[receiver/prometheusremotewrite] Add remaining metric metadata translations as per spec

.chloggen/fix_46984.yaml

@@ -0,0 +1,27 @@
+# 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. receiver/filelog)
+component: receiver/prometheus_remote_write
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add remaining metric metadata translations (Name, Unit) from Prometheus to OTLP as per compatibility spec
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [46984]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# 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: []

receiver/prometheusremotewritereceiver/config.go

@@ -11,6 +11,7 @@ import (
 // Config holds common fields and embedded protocol-specific configurations
 type Config struct {
 	confighttp.ServerConfig `mapstructure:",squash"`
+	TrimMetricSuffixes      bool `mapstructure:"trim_metric_suffixes"`
 }
 
 var _ component.Config = (*Config)(nil)

receiver/prometheusremotewritereceiver/config.schema.yaml

@@ -1,4 +1,7 @@
 description: Config holds common fields and embedded protocol-specific configurations
 type: object
+properties:
+  trim_metric_suffixes:
+    type: boolean
 allOf:
   - $ref: go.opentelemetry.io/collector/config/confighttp.server_config

receiver/prometheusremotewritereceiver/factory.go

@@ -34,6 +34,7 @@ func createDefaultConfig() component.Config {
 		ServerConfig: confighttp.ServerConfig{
 			NetAddr: netAddr,
 		},
+		TrimMetricSuffixes: false,
 	}
 }
 

receiver/prometheusremotewritereceiver/receiver.go

@@ -360,6 +360,27 @@ func (prw *prometheusRemoteWriteReceiver) translateV2(_ context.Context, req *wr
 		unit := req.Symbols[ts.Metadata.UnitRef]
 		description := req.Symbols[ts.Metadata.HelpRef]
 
+		if unit != "" {
+			if unit == "ratio" {
+				unit = "1"
+			} else {
+				unit = strings.ReplaceAll(unit, "_per_", "/")
+				unit = prometheus.UnitWordToUCUM(unit)
+			}
+		}
+
+		if prw.config.TrimMetricSuffixes {
+			metricName = strings.TrimSuffix(metricName, "_total")
+			metricName = strings.TrimSuffix(metricName, "_sum")
+			metricName = strings.TrimSuffix(metricName, "_count")
+			metricName = strings.TrimSuffix(metricName, "_bucket")
+
+			origUnit := req.Symbols[ts.Metadata.UnitRef]
+			if origUnit != "" {
+				metricName = strings.TrimSuffix(metricName, "_"+origUnit)
+			}
+		}
+
 		// Handle histograms separately due to their complex mixed-schema processing
 		if ts.Metadata.Type == writev2.Metadata_METRIC_TYPE_HISTOGRAM ||
 			ts.Metadata.Type == writev2.Metadata_METRIC_TYPE_UNSPECIFIED && len(ts.Histograms) > 0 {

receiver/prometheusremotewritereceiver/receiver_test.go

@@ -579,7 +579,7 @@ func TestTranslateV2(t *testing.T) {
 				// The second metric should have 1 data point.
 				metrics1 := sm1.Metrics().AppendEmpty()
 				metrics1.SetName("test_metric")
-				metrics1.SetUnit("seconds")
+				metrics1.SetUnit("s")
 				metrics1.SetDescription("longer description")
 				metrics1.Metadata().PutStr(prometheus.MetricMetadataTypeKey, "gauge")
 
@@ -595,7 +595,7 @@ func TestTranslateV2(t *testing.T) {
 
 				metrics2 := sm1.Metrics().AppendEmpty()
 				metrics2.SetName("test_metric")
-				metrics2.SetUnit("milliseconds")
+				metrics2.SetUnit("ms")
 				metrics2.SetDescription("small desc")
 				metrics2.Metadata().PutStr(prometheus.MetricMetadataTypeKey, "gauge")