aiohttp.client_exceptions.ClientConnectorError：无法连接到主机stackoverflow.com:443 ssl：default [连接呼叫失败'151.101.193.69'，443]

问题描述

这是我的代码：

import asyncio
import aiohttp


async def main():
    loop = asyncio.get_event_loop()
    url = "https://stackoverflow.com/"

    async with aiohttp.ClientSession(loop=loop) as session:
        async with session.get(url,timeout=30) as resp:
            print(resp.status)

asyncio.run(main())

如果我在计算机上运行它，一切正常，但是如果我在pythonanywhere上运行，则会出现此错误：

Traceback (most recent call last):
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/connector.py",line 936,in _wrap_create_connection
    return await self._loop.create_connection(*args,**kwargs)  # type: ignore  # noqa
  File "/usr/lib/python3.8/asyncio/base_events.py",line 1017,in create_connection
    raise exceptions[0]
  File "/usr/lib/python3.8/asyncio/base_events.py",line 1002,in create_connection
    sock = await self._connect_sock(
  File "/usr/lib/python3.8/asyncio/base_events.py",line 916,in _connect_sock
    await self.sock_connect(sock,address)
  File "/usr/lib/python3.8/asyncio/selector_events.py",line 485,in sock_connect
    return await fut
  File "/usr/lib/python3.8/asyncio/selector_events.py",line 517,in _sock_connect_cb
    raise OSError(err,f'Connect call failed {address}')
ConnectionRefusedError: [Errno 111] Connect call failed ('151.101.193.69',443)
The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "test_c.py",line 39,in <module>
    asyncio.run(main())
  File "/usr/lib/python3.8/asyncio/runners.py",line 43,in run
    return loop.run_until_complete(main)
  File "/usr/lib/python3.8/asyncio/base_events.py",line 608,in run_until_complete
    return future.result()
  File "test_c.py",line 28,in main
    async with session.get(url,timeout=30) as resp:  #,headers=headers
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/client.py",line 1012,in __aenter__
    self._resp = await self._coro
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/client.py",line 480,in _request
    conn = await self._connector.connect(
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/connector.py",line 523,in connect
    proto = await self._create_connection(req,traces,timeout)
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/connector.py",line 858,in _create_connection
    _,proto = await self._create_direct_connection(
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/connector.py",line 1004,in _create_direct_connection
    raise last_exc
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/connector.py",line 980,in _create_direct_connection
    transp,proto = await self._wrap_create_connection(
  File "/home/0dminnimda/.local/lib/python3.8/site-packages/aiohttp/connector.py",line 943,in _wrap_create_connection
    raise client_error(req.connection_key,exc) from exc
aiohttp.client_exceptions.ClientConnectorError: Cannot connect to host stackoverflow.com:443 ssl:default [Connect call failed ('151.101.193.69',443)]
Unclosed client session
client_session: <aiohttp.client.ClientSession object at 0x7f25a71d1a90>

1-托管上的aiohttp，2-我的计算机上的aiohttp

Name: aiohttp
Version: 3.6.2
Summary: Async http client/server framework (asyncio)
Home-page: https://github.com/aio-libs/aiohttp
Author: Nikolay Kim
Author-email: [e-mail]
License: Apache 2
Location: /home/0dminnimda/.local/lib/python3.8/site-packages
Requires: chardet,async-timeout,multidict,yarl,attrs
Required-by: 

Name: aiohttp
Version: 3.6.2
Summary: Async http client/server framework (asyncio)
Home-page: https://github.com/aio-libs/aiohttp
Author: Nikolay Kim
Author-email: [e-mail]
License: Apache 2
Location: c:\users\asus\appdata\roaming\python\python38\site-packages
Requires: async-timeout,attrs,chardet,multidict
Required-by: 

我很茫然，不是吗？我正在使用python3.8运行两个文件。

我也尝试了其他网址，它们有相同的问题

我需要添加更多详细信息吗？

解决方法

参考help from the forum，我在创建客户端时添加了trust_env = True，现在一切正常。这是新代码：

import asyncio
import aiohttp


async def main():
    loop = asyncio.get_event_loop()
    url = "https://stackoverflow.com/"

    async with aiohttp.ClientSession(loop=loop,trust_env=True) as session:
        async with session.get(url,timeout=30) as resp:
            print(resp.status)

asyncio.run(main())

,

如果您使用带有 python（3.8 或更高版本）和 aiohttp（3.7.4 或更高版本）的 Windows 操作系统
有时，像 ... Cannot connect to host <REQUESTED URL>:443 ssl:default [The parameter is incorrect] 这样的异常的解决方案是：

import sys

...

policy = asyncio.WindowsSelectorEventLoopPolicy()
asyncio.set_event_loop_policy(policy)

asyncio.run(main())

你可以检查你的 Python 版本和操作系统：

import sys

...

if (sys.platform.startswith('win')
        and sys.version_info[0] == 3
        and sys.version_info[1] >= 8):
    policy = asyncio.WindowsSelectorEventLoopPolicy()
    asyncio.set_event_loop_policy(policy)

asyncio.run(main())

here,in issue 4536，一切都有更详细的描述。