observe-server/common/opentelemetry/traces.go

package opentelemetry

import (
	"context"
	extConfig "go-admin/config"

	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
	stdout "go.opentelemetry.io/otel/exporters/stdout/stdouttrace"
	"go.opentelemetry.io/otel/propagation"
	"go.opentelemetry.io/otel/sdk/resource"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
)

func initTracer(res *resource.Resource) (*sdktrace.TracerProvider, error) {
	otelConfig := extConfig.ExtConfig.Otel
	endpoint := otelConfig.Common.Endpoint
	exporter := new(sdktrace.SpanExporter)
	var err error
	if endpoint == "" {
		*exporter, err = stdout.New(stdout.WithPrettyPrint())
	} else {
		*exporter, err = otlptracehttp.New(context.TODO(), otlptracehttp.WithEndpoint(endpoint), otlptracehttp.WithInsecure())
	}
	if err != nil {
		return nil, err
	}
	tp := sdktrace.NewTracerProvider(
		sdktrace.WithResource(res),
		sdktrace.WithSampler(sdktrace.AlwaysSample()),
		sdktrace.WithBatcher(*exporter),
	)
	otel.SetTracerProvider(tp)
	otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))
	return tp, nil
}