code: func ClientHandler(w http.ResponseWriter, r *http.Request) {
  	w.Header().Set("Content-Type", "application/javascript")
  	_, err := w.Write(ClientSource)
  	if err != nil {
  		http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
  		w.WriteHeader(http.StatusInternalServerError)
  	}
  }
docs: // ClientHandler is the handler which serves the javascript client-side.
  // It can be used as an alternative of a custom http route to register the client-side javascript code,
  // Use the Server's `ClientSource` field instead to serve the custom code if you changed the default prefix for custom websocket events.