http-server-main.go

func main() {
	// create server
	mux := http.NewServeMux()

	// wrapped handler for use propagation to extract trace signal from http header to request context
	// it like a middleware
	wrappedHandler := otelhttp.NewHandler(http.HandlerFunc(httpHandler), "http-server")
	mux.Handle("/", wrappedHandler)

	// start server
	port := os.Getenv("PORT")
	log.Debug().Msg("starting server at http://localhost:" + port)
	if err := http.ListenAndServe(":"+port, mux); err != nil {
		log.Panic().Err(err).Msg("server error")
	}
}