TUN-3471: Add structured log context to logs

connection/connection.go

@@ -11,9 +11,7 @@ import (
 	"github.com/google/uuid"
 )
 
-const (
-	lbProbeUserAgentPrefix = "Mozilla/5.0 (compatible; Cloudflare-Traffic-Manager/1.0; +https://www.cloudflare.com/traffic-manager/;"
-)
+const LogFieldConnIndex = "connIndex"
 
 type Config struct {
 	OriginClient    OriginClient

connection/errors.go

@@ -63,13 +63,18 @@ func (e muxerShutdownError) Error() string {
 }
 
 func isHandshakeErrRecoverable(err error, connIndex uint8, observer *Observer) bool {
+	log := observer.log.With().
+		Uint8(LogFieldConnIndex, connIndex).
+		Err(err).
+		Logger()
+
 	switch err.(type) {
 	case edgediscovery.DialError:
-		observer.log.Error().Msgf("Connection %d unable to dial edge: %s", connIndex, err)
+		log.Error().Msg("Connection unable to dial edge")
 	case h2mux.MuxerHandshakeError:
-		observer.log.Error().Msgf("Connection %d handshake with edge server failed: %s", connIndex, err)
+		log.Error().Msg("Connection handshake with edge server failed")
 	default:
-		observer.log.Error().Msgf("Connection %d failed: %s", connIndex, err)
+		log.Error().Msg("Connection failed")
 		return false
 	}
 	return true

connection/h2mux.go

@@ -51,7 +51,7 @@ func (mc *MuxerConfig) H2MuxerConfig(h h2mux.MuxedStreamHandler, log *zerolog.Lo
 }
 
 // NewTunnelHandler returns a TunnelHandler, origin LAN IP and error
-func NewH2muxConnection(ctx context.Context,
+func NewH2muxConnection(
 	config *Config,
 	muxerConfig *MuxerConfig,
 	edgeConn net.Conn,
@@ -123,7 +123,9 @@ func (h *h2muxConnection) ServeClassicTunnel(ctx context.Context, classicTunnel
 				return nil
 			}
 			// log errors and proceed to RegisterTunnel
-			h.observer.log.Error().Msgf("Couldn't reconnect connection %d. Reregistering it instead. Error was: %v", h.connIndex, err)
+			h.observer.log.Err(err).
+				Uint8(LogFieldConnIndex, h.connIndex).
+				Msg("Couldn't reconnect connection. Re-registering it instead.")
 		}
 		return h.registerTunnel(ctx, credentialManager, classicTunnel, registrationOptions)
 	})

connection/h2mux_test.go

@@ -26,7 +26,7 @@ var (
 	}
 )
 
-func newH2MuxConnection(ctx context.Context, t require.TestingT) (*h2muxConnection, *h2mux.Muxer) {
+func newH2MuxConnection(t require.TestingT) (*h2muxConnection, *h2mux.Muxer) {
 	edgeConn, originConn := net.Pipe()
 	edgeMuxChan := make(chan *h2mux.Muxer)
 	go func() {
@@ -38,7 +38,7 @@ func newH2MuxConnection(ctx context.Context, t require.TestingT) (*h2muxConnecti
 		edgeMuxChan <- edgeMux
 	}()
 	var connIndex = uint8(0)
-	h2muxConn, err, _ := NewH2muxConnection(ctx, testConfig, testMuxerConfig, originConn, connIndex, testObserver)
+	h2muxConn, err, _ := NewH2muxConnection(testConfig, testMuxerConfig, originConn, connIndex, testObserver)
 	require.NoError(t, err)
 	return h2muxConn, <-edgeMuxChan
 }
@@ -79,7 +79,7 @@ func TestServeStreamHTTP(t *testing.T) {
 	}
 
 	ctx, cancel := context.WithCancel(context.Background())
-	h2muxConn, edgeMux := newH2MuxConnection(ctx, t)
+	h2muxConn, edgeMux := newH2MuxConnection(t)
 
 	var wg sync.WaitGroup
 	wg.Add(2)
@@ -120,7 +120,7 @@ func TestServeStreamHTTP(t *testing.T) {
 
 func TestServeStreamWS(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
-	h2muxConn, edgeMux := newH2MuxConnection(ctx, t)
+	h2muxConn, edgeMux := newH2MuxConnection(t)
 
 	var wg sync.WaitGroup
 	wg.Add(2)
@@ -179,7 +179,7 @@ func hasHeader(stream *h2mux.MuxedStream, name, val string) bool {
 
 func benchmarkServeStreamHTTPSimple(b *testing.B, test testRequest) {
 	ctx, cancel := context.WithCancel(context.Background())
-	h2muxConn, edgeMux := newH2MuxConnection(ctx, b)
+	h2muxConn, edgeMux := newH2MuxConnection(b)
 
 	var wg sync.WaitGroup
 	wg.Add(2)

connection/http2.go

@@ -2,7 +2,6 @@ package connection
 
 import (
 	"context"
-	"errors"
 	"io"
 	"math"
 	"net"
@@ -23,10 +22,6 @@ const (
 	controlStreamUpgrade  = "control-stream"
 )
 
