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FastAPI · Error

WebSocketException

WebSocketException lets a FastAPI WebSocket endpoint reject a client with a closing code and optional reason. Raise it for client errors such as invalid authentication or invalid data.

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Syntax

WebSocketException(code, reason=None)

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  • WebSocket
  • status
  • Depends
  • Cookie
  • Query
  • FastAPI

Source: Exceptions - HTTPException and WebSocketException. Checked 2026-11-03.