ValueError: verify_ssl, ssl_context, fingerprint and ssl parameters are mutually exclusive

[brianmedigate]

Describe the bug

This change #8043 is listed in the changelog under "features" https://docs.aiohttp.org/en/stable/changes.html#features, but I think it is a breaking change.

For example, aiobotocore creates a TCPConnector and passes both verify_ssl and ssl, and after upgrading to aiohttp 3.9.2 started to fail with a ValueError because the verify_ssl and ssl parameters are mutually exclusive.

Regardless, aiobotocore needs to stop using the deprecated verify_ssl argument (aio-libs/aiobotocore#882), but in the meantime I doubt you intended 3.9.2 to contain a breaking change in this way.

To Reproduce

from aiobotocore.session import get_session

session = get_session()

async with session.create_client("s3", verify=False):
    pass

Expected behavior

don't raise a ValueError

Logs/tracebacks

venv/lib/python3.8/site-packages/aiobotocore/session.py:24: in __aenter__
    return await self._client.__aenter__()
venv/lib/python3.8/site-packages/aiobotocore/client.py:627: in __aenter__
    await self._endpoint.http_session.__aenter__()
venv/lib/python3.8/site-packages/aiobotocore/httpsession.py:122: in __aenter__
    self._connector = self._create_connector()
venv/lib/python3.8/site-packages/aiobotocore/httpsession.py:111: in <lambda>
    self._create_connector = lambda: aiohttp.TCPConnector(
venv/lib/python3.8/site-packages/aiohttp/connector.py:786: in __init__
    self._ssl = _merge_ssl_params(ssl, verify_ssl, ssl_context, fingerprint)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

ssl = None, verify_ssl = False, ssl_context = None, fingerprint = None

    def _merge_ssl_params(
        ssl: Union["SSLContext", bool, Fingerprint],
        verify_ssl: Optional[bool],
        ssl_context: Optional["SSLContext"],
        fingerprint: Optional[bytes],
    ) -> Union["SSLContext", bool, Fingerprint]:
        if verify_ssl is not None and not verify_ssl:
            warnings.warn(
                "verify_ssl is deprecated, use ssl=False instead",
                DeprecationWarning,
                stacklevel=3,
            )
            if ssl is not True:
>               raise ValueError(
                    "verify_ssl, ssl_context, fingerprint and ssl "
                    "parameters are mutually exclusive"
                )
E               ValueError: verify_ssl, ssl_context, fingerprint and ssl parameters are mutually exclusive

Python Version

$ python --version
Python 3.8.18

aiohttp Version

$ python -m pip show aiohttp
Name: aiohttp
Version: 3.9.2
Summary: Async http client/server framework (asyncio)
Home-page: https://github.com/aio-libs/aiohttp
Author:
Author-email:
License: Apache 2
Location: /home/brianm/repos/medigator/venv/lib/python3.8/site-packages
Requires: aiosignal, async-timeout, attrs, frozenlist, multidict, yarl
Required-by: aiobotocore, aiohttp-basicauth, aiohttp-jinja2, aiomonitor

multidict Version

$ python -m pip show multidict
Name: multidict
Version: 6.0.2
Summary: multidict implementation
Home-page: https://github.com/aio-libs/multidict
Author: Andrew Svetlov
Author-email: andrew.svetlov@gmail.com
License: Apache 2
Location: /home/brianm/repos/medigator/venv/lib/python3.8/site-packages
Requires:
Required-by: aiohttp, async-asgi-testclient, yarl

yarl Version

$ python -m pip show yarl
Name: yarl
Version: 1.7.2
Summary: Yet another URL library
Home-page: https://github.com/aio-libs/yarl/
Author: Andrew Svetlov
Author-email: andrew.svetlov@gmail.com
License: Apache 2
Location: /home/brianm/repos/medigator/venv/lib/python3.8/site-packages
Requires: idna, multidict
Required-by: aio-pika, aiohttp, aiormq

OS

Ubuntu 22.04.3

Related component

Client

Additional context

No response

Code of Conduct

• I agree to follow the aio-libs Code of Conduct

[Dreamsorcerer]

There was code elsewhere to change it from None to True. I've just duplicated it in the merge_ssl_params() function to be safe.

[brianmedigate]

Amazing, thank you @Dreamsorcerer!