-var (
-	errNotFlusher = errors.New("ResponseWriter doesn't implement http.Flusher")
-)
-
 type http2Connection struct {
 	conn         net.Conn
 	server       *http2.Server

connection/metrics.go

@@ -380,7 +380,7 @@ func newTunnelMetrics() *tunnelMetrics {
 		serverLocations:     serverLocations,
 		oldServerLocations:  make(map[string]string),
 		muxerMetrics:        newMuxerMetrics(),
-		tunnelsHA:           NewTunnelsForHA(),
+		tunnelsHA:           newTunnelsForHA(),
 		regSuccess:          registerSuccess,
 		regFail:             registerFail,
 		rpcFail:             rpcFail,

connection/observer.go

@@ -10,6 +10,8 @@ import (
 	"github.com/rs/zerolog"
 )
 
+const LogFieldLocation = "location"
+
 type Observer struct {
 	log              *zerolog.Logger
 	metrics          *tunnelMetrics
@@ -28,7 +30,10 @@ func NewObserver(log *zerolog.Logger, tunnelEventChans []chan Event, uiEnabled b
 
 func (o *Observer) logServerInfo(connIndex uint8, location, msg string) {
 	o.sendEvent(Event{Index: connIndex, EventType: Connected, Location: location})
-	o.log.Info().Msgf(msg)
+	o.log.Info().
+		Uint8(LogFieldConnIndex, connIndex).
+		Str(LogFieldLocation, location).
+		Msg(msg)
 	o.metrics.registerServerLocation(uint8ToString(connIndex), location)
 }
 

connection/protocol.go

@@ -118,7 +118,7 @@ func (s *autoProtocolSelector) Current() Protocol {
 
 	percentage, err := s.fetchFunc()
 	if err != nil {
-		s.log.Error().Msgf("Failed to refresh protocol, err: %v", err)
+		s.log.Err(err).Msg("Failed to refresh protocol")
 		return s.current
 	}
 

connection/rpc.go

@@ -109,7 +109,7 @@ func (rsc *registrationServerClient) RegisterConnection(
 
 	observer.metrics.regSuccess.WithLabelValues("registerConnection").Inc()
 
-	observer.logServerInfo(connIndex, conn.Location, fmt.Sprintf("Connection %d registered with %s using ID %s", connIndex, conn.Location, conn.UUID))
+	observer.logServerInfo(connIndex, conn.Location, fmt.Sprintf("Connection %s registered", conn.UUID))
 	observer.sendConnectedEvent(connIndex, conn.Location)
 
 	return nil
@@ -260,15 +260,15 @@ func (h *h2muxConnection) logServerInfo(ctx context.Context, rpcClient *tunnelSe
 	})
 	serverInfoMessage, err := serverInfoPromise.Result().Struct()
 	if err != nil {
-		h.observer.log.Error().Msgf("Failed to retrieve server information: %s", err)
+		h.observer.log.Err(err).Msg("Failed to retrieve server information")
 		return err
 	}
 	serverInfo, err := tunnelpogs.UnmarshalServerInfo(serverInfoMessage)
 	if err != nil {
-		h.observer.log.Error().Msgf("Failed to retrieve server information: %s", err)
+		h.observer.log.Err(err).Msg("Failed to retrieve server information")
 		return err
 	}
-	h.observer.logServerInfo(h.connIndex, serverInfo.LocationName, fmt.Sprintf("Connection %d connected to %s", h.connIndex, serverInfo.LocationName))
+	h.observer.logServerInfo(h.connIndex, serverInfo.LocationName, "Connection established")
 	return nil
 }
 

connection/tunnelsforha.go

@@ -15,7 +15,7 @@ type tunnelsForHA struct {
 }
 
 // NewTunnelsForHA initializes the Prometheus metrics etc for a tunnelsForHA.
-func NewTunnelsForHA() tunnelsForHA {
+func newTunnelsForHA() tunnelsForHA {
 	metrics := prometheus.NewGaugeVec(
 		prometheus.GaugeOpts{
 			Name: "tunnel_ids",