filter metrics

elastic · Aug 23, 2023 · 1a424e4 · 1a424e4
1 parent b5081b3
commit 1a424e4
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Showing 3 changed files with 61 additions and 3 deletions.
diff --git a/internal/telemetry/metric_exporter.go b/internal/telemetry/metric_exporter.go
@@ -39,6 +39,7 @@ func NewMetricExporter(p modelpb.BatchProcessor, opts ...ConfigOption) *MetricEx
 	return &MetricExporter{
 		processor: p,
 
+		metricFilter:        cfg.MetricFilter,
 		temporalitySelector: cfg.TemporalitySelector,
 		aggregationSelector: cfg.AggregationSelector,
 	}
@@ -49,6 +50,7 @@ func NewMetricExporter(p modelpb.BatchProcessor, opts ...ConfigOption) *MetricEx
 type MetricExporter struct {
 	processor modelpb.BatchProcessor
 
+	metricFilter        []string
 	temporalitySelector metric.TemporalitySelector
 	aggregationSelector metric.AggregationSelector
 }
@@ -84,6 +86,10 @@ func (e *MetricExporter) Export(ctx context.Context, rm *metricdata.ResourceMetr
 	for _, scopeMetrics := range rm.ScopeMetrics {
 		ms := make(metricsets)
 		for _, sm := range scopeMetrics.Metrics {
+			if e.isMetricFiltered(sm.Name) {
+				continue
+			}
+
 			if err := addMetric(sm, ms); err != nil {
 				return err
 			}
@@ -117,10 +123,22 @@ func (e *MetricExporter) Export(ctx context.Context, rm *metricdata.ResourceMetr
 			batch = append(batch, event)
 		}
 	}
+	if len(batch) == 0 {
+		return nil
+	}
 
 	return e.processor.ProcessBatch(ctx, &batch)
 }
 
+func (e *MetricExporter) isMetricFiltered(n string) bool {
+	for _, v := range e.metricFilter {
+		if v == n {
+			return false
+		}
+	}
+	return true
+}
+
 func addMetric(sm metricdata.Metrics, ms metricsets) error {
 	switch m := sm.Data.(type) {
 	case metricdata.Histogram[int64]:

diff --git a/internal/telemetry/metric_exporter_config.go b/internal/telemetry/metric_exporter_config.go
@@ -33,6 +33,7 @@ var customHistogramBoundaries = []float64{
 }
 
 type Config struct {
+	MetricFilter        []string
 	TemporalitySelector metric.TemporalitySelector
 	AggregationSelector metric.AggregationSelector
 }
@@ -74,6 +75,17 @@ func defaultAggregationSelector(ik metric.InstrumentKind) aggregation.Aggregatio
 	}
 }
 
+// WithMetricFilter configured the metrics filter. Any metric filtered here
+// will be the only ones to be exported. All other metrics will be ignored.
+//
+// Defaults to not exporting anything.
+func WithMetricFilter(f []string) ConfigOption {
+	return func(cfg Config) Config {
+		cfg.MetricFilter = f
+		return cfg
+	}
+}
+
 // WithAggregationSelector configure the Aggregation Selector the exporter will
 // use. If no AggregationSelector is provided the DefaultAggregationSelector is
 // used.

diff --git a/internal/telemetry/metric_exporter_test.go b/internal/telemetry/metric_exporter_test.go
@@ -42,11 +42,24 @@ func TestMetricExporter(t *testing.T) {
 	for _, tt := range []struct {
 		name string
 
-		recordMetrics func(ctx context.Context, meter metric.Meter)
-		expectedBatch modelpb.Batch
+		exporterConfig []ConfigOption
+		recordMetrics  func(ctx context.Context, meter metric.Meter)
+		expectedBatch  modelpb.Batch
 	}{
+		{
+			name: "with a filtered metric",
+			recordMetrics: func(ctx context.Context, meter metric.Meter) {
+				counter, err := meter.Int64Counter("filtered_metric")
+				assert.NoError(t, err)
+				counter.Add(ctx, 1)
+			},
+			expectedBatch: modelpb.Batch(nil),
+		},
 		{
 			name: "with an int64 histogram",
+			exporterConfig: []ConfigOption{
+				WithMetricFilter([]string{"histogram_metric"}),
+			},
 			recordMetrics: func(ctx context.Context, meter metric.Meter) {
 				counter, err := meter.Int64Histogram("histogram_metric")
 				assert.NoError(t, err)
@@ -100,6 +113,9 @@ func TestMetricExporter(t *testing.T) {
 		},
 		{
 			name: "with a float64 histogram",
+			exporterConfig: []ConfigOption{
+				WithMetricFilter([]string{"histogram_metric"}),
+			},
 			recordMetrics: func(ctx context.Context, meter metric.Meter) {
 				counter, err := meter.Float64Histogram("histogram_metric")
 				assert.NoError(t, err)
@@ -183,6 +199,9 @@ func TestMetricExporter(t *testing.T) {
 		},
 		{
 			name: "with an int64 counter",
+			exporterConfig: []ConfigOption{
+				WithMetricFilter([]string{"sum_metric"}),
+			},
 			recordMetrics: func(ctx context.Context, meter metric.Meter) {
 				counter, err := meter.Int64Counter("sum_metric")
 				assert.NoError(t, err)
@@ -204,6 +223,9 @@ func TestMetricExporter(t *testing.T) {
 		},
 		{
 			name: "with a float64 counter",
+			exporterConfig: []ConfigOption{
+				WithMetricFilter([]string{"sum_metric"}),
+			},
 			recordMetrics: func(ctx context.Context, meter metric.Meter) {
 				counter, err := meter.Float64Counter("sum_metric")
 				assert.NoError(t, err)
@@ -225,6 +247,9 @@ func TestMetricExporter(t *testing.T) {
 		},
 		{
 			name: "with an int64 gauge",
+			exporterConfig: []ConfigOption{
+				WithMetricFilter([]string{"gauge_metric"}),
+			},
 			recordMetrics: func(ctx context.Context, meter metric.Meter) {
 				counter, err := meter.Int64UpDownCounter("gauge_metric")
 				assert.NoError(t, err)
@@ -246,6 +271,9 @@ func TestMetricExporter(t *testing.T) {
 		},
 		{
 			name: "with a float64 gauge",
+			exporterConfig: []ConfigOption{
+				WithMetricFilter([]string{"gauge_metric"}),
+			},
 			recordMetrics: func(ctx context.Context, meter metric.Meter) {
 				counter, err := meter.Float64UpDownCounter("gauge_metric")
 				assert.NoError(t, err)
@@ -274,7 +302,7 @@ func TestMetricExporter(t *testing.T) {
 				batch = append(batch, (*b)...)
 				return nil
 			})
-			e := NewMetricExporter(p)
+			e := NewMetricExporter(p, tt.exporterConfig...)
 
 			provider := sdkmetric.NewMeterProvider(
 				sdkmetric.WithReader(sdkmetric.NewPeriodicReader(e)),