public function handle(ServerRequestInterface $request, ServerFrame $frame) : ResponseInterface
    {
        /** @noinspection UnnecessaryParenthesesInspection */
        return ($this->callback)($request, $frame);
    }
public function handle(ServerRequestInterface $request, ServerFrame $frame) : ResponseInterface
    {
        /** @noinspection UnnecessaryParenthesesInspection */
        return ($this->callback)($request, $frame);
    }
@param ServerRequestInterface $request
@param ServerFrame            $frame

@return ResponseInterface