func main()

in sampleapp/main.go [41:116]
50 lines of code
3 McCabe index (conditional complexity)

func main() {
	initProvider()

	r := mux.NewRouter()
	r.Use(otelmux.Middleware("my-server"))

	// labels represent additional key-value descriptors that can be bound to a
	// metric observer or recorder.
	commonLabels := []attribute.KeyValue{
		attribute.String("labelA", "chocolate"),
		attribute.String("labelB", "raspberry"),
		attribute.String("labelC", "vanilla"),
	}

	r.HandleFunc("/aws-sdk-call", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

		w.Header().Set("Content-Type", "application/json")
		ctx := r.Context()

		xrayTraceID := getXrayTraceID(trace.SpanFromContext(ctx))
		json := simplejson.New()
		json.Set("traceId", xrayTraceID)
		payload, _ := json.MarshalJSON()

		_, _ = w.Write(payload)

	}))

	r.HandleFunc("/outgoing-http-call", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

		w.Header().Set("Content-Type", "application/json")

		client := http.Client{Transport: otelhttp.NewTransport(http.DefaultTransport)}
		ctx := r.Context()

		xrayTraceID, _ := func(ctx context.Context) (string, error) {

			req, _ := http.NewRequestWithContext(ctx, "GET", "https://aws.amazon.com", nil)

			res, err := client.Do(req)
			if err != nil {
				handleErr(err, "HTTP call to aws.amazon.com failed")
			}

			_, _ = ioutil.ReadAll(res.Body)
			_ = res.Body.Close()

			return getXrayTraceID(trace.SpanFromContext(ctx)), err

		}(ctx)

		ctx, span := tracer.Start(
			ctx,
			"CollectorExporter-Example",
			trace.WithAttributes(commonLabels...))
		defer span.End()

		json := simplejson.New()
		json.Set("traceId", xrayTraceID)
		payload, _ := json.MarshalJSON()

		_, _ = w.Write(payload)

	}))

	http.Handle("/", r)

	// Start server
	address := os.Getenv("LISTEN_ADDRESS")
	if len(address) > 0 {
		_ = http.ListenAndServe(fmt.Sprintf("%s", address), nil)
	} else {
		// Default port 8080
		_ = http.ListenAndServe("localhost:8080", nil)
	}
}