返回请求的结果答案

【问题标题】：Returning the result of request返回请求的结果
【发布时间】：2022-09-24 00:53:22
【问题描述】：

我正在通过在后端使用tornado 来开发请求方法。它应该执行获取请求并进行回调，但是我似乎无法返回响应结果。

例如，如果我返回 response.body，这将打印出插入到 HTTPRequest 方法中的 body 参数，而不是返回响应。

这是我的脚本：


class getToken(tornado.web.RequestHandler):

        def __init__(self,url: str, params: str, headers: dict):
            #super(tornado.web.RequestHandler, self).__init__(*args, **kwargs)
            self._client = tornado.httpclient.AsyncHTTPClient()
            self._url = url
            self._body = params
            self._headers = headers


        def response(response):
            return response.request

        @tornado.gen.coroutine
        def _request(self, callback, request):
            try:
                response = yield self._client.fetch(request)
            except tornado.httpclient.HTTPError as e:
                response = e.response
            raise tornado.gen.Return(
                callback(
                    self.response(
                        response
                        )
                    )
                )
        def get_request(self, callback):
            response =  tornado.httpclient.HTTPRequest(self._url,
                                                        method = \'GET\',
                                                        headers = self._headers,
                                                        body = data)
            print(response.body)
            return self._request(
                            callback, 
                            response)

我使用以下内容运行此脚本：

headers = {
    \'Content-Type\': \'application/x-www-form-urlencoded\',
}
url = \'https://query1.finance.yahoo.com/v8/finance/chart/BOIL.L\'

params = \'region=GB&lang=en-GB&includePrePost=false&interval=2m&useYfid=true&range=1d&corsDomain=uk.finance.yahoo.com&.tsrc=finance\'

r = getToken(url = url, params=params, headers=headers)

print(r.get_request(Future.add_done_callback))

结果：

b\'region=GB&lang=en-GB&includePrePost=false&interval=2m&useYfid=true&range=1d&corsDomain=uk.finance.yahoo.com&.tsrc=finance\'

<Future pending cb=[coroutine.<locals>.wrapper.<locals>.<lambda>() at /Users/usr/yahoo/venv/lib/python3.8/site-packages/tornado/gen.py:251]>

响应应该返回一个字典格式，虽然我有点担心为什么未来是悬而未决的。

标签： python tornado

【解决方案1】：

我设法弄清楚了这一点-代码中有一个小错误。

我们本应该：

@staticmethod
def response(response):
    return response.body

对于response

然后将on_request 替换为async-await 根据tornado 应该使用的方法。

        async def on_request(self, callback, request):
            try:
                response = await self._client.fetch(request)
            except tornado.httpclient.HTTPError as e:
                response = e.response
            return callback(
                    self.response(
                        response
                        )
                    )

最后在循环上添加run 方法会产生我之后的结果。

class getToken(tornado.web.RequestHandler):

        def __init__(self,url: str, params: str, headers: dict):
            #super(tornado.web.RequestHandler, self).__init__(*args, **kwargs)
            self._client = tornado.httpclient.AsyncHTTPClient()
            self._url = url
            self._body = params
            self._headers = headers

        @staticmethod
        def response(response):
            return response.body
            
        async def on_request(self, callback, request):
            try:
                response = await self._client.fetch(request)
            except tornado.httpclient.HTTPError as e:
                response = e.response
            return callback(
                    self.response(
                        response
                        )
                    )
                )
        def get_request(self, callback):
            response = tornado.httpclient.HTTPRequest(
                                                    self._url, 
                                                    headers = self._headers,
                                                    method='GET')

            return self._request(
                        callback, 
                        response)
        #@tornado.gen.coroutine
        def post_request(self, callback):
            if isinstance(self._body, str):
                response =  tornado.httpclient.HTTPRequest(self._url,
                                                        method = 'POST',
                                                        headers = self._headers,
                                                        body = self._body
                                                        )

                return self._request(
                            callback, 
                            response)
            else:
                
                data = f'refresh_token={self._body["refresh_token"]}&client_id={self._body["client_id"]}&client_secret={self._body["client_secret"]}&grant_type=refresh_token'
                response =  tornado.httpclient.HTTPRequest(self._url,
                                                        method = 'POST',
                                                        headers = self._headers,
                                                        body = data)
                print(response.body)
                return self._request(
                            callback, 
                            response)

headers = {
    'Origin': 'https://uk.finance.yahoo.com',
    'Accept': '*/*',
    'Referer': 'https://uk.finance.yahoo.com/quote/%5EFTMC?p=%5EFTMC',
    'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.4 Safari/605.1.15',
}

params = 'region=GB&lang=en-GB&includePrePost=false&interval=2m&useYfid=true&range=1d&corsDomain=uk.finance.yahoo.com&.tsrc=finance'

url = 'https://query1.finance.yahoo.com/v8/finance/chart/%5EFTMC'
async def main(request):
    return await request.get_request(print)

if __name__ == '__main__':
    asyncio.run(main(getToken(url, params, headers)))

结果：

b'{"chart":{"result":[{"meta":{"currency":"GBP","symbol":"^FTMC","exchangeName":"FGI","instrumentType":"INDEX","firstTradeDate":504864000,"regularMarketTime":1663947330,"gmtoffset":3600,"timezone":"BST","exchangeTimezoneName":"Europe/London","regularMarketPrice":17972.69,"chartPreviousClose":18331.69,"previousClose":18331.69,"scale":3,"priceHint":2,"currentTradingPeriod":{"pre":{"timezone":"BST","start":1663913700,"end":1663916400,"gmtoffset":3600},"regular":{"timezone":"BST","start":1663916400,"end":1663947000,"gmtoffset":3600},"post":{"timezone":"BST","start":1663947000,"end":1663949700,"gmtoffset":3600}}

...

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【讨论】：