ackhandler"
@@ -140,6 +141,9 @@ func (e errVersionNegotiation) Error() string {
 	return fmt.Sprintf("no compatible QUIC version found (we support %s, server offered %s)", e.ourVersions, e.theirVersions)
 }
 
+var sessionTracingID uint64        // to be accessed atomically
+func nextSessionTracingID() uint64 { return atomic.AddUint64(&sessionTracingID, 1) }
+
 // A Session is a QUIC session
 type session struct {
 	// Destination connection ID used during the handshake.
@@ -252,6 +256,7 @@ var newSession = func(
 	tokenGenerator *handshake.TokenGenerator,
 	enable0RTT bool,
 	tracer logging.ConnectionTracer,
+	tracingID uint64,
 	logger utils.Logger,
 	v protocol.VersionNumber,
 ) quicSession {
@@ -291,6 +296,7 @@ var newSession = func(
 		s.version,
 	)
 	s.preSetup()
+	s.ctx, s.ctxCancel = context.WithCancel(context.WithValue(context.Background(), SessionTracingKey, tracingID))
 	s.sentPacketHandler, s.receivedPacketHandler = ackhandler.NewAckHandler(
 		0,
 		getMaxPacketSize(s.conn.RemoteAddr()),
@@ -381,6 +387,7 @@ var newClientSession = func(
 	enable0RTT bool,
 	hasNegotiatedVersion bool,
 	tracer logging.ConnectionTracer,
+	tracingID uint64,
 	logger utils.Logger,
 	v protocol.VersionNumber,
 ) quicSession {
@@ -416,6 +423,7 @@ var newClientSession = func(
 		s.version,
 	)
 	s.preSetup()
+	s.ctx, s.ctxCancel = context.WithCancel(context.WithValue(context.Background(), SessionTracingKey, tracingID))
 	s.sentPacketHandler, s.receivedPacketHandler = ackhandler.NewAckHandler(
 		initialPacketNumber,
 		getMaxPacketSize(s.conn.RemoteAddr()),
@@ -524,7 +532,6 @@ func (s *session) preSetup() {
 	s.receivedPackets = make(chan *receivedPacket, protocol.MaxSessionUnprocessedPackets)
 	s.closeChan = make(chan closeError, 1)
 	s.sendingScheduled = make(chan struct{}, 1)
-	s.ctx, s.ctxCancel = context.WithCancel(context.Background())
 	s.handshakeCtx, s.handshakeCtxCancel = context.WithCancel(context.Background())
 
 	now := time.Now()

session_test.go

@@ -107,6 +107,7 @@ var _ = Describe("Session", func() {
 			tokenGenerator,
 			false,
 			tracer,
+			1234,
 			utils.DefaultLogger,
 			protocol.VersionTLS,
 		).(*session)
@@ -2478,6 +2479,7 @@ var _ = Describe("Client Session", func() {
 			false,
 			false,
 			tracer,
+			1234,
 			utils.DefaultLogger,
 			protocol.VersionTLS,
 		).(*session)