python system_error ai_generated true

RuntimeError: Uvicorn worker failed to start

ID: python/fastapi-runtimeerror-uvicorn-worker-failed-to-start

Also available as: JSON · Markdown · 中文
80%Fix Rate
83%Confidence
0Evidence
2024-10-12First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active

Root Cause

Uvicorn encountered an error during startup, often due to missing dependencies or incorrect application import.

generic

中文

Uvicorn 在启动过程中遇到错误,通常是由于缺少依赖项或应用程序导入不正确。

Workarounds

  1. 95% success Ensure correct module path and app instance.
    uvicorn myapp:app --reload
  2. 90% success Check that all dependencies are installed.
    pip install -r requirements.txt

Dead Ends

Common approaches that don't work:

  1. Reinstalling uvicorn without checking Python version. 60% fail

    Uvicorn requires Python 3.7+; older versions may cause startup failure.

  2. Using wrong module path in uvicorn command. 80% fail

    If the module path is incorrect, uvicorn cannot find the application.