Client 请求持续时长问题

[accaolei]

Client 这里，这个时候finish() ，并不真的请求时间，应该在 await res.json() 之后再finish() 吧?

def request(self, method, url, **kwargs):
        headers = self.before(method, url)
        res = self._client.request(method, self.handler_url(url),
                                   headers=headers, **kwargs)
        self._span.set_tag('component', 'http-client')
        self._span.finish()
        return res