Apply feedback from @mx-psi . Create the sampledLogger the first time using it

Author: antonjim-te

.chloggen/SampledLoggerTelemetry.yaml

@@ -15,7 +15,7 @@ issues: [8134]
 # (Optional) One or more lines of additional information to render under the primary note.
 # These lines will be padded with 2 spaces and then inserted directly into the document.
 # Use pipe (|) for multiline entries.
-subtext: The sampled logger is configured by `LogsSamplingConfig` (`service.telemetry.logs.sampling`).
+subtext: The sampled logger is built from the logger. It is configured by `LogsSamplingConfig` (`service.telemetry.logs.sampling`).
 
 # Optional: The change log or logs in which this entry should be included.
 # e.g. '[user]' or '[user, api]'

component/componenttest/nop_telemetry.go

@@ -17,7 +17,7 @@ import (
 func NewNopTelemetrySettings() component.TelemetrySettings {
 	return component.TelemetrySettings{
 		Logger:         zap.NewNop(),
-		SampledLogger:  zap.NewNop(),
+		SampledLogger:  zap.NewNop,
 		TracerProvider: trace.NewNoopTracerProvider(),
 		MeterProvider:  noop.NewMeterProvider(),
 		MetricsLevel:   configtelemetry.LevelNone,

component/telemetry.go

@@ -17,9 +17,10 @@ type TelemetrySettings struct {
 	// component to be used later as well.
 	Logger *zap.Logger
 
-	// SampledLogger passed to the created component.
+	// SampledLogger is built from the logger. It is passed to the created component.
 	// It will be used to avoid flooding the logs with messages that are repeated frequently.
-	SampledLogger *zap.Logger
+	// It will be built the first time used.
+	SampledLogger func() *zap.Logger
 
 	// TracerProvider that the factory can pass to other instrumented third-party libraries.
 	TracerProvider trace.TracerProvider

exporter/exporterhelper/common.go

@@ -171,7 +171,7 @@ func newBaseExporter(set exporter.CreateSettings, bs *baseSettings, signal compo
 		return nil, err
 	}
 
-	be.qrSender = newQueuedRetrySender(set.ID, signal, bs.queue, bs.RetrySettings, &timeoutSender{cfg: bs.TimeoutSettings}, set.SampledLogger)
+	be.qrSender = newQueuedRetrySender(set.ID, signal, bs.queue, bs.RetrySettings, &timeoutSender{cfg: bs.TimeoutSettings}, set.SampledLogger())
 	be.sender = be.qrSender
 	be.StartFunc = func(ctx context.Context, host component.Host) error {
 		// First start the wrapped exporter.

service/service_test.go

@@ -412,8 +412,8 @@ func TestServiceTelemetryLoggers(t *testing.T) {
 		assert.NoError(t, srv.Shutdown(context.Background()))
 	})
 	assert.NotNil(t, srv.telemetrySettings.Logger)
-	assert.NotNil(t, srv.telemetrySettings.SampledLogger)
-	assert.NotEqual(t, srv.telemetrySettings.Logger, srv.telemetrySettings.SampledLogger)
+	assert.NotNil(t, srv.telemetrySettings.SampledLogger())
+	assert.NotEqual(t, srv.telemetrySettings.Logger, srv.telemetrySettings.SampledLogger())
 }
 
 func assertResourceLabels(t *testing.T, res pcommon.Resource, expectedLabels map[string]labelValue) {

service/telemetry/telemetry.go

@@ -5,6 +5,7 @@ package telemetry // import "go.opentelemetry.io/collector/service/telemetry"
 
 import (
 	"context"
+	"sync"
 	"time"
 
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
@@ -16,8 +17,11 @@ import (
 
 type Telemetry struct {
 	logger         *zap.Logger
-	sampledLogger  *zap.Logger
 	tracerProvider *sdktrace.TracerProvider
+
+	createSampledLogger sync.Once
+	sampledLogger       *zap.Logger
+	samplingCfg         *LogsSamplingConfig
 }
 
 func (t *Telemetry) TracerProvider() trace.TracerProvider {
@@ -28,8 +32,13 @@ func (t *Telemetry) Logger() *zap.Logger {
 	return t.logger
 }
 
-func (t *Telemetry) SampledLogger() *zap.Logger {
-	return t.sampledLogger
+func (t *Telemetry) SampledLogger() func() *zap.Logger {
+	return func() *zap.Logger {
+		t.createSampledLogger.Do(func() {
+			t.sampledLogger = newSampledLogger(t.samplingCfg, t.logger)
+		})
+		return t.sampledLogger
+	}
 }
 
 func (t *Telemetry) Shutdown(ctx context.Context) error {
@@ -50,16 +59,15 @@ func New(_ context.Context, set Settings, cfg Config) (*Telemetry, error) {
 	if err != nil {
 		return nil, err
 	}
-	sampledLogger := newSampledLogger(cfg.Logs.Sampling, logger)
 
 	tp := sdktrace.NewTracerProvider(
 		// needed for supporting the zpages extension
 		sdktrace.WithSampler(alwaysRecord()),
 	)
 	return &Telemetry{
 		logger:         logger,
-		sampledLogger:  sampledLogger,
 		tracerProvider: tp,
+		samplingCfg:    cfg.Logs.Sampling,
 	}, nil
 }