minor fixes

pkg/otlp/metrics/kafka_mapping.go

@@ -6,6 +6,18 @@ import (
 	"go.opentelemetry.io/collector/pdata/pmetric"
 )
 
+// kafkaMetricsToRename is a map of kafka metrics that should be renamed.
+var kafkaMetricsToRename = map[string]bool{
+	"kafka.producer.request-rate":        true,
+	"kafka.producer.response-rate":       true,
+	"kafka.producer.request-latency-avg": true,
+	"kafka.consumer.fetch-size-avg":      true,
+	"kafka.producer.compression-rate":    true,
+	"kafka.producer.record-retry-rate":   true,
+	"kafka.producer.record-send-rate":    true,
+	"kafka.producer.record-error-rate":   true,
+}
+
 // Note: `-` get converted into `_` which will result in some OTel and DD metric
 // having the same name. In order to prevent duplicate stats, prepend by `otel.`
 // in these cases.
@@ -430,8 +442,7 @@ func remapJvmMetrics(all pmetric.MetricSlice, m pmetric.Metric) {
 
 // renameKafkaMetrics renames otel kafka metrics to avoid conflicts with DD metrics.
 func renameKafkaMetrics(m pmetric.Metric) {
-	switch m.Name() {
-	case "kafka.producer.request-rate", "kafka.producer.response-rate", "kafka.producer.request-latency-avg", "kafka.consumer.fetch-size-avg", "kafka.producer.compression-rate", "kafka.producer.record-retry-rate", "kafka.producer.record-send-rate", "kafka.producer.record-error-rate":
+	if _, ok := kafkaMetricsToRename[m.Name()]; ok {
 		m.SetName("otel." + m.Name())
 	}
 }

pkg/otlp/metrics/metrics_remapping_test.go

@@ -787,16 +787,16 @@ func TestRemapAndRenameMetrics(t *testing.T) {
 		remapMetrics(dest, tt.in)
 		// Ensure remapMetrics does not add the otel.* prefix to the metric name
 		if checkprefix {
-			require.False(t, strings.HasPrefix(tt.in.Name(), "otel."), "system.* and process.*  and a subset of kafka metrics need to be prepended with the otel.* namespace")
-		}
-		require.Equal(t, dest.Len()-lena, len(tt.out), "unexpected number of metrics added")
-		for i, out := range tt.out {
-			assert.NoError(t, pmetrictest.CompareMetric(out, dest.At(dest.Len()-len(tt.out)+i)))
+			require.False(t, strings.HasPrefix(tt.in.Name(), "otel."), "remapMetrics should not add the otel.* prefix to the metric name, it should only compute Datadog metrics")
 		}
 		renameMetrics(tt.in)
 		if checkprefix {
 			require.True(t, strings.HasPrefix(tt.in.Name(), "otel."), "system.* and process.*  and a subset of kafka metrics need to be prepended with the otel.* namespace")
 		}
+		require.Equal(t, dest.Len()-lena, len(tt.out), "unexpected number of metrics added")
+		for i, out := range tt.out {
+			assert.NoError(t, pmetrictest.CompareMetric(out, dest.At(dest.Len()-len(tt.out)+i)))
+		}
 	}
 
 }