code: function onMessage($client_id, $data) {
          if (!is_null($callback = $_SESSION['lock'])) {
              is_callable($callback) && $callback($client_id, $data);
              return;
          }
          $path = $method = null;
          if (is_callable($callback = $this->_on_business_message))
              $this->_router->requestData = $callback($client_id, $data, $path, $method);
          $this->_router->client_id = $client_id;
          $this->_router->locate($path ?? [], $method ?? Router::DEFAULT_METHOD);
      }
docs: 收到请求回调
  
  @param string $client_id
  @param string $data