From 7185f0316aa5da832b4e6319177b70dab39282d1 Mon Sep 17 00:00:00 2001
From: Aleksandr Razumov <ernado@go-faster.org>
Date: Tue, 7 Jan 2025 01:34:30 +0300
Subject: [PATCH] refactor: Telemetry instead of Metrics

---
 app/app.go                       | 11 +++++++++--
 app/profiler.go                  |  2 +-
 app/{metrics.go => telemetry.go} | 29 ++++++++++++++++-------------
 3 files changed, 26 insertions(+), 16 deletions(-)
 rename app/{metrics.go => telemetry.go} (90%)

diff --git a/app/app.go b/app/app.go
index a8865ef..3850f85 100644
--- a/app/app.go
+++ b/app/app.go
@@ -31,12 +31,19 @@ const (
 	watchdogTimeout = shutdownTimeout + time.Second*5
 )
 
+// Go runs f until interrupt.
+func Go(f func(ctx context.Context, t *Telemetry) error, op ...Option) {
+	Run(func(ctx context.Context, _ *zap.Logger, t *Telemetry) error {
+		return f(ctx, t)
+	}, op...)
+}
+
 // Run f until interrupt.
 //
 // If errors.Is(err, ctx.Err()) is valid for returned error, shutdown is considered graceful.
 // Context is cancelled on SIGINT. After watchdogTimeout application is forcefully terminated
 // with exitCodeWatchdog.
-func Run(f func(ctx context.Context, lg *zap.Logger, m *Metrics) error, op ...Option) {
+func Run(f func(ctx context.Context, lg *zap.Logger, m *Telemetry) error, op ...Option) {
 	// Apply options.
 	opts := options{
 		zapConfig:  zap.NewProductionConfig(),
@@ -77,7 +84,7 @@ func Run(f func(ctx context.Context, lg *zap.Logger, m *Metrics) error, op ...Op
 		panic(fmt.Sprintf("failed to get resource: %v", err))
 	}
 
-	m, err := newMetrics(ctx, lg.Named("metrics"), res, opts.meterOptions, opts.tracerOptions, opts.loggerOptions)
+	m, err := newTelemetry(ctx, lg.Named("metrics"), res, opts.meterOptions, opts.tracerOptions, opts.loggerOptions)
 	if err != nil {
 		panic(err)
 	}
diff --git a/app/profiler.go b/app/profiler.go
index e192fc8..25c4dde 100644
--- a/app/profiler.go
+++ b/app/profiler.go
@@ -10,7 +10,7 @@ import (
 	"github.com/go-faster/sdk/profiler"
 )
 
-func (m *Metrics) registerProfiler(mux *http.ServeMux) {
+func (m *Telemetry) registerProfiler(mux *http.ServeMux) {
 	var routes []string
 	if v := os.Getenv("PPROF_ROUTES"); v != "" {
 		routes = strings.Split(v, ",")
diff --git a/app/metrics.go b/app/telemetry.go
similarity index 90%
rename from app/metrics.go
rename to app/telemetry.go
index 25ab93b..cb35910 100644
--- a/app/metrics.go
+++ b/app/telemetry.go
@@ -37,8 +37,11 @@ type httpEndpoint struct {
 	addr     string
 }
 
-// Metrics implement common basic metrics and infrastructure to it.
-type Metrics struct {
+// Deprecated: use Telemetry.
+type Metrics = Telemetry
+
+// Telemetry implement common basic metrics and infrastructure to it.
+type Telemetry struct {
 	lg *zap.Logger
 
 	prom *promClient.Registry
@@ -54,7 +57,7 @@ type Metrics struct {
 	shutdowns []shutdown
 }
 
-func (m *Metrics) registerShutdown(name string, fn func(ctx context.Context) error) {
+func (m *Telemetry) registerShutdown(name string, fn func(ctx context.Context) error) {
 	m.shutdowns = append(m.shutdowns, shutdown{name: name, fn: fn})
 }
 
@@ -63,11 +66,11 @@ type shutdown struct {
 	fn   func(ctx context.Context) error
 }
 
-func (m *Metrics) String() string {
+func (m *Telemetry) String() string {
 	return "metrics"
 }
 
-func (m *Metrics) run(ctx context.Context) error {
+func (m *Telemetry) run(ctx context.Context) error {
 	defer m.lg.Debug("Stopped metrics")
 	wg, ctx := errgroup.WithContext(ctx)
 
@@ -101,7 +104,7 @@ func (m *Metrics) run(ctx context.Context) error {
 	return wg.Wait()
 }
 
-func (m *Metrics) shutdown(ctx context.Context) {
+func (m *Telemetry) shutdown(ctx context.Context) {
 	var wg sync.WaitGroup
 
 	// Launch shutdowns in parallel.
@@ -127,28 +130,28 @@ func (m *Metrics) shutdown(ctx context.Context) {
 	wg.Wait()
 }
 
-func (m *Metrics) MeterProvider() metric.MeterProvider {
+func (m *Telemetry) MeterProvider() metric.MeterProvider {
 	if m.meterProvider == nil {
 		return otel.GetMeterProvider()
 	}
 	return m.meterProvider
 }
 
-func (m *Metrics) TracerProvider() trace.TracerProvider {
+func (m *Telemetry) TracerProvider() trace.TracerProvider {
 	if m.tracerProvider == nil {
 		return otel.GetTracerProvider()
 	}
 	return m.tracerProvider
 }
 
-func (m *Metrics) LoggerProvider() log.LoggerProvider {
+func (m *Telemetry) LoggerProvider() log.LoggerProvider {
 	if m.loggerProvider == nil {
 		return noop.NewLoggerProvider()
 	}
 	return m.loggerProvider
 }
 
-func (m *Metrics) TextMapPropagator() propagation.TextMapPropagator {
+func (m *Telemetry) TextMapPropagator() propagation.TextMapPropagator {
 	return m.propagator
 }
 
@@ -172,21 +175,21 @@ func (z zapErrorHandler) Handle(err error) {
 	z.lg.Error("Error", zap.Error(err))
 }
 
-func newMetrics(
+func newTelemetry(
 	ctx context.Context,
 	lg *zap.Logger,
 	res *resource.Resource,
 	meterOptions []autometer.Option,
 	tracerOptions []autotracer.Option,
 	logsOptions []autologs.Option,
-) (*Metrics, error) {
+) (*Telemetry, error) {
 	{
 		// Setup global OTEL logger and error handler.
 		logger := lg.Named("otel")
 		otel.SetLogger(zapr.NewLogger(logger))
 		otel.SetErrorHandler(zapErrorHandler{lg: logger})
 	}
-	m := &Metrics{
+	m := &Telemetry{
 		lg:       lg,
 		resource: res,
 	}