异步协程不太了解的话可以去看我上篇博客:https://www.cnblogs.com/Red-Sun/p/16934843.html
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1.requests请求
# -*- coding: utf-8 -*-
# @Time : 2022/12/6 16:03
# @Author : 红后
# @Email : not_enabled@163.com
# @blog : https://www.cnblogs.com/Red-Sun
# @File : 实例1.py
# @Software: PyCharm
import aiohttp, asyncio
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.request("GET", url=url) as response:
return await response.text(encoding='UTF-8')
async def main(): # 主函数用于异步函数的启动
url = 'https://www.baidu.com'
html = await aiohttp_requests(url) # await修饰异步函数
print(html)
if __name__ == '__main__':
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
2.session请求
GET:
# -*- coding: utf-8 -*-
# @Time : 2022/12/6 16:33
# @Author : 红后
# @Email : not_enabled@163.com
# @blog : https://www.cnblogs.com/Red-Sun
# @File : 实例2.py
# @Software: PyCharm
import aiohttp, asyncio
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session: # 声明了一个支持异步的上下文管理器
async with session.get(url) as response:
return await response.text(encoding='UTF-8')
async def main(): # 主函数用于异步函数的启动
url = 'https://www.baidu.com'
html = await aiohttp_requests(url) # await修饰异步函数
print(html)
if __name__ == '__main__':
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
其中aiohttp还有post,put, delete...等一系列请求(PS:一般情况下只需要创建一个session,然后使用这个session执行所有的请求。)
PSOT:传参
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session:
data = {'key': 'value'}
async with session.post(url=url, data=data) as response:
return await response.text(encoding='UTF-8')
PS:这种传参传递的数据将会被转码,如果不想被转码可以直接提交字符串data=str(data)
附:关于session请求数据修改操作
1.cookies
自定义cookies应该放在ClientSession中,而不是session.get()中
async def aiohttp_requests(url): # aiohttp的requests函数
cookies = {'USER_AGENT': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36'}
async with aiohttp.ClientSession(cookies=cookies) as session:
async with session.get(url) as response:
return await response.text(encoding='UTF-8')
2.headers
放在自定义的headers跟正常的requests一样放在session.get()中
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session:
headers = {'USER_AGENT': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36'}
async with session.get(url=url, headers=headers) as response:
return await response.text(encoding='UTF-8')
3.timeout
默认响应时间为5分钟,通过timeout可以重新设定,其放在session.get()中
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session:
async with session.get(url=url, timeout=60) as response:
return await response.text(encoding='UTF-8')
4.proxy
当然代理也是支持的在session.get()中配置
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session:
async with session.get(url=url, proxy="http://some.proxy.com") as response:
return await response.text(encoding='UTF-8')
需要授权的代理
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session:
proxy_auth = aiohttp.BasicAuth('user', 'pass') # 用户,密码
async with session.get(url=url, proxy="http://some.proxy.com", proxy_auth=proxy_auth) as response:
return await response.text(encoding='UTF-8')
或者
async def aiohttp_requests(url): # aiohttp的requests函数
async with aiohttp.ClientSession() as session:
async with session.get(url=url, proxy='http://user:pass@some.proxy.com') as response:
return await response.text(encoding='UTF-8')
报错处理
错误:RuntimeError: Event loop is closed
报错原因是使用了asyncio.run(main())
来运行程序
看到别个大佬的总结是asyncio.run()会自动关闭循环,并且调用_ProactorBasePipeTransport.__del__报错, 而asyncio.run_until_complete()不会。
第一种解决方法换成如下代码运行
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
第二种重写方法以保证run()的运行
from functools import wraps
from asyncio.proactor_events import _ProactorBasePipeTransport
def silence_event_loop_closed(func):
@wraps(func)
def wrapper(self, *args, **kwargs):
try:
return func(self, *args, **kwargs)
except RuntimeError as e:
if str(e) != 'Event loop is closed':
raise
return wrapper
_ProactorBasePipeTransport.__del__ = silence_event_loop_closed(_ProactorBasePipeTransport.__del__)
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