OpenTelemetry (Node) → Go

gox does not wrap OpenTelemetry — use the official Go SDK. Pair with gox/log for application logs and OTel for traces/metrics.

Libraries

Node.js	Go
@opentelemetry/sdk-node	go.opentelemetry.io/otel/sdk
@opentelemetry/api	go.opentelemetry.io/otel
@opentelemetry/instrumentation-express	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp
@opentelemetry/exporter-trace-otlp-http	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp
prom-client	github.com/prometheus/client_golang

go get go.opentelemetry.io/otel
go get go.opentelemetry.io/otel/sdk
go get go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp

Basic setup

Node.js

const { NodeSDK } = require('@opentelemetry/sdk-node');
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node');

const sdk = new NodeSDK({ instrumentations: [getNodeAutoInstrumentations()] });
sdk.start();

Go

import (
    "context"
    "go.opentelemetry.io/otel"
    "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/v1.26.0"
)

func initTracer(ctx context.Context) (*sdktrace.TracerProvider, error) {
    exp, err := otlptracehttp.New(ctx)
    if err != nil {
        return nil, err
    }
    tp := sdktrace.NewTracerProvider(
        sdktrace.WithBatcher(exp),
        sdktrace.WithResource(resource.NewWithAttributes(
            semconv.SchemaURL,
            semconv.ServiceName("my-service"),
        )),
    )
    otel.SetTracerProvider(tp)
    return tp, nil
}

Instrument gox/http

Wrap the handler or use otelhttp middleware:

import (
    "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
    goxhttp "github.com/sahilkhaire/gox/http"
)

app := goxhttp.New()
// otelhttp works with any net/http handler
instrumented := otelhttp.NewHandler(app, "api")
http.ListenAndServe(":3000", instrumented)

Or trace inside handlers:

tracer := otel.Tracer("my-service")
app.Get("/users", func(c *goxhttp.Ctx) error {
    ctx, span := tracer.Start(c.Request.Context(), "getUsers")
    defer span.End()
    c.Request = c.Request.WithContext(ctx)
    // ...
    return c.JSON(200, users)
})

Logging vs tracing

Concern	Use
Application logs	gox/log (slog)
Request traces	OpenTelemetry
HTTP access logs	gox/http Logger() middleware
Metrics	Prometheus or OTel metrics SDK

Correlate logs with traces by adding trace_id to slog output from the active span context.

Environment

Node.js	Go
OTEL_EXPORTER_OTLP_ENDPOINT	Same env var supported by OTLP exporters
OTEL_SERVICE_NAME	Set via resource.WithAttributes(semconv.ServiceName(...))

Use gox/env to load .env with OTel variables:

env.Load()
endpoint := env.Get("OTEL_EXPORTER_OTLP_ENDPOINT", "http://localhost:4318")

Further reading

• OpenTelemetry Go getting started
• otelhttp instrumentation