code: public function onRequest(Client $client, ServerRequestInterface $request, ResponseInterface $response): ResponseInterface
      {
          return $this->handle($request);
      }
docs: Decorator for handle method, used by server instance.
  @see Application::handle()
  @see Server::addListener()
  
  @param ResponseInterface $response
  @param Client $client
  @param ServerRequestInterface $request
  @return ResponseInterface