Set Headers when using gRPC

pkg/export/otel/common.go

@@ -230,6 +230,7 @@ type otlpOptions struct {
 	URLPath       string
 	SkipTLSVerify bool
 	HTTPHeaders   map[string]string
+	GRPCHeaders   map[string]string
 }
 
 func (o *otlpOptions) AsMetricHTTP() []otlpmetrichttp.Option {
@@ -261,6 +262,9 @@ func (o *otlpOptions) AsMetricGRPC() []otlpmetricgrpc.Option {
 	if o.SkipTLSVerify {
 		opts = append(opts, otlpmetricgrpc.WithTLSCredentials(credentials.NewTLS(&tls.Config{InsecureSkipVerify: true})))
 	}
+	if len(o.GRPCHeaders) > 0 {
+		opts = append(opts, otlpmetricgrpc.WithHeaders(o.GRPCHeaders))
+	}
 	return opts
 }
 
@@ -293,6 +297,9 @@ func (o *otlpOptions) AsTraceGRPC() []otlptracegrpc.Option {
 	if o.SkipTLSVerify {
 		opts = append(opts, otlptracegrpc.WithTLSCredentials(credentials.NewTLS(&tls.Config{InsecureSkipVerify: true})))
 	}
+	if len(o.GRPCHeaders) > 0 {
+		opts = append(opts, otlptracegrpc.WithHeaders(o.GRPCHeaders))
+	}
 	return opts
 }
 

pkg/export/otel/traces.go

@@ -349,6 +349,7 @@ func getTracesExporter(ctx context.Context, cfg TracesConfig, ctxInfo *global.Co
 				Insecure:           opts.Insecure,
 				InsecureSkipVerify: cfg.InsecureSkipVerify,
 			},
+			Headers: convertHeaders(opts.GRPCHeaders),
 		}
 		set := getTraceSettings(ctxInfo, t)
 		return factory.CreateTraces(ctx, set, config)
@@ -797,7 +798,7 @@ func getHTTPTracesEndpointOptions(cfg *TracesConfig) (otlpOptions, error) {
 }
 
 func getGRPCTracesEndpointOptions(cfg *TracesConfig) (otlpOptions, error) {
-	opts := otlpOptions{}
+	opts := otlpOptions{GRPCHeaders: map[string]string{}}
 	log := tlog().With("transport", "grpc")
 	murl, _, err := parseTracesEndpoint(cfg)
 	if err != nil {
@@ -816,7 +817,8 @@ func getGRPCTracesEndpointOptions(cfg *TracesConfig) (otlpOptions, error) {
 		log.Debug("Setting InsecureSkipVerify")
 		opts.SkipTLSVerify = true
 	}
-
+	maps.Copy(opts.GRPCHeaders, headersFromEnv(envHeaders))
+	maps.Copy(opts.GRPCHeaders, headersFromEnv(envTracesHeaders))
 	return opts, nil
 }
 

pkg/export/otel/traces_test.go

@@ -200,7 +200,7 @@ func TestGRPCTracesEndpointOptions(t *testing.T) {
 	}
 
 	t.Run("testing with two endpoints", func(t *testing.T) {
-		testTracesGRPOptions(t, otlpOptions{Endpoint: "localhost:3232"}, &tcfg)
+		testTracesGRPCOptions(t, otlpOptions{Endpoint: "localhost:3232", GRPCHeaders: map[string]string{}}, &tcfg)
 	})
 
 	tcfg = TracesConfig{
@@ -209,7 +209,7 @@ func TestGRPCTracesEndpointOptions(t *testing.T) {
 	}
 
 	t.Run("testing with only common endpoint", func(t *testing.T) {
-		testTracesGRPOptions(t, otlpOptions{Endpoint: "localhost:3131"}, &tcfg)
+		testTracesGRPCOptions(t, otlpOptions{Endpoint: "localhost:3131", GRPCHeaders: map[string]string{}}, &tcfg)
 	})
 
