code: public function handle(ServerRequestInterface $request, ServerFrame $frame) : ResponseInterface
      {
          $this->errorHandler->setup();
  
          try {
  
              return $frame->next($request);
  
          } catch (\Exception $e) {
  
              $body = $this->errorHandler->handleException($e);
  
              return $frame->responseFactory()->create(500, [], $body);
          }
      }
docs: @param ServerRequestInterface $request
  @param ServerFrame            $frame
  
  @return ResponseInterface