From df4701370223955887d8d17680fc576595b00934 Mon Sep 17 00:00:00 2001
From: Yang Song <songy23@users.noreply.github.com>
Date: Thu, 6 Feb 2025 21:57:08 -0500
Subject: [PATCH] [OTAGENT-21] respect the FF metricremappingdisabled in
 serializer exporter (#33560)

---
 .../exporter/serializerexporter/exporter.go   |  6 +-
 .../serializerexporter/exporter_test.go       | 59 +++++++++++++++++++
 .../exporter/serializerexporter/go.mod        |  2 +-
 3 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/comp/otelcol/otlp/components/exporter/serializerexporter/exporter.go b/comp/otelcol/otlp/components/exporter/serializerexporter/exporter.go
index f2617bf216d7c..a98e8e37aa02f 100644
--- a/comp/otelcol/otlp/components/exporter/serializerexporter/exporter.go
+++ b/comp/otelcol/otlp/components/exporter/serializerexporter/exporter.go
@@ -16,6 +16,7 @@ import (
 	"github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/attributes"
 	"github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/attributes/source"
 	"github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/metrics"
+	pkgdatadog "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/datadog"
 	datadogconfig "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/datadog/config"
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/exporter/exporterhelper"
@@ -87,7 +88,10 @@ func translatorFromConfig(
 		metrics.WithFallbackSourceProvider(hostGetter),
 		metrics.WithHistogramMode(histogramMode),
 		metrics.WithDeltaTTL(cfg.DeltaTTL),
-		metrics.WithOTelPrefix(),
+	}
+
+	if !pkgdatadog.MetricRemappingDisabledFeatureGate.IsEnabled() {
+		options = append(options, metrics.WithOTelPrefix())
 	}
 
 	if statsIn != nil {
diff --git a/comp/otelcol/otlp/components/exporter/serializerexporter/exporter_test.go b/comp/otelcol/otlp/components/exporter/serializerexporter/exporter_test.go
index b27c5335c8dc2..dd838b535d5eb 100644
--- a/comp/otelcol/otlp/components/exporter/serializerexporter/exporter_test.go
+++ b/comp/otelcol/otlp/components/exporter/serializerexporter/exporter_test.go
@@ -12,10 +12,12 @@ import (
 	"strings"
 	"testing"
 
+	pkgdatadog "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/datadog"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/component/componenttest"
 	"go.opentelemetry.io/collector/exporter/exportertest"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 
 	"github.com/DataDog/datadog-agent/pkg/metrics"
@@ -323,6 +325,63 @@ func Test_ConsumeMetrics_MetricOrigins(t *testing.T) {
 	}
 }
 
+func TestMetricPrefix(t *testing.T) {
+	testMetricPrefixWithFeatureGates(t, false, "datadog_trace_agent_retries", "otelcol_datadog_trace_agent_retries")
+	testMetricPrefixWithFeatureGates(t, false, "system.memory.usage", "otel.system.memory.usage")
+	testMetricPrefixWithFeatureGates(t, false, "process.cpu.utilization", "otel.process.cpu.utilization")
+	testMetricPrefixWithFeatureGates(t, false, "kafka.producer.request-rate", "otel.kafka.producer.request-rate")
+
+	testMetricPrefixWithFeatureGates(t, true, "datadog_trace_agent_retries", "datadog_trace_agent_retries")
+	testMetricPrefixWithFeatureGates(t, true, "system.memory.usage", "system.memory.usage")
+	testMetricPrefixWithFeatureGates(t, true, "process.cpu.utilization", "process.cpu.utilization")
+	testMetricPrefixWithFeatureGates(t, true, "kafka.producer.request-rate", "kafka.producer.request-rate")
+}
+
+func testMetricPrefixWithFeatureGates(t *testing.T, disablePrefix bool, inName string, outName string) {
+	prevVal := pkgdatadog.MetricRemappingDisabledFeatureGate.IsEnabled()
+	require.NoError(t, featuregate.GlobalRegistry().Set(pkgdatadog.MetricRemappingDisabledFeatureGate.ID(), disablePrefix))
+	defer func() {
+		require.NoError(t, featuregate.GlobalRegistry().Set(pkgdatadog.MetricRemappingDisabledFeatureGate.ID(), prevVal))
+	}()
+
+	rec := &metricRecorder{}
+	ctx := context.Background()
+	f := NewFactory(rec, &MockTagEnricher{}, func(context.Context) (string, error) {
+		return "", nil
+	}, nil, nil)
+	cfg := f.CreateDefaultConfig().(*ExporterConfig)
+	exp, err := f.CreateMetrics(
+		ctx,
+		exportertest.NewNopSettings(),
+		cfg,
+	)
+	require.NoError(t, err)
+	require.NoError(t, exp.Start(ctx, componenttest.NewNopHost()))
+
+	md := pmetric.NewMetrics()
+	rms := md.ResourceMetrics()
+	rm := rms.AppendEmpty()
+	ilms := rm.ScopeMetrics()
+	ilm := ilms.AppendEmpty()
+	metricsArray := ilm.Metrics()
+	met := metricsArray.AppendEmpty()
+	met.SetName(inName)
+	met.SetEmptySum()
+	met.Sum().SetAggregationTemporality(pmetric.AggregationTemporalityDelta)
+	dp := met.Sum().DataPoints().AppendEmpty()
+	dp.SetIntValue(100)
+
+	require.NoError(t, exp.ConsumeMetrics(ctx, md))
+	require.NoError(t, exp.Shutdown(ctx))
+
+	for _, serie := range rec.series {
+		if serie.Name == outName {
+			return
+		}
+	}
+	t.Errorf("%s not found in metrics", outName)
+}
+
 func newMetrics(
 	histogramMetricName string,
 	histogramDataPoint pmetric.HistogramDataPoint,
diff --git a/comp/otelcol/otlp/components/exporter/serializerexporter/go.mod b/comp/otelcol/otlp/components/exporter/serializerexporter/go.mod
index 67eceb8a61581..c1bf0f706be37 100644
--- a/comp/otelcol/otlp/components/exporter/serializerexporter/go.mod
+++ b/comp/otelcol/otlp/components/exporter/serializerexporter/go.mod
@@ -238,7 +238,7 @@ require (
 
 require (
 	github.com/hashicorp/go-version v1.7.0 // indirect
-	go.opentelemetry.io/collector/featuregate v1.25.0 // indirect
+	go.opentelemetry.io/collector/featuregate v1.25.0
 )
 
 require (