Wrap double export in feature gate

exporter/collector/go.mod

@@ -15,6 +15,7 @@ require (
 	github.com/stretchr/testify v1.8.3
 	github.com/tidwall/wal v1.1.7
 	go.opencensus.io v0.24.0
+	go.opentelemetry.io/collector/featuregate v0.77.0
 	go.opentelemetry.io/collector/pdata v1.0.0-rcv0012
 	go.opentelemetry.io/collector/semconv v0.78.0
 	go.opentelemetry.io/otel v1.16.0

exporter/collector/go.sum

@@ -114,6 +114,8 @@ github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9de
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 go.opencensus.io v0.24.0 h1:y73uSU6J157QMP2kn2r30vwW1A2W2WFwSCGnAVxeaD0=
 go.opencensus.io v0.24.0/go.mod h1:vNK8G9p7aAivkbmorf4v+7Hgx+Zs0yY+0fOtgBfjQKo=
+go.opentelemetry.io/collector/featuregate v0.77.0 h1:m1/IzaXoQh6SgF6CM80vrBOCf5zSJ2GVISfA27fYzGU=
+go.opentelemetry.io/collector/featuregate v0.77.0/go.mod h1:/kVAsGUCyJXIDSgHftCN63QiwAEVHRLX2Kh/S+dqgHY=
 go.opentelemetry.io/collector/pdata v1.0.0-rcv0012 h1:R+cfEUMyLn9Q1QknyQ4QU77pbfc1aJKYEXFHtnwSbCg=
 go.opentelemetry.io/collector/pdata v1.0.0-rcv0012/go.mod h1:rEAKFqc1L03lidKtra/2/dJtI0Hp+JsQxuPEIkj/2Vg=
 go.opentelemetry.io/collector/semconv v0.78.0 h1:kiufXJhRiBkjGXPQPLklknbov9xr8N/HV4P/yoICnHI=

exporter/collector/integrationtest/go.mod

@@ -18,6 +18,7 @@ require (
 	go.opentelemetry.io/collector v0.78.0
 	go.opentelemetry.io/collector/component v0.78.0
 	go.opentelemetry.io/collector/exporter v0.78.0
+	go.opentelemetry.io/collector/featuregate v1.0.0-rcv0012
 	go.opentelemetry.io/collector/pdata v1.0.0-rcv0012
 	go.opentelemetry.io/otel v1.16.0
 	go.opentelemetry.io/otel/sdk v1.16.0
@@ -87,7 +88,6 @@ require (
 	github.com/yusufpapurcu/wmi v1.2.2 // indirect
 	go.opentelemetry.io/collector/confmap v0.78.0 // indirect
 	go.opentelemetry.io/collector/consumer v0.78.0 // indirect
-	go.opentelemetry.io/collector/featuregate v1.0.0-rcv0012 // indirect
 	go.opentelemetry.io/collector/receiver v0.78.0 // indirect
 	go.opentelemetry.io/collector/semconv v0.78.0 // indirect
 	go.opentelemetry.io/contrib/propagators/b3 v1.16.1 // indirect

exporter/collector/integrationtest/metrics_integration_test.go

@@ -26,6 +26,7 @@ import (
 	"github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/collector/internal/integrationtest/testcases"
 	"github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping"
 	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.uber.org/zap"
 

exporter/collector/integrationtest/testcases/testcases_metrics.go

@@ -19,6 +19,7 @@ import (
 	"strings"
 	"time"
 
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
@@ -64,6 +65,10 @@ var MetricsTestCases = []TestCase{
 		OTLPInputFixturePath: "testdata/fixtures/metrics/untyped_prometheus_metrics.json",
 		ExpectFixturePath:    "testdata/fixtures/metrics/untyped_prometheus_metrics_expect.json",
 		SkipForSDK:           true,
+		ConfigureCollector: func(cfg *collector.Config) {
+			//nolint:errcheck
+			featuregate.GlobalRegistry().Set("gcp.untyped_double_export", true)
+		},
 	},
 	{
 		Name:                 "Modified prefix unknown domain",

exporter/collector/metrics.go

@@ -50,6 +50,7 @@ import (
 
 	"go.opencensus.io/plugin/ocgrpc"
 	"go.opencensus.io/stats/view"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 
@@ -140,6 +141,13 @@ const (
 	GCPOpsAgentUntypedMetricKey = "prometheus_untyped_metric"
 )
 
