Httpx AsyncClient Timeout Error

[EWOgthb]

Hi, we had a strange situation with AsyncClient. Here is the deal;
First of all this situation happened at Windows system. So my coworkers who uses Mac didn't get this error.

When I make request directly (not async) it works fine, it's a basic get request so i get response in milliseconds. But when i use AsyncClient it takes too long to get response, we solved this with setting timeout to 30secs but this shouldn't be the solution. Obviously something goes wrong...

I got WSL2 installed btw. Network connection is looks fine, other services work well (more complex requests) and so on...

Here is the error log;

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/anyio/_core/_sockets.py", line 149, in connect_tcp
    addr_obj = ip_address(remote_host)
  File "/usr/local/lib/python3.9/ipaddress.py", line 53, in ip_address
    raise ValueError('%r does not appear to be an IPv4 or IPv6 address' %
ValueError: 'api.codat.io' does not appear to be an IPv4 or IPv6 address

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/httpcore/backends/asyncio.py", line 101, in connect_tcp
    stream: anyio.abc.ByteStream = await anyio.connect_tcp(
  File "/usr/local/lib/python3.9/site-packages/anyio/_core/_sockets.py", line 152, in connect_tcp
    gai_res = await getaddrinfo(target_host, remote_port, family=family,
asyncio.exceptions.CancelledError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/httpcore/_exceptions.py", line 8, in map_exceptions
    yield
  File "/usr/local/lib/python3.9/site-packages/httpcore/backends/asyncio.py", line 101, in connect_tcp
    stream: anyio.abc.ByteStream = await anyio.connect_tcp(
  File "/usr/local/lib/python3.9/site-packages/anyio/_core/_tasks.py", line 103, in __exit__
    raise TimeoutError
TimeoutError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/httpx/_transports/default.py", line 60, in map_httpcore_exceptions
    yield
  File "/usr/local/lib/python3.9/site-packages/httpx/_transports/default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
  File "/usr/local/lib/python3.9/site-packages/httpcore/_async/connection_pool.py", line 253, in handle_async_request
    raise exc
  File "/usr/local/lib/python3.9/site-packages/httpcore/_async/connection_pool.py", line 237, in handle_async_request
    response = await connection.handle_async_request(request)
  File "/usr/local/lib/python3.9/site-packages/httpcore/_async/connection.py", line 86, in handle_async_request
    raise exc
  File "/usr/local/lib/python3.9/site-packages/httpcore/_async/connection.py", line 63, in handle_async_request
    stream = await self._connect(request)
  File "/usr/local/lib/python3.9/site-packages/httpcore/_async/connection.py", line 111, in _connect
    stream = await self._network_backend.connect_tcp(**kwargs)
  File "/usr/local/lib/python3.9/site-packages/httpcore/backends/auto.py", line 23, in connect_tcp
    return await self._backend.connect_tcp(
  File "/usr/local/lib/python3.9/site-packages/httpcore/backends/asyncio.py", line 101, in connect_tcp
    stream: anyio.abc.ByteStream = await anyio.connect_tcp(
  File "/usr/local/lib/python3.9/contextlib.py", line 137, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/usr/local/lib/python3.9/site-packages/httpcore/_exceptions.py", line 12, in map_exceptions
    raise to_exc(exc)
httpcore.ConnectTimeout

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/app/./app/services/base.py", line 101, in request
    response = await client.request(
  File "/usr/local/lib/python3.9/site-packages/httpx/_client.py", line 1506, in request
    return await self.send(request, auth=auth, follow_redirects=follow_redirects)
  File "/usr/local/lib/python3.9/site-packages/httpx/_client.py", line 1593, in send
    response = await self._send_handling_auth(
  File "/usr/local/lib/python3.9/site-packages/httpx/_client.py", line 1621, in _send_handling_auth
    response = await self._send_handling_redirects(
  File "/usr/local/lib/python3.9/site-packages/httpx/_client.py", line 1658, in _send_handling_redirects
    response = await self._send_single_request(request)
  File "/usr/local/lib/python3.9/site-packages/httpx/_client.py", line 1695, in _send_single_request
    response = await transport.handle_async_request(request)
  File "/usr/local/lib/python3.9/site-packages/httpx/_transports/default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
  File "/usr/local/lib/python3.9/contextlib.py", line 137, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/usr/local/lib/python3.9/site-packages/httpx/_transports/default.py", line 77, in map_httpcore_exceptions
    raise mapped_exc(message) from exc
httpx.ConnectTimeout

[tomchristie]

From the ValueError: 'api.codat.io' does not appear to be an IPv4 or IPv6 address error, I'd assume you've got some kind of DNS issue that you're hitting here, perhaps that's only occurring when interacting with your Windows system for some reason.

Does this reproduce reliably for you?
Are you able to observe the same behaviour with both httpx and aiohttp?

[sbor23]

Duplicate of #2167