python network_error ai_generated true

httpx.ConnectError: All connection attempts failed During handling of the above exception, another exception occurred: httpx.HTTPStatusError: Client error '404 Not Found' for url 'https://api.example.com/v1/users'

ID: python/pytest-httpx-mock-not-matched

Also available as: JSON · Markdown · 中文
80%Fix Rate
84%Confidence
0Evidence
2025-01-15First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
0.21.x active — — —
0.22.x active — — —

Root Cause

respx/httpx mock was registered with a URL pattern that does not match the actual request (trailing slash, query string, or http vs https), so the request falls through to the real network.

generic

中文

respx/httpx mock 注册的 URL 模式与实际请求不匹配（尾部斜杠、查询字符串或 http 与 https），导致请求穿透到真实网络。

Workarounds

  1. 93% success 
    import respx, httpx

@respx.mock
async def test_users():
    respx.get(url__regex=r'/v1/users.*').mock(
        return_value=httpx.Response(200, json={'id': 1})
    )
    async with httpx.AsyncClient(base_url='https://api.example.com') as c:
        r = await c.get('/v1/users')
        assert r.status_code == 200
  2. 88% success 
    respx.get('https://api.example.com/v1/users').mock(...)
# Enable debug:
import logging
logging.basicConfig(level=logging.DEBUG)
# Look for 'No mock matched' in output

Dead Ends

Common approaches that don't work:

  1. 85% fail

    Disabling assertions hides the mismatch but the request still goes to the real network and fails with ConnectError.

  2. 90% fail

    The failure is not a timeout; the URL never matches a registered route so no mock intercepts it.