38 lines
1.2 KiB
Python
38 lines
1.2 KiB
Python
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"""
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aiohttp - 异步HTTP网络访问
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异步I/O（异步编程）- 只使用一个线程（单线程）来处理用户请求
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用户请求一旦被接纳，剩下的都是I/O操作，通过多路I/O复用也可以达到并发的效果
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这种做法与多线程相比可以让CPU利用率更高，因为没有线程切换的开销
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Redis/Node.js - 单线程 + 异步I/O
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Celery - 将要执行的耗时间的任务异步化处理
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异步I/O事件循环 - uvloop
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"""
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import asyncio
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import re
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import aiohttp
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async def fetch(session, url):
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async with session.get(url, ssl=False) as resp:
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return await resp.text()
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async def main():
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pattern = re.compile(r'\<title\>(?P<title>.*)\<\/title\>')
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urls = ('https://www.python.org/',
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'https://git-scm.com/',
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'https://www.jd.com/',
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'https://www.taobao.com/',
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'https://www.douban.com/')
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async with aiohttp.ClientSession() as session:
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for url in urls:
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html = await fetch(session, url)
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print(pattern.search(html).group('title'))
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if __name__ == '__main__':
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loop = asyncio.get_event_loop()
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loop.run_until_complete(main())
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loop.close()
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