code: func (onewayRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
  	return &http.Response{
  		Status:     "200 OK",
  		StatusCode: http.StatusOK,
  		Body:       ioutil.NopCloser(&bytes.Buffer{}),
  		Request:    req,
  	}, nil
  }
docs: // RoundTrip returns a simple 200 OK response that captures the provided request.