+var untypedDoubleExportFeatureGate = featuregate.GlobalRegistry().MustRegister(
+	"gcp.untyped_double_export",
+	featuregate.StageAlpha,
+	featuregate.WithRegisterFromVersion("v0.77.0"),
+	featuregate.WithRegisterDescription("Enable automatically exporting untyped Prometheus metrics as both gauge and cumulative to GCP."),
+	featuregate.WithRegisterReferenceURL("https://github.com/GoogleCloudPlatform/opentelemetry-operations-go/pull/668"))
+
 type labels map[string]string
 
 func (me *MetricsExporter) Shutdown(ctx context.Context) error {
@@ -1236,29 +1244,31 @@ func (m *metricMapper) gaugePointToTimeSeries(
 
 	// if an untyped prometheus metric from ops agent, double-export as gauge and cumulative
 	// to match GMP exporter behavior. Only for internal use.
-	val, ok := point.Attributes().Get(GCPOpsAgentUntypedMetricKey)
-	if ok && val.AsString() == "true" {
-		metricKind := metricpb.MetricDescriptor_CUMULATIVE
-		value, valueType := m.numberDataPointToValue(point, metricKind, metric.Unit())
-		series = append(series, &monitoringpb.TimeSeries{
-			Resource:   resource,
-			Unit:       metric.Unit(),
-			MetricKind: metricKind,
-			ValueType:  valueType,
-			Points: []*monitoringpb.Point{{
-				Interval: &monitoringpb.TimeInterval{
-					EndTime: timestamppb.New(point.Timestamp().AsTime()),
+	if untypedDoubleExportFeatureGate.IsEnabled() {
+		val, ok := point.Attributes().Get(GCPOpsAgentUntypedMetricKey)
+		if ok && val.AsString() == "true" {
+			metricKind := metricpb.MetricDescriptor_CUMULATIVE
+			value, valueType := m.numberDataPointToValue(point, metricKind, metric.Unit())
+			series = append(series, &monitoringpb.TimeSeries{
+				Resource:   resource,
+				Unit:       metric.Unit(),
+				MetricKind: metricKind,
+				ValueType:  valueType,
+				Points: []*monitoringpb.Point{{
+					Interval: &monitoringpb.TimeInterval{
+						EndTime: timestamppb.New(point.Timestamp().AsTime()),
+					},
+					Value: value,
+				}},
+				Metric: &metricpb.Metric{
+					Type: t,
+					Labels: mergeLabels(
+						attributesToLabels(point.Attributes()),
+						extraLabels,
+					),
 				},
-				Value: value,
-			}},
-			Metric: &metricpb.Metric{
-				Type: t,
-				Labels: mergeLabels(
-					attributesToLabels(point.Attributes()),
-					extraLabels,
-				),
-			},
-		})
+			})
+		}
 	}
 
 	return series

exporter/collector/metrics_test.go

@@ -27,6 +27,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/tidwall/wal"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.uber.org/zap"
@@ -1178,6 +1179,8 @@ func TestGaugePointToTimeSeries(t *testing.T) {
 
 	// Add ops agent untyped prometheus metric attribute
 	// Should double-export as gauge+cumulative and drop untyped metric label
+	err := featuregate.GlobalRegistry().Set("gcp.untyped_double_export", true)
+	assert.NoError(t, err)
 	point.Attributes().PutStr(GCPOpsAgentUntypedMetricKey, "true")
 	tsl = mapper.gaugePointToTimeSeries(mr, extraLabels, metric, gauge, point)
 	assert.Len(t, tsl, 2)