Fix live reload infinite loop on uvicorn >= 0.39 #818
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Keep WebSocket handler alive by waiting on receive() instead of returning immediately after accept(). Fixes #817.
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Review these changes at https://app.gitnotebooks.com/AnswerDotAI/fasthtml/pull/818 |
erikgaas
commented
Jan 4, 2026
| async def live_reload_ws(websocket): | ||
| await websocket.accept() | ||
| try: | ||
| while True: await websocket.receive() |
Contributor
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Equivalent to just saying "wait forever until we get a disconnect". This appears to be idiomatic for websockets.
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Thanks @erikgaas :) |
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Summary
Fixes #817 — Live reload enters infinite page reload loop on uvicorn >= 0.39.
The Problem
The
/live-reloadWebSocket handler was returning immediately afteraccept(). In uvicorn 0.39+, this correctly sends a close frame, which triggers the client's reconnect logic and causes an infinite reload loop.The Fix
Keep the WebSocket handler alive by looping on
receive()until the client disconnects.Testing
fast_app(live=True)