[receiver/discovery] Remove redundant resource attributes (#5409)

We don't need to send discovery.receiver.type and discovery.receiver.name along with the metrics. They are meant to be used for discovery evaluation only

internal/receiver/discoveryreceiver/metric_evaluator.go

@@ -64,7 +64,7 @@ func (m *metricsConsumer) Capabilities() consumer.Capabilities {
 func (m *metricsConsumer) ConsumeMetrics(ctx context.Context, md pmetric.Metrics) error {
 	m.evaluateMetrics(md)
 	if m.nextConsumer != nil {
-		return m.nextConsumer.ConsumeMetrics(ctx, md)
+		return m.nextConsumer.ConsumeMetrics(ctx, cleanupMetrics(md))
 	}
 	return nil
 }
@@ -154,3 +154,13 @@ func (m *metricsConsumer) findMatchedMetric(md pmetric.Metrics, match Match, rec
 	}
 	return pcommon.NewResource(), false
 }
+
+// cleanupMetrics removes resource attributes used for status correlation.
+func cleanupMetrics(md pmetric.Metrics) pmetric.Metrics {
+	for i := 0; i < md.ResourceMetrics().Len(); i++ {
+		attrs := md.ResourceMetrics().At(i).Resource().Attributes()
+		attrs.Remove(discovery.ReceiverTypeAttr)
+		attrs.Remove(discovery.ReceiverNameAttr)
+	}
+	return md
+}

internal/receiver/discoveryreceiver/metric_evaluator_test.go

@@ -21,9 +21,11 @@ import (
 	"time"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/extension/observer"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/consumer"
+	"go.opentelemetry.io/collector/consumer/consumertest"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.uber.org/zap"
@@ -43,7 +45,7 @@ func TestMetricEvaluatorBaseMetricConsumer(t *testing.T) {
 	require.NoError(t, me.ConsumeMetrics(context.Background(), md))
 }
 
-func TestMetricEvaluation(t *testing.T) {
+func TestConsumeMetrics(t *testing.T) {
 	// If debugging tests, replace the Nop Logger with a test instance to see
 	// all statements. Not in regular use to avoid spamming output.
 	// logger := zaptest.NewLogger(t)
@@ -88,7 +90,8 @@ func TestMetricEvaluation(t *testing.T) {
 					endpointID := observer.EndpointID("endpoint.id")
 					cStore.UpdateEndpoint(observer.Endpoint{ID: endpointID}, receiverID, observerID)
 
-					me := newMetricsConsumer(logger, cfg, cStore, nil)
+					ms := &consumertest.MetricsSink{}
+					me := newMetricsConsumer(logger, cfg, cStore, ms)
 
 					expectedRes := pcommon.NewResource()
 					expectedRes.Attributes().PutStr("discovery.receiver.type", "a_receiver")
@@ -116,7 +119,7 @@ func TestMetricEvaluation(t *testing.T) {
 					sms.AppendEmpty().SetName("desired.name")
 					sms.AppendEmpty().SetName("desired.name")
 
-					me.evaluateMetrics(md)
+					require.NoError(t, me.ConsumeMetrics(context.Background(), md))
 
 					// wait for the emit channel to be processed
 					emitWG.Wait()
@@ -129,6 +132,17 @@ func TestMetricEvaluation(t *testing.T) {
 						"discovery.message":       "desired body content",
 						"extra_attr":              "target_resource",
 					}, cStore.Attrs(endpointID))
+
+					assert.Equal(t, 1, len(ms.AllMetrics()))
+					assert.Equal(t, 2, ms.AllMetrics()[0].ResourceMetrics().Len())
+					// Ensure redundant attributes are not added
+					for i := 0; i < ms.AllMetrics()[0].ResourceMetrics().Len(); i++ {
+						attrs := ms.AllMetrics()[0].ResourceMetrics().At(i).Resource().Attributes()
+						_, ok := attrs.Get(discovery.ReceiverTypeAttr)
+						assert.False(t, ok)
+						_, ok = attrs.Get(discovery.ReceiverNameAttr)
+						assert.False(t, ok)
+					}
 				})
 			}
 		})