code: func (h *Webhook) ServeHTTP(w http.ResponseWriter, r *http.Request) {
  	var update Update
  	err := json.NewDecoder(r.Body).Decode(&update)
  	if err != nil {
  		h.bot.debug(fmt.Errorf("cannot decode update: %v", err))
  		return
  	}
  	h.dest <- update
  }
docs: // The handler simply reads the update from the body of the requests
  // and writes them to the update channel.