Add tracing package.

pkg/trace/otel.go

@@ -0,0 +1,64 @@
+package trace
+
+import (
+	"context"
+	"vc/pkg/logger"
+	"vc/pkg/model"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
+	"go.opentelemetry.io/otel/sdk/resource"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	semconv "go.opentelemetry.io/otel/semconv/v1.17.0"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type Tracer struct {
+	TP *sdktrace.TracerProvider
+	trace.Tracer
+	log *logger.Log
+}
+
+func newExporter(ctx context.Context, cfg *model.Cfg) (sdktrace.SpanExporter, error) {
+	return otlptracehttp.New(ctx,
+		otlptracehttp.WithEndpoint(cfg.Common.Tracing.Addr),
+		otlptracehttp.WithInsecure(),
+	)
+}
+
+func newTraceProvider(exp sdktrace.SpanExporter, serviceName string) *sdktrace.TracerProvider {
+	return sdktrace.NewTracerProvider(
+		sdktrace.WithBatcher(exp),
+		sdktrace.WithResource(resource.NewWithAttributes(
+			semconv.SchemaURL,
+			semconv.ServiceName(serviceName),
+			attribute.String("mura", "mura"),
+		)),
+	)
+}
+
+// New return a new tracer
+func New(ctx context.Context, cfg *model.Cfg, log *logger.Log, projectName, serviceName string) (*Tracer, error) {
+	exp, err := newExporter(ctx, cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	tracer := &Tracer{
+		TP:  newTraceProvider(exp, projectName),
+		log: log,
+	}
+
+	otel.SetTracerProvider(tracer.TP)
+
+	tracer.Tracer = otel.Tracer("")
+
+	return tracer, nil
+}
+
+// Shutdown shuts down the tracer
+func (t *Tracer) Shutdown(ctx context.Context) error {
+	t.log.Info("Shutting down tracer")
+	return t.TP.Shutdown(ctx)
+}