feat: add self-observability metrics to otlpmetricgrpc metric exporters

exporters/otlp/otlpmetric/otlpmetricgrpc/doc.go

@@ -77,6 +77,21 @@ default aggregation to use for histogram instruments. Supported values:
 
 The configuration can be overridden by [WithAggregationSelector] option.
 
+# Self-Observability
+
+This exporter supports self-observability metrics to monitor its own performance.
+To enable this experimental feature, set the environment variable:
+
+	OTEL_GO_X_SELF_OBSERVABILITY=true
+
+When enabled, the exporter will emit the following metrics using the global MeterProvider:
+
+  - otel.sdk.exporter.metric_data_point.exported: Counter tracking successfully exported data points
+  - otel.sdk.exporter.metric_data_point.inflight: UpDownCounter tracking data points currently being exported
+  - otel.sdk.exporter.operation.duration: Histogram tracking export operation duration in seconds
+
+All metrics include attributes identifying the exporter component and destination server.
+
 [W3C Baggage HTTP Header Content Format]: https://www.w3.org/TR/baggage/#header-content
 [Explicit Bucket Histogram Aggregation]: https://github.com/open-telemetry/opentelemetry-specification/blob/v1.26.0/specification/metrics/sdk.md#explicit-bucket-histogram-aggregation
 [Base2 Exponential Bucket Histogram Aggregation]: https://github.com/open-telemetry/opentelemetry-specification/blob/v1.26.0/specification/metrics/sdk.md#base2-exponential-bucket-histogram-aggregation

exporters/otlp/otlpmetric/otlpmetricgrpc/exporter.go

@@ -10,6 +10,7 @@ import (
 	"sync"
 
 	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc/internal/oconf"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc/internal/selfobservability"
 	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc/internal/transform"
 	"go.opentelemetry.io/otel/internal/global"
 	"go.opentelemetry.io/otel/sdk/metric"
@@ -30,6 +31,9 @@ type Exporter struct {
 	aggregationSelector metric.AggregationSelector
 
 	shutdownOnce sync.Once
+
+	// Self-observability metrics
+	metrics *selfobservability.ExporterMetrics
 }
 
 func newExporter(c *client, cfg oconf.Config) (*Exporter, error) {
@@ -45,11 +49,20 @@ func newExporter(c *client, cfg oconf.Config) (*Exporter, error) {
 		as = metric.DefaultAggregationSelector
 	}
 
+	// Extract server address and port from endpoint for self-observability
+	serverAddress, serverPort := selfobservability.ParseEndpoint(cfg.Metrics.Endpoint, 4317)
+
 	return &Exporter{
 		client: c,
 
 		temporalitySelector: ts,
 		aggregationSelector: as,
+
+		metrics: selfobservability.NewExporterMetrics(
+			"otlp_grpc_metric_exporter",
+			serverAddress,
+			serverPort,
+		),
 	}, nil
 }
 
@@ -70,19 +83,29 @@ func (e *Exporter) Aggregation(k metric.InstrumentKind) metric.Aggregation {
 func (e *Exporter) Export(ctx context.Context, rm *metricdata.ResourceMetrics) error {
 	defer global.Debug("OTLP/gRPC exporter export", "Data", rm)
 
+	// Track export operation for self-observability
+	finishTracking := e.metrics.TrackExport(ctx, rm)
+
 	otlpRm, err := transform.ResourceMetrics(rm)
 	// Best effort upload of transformable metrics.
 	e.clientMu.Lock()
 	upErr := e.client.UploadMetrics(ctx, otlpRm)
 	e.clientMu.Unlock()
+
+	// Complete tracking with the final result
+	var finalErr error
 	if upErr != nil {
 		if err == nil {
-			return fmt.Errorf("failed to upload metrics: %w", upErr)
+			finalErr = fmt.Errorf("failed to upload metrics: %w", upErr)
+		} else {
+			finalErr = fmt.Errorf("failed to upload incomplete metrics (%w): %w", err, upErr)
 		}
-		// Merge the two errors.
-		return fmt.Errorf("failed to upload incomplete metrics (%w): %w", err, upErr)
+	} else {
+		finalErr = err
 	}
-	return err
+
+	finishTracking(finalErr)
+	return finalErr
 }
 
 // ForceFlush flushes any metric data held by an exporter.

exporters/otlp/otlpmetric/otlpmetricgrpc/exporter_test.go

@@ -62,8 +62,8 @@ func TestExporterClientConcurrentSafe(t *testing.T) {
 	}
 
 	someWork.Wait()
-	assert.NoError(t, exp.Shutdown(ctx))
-	assert.ErrorIs(t, exp.Shutdown(ctx), errShutdown)
+	require.NoError(t, exp.Shutdown(ctx))
+	require.ErrorIs(t, exp.Shutdown(ctx), errShutdown)
 
 	close(done)
 	wg.Wait()
@@ -90,7 +90,9 @@ func TestExporterDoesNotBlockTemporalityAndAggregation(t *testing.T) {
 		defer wg.Done()
 		rm := new(metricdata.ResourceMetrics)
 		t.Log("starting export")
-		require.NoError(t, exp.Export(ctx, rm))
+		if err := exp.Export(ctx, rm); err != nil {
+			t.Errorf("export failed: %v", err)
+		}
 		t.Log("export complete")
 	}()
 

exporters/otlp/otlpmetric/otlpmetricgrpc/go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/google/go-cmp v0.7.0
 	github.com/stretchr/testify v1.10.0
 	go.opentelemetry.io/otel v1.37.0
+	go.opentelemetry.io/otel/metric v1.37.0
 	go.opentelemetry.io/otel/sdk v1.37.0
 	go.opentelemetry.io/otel/sdk/metric v1.37.0
 	go.opentelemetry.io/proto/otlp v1.7.1
@@ -25,7 +26,6 @@ require (
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
-	go.opentelemetry.io/otel/metric v1.37.0 // indirect
 	go.opentelemetry.io/otel/trace v1.37.0 // indirect
 	golang.org/x/net v0.42.0 // indirect
 	golang.org/x/sys v0.34.0 // indirect

exporters/otlp/otlpmetric/otlpmetricgrpc/internal/gen.go

@@ -30,3 +30,6 @@ package internal // import "go.opentelemetry.io/otel/exporters/otlp/otlpmetric/o
 //go:generate gotmpl --body=../../../../../internal/shared/otlp/otlpmetric/transform/error_test.go.tmpl "--data={}" --out=transform/error_test.go
 //go:generate gotmpl --body=../../../../../internal/shared/otlp/otlpmetric/transform/metricdata.go.tmpl "--data={}" --out=transform/metricdata.go
 //go:generate gotmpl --body=../../../../../internal/shared/otlp/otlpmetric/transform/metricdata_test.go.tmpl "--data={}" --out=transform/metricdata_test.go
+
+//go:generate gotmpl --body=../../../../../internal/shared/otlp/otlpmetric/selfobservability/selfobservability.go.tmpl "--data={}" --out=selfobservability/selfobservability.go
+//go:generate gotmpl --body=../../../../../internal/shared/otlp/otlpmetric/selfobservability/selfobservability_test.go.tmpl "--data={}" --out=selfobservability/selfobservability_test.go