OpenTelemetry cho Go

go get go.opentelemetry.io/otel \  go.opentelemetry.io/otel/sdk \  go.opentelemetry.io/otel/sdk/log \  go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp \  go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp \  go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp \  go.opentelemetry.io/contrib/bridges/otelslog

package mainimport (	"context"	"errors"	"go.opentelemetry.io/otel"	"go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp"	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"	"go.opentelemetry.io/otel/log/global"	"go.opentelemetry.io/otel/propagation"	sdklog "go.opentelemetry.io/otel/sdk/log"	"go.opentelemetry.io/otel/sdk/resource"	sdktrace "go.opentelemetry.io/otel/sdk/trace")func setupOTel(ctx context.Context) (func(context.Context) error, error) {	res, err := resource.New(ctx, resource.WithFromEnv(), resource.WithTelemetrySDK(), resource.WithHost())	if err != nil {		return nil, err	}	traceExp, err := otlptracehttp.New(ctx)	if err != nil {		return nil, err	}	logExp, err := otlploghttp.New(ctx)	if err != nil {		return nil, err	}	tp := sdktrace.NewTracerProvider(sdktrace.WithBatcher(traceExp), sdktrace.WithResource(res))	lp := sdklog.NewLoggerProvider(sdklog.WithProcessor(sdklog.NewBatchProcessor(logExp)), sdklog.WithResource(res))	otel.SetTracerProvider(tp)	otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))	global.SetLoggerProvider(lp)	return func(ctx context.Context) error { return errors.Join(tp.Shutdown(ctx), lp.Shutdown(ctx)) }, nil}

shutdown, err := setupOTel(ctx)if err != nil {	log.Fatal(err)}defer shutdown(context.Background()) // flushes on exitlogger := otelslog.NewLogger("my-service")client := &http.Client{Transport: otelhttp.NewTransport(http.DefaultTransport)}srv := &http.Server{Addr: ":8080", Handler: otelhttp.NewHandler(mux, "server")}// Inside a handler: pass r.Context() so the log line carries the request's span.logger.WarnContext(r.Context(), "payment declined", "order", orderID)