 	tcfg = TracesConfig{
@@ -218,7 +218,7 @@ func TestGRPCTracesEndpointOptions(t *testing.T) {
 		Instrumentations: []string{instrumentations.InstrumentationALL},
 	}
 	t.Run("testing with insecure endpoint", func(t *testing.T) {
-		testTracesGRPOptions(t, otlpOptions{Endpoint: "localhost:3232", Insecure: true}, &tcfg)
+		testTracesGRPCOptions(t, otlpOptions{Endpoint: "localhost:3232", Insecure: true, GRPCHeaders: map[string]string{}}, &tcfg)
 	})
 
 	tcfg = TracesConfig{
@@ -228,11 +228,58 @@ func TestGRPCTracesEndpointOptions(t *testing.T) {
 	}
 
 	t.Run("testing with skip TLS verification", func(t *testing.T) {
-		testTracesGRPOptions(t, otlpOptions{Endpoint: "localhost:3232", SkipTLSVerify: true}, &tcfg)
+		testTracesGRPCOptions(t, otlpOptions{Endpoint: "localhost:3232", SkipTLSVerify: true, GRPCHeaders: map[string]string{}}, &tcfg)
 	})
 }
 
-func testTracesGRPOptions(t *testing.T, expected otlpOptions, tcfg *TracesConfig) {
+func TestGRPCTracesEndpointHeaders(t *testing.T) {
+	type testCase struct {
+		Description     string
+		Env             map[string]string
+		ExpectedHeaders map[string]string
+		Grafana         GrafanaOTLP
+	}
+	for _, tc := range []testCase{
+		{Description: "No headers",
+			ExpectedHeaders: map[string]string{}},
+		{Description: "defining common OTLP_HEADERS",
+			Env:             map[string]string{"OTEL_EXPORTER_OTLP_HEADERS": "Foo=Bar ==,Authorization=Base 2222=="},
+			ExpectedHeaders: map[string]string{"Foo": "Bar ==", "Authorization": "Base 2222=="}},
+		{Description: "defining common OTLP_TRACES_HEADERS",
+			Env:             map[string]string{"OTEL_EXPORTER_OTLP_TRACES_HEADERS": "Foo=Bar ==,Authorization=Base 1234=="},
+			ExpectedHeaders: map[string]string{"Foo": "Bar ==", "Authorization": "Base 1234=="}},
+		{Description: "OTLP_TRACES_HEADERS takes precedence over OTLP_HEADERS",
+			Env: map[string]string{
+				"OTEL_EXPORTER_OTLP_HEADERS":        "Foo=Bar ==,Authorization=Base 3210==",
+				"OTEL_EXPORTER_OTLP_TRACES_HEADERS": "Authorization=Base 1111==",
+			},
+			ExpectedHeaders: map[string]string{"Foo": "Bar ==", "Authorization": "Base 1111=="}},
+	} {
+		// mutex to avoid running testcases in parallel so we don't mess up with env vars
+		mt := sync.Mutex{}
+		t.Run(fmt.Sprint(tc.Description), func(t *testing.T) {
+			mt.Lock()
+			restore := restoreEnvAfterExecution()
+			defer func() {
+				restore()
+				mt.Unlock()
+			}()
+			for k, v := range tc.Env {
+				require.NoError(t, os.Setenv(k, v))
+			}
+
+			opts, err := getGRPCTracesEndpointOptions(&TracesConfig{
+				TracesEndpoint:   "https://localhost:1234/v1/traces",
+				Grafana:          &tc.Grafana,
+				Instrumentations: []string{instrumentations.InstrumentationALL},
+			})
+			require.NoError(t, err)
+			assert.Equal(t, tc.ExpectedHeaders, opts.GRPCHeaders)
+		})
+	}
+}
+
+func testTracesGRPCOptions(t *testing.T, expected otlpOptions, tcfg *TracesConfig) {
 	defer restoreEnvAfterExecution()()
 	opts, err := getGRPCTracesEndpointOptions(tcfg)
 	require.NoError(t, err)