使用python中的aiohttp获取多个URL

时间:2018-08-07 11:44:19

标签: python-3.x api web-scraping python-asyncio aiohttp

在先前的question中,用户建议使用以下方法通过aiohttp获取多个网址(API调用):

import asyncio
import aiohttp


url_list = ['https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530396000&before=1530436000', 'https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530436000&before=1530476000']

async def fetch(session, url):
    async with session.get(url) as response:
        return await response.json()['data']


async def fetch_all(session, urls, loop):
    results = await asyncio.gather(*[loop.create_task(fetch(session, url)) for url in urls], return_exceptions= True)
    return results

if __name__=='__main__':
    loop = asyncio.get_event_loop()
    urls = url_list
    with aiohttp.ClientSession(loop=loop) as session:
        htmls = loop.run_until_complete(fetch_all(session, urls, loop))
    print(htmls)

但是,这只会导致返回属性错误:

[AttributeError('__aexit__',), AttributeError('__aexit__',)]

(我启用了该功能,否则它将损坏)。我真的希望这里有人可以提供帮助,仍然很难找到asyncio等资源。返回的数据为json格式。最后,我想将所有json字典放入列表中。

1 个答案:

答案 0 :(得分:3)

工作示例:

import asyncio
import aiohttp
import ssl

url_list = ['https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530396000&before=1530436000',
            'https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530436000&before=1530476000']


async def fetch(session, url):
    async with session.get(url, ssl=ssl.SSLContext()) as response:
        return await response.json()


async def fetch_all(urls, loop):
    async with aiohttp.ClientSession(loop=loop) as session:
        results = await asyncio.gather(*[fetch(session, url) for url in urls], return_exceptions=True)
        return results


if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    urls = url_list
    htmls = loop.run_until_complete(fetch_all(urls, loop))
    print(htmls)