python network_error ai_generated true

aiohttp.client_exceptions.WSServerHandshakeError: Invalid websocket handshake

ID: python/aiohttp-websocket-handshake-error

Also available as: JSON · Markdown · 中文
80%Fix Rate
83%Confidence
0Evidence
2024-11-20First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.10 active — — —
3.11 active — — —

Root Cause

The server does not support WebSocket protocol or the handshake response is malformed.

generic

中文

服务器不支持 WebSocket 协议或握手响应格式错误。

Workarounds

  1. 90% success Verify server WebSocket endpoint and use correct URL scheme (ws:// or wss://) 
    async with session.ws_connect('wss://example.com/ws') as ws:
    async for msg in ws:
  2. 80% success Fall back to HTTP long polling if WebSocket fails 
    try:
    async with session.ws_connect(url) as ws:
        # use websocket
except aiohttp.WSServerHandshakeError:
    # fallback to polling

Dead Ends

Common approaches that don't work:

  1. Using a different WebSocket library without checking server compatibility 60% fail

    The server itself may not support WebSocket, so changing the client library won't help.

  2. Adding custom headers to the handshake request 50% fail

    If the server rejects WebSocket at the protocol level, custom headers won't fix it.