stdoutmetric: self-observability: exporter metrics

CHANGELOG.md

@@ -19,6 +19,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Add experimental observability metrics in `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc`. (#7353)
 - Add experimental observability metrics in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc`. (#7459)
 - Add experimental observability metrics in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp`. (#7486)
+- Add experimental observability metrics in `go.opentelemetry.io/otel/exporters/stdout/stdoutmetric`. (#7492)
 
 ### Fixed
 

exporters/stdout/stdoutmetric/exporter.go

@@ -10,6 +10,8 @@ import (
 	"sync"
 	"sync/atomic"
 
+	"go.opentelemetry.io/otel/exporters/stdout/stdoutmetric/internal/counter"
+	"go.opentelemetry.io/otel/exporters/stdout/stdoutmetric/internal/observ"
 	"go.opentelemetry.io/otel/internal/global"
 	"go.opentelemetry.io/otel/sdk/metric"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
@@ -25,6 +27,8 @@ type exporter struct {
 	aggregationSelector metric.AggregationSelector
 
 	redactTimestamps bool
+
+	inst *observ.Instrumentation
 }
 
 // New returns a configured metric exporter.
@@ -39,7 +43,9 @@ func New(options ...Option) (metric.Exporter, error) {
 		redactTimestamps:    cfg.redactTimestamps,
 	}
 	exp.encVal.Store(*cfg.encoder)
-	return exp, nil
+	var err error
+	exp.inst, err = observ.NewInstrumentation(counter.NextExporterID())
+	return exp, err
 }
 
 func (e *exporter) Temporality(k metric.InstrumentKind) metricdata.Temporality {
@@ -50,8 +56,11 @@ func (e *exporter) Aggregation(k metric.InstrumentKind) metric.Aggregation {
 	return e.aggregationSelector(k)
 }
 
-func (e *exporter) Export(ctx context.Context, data *metricdata.ResourceMetrics) error {
-	if err := ctx.Err(); err != nil {
+func (e *exporter) Export(ctx context.Context, data *metricdata.ResourceMetrics) (err error) {
+	trackExportFunc := e.trackExport(ctx, countDataPoints(data))
+	defer func() { trackExportFunc(err) }()
+	err = ctx.Err()
+	if err != nil {
 		return err
 	}
 	if e.redactTimestamps {
@@ -63,6 +72,13 @@ func (e *exporter) Export(ctx context.Context, data *metricdata.ResourceMetrics)
 	return e.encVal.Load().(encoderHolder).Encode(data)
 }
 
+func (e *exporter) trackExport(ctx context.Context, count int64) func(err error) {
+	if e.inst == nil {
+		return func(error) {}
+	}
+	return e.inst.TrackExport(ctx, count)
+}
+
 func (*exporter) ForceFlush(context.Context) error {
 	// exporter holds no state, nothing to flush.
 	return nil
@@ -159,3 +175,37 @@ func redactDataPointTimestamps[T int64 | float64](sdp []metricdata.DataPoint[T])
 	}
 	return out
 }
+
+// countDataPoints counts the total number of data points in a ResourceMetrics.
+func countDataPoints(rm *metricdata.ResourceMetrics) int64 {
+	if rm == nil {
+		return 0
+	}
+
+	var total int64
+	for _, sm := range rm.ScopeMetrics {
+		for _, m := range sm.Metrics {
+			switch data := m.Data.(type) {
+			case metricdata.Gauge[int64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.Gauge[float64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.Sum[int64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.Sum[float64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.Histogram[int64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.Histogram[float64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.ExponentialHistogram[int64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.ExponentialHistogram[float64]:
+				total += int64(len(data.DataPoints))
+			case metricdata.Summary:
+				total += int64(len(data.DataPoints))
+			}
+		}
+	}
+	return total
+}