[receiver/prometheus] Add support for otel_scope_schema_url label

.chloggen/prometheusreceiver_add_otel_scope_schema_url_support.yaml

@@ -0,0 +1,22 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: receiver/prometheus
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add support for otel_scope_schema_url label mapping to OpenTelemetry ScopeMetrics schema URL field
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [41488]
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

pkg/translator/prometheus/constants.go

@@ -28,6 +28,10 @@ const (
 	// version of the OpenTelemetry scope which produced the metric:
 	// https://github.com/open-telemetry/opentelemetry-specification/blob/e6eccba97ebaffbbfad6d4358408a2cead0ec2df/specification/compatibility/prometheus_and_openmetrics.md#instrumentation-scope
 	ScopeVersionLabelKey = "otel_scope_version"
+	// ScopeSchemaURLLabelKey is the name of the label key used to identify the
+	// schema URL of the OpenTelemetry scope which produced the metric:
+	// https://github.com/open-telemetry/opentelemetry-specification/blob/e6eccba97ebaffbbfad6d4358408a2cead0ec2df/specification/compatibility/prometheus_and_openmetrics.md#instrumentation-scope
+	ScopeSchemaURLLabelKey = "otel_scope_schema_url"
 	// TargetInfoMetricName is the name of the metric used to preserve resource
 	// attributes in Prometheus format:
 	// https://github.com/open-telemetry/opentelemetry-specification/blob/e6eccba97ebaffbbfad6d4358408a2cead0ec2df/specification/compatibility/prometheus_and_openmetrics.md#resource-attributes-1

receiver/prometheusreceiver/internal/transaction.go

@@ -74,8 +74,9 @@ type transaction struct {
 var emptyScopeID scopeID
 
 type scopeID struct {
-	name    string
-	version string
+	name      string
+	version   string
+	schemaURL string
 }
 
 func newTransaction(
@@ -431,6 +432,9 @@ func (t *transaction) getMetrics() (pmetric.Metrics, error) {
 				// Otherwise, use the scope that was provided with the metrics.
 				ils.Scope().SetName(scope.name)
 				ils.Scope().SetVersion(scope.version)
+				if scope.schemaURL != "" {
+					ils.SetSchemaUrl(scope.schemaURL)
+				}
 				// If we got an otel_scope_info metric for that scope, get scope
 				// attributes from it.
 				if scopeAttributes, ok := t.scopeAttributes[rKey]; ok {
@@ -472,6 +476,9 @@ func getScopeID(ls labels.Labels) scopeID {
 		if lbl.Name == prometheus.ScopeVersionLabelKey {
 			scope.version = lbl.Value
 		}
+		if lbl.Name == prometheus.ScopeSchemaURLLabelKey {
+			scope.schemaURL = lbl.Value
+		}
 	})
 	return scope
 }
@@ -597,6 +604,10 @@ func (t *transaction) addScopeInfo(key resourceKey, ls labels.Labels) {
 			scope.version = lbl.Value
 			return
 		}
+		if lbl.Name == prometheus.ScopeSchemaURLLabelKey {
+			scope.schemaURL = lbl.Value
+			return
+		}
 		attrs.PutStr(lbl.Name, lbl.Value)
 	})
 	if _, ok := t.scopeAttributes[key]; !ok {

receiver/prometheusreceiver/internal/util.go

@@ -43,7 +43,7 @@ var (
 
 	notUsefulLabelsOther = sortString([]string{
 		model.MetricNameLabel, model.InstanceLabel, model.SchemeLabel,
-		model.MetricsPathLabel, model.JobLabel, prometheus.ScopeNameLabelKey, prometheus.ScopeVersionLabelKey,
+		model.MetricsPathLabel, model.JobLabel, prometheus.ScopeNameLabelKey, prometheus.ScopeVersionLabelKey, prometheus.ScopeSchemaURLLabelKey,
 	})
 	notUsefulLabelsHistogram = sortString(append(notUsefulLabelsOther, model.BucketLabel))
 	notUsefulLabelsSummary   = sortString(append(notUsefulLabelsOther, model.QuantileLabel))

receiver/prometheusreceiver/metrics_receiver_labels_test.go

@@ -825,7 +825,7 @@ func verifyTargetInfoResourceAttributes(t *testing.T, td *testData, rms []pmetri
 const targetInstrumentationScopes = `
 # HELP jvm_memory_bytes_used Used bytes of a given JVM memory area.
 # TYPE jvm_memory_bytes_used gauge
-jvm_memory_bytes_used{area="heap", otel_scope_name="fake.scope.name", otel_scope_version="v0.1.0"} 100
+jvm_memory_bytes_used{area="heap", otel_scope_name="fake.scope.name", otel_scope_version="v0.1.0", otel_scope_schema_url="https://opentelemetry.io/schemas/1.21.0"} 100
 jvm_memory_bytes_used{area="heap", otel_scope_name="scope.with.attributes", otel_scope_version="v1.5.0"} 100
 jvm_memory_bytes_used{area="heap"} 100
 # TYPE otel_scope_info gauge
@@ -858,17 +858,20 @@ func verifyMultipleScopes(t *testing.T, td *testData, rms []pmetric.ResourceMetr
 
 	require.Equal(t, "fake.scope.name", sms.At(0).Scope().Name())
 	require.Equal(t, "v0.1.0", sms.At(0).Scope().Version())
+	require.Equal(t, "https://opentelemetry.io/schemas/1.21.0", sms.At(0).SchemaUrl())
 	require.Equal(t, 0, sms.At(0).Scope().Attributes().Len())
 	require.Equal(t, "github.com/open-telemetry/opentelemetry-collector-contrib/receiver/prometheusreceiver", sms.At(1).Scope().Name())
+	require.Empty(t, sms.At(1).SchemaUrl())
 	require.Equal(t, 0, sms.At(1).Scope().Attributes().Len())
 	require.Equal(t, "scope.with.attributes", sms.At(2).Scope().Name())
 	require.Equal(t, "v1.5.0", sms.At(2).Scope().Version())
+	require.Empty(t, sms.At(2).SchemaUrl())
 	require.Equal(t, 1, sms.At(2).Scope().Attributes().Len())
 	scopeAttrVal, found := sms.At(2).Scope().Attributes().Get("animal")
 	require.True(t, found)
 	require.Equal(t, "bear", scopeAttrVal.Str())
 
-	// Check that otel_scope_name and otel_scope_version are dropped from metric data point attributes
+	// Check that otel_scope_name, otel_scope_version, and otel_scope_schema_url are dropped from metric data point attributes
 	require.Equal(t, 1, sms.At(0).Metrics().Len())
 	metric := sms.At(0).Metrics().At(0)
 	dp := metric.Gauge().DataPoints().At(0)