feat: informative user-agent for otlp exporters

exporter/exporterhelper/common.go

@@ -16,6 +16,8 @@ package exporterhelper // import "go.opentelemetry.io/collector/exporter/exporte
 
 import (
 	"context"
+	"fmt"
+	"runtime"
 	"time"
 
 	"go.opentelemetry.io/collector/component"
@@ -232,3 +234,8 @@ func (ts *timeoutSender) send(req request) error {
 	}
 	return req.export(ctx)
 }
+
+// DefaultUserAgent User-Agent value used by exporters
+func DefaultUserAgent(info component.BuildInfo) string {
+	return fmt.Sprintf("%s/%s (%s/%s)", info.Description, info.Version, runtime.GOOS, runtime.GOARCH)
+}

exporter/otlpexporter/factory.go

@@ -58,7 +58,7 @@ func createTracesExporter(
 	set component.ExporterCreateSettings,
 	cfg config.Exporter,
 ) (component.TracesExporter, error) {
-	oce, err := newExporter(cfg)
+	oce, err := newExporter(cfg, set.BuildInfo)
 	if err != nil {
 		return nil, err
 	}
@@ -80,7 +80,7 @@ func createMetricsExporter(
 	set component.ExporterCreateSettings,
 	cfg config.Exporter,
 ) (component.MetricsExporter, error) {
-	oce, err := newExporter(cfg)
+	oce, err := newExporter(cfg, set.BuildInfo)
 	if err != nil {
 		return nil, err
 	}
@@ -103,7 +103,7 @@ func createLogsExporter(
 	set component.ExporterCreateSettings,
 	cfg config.Exporter,
 ) (component.LogsExporter, error) {
-	oce, err := newExporter(cfg)
+	oce, err := newExporter(cfg, set.BuildInfo)
 	if err != nil {
 		return nil, err
 	}

exporter/otlpexporter/otlp.go

@@ -44,18 +44,21 @@ type exporter struct {
 	clientConn     *grpc.ClientConn
 	metadata       metadata.MD
 	callOptions    []grpc.CallOption
+
+	// Build info for user-agent header.
+	buildInfo component.BuildInfo
 }
 
 // Crete new exporter and start it. The exporter will begin connecting but
 // this function may return before the connection is established.
-func newExporter(cfg config.Exporter) (*exporter, error) {
+func newExporter(cfg config.Exporter, buildInfo component.BuildInfo) (*exporter, error) {
 	oCfg := cfg.(*Config)
 
 	if oCfg.Endpoint == "" {
 		return nil, errors.New("OTLP exporter config requires an Endpoint")
 	}
 
-	return &exporter{config: oCfg}, nil
+	return &exporter{config: oCfg, buildInfo: buildInfo}, nil
 }
 
 // start actually creates the gRPC connection. The client construction is deferred till this point as this
@@ -65,6 +68,7 @@ func (e *exporter) start(_ context.Context, host component.Host) (err error) {
 	if err != nil {
 		return err
 	}
+	dialOpts = append(dialOpts, grpc.WithUserAgent(exporterhelper.DefaultUserAgent(e.buildInfo)))
 
 	if e.clientConn, err = grpc.Dial(e.config.GRPCClientSettings.SanitizedEndpoint(), dialOpts...); err != nil {
 		return err

exporter/otlpexporter/otlp_test.go

@@ -203,6 +203,8 @@ func TestSendTraces(t *testing.T) {
 		},
 	}
 	set := componenttest.NewNopExporterCreateSettings()
+	set.BuildInfo.Description = "Collector"
+	set.BuildInfo.Version = "1.2.3test"
 	exp, err := factory.CreateTracesExporter(context.Background(), set, cfg)
 	require.NoError(t, err)
 	require.NotNil(t, exp)
@@ -247,7 +249,10 @@ func TestSendTraces(t *testing.T) {
 	assert.EqualValues(t, 2, atomic.LoadInt32(&rcv.requestCount))
 	assert.EqualValues(t, td, rcv.GetLastRequest())
 
