理解和调试 `asyncio.TimeoutError from None` 错误

我遇到了 aiohttp 的问题，出现以下错误，但不确定修复它的最佳方法：

Traceback (most recent call last):
  File "/app/app/services/file_ingestion_utils.py", line 110, in send_api_request
    async with session.post(url, headers=self.headers, data=payload) as response:
  File "/usr/local/lib/python3.8/site-packages/aiohttp/client.py", line 1117, in __aenter__
    self._resp = await self._coro
  File "/usr/local/lib/python3.8/site-packages/aiohttp/client.py", line 544, in _request
    await resp.start(conn)
  File "/usr/local/lib/python3.8/site-packages/aiohttp/client_reqrep.py", line 905, in start
    self._continue = None
  File "/usr/local/lib/python3.8/site-packages/aiohttp/helpers.py", line 656, in __exit__
    raise asyncio.TimeoutError from None
asyncio.exceptions.TimeoutError

我看到从here https://stackoverflow.com/questions/54132962/why-asyncio-timeouterror-is-raised这些错误可能有点模糊，但我至少想了解至少在我的情况下导致这些错误的原因。我的实现如下所示。

    async def async_request(self, df, entity):

        api_request_records = []
        ...some logic to prepare records...


        @backoff.on_exception(backoff.expo, aiohttp.ClientError, max_tries=2)
        async def send_api_request(payload, session):

            url = <some_url>

            try:
                async with session.post(url, headers=self.headers, data=payload) as response:
                      ...some response handling logic...
                    
            except asyncio.TimeoutError:
                self.logger.exception(f"Asyncio TimeoutError on {url} and payload {payload}")

        async with aiohttp.ClientSession() as session:
            await asyncio.gather(
                *[send_api_request(api_request_record, session)) for api_request_record in api_request_records])

Q1：当长度api_request_records很小，该方法工作正常，但是当它很大时，我更有可能得到 TimeoutError。为什么？

Q2：设置 ClientSession(timeout=...) 参数是这里的秘密，因为根据here https://stackoverflow.com/questions/53049523/how-to-prevent-raise-asyncio-timeouterror-and-continue-the-loop，可能会有帮助吗？但是，我觉得这个响应可能有点过时，因为它指出现在使用 ClientTimeout 对象而不是 int。相关地，根据官方文档here https://docs.aiohttp.org/en/stable/client_reference.html#clienttimeout，默认的 ClientTimeout 似乎已经是无限时间了total=None那么这也适用于 ClientSession 吗？

总的来说，希望得到一些帮助和推荐的方法。谢谢！

From https://docs.aiohttp.org/en/stable/client_quickstart.html#timeouts https://docs.aiohttp.org/en/stable/client_quickstart.html#timeouts

默认情况下，aiohttp 使用总共 300 秒（5 分钟）超时，这意味着 整个操作应在 5 分钟内完成。

所以，

session_timeout = aiohttp.ClientTimeout(total=None)
session = aiohttp.ClientSession(timeout=session_timeout)