python runtime_error ai_generated true

RuntimeError: Cannot write to closing transport

ID: python/aiohttp-cannot-write-after-response-started

Also available as: JSON · Markdown · 中文
80%Fix Rate
82%Confidence
0Evidence
2024-11-14First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.8+ active — — —
3.9+ active — — —
3.10+ active — — —
3.11+ active — — —

Root Cause

aiohttp server tried to write to a StreamResponse after the client disconnected or the response was already finalized.

generic

中文

客户端断开或响应已完成后，aiohttp 服务器仍尝试向 StreamResponse 写入数据。

Workarounds

  1. 90% success 
    if request.transport is None or request.transport.is_closing():
    return
await resp.write(chunk)
  2. 88% success 
    resp = web.StreamResponse()
await resp.prepare(request)
try:
    async for chunk in source:
        await resp.write(chunk)
except (ConnectionResetError, RuntimeError):
    pass
finally:
    await resp.write_eof()

Dead Ends

Common approaches that don't work:

  1. 70% fail

    Silently drops data and may hide application logic bugs.

  2. 85% fail

    The transport is already closing; timeout is unrelated.