-	require.EqualValues(t, rcv.GetMetadata().Get("header"), expectedHeader)
+	md := rcv.GetMetadata()
+	require.EqualValues(t, md.Get("header"), expectedHeader)
+	require.Equal(t, len(md.Get("User-Agent")), 1)
+	require.Contains(t, md.Get("User-Agent")[0], "Collector/1.2.3test")
 }
 
 func TestSendTracesWhenEndpointHasHttpScheme(t *testing.T) {
@@ -344,6 +349,8 @@ func TestSendMetrics(t *testing.T) {
 		},
 	}
 	set := componenttest.NewNopExporterCreateSettings()
+	set.BuildInfo.Description = "Collector"
+	set.BuildInfo.Version = "1.2.3test"
 	exp, err := factory.CreateMetricsExporter(context.Background(), set, cfg)
 	require.NoError(t, err)
 	require.NotNil(t, exp)
@@ -388,7 +395,10 @@ func TestSendMetrics(t *testing.T) {
 	assert.EqualValues(t, 4, atomic.LoadInt32(&rcv.totalItems))
 	assert.EqualValues(t, md, rcv.GetLastRequest())
 
-	require.EqualValues(t, rcv.GetMetadata().Get("header"), expectedHeader)
+	mdata := rcv.GetMetadata()
+	require.EqualValues(t, mdata.Get("header"), expectedHeader)
+	require.Equal(t, len(mdata.Get("User-Agent")), 1)
+	require.Contains(t, mdata.Get("User-Agent")[0], "Collector/1.2.3test")
 }
 
 func TestSendTraceDataServerDownAndUp(t *testing.T) {
@@ -545,6 +555,8 @@ func TestSendLogData(t *testing.T) {
 		},
 	}
 	set := componenttest.NewNopExporterCreateSettings()
+	set.BuildInfo.Description = "Collector"
+	set.BuildInfo.Version = "1.2.3test"
 	exp, err := factory.CreateLogsExporter(context.Background(), set, cfg)
 	require.NoError(t, err)
 	require.NotNil(t, exp)
@@ -586,4 +598,8 @@ func TestSendLogData(t *testing.T) {
 	assert.EqualValues(t, 2, atomic.LoadInt32(&rcv.requestCount))
 	assert.EqualValues(t, 2, atomic.LoadInt32(&rcv.totalItems))
 	assert.EqualValues(t, ld, rcv.GetLastRequest())
+
+	md := rcv.GetMetadata()
+	require.Equal(t, len(md.Get("User-Agent")), 1)
+	require.Contains(t, md.Get("User-Agent")[0], "Collector/1.2.3test")
 }

exporter/otlphttpexporter/factory.go

@@ -77,7 +77,7 @@ func createTracesExporter(
 	set component.ExporterCreateSettings,
 	cfg config.Exporter,
 ) (component.TracesExporter, error) {
-	oce, err := newExporter(cfg, set.Logger)
+	oce, err := newExporter(cfg, set.Logger, set.BuildInfo)
 	if err != nil {
 		return nil, err
 	}
@@ -105,7 +105,7 @@ func createMetricsExporter(
 	set component.ExporterCreateSettings,
 	cfg config.Exporter,
 ) (component.MetricsExporter, error) {
-	oce, err := newExporter(cfg, set.Logger)
+	oce, err := newExporter(cfg, set.Logger, set.BuildInfo)
 	if err != nil {
 		return nil, err
 	}
@@ -133,7 +133,7 @@ func createLogsExporter(
 	set component.ExporterCreateSettings,
 	cfg config.Exporter,
 ) (component.LogsExporter, error) {
-	oce, err := newExporter(cfg, set.Logger)
+	oce, err := newExporter(cfg, set.Logger, set.BuildInfo)
 	if err != nil {
 		return nil, err
 	}

exporter/otlphttpexporter/otlp.go

@@ -57,9 +57,14 @@ const (
 )
 
