What is Go and OpenTelemetry for tracing?

Question

Accepted Answer

OpenTelemetry is a **standard** for tracing, metrics, and logging in distributed systems.

```go
import (
    "go.opentelemetry.io/otel"
    "go.opentelemetry.io/otel/trace"
    "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
    "go.opentelemetry.io/otel/sdk/trace"
)

func initTracer() (*trace.TracerProvider, error) {
    exporter, err := otlptracegrpc.New(
        context.Background(),
        otlptracegrpc.WithEndpoint("localhost:4317"),
    )
    if err != nil {
        return nil, err
    }

tp := trace.NewTracerProvider(
        trace.WithBatcher(exporter),
        trace.WithSampler(trace.AlwaysSample()),
    )

otel.SetTracerProvider(tp)
    return tp, nil
}

// Creating a span
func handleRequest(ctx context.Context) error {
    ctx, span := otel.Tracer("my-service").Start(ctx, "handleRequest")
    defer span.End()

// Adding attributes
    span.SetAttributes(
        attribute.String("http.method", "GET"),
        attribute.String("http.url", "/api/users"),
    )

// Child span
    ctx, dbSpan := otel.Tracer("db").Start(ctx, "query")
    result, err := db.QueryContext(ctx, "SELECT * FROM users")
    dbSpan.End()

if err != nil {
        span.RecordError(err)
        span.SetStatus(codes.Error, err.Error())
    }

return err
}

// Automatic HTTP tracing
import "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"

handler := otelhttp.NewHandler(mux, "server")
log.Fatal(http.ListenAndServe(":8080", handler))
```

**Features:**
- Distributed tracing.
- Context propagation.
- Auto-instrumentation.
- Export to Jaeger, Zipkin, Prometheus.

Go: What is Go and OpenTelemetry for tracing?