Rewrote observability tests for exporters to use global func

gcp/observability/observability.go

@@ -64,7 +64,7 @@ func Start(ctx context.Context) error {
 	}
 
 	// Enabling tracing and metrics via OpenCensus
-	if err := startOpenCensus(config, nil); err != nil {
+	if err := startOpenCensus(config); err != nil {
 		return fmt.Errorf("failed to instrument OpenCensus: %v", err)
 	}
 

gcp/observability/observability_test.go

@@ -129,7 +129,6 @@ func (fle *fakeLoggingExporter) Close() error {
 type test struct {
 	t   *testing.T
 	fle *fakeLoggingExporter
-	fe  *fakeOpenCensusExporter
 
 	testServer testgrpc.TestServiceServer // nil means none
 	// srv and srvAddr are set once startServer is called.
@@ -229,8 +228,7 @@ func (te *test) enableOpenCensus() {
 		EnableCloudMonitoring:   true,
 		GlobalTraceSamplingRate: 1.0,
 	}
-	te.fe = &fakeOpenCensusExporter{SeenViews: make(map[string]string), t: te.t}
-	startOpenCensus(config, te.fe)
+	startOpenCensus(config)
 }
 
 func checkEventCommon(t *testing.T, seen *grpclogrecordpb.GrpcLogRecord) {
@@ -783,6 +781,16 @@ func (s) TestNoEnvSet(t *testing.T) {
 func (s) TestOpenCensusIntegration(t *testing.T) {
 	te := newTest(t)
 	defer te.tearDown()
+	fe := &fakeOpenCensusExporter{SeenViews: make(map[string]string), t: te.t}
+
+	defer func(ne func(config *configpb.ObservabilityConfig) (tracingMetricsExporter, error)) {
+		newExporter = ne
+	}(newExporter)
+
+	newExporter = func(config *configpb.ObservabilityConfig) (tracingMetricsExporter, error) {
+		return fe, nil
+	}
+
 	te.enableOpenCensus()
 	te.startServer(&testServer{})
 	tc := testgrpc.NewTestServiceClient(te.clientConn())
@@ -807,17 +815,17 @@ func (s) TestOpenCensusIntegration(t *testing.T) {
 	defer cancel()
 	for ctx.Err() == nil {
 		errs = nil
-		te.fe.mu.RLock()
-		if value := te.fe.SeenViews["grpc.io/client/completed_rpcs"]; value != TypeOpenCensusViewCount {
+		fe.mu.RLock()
+		if value := fe.SeenViews["grpc.io/client/completed_rpcs"]; value != TypeOpenCensusViewCount {
 			errs = append(errs, fmt.Errorf("unexpected type for grpc.io/client/completed_rpcs: %s != %s", value, TypeOpenCensusViewCount))
 		}
-		if value := te.fe.SeenViews["grpc.io/server/completed_rpcs"]; value != TypeOpenCensusViewCount {
+		if value := fe.SeenViews["grpc.io/server/completed_rpcs"]; value != TypeOpenCensusViewCount {
 			errs = append(errs, fmt.Errorf("unexpected type for grpc.io/server/completed_rpcs: %s != %s", value, TypeOpenCensusViewCount))
 		}
-		if te.fe.SeenSpans <= 0 {
-			errs = append(errs, fmt.Errorf("unexpected number of seen spans: %v <= 0", te.fe.SeenSpans))
+		if fe.SeenSpans <= 0 {
+			errs = append(errs, fmt.Errorf("unexpected number of seen spans: %v <= 0", fe.SeenSpans))
 		}
-		te.fe.mu.RUnlock()
+		fe.mu.RUnlock()
 		if len(errs) == 0 {
 			break
 		}

gcp/observability/opencensus.go

@@ -38,26 +38,41 @@ var (
 	defaultMetricsReportingInterval = time.Second * 30
 )
 
+type tracingMetricsExporter interface {
+	trace.Exporter
+	view.Exporter
+}
+
+// globals to stub out in tests
+var newExporter = newStackdriverExporter
+
+func newStackdriverExporter(config *configpb.ObservabilityConfig) (tracingMetricsExporter, error) {
+	// Create the Stackdriver exporter, which is shared between tracing and stats
+	mr := monitoredresource.Autodetect()
+	logger.Infof("Detected MonitoredResource:: %+v", mr)
+	var err error
+	exporter, err := stackdriver.NewExporter(stackdriver.Options{
+		ProjectID:         config.DestinationProjectId,
+		MonitoredResource: mr,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to create Stackdriver exporter: %v", err)
+	}
+	return exporter, nil
+}
+
 // This method accepts config and exporter; the exporter argument is exposed to
 // assist unit testing of the OpenCensus behavior.
-func startOpenCensus(config *configpb.ObservabilityConfig, exporter interface{}) error {
+func startOpenCensus(config *configpb.ObservabilityConfig) error {
 	// If both tracing and metrics are disabled, there's no point inject default
 	// StatsHandler.
 	if config == nil || (!config.EnableCloudTrace && !config.EnableCloudMonitoring) {
 		return nil
 	}
 
-	if exporter == nil {
-		// Create the Stackdriver exporter, which is shared between tracing and stats
-		mr := monitoredresource.Autodetect()
-		logger.Infof("Detected MonitoredResource:: %+v", mr)
-		var err error
-		if exporter, err = stackdriver.NewExporter(stackdriver.Options{
-			ProjectID:         config.DestinationProjectId,
-			MonitoredResource: mr,
-		}); err != nil {
-			return fmt.Errorf("failed to create Stackdriver exporter: %v", err)
-		}
+	exporter, err := newExporter(config)
+	if err != nil {
+		return err
 	}
 
 	var so trace.StartOptions