 // Crete new exporter.
-func newExporter(cfg config.Exporter, logger *zap.Logger) (*exporter, error) {
+func newExporter(cfg config.Exporter, logger *zap.Logger, buildInfo component.BuildInfo) (*exporter, error) {
 	oCfg := cfg.(*Config)
 
+	// Configure default user-agent header
+	oCfg.HTTPClientSettings.CustomRoundTripper = func(next http.RoundTripper) (http.RoundTripper, error) {
+		return newUserAgentRoundTripper(next, exporterhelper.DefaultUserAgent(buildInfo)), nil
+	}
+
 	if oCfg.Endpoint != "" {
 		_, err := url.Parse(oCfg.Endpoint)
 		if err != nil {
@@ -213,3 +218,32 @@ func readResponse(resp *http.Response) *status.Status {
 
 	return respStatus
 }
+
+type userAgentRoundTripper struct {
+	next      http.RoundTripper
+	userAgent string
+}
+
+func newUserAgentRoundTripper(next http.RoundTripper, userAgent string) *userAgentRoundTripper {
+	return &userAgentRoundTripper{
+		next,
+		userAgent,
+	}
+}
+
+func (r *userAgentRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	body, readErr := ioutil.ReadAll(req.Body)
+	closeErr := req.Body.Close()
+	if readErr != nil {
+		return nil, readErr
+	}
+	if closeErr != nil {
+		return nil, closeErr
+	}
+	requestClone := req.Clone(req.Context())
+	requestClone.Body = ioutil.NopCloser(bytes.NewReader(body))
+	if requestClone.Header.Get("User-Agent") == "" {
+		requestClone.Header.Set("User-Agent", r.userAgent)
+	}
+	return r.next.RoundTrip(requestClone)
+}

