Add debug wrapper for all traces components, fix error nil

service/internal/builders/connector.go

@@ -48,7 +48,11 @@ func (b *ConnectorBuilder) CreateTracesToTraces(ctx context.Context, set connect
 	}
 
 	logStabilityLevel(set.Logger, f.TracesToTracesStability())
-	return f.CreateTracesToTraces(ctx, set, cfg, next)
+	conn, err := f.CreateTracesToTraces(ctx, set, cfg, next)
+	if err != nil {
+		return nil, err
+	}
+	return wrapTraces(set.ID, set.TelemetrySettings, conn), nil
 }
 
 // CreateTracesToMetrics creates a Traces connector based on the settings and config.
@@ -67,7 +71,11 @@ func (b *ConnectorBuilder) CreateTracesToMetrics(ctx context.Context, set connec
 	}
 
 	logStabilityLevel(set.Logger, f.TracesToMetricsStability())
-	return f.CreateTracesToMetrics(ctx, set, cfg, next)
+	conn, err := f.CreateTracesToMetrics(ctx, set, cfg, next)
+	if err != nil {
+		return nil, err
+	}
+	return wrapTraces(set.ID, set.TelemetrySettings, conn), nil
 }
 
 // CreateTracesToLogs creates a Traces connector based on the settings and config.
@@ -86,7 +94,11 @@ func (b *ConnectorBuilder) CreateTracesToLogs(ctx context.Context, set connector
 	}
 
 	logStabilityLevel(set.Logger, f.TracesToLogsStability())
-	return f.CreateTracesToLogs(ctx, set, cfg, next)
+	conn, err := f.CreateTracesToLogs(ctx, set, cfg, next)
+	if err != nil {
+		return nil, err
+	}
+	return wrapTraces(set.ID, set.TelemetrySettings, conn), nil
 }
 
 // CreateTracesToProfiles creates a Traces connector based on the settings and config.
@@ -110,7 +122,11 @@ func (b *ConnectorBuilder) CreateTracesToProfiles(ctx context.Context, set conne
 	}
 
 	logStabilityLevel(set.Logger, f.TracesToProfilesStability())
-	return f.CreateTracesToProfiles(ctx, set, cfg, next)
+	conn, err := f.CreateTracesToProfiles(ctx, set, cfg, next)
+	if err != nil {
+		return nil, err
+	}
+	return wrapTraces(set.ID, set.TelemetrySettings, conn), nil
 }
 
 // CreateMetricsToTraces creates a Metrics connector based on the settings and config.

service/internal/builders/connector_test.go

@@ -121,37 +121,38 @@ func TestConnectorBuilder(t *testing.T) {
 			cfgs := map[component.ID]component.Config{tt.id: defaultCfg}
 			b := NewConnector(cfgs, factories)
 
-			t2t, err := b.CreateTracesToTraces(context.Background(), createConnectorSettings(tt.id), tt.nextTraces)
+			set := createConnectorSettings(tt.id)
+			t2t, err := b.CreateTracesToTraces(context.Background(), set, tt.nextTraces)
 			if expectedErr := tt.err(pipeline.SignalTraces, pipeline.SignalTraces); expectedErr != "" {
 				assert.EqualError(t, err, expectedErr)
 				assert.Nil(t, t2t)
 			} else {
 				assert.NoError(t, err)
-				assert.Equal(t, nopConnectorInstance, t2t)
+				assertTracesIsnopConnectorInstance(t, t2t)
 			}
 			t2m, err := b.CreateTracesToMetrics(context.Background(), createConnectorSettings(tt.id), tt.nextMetrics)
 			if expectedErr := tt.err(pipeline.SignalTraces, pipeline.SignalMetrics); expectedErr != "" {
 				assert.EqualError(t, err, expectedErr)
 				assert.Nil(t, t2m)
 			} else {
 				assert.NoError(t, err)
-				assert.Equal(t, nopConnectorInstance, t2m)
+				assertTracesIsnopConnectorInstance(t, t2m)
 			}
 			t2l, err := b.CreateTracesToLogs(context.Background(), createConnectorSettings(tt.id), tt.nextLogs)
 			if expectedErr := tt.err(pipeline.SignalTraces, pipeline.SignalLogs); expectedErr != "" {
 				assert.EqualError(t, err, expectedErr)
 				assert.Nil(t, t2l)
 			} else {
 				assert.NoError(t, err)
-				assert.Equal(t, nopConnectorInstance, t2l)
+				assertTracesIsnopConnectorInstance(t, t2l)
 			}
 			t2p, err := b.CreateTracesToProfiles(context.Background(), createConnectorSettings(tt.id), tt.nextProfiles)
 			if expectedErr := tt.err(pipeline.SignalTraces, componentprofiles.SignalProfiles); expectedErr != "" {
 				assert.EqualError(t, err, expectedErr)
 				assert.Nil(t, t2p)
 			} else {
 				assert.NoError(t, err)
-				assert.Equal(t, nopConnectorInstance, t2p)
+				assertTracesIsnopConnectorInstance(t, t2p)
 			}
 
 			m2t, err := b.CreateMetricsToTraces(context.Background(), createConnectorSettings(tt.id), tt.nextTraces)
@@ -476,6 +477,13 @@ func TestNewNopConnectorConfigsAndFactories(t *testing.T) {
 	assert.IsType(t, profilesToProfiles, bProfilesToProfiles)
 }
 
+func assertTracesIsnopConnectorInstance(t *testing.T, conn connector.Traces) {
+	t.Helper()
+	dt, ok := conn.(*debugTraces)
+	require.True(t, ok)
+	assert.Equal(t, nopConnectorInstance, dt.tc)
+}
+
 var nopConnectorInstance = &nopConnector{
 	Consumer: consumertest.NewNop(),
 }

service/internal/builders/traces.go

@@ -0,0 +1,56 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package builders // import "go.opentelemetry.io/collector/service/internal/builders"
+
+import (
+	"context"
+	"reflect"
+
+	"go.uber.org/zap"
+
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/consumer"
+	"go.opentelemetry.io/collector/pdata/ptrace"
+)
+
+type tracesComponent interface {
+	component.Component
+	consumer.Traces
+}
+
+type debugTraces struct {
+	id  component.ID
+	set component.TelemetrySettings
+	tc  tracesComponent
+}
+
+func (dc *debugTraces) Start(ctx context.Context, host component.Host) error {
+	return dc.tc.Start(ctx, host)
+}
+
+func (dc *debugTraces) Shutdown(ctx context.Context) error {
+	return dc.tc.Shutdown(ctx)
+}
+
+func (dc *debugTraces) Capabilities() consumer.Capabilities {
+	return dc.tc.Capabilities()
+}
+
+func (dc *debugTraces) ConsumeTraces(ctx context.Context, tr ptrace.Traces) error {
+	err := dc.tc.ConsumeTraces(ctx, tr)
+	if err == nil {
+		return nil
+	}
+	val := reflect.ValueOf(err)
+	if val.Kind() == reflect.Ptr && val.IsNil() {
+		dc.set.Logger.Error("nil error that is not nil",
+			zap.String("error_type", val.Type().String()))
+		return nil
+	}
+	return err
+}
+
+func wrapTraces(id component.ID, set component.TelemetrySettings, tc tracesComponent) tracesComponent {
+	return &debugTraces{id: id, set: set, tc: tc}
+}