exporter/otlphttpexporter/otlp_test.go

@@ -529,3 +529,167 @@ func TestErrorResponses(t *testing.T) {
 		})
 	}
 }
+
+func TestUserAgent(t *testing.T) {
+	addr := testutil.GetAvailableLocalAddress(t)
+	set := componenttest.NewNopExporterCreateSettings()
+	set.BuildInfo.Description = "Collector"
+	set.BuildInfo.Version = "1.2.3test"
+
+	tests := []struct {
+		name       string
+		headers    map[string]string
+		expectedUA string
+	}{
+		{
+			name:       "default_user_agent",
+			expectedUA: "Collector/1.2.3test",
+		},
+		{
+			name:       "custom_user_agent",
+			headers:    map[string]string{"User-Agent": "My Custom Agent"},
+			expectedUA: "My Custom Agent",
+		},
+		{
+			name:       "custom_user_agent_lowercase",
+			headers:    map[string]string{"user-agent": "My Custom Agent"},
+			expectedUA: "My Custom Agent",
+		},
+	}
+
+	t.Run("traces", func(t *testing.T) {
+		for _, test := range tests {
+			t.Run(test.name, func(t *testing.T) {
+				mux := http.NewServeMux()
+				mux.HandleFunc("/v1/traces", func(writer http.ResponseWriter, request *http.Request) {
+					assert.Contains(t, request.Header.Get("user-agent"), test.expectedUA)
+					writer.WriteHeader(200)
+				})
+				srv := http.Server{
+					Addr:    addr,
+					Handler: mux,
+				}
+				ln, err := net.Listen("tcp", addr)
+				require.NoError(t, err)
+				go func() {
+					_ = srv.Serve(ln)
+				}()
+
+				cfg := &Config{
+					ExporterSettings: config.NewExporterSettings(config.NewComponentID(typeStr)),
+					TracesEndpoint:   fmt.Sprintf("http://%s/v1/traces", addr),
+					HTTPClientSettings: confighttp.HTTPClientSettings{
+						Headers: test.headers,
+					},
+				}
+				exp, err := createTracesExporter(context.Background(), set, cfg)
+				require.NoError(t, err)
+
+				// start the exporter
+				err = exp.Start(context.Background(), componenttest.NewNopHost())
+				require.NoError(t, err)
+				t.Cleanup(func() {
+					require.NoError(t, exp.Shutdown(context.Background()))
+				})
+
+				// generate data
+				traces := pdata.NewTraces()
+				err = exp.ConsumeTraces(context.Background(), traces)
+				require.NoError(t, err)
+
+				srv.Close()
+			})
+		}
+	})
+
+	t.Run("metrics", func(t *testing.T) {
+		for _, test := range tests {
+			t.Run(test.name, func(t *testing.T) {
+				mux := http.NewServeMux()
+				mux.HandleFunc("/v1/metrics", func(writer http.ResponseWriter, request *http.Request) {
+					assert.Contains(t, request.Header.Get("user-agent"), test.expectedUA)
+					writer.WriteHeader(200)
+				})
+				srv := http.Server{
+					Addr:    addr,
+					Handler: mux,
+				}
+				ln, err := net.Listen("tcp", addr)
+				require.NoError(t, err)
+				go func() {
+					_ = srv.Serve(ln)
+				}()
+
+				cfg := &Config{
+					ExporterSettings: config.NewExporterSettings(config.NewComponentID(typeStr)),
+					MetricsEndpoint:  fmt.Sprintf("http://%s/v1/metrics", addr),
+					HTTPClientSettings: confighttp.HTTPClientSettings{
+						Headers: test.headers,
+					},
+				}
+				exp, err := createMetricsExporter(context.Background(), set, cfg)
+				require.NoError(t, err)
+
+				// start the exporter
+				err = exp.Start(context.Background(), componenttest.NewNopHost())
+				require.NoError(t, err)
+				t.Cleanup(func() {
+					require.NoError(t, exp.Shutdown(context.Background()))
+				})
+
+				// generate data
+				metrics := pdata.NewMetrics()
+				err = exp.ConsumeMetrics(context.Background(), metrics)
+				require.NoError(t, err)
+
+				srv.Close()
+			})
+		}
+	})
+
+	t.Run("logs", func(t *testing.T) {
+		for _, test := range tests {
+			t.Run(test.name, func(t *testing.T) {
+				mux := http.NewServeMux()
+				mux.HandleFunc("/v1/logs", func(writer http.ResponseWriter, request *http.Request) {
+					assert.Contains(t, request.Header.Get("user-agent"), test.expectedUA)
+					writer.WriteHeader(200)
+				})
+				srv := http.Server{
+					Addr:    addr,
+					Handler: mux,
+				}
+				ln, err := net.Listen("tcp", addr)
+				require.NoError(t, err)
+				go func() {
+					_ = srv.Serve(ln)
+				}()
+
+				cfg := &Config{
+					ExporterSettings: config.NewExporterSettings(config.NewComponentID(typeStr)),
+					LogsEndpoint:     fmt.Sprintf("http://%s/v1/logs", addr),
+					HTTPClientSettings: confighttp.HTTPClientSettings{
+						Headers: test.headers,
+					},
+				}
+				exp, err := createLogsExporter(context.Background(), set, cfg)
+				require.NoError(t, err)
+
+				// start the exporter
+				err = exp.Start(context.Background(), componenttest.NewNopHost())
+				require.NoError(t, err)
+				t.Cleanup(func() {
+					require.NoError(t, exp.Shutdown(context.Background()))
+				})
+
+				// generate data
+				logs := pdata.NewLogs()
+				err = exp.ConsumeLogs(context.Background(), logs)
+				require.NoError(t, err)
+
+				srv.Close()
+
+			})
+		}
+	})
+}