python config_error ai_generated true

RuntimeError: 应用启动后无法再添加中间件

RuntimeError: Cannot add middleware after an application has started

ID: python/starlette-middleware-order-matters

其他格式: JSON · Markdown 中文 · English
80%修复率
87%置信度
0证据数
2024-07-11首次发现

版本兼容性

版本状态引入弃用备注
0.30.x active — — —
0.36.x active — — —

根因分析

在ASGI应用开始处理请求后（例如在请求处理函数内部）调用app.add_middleware()。

English

Calling app.add_middleware() after the ASGI application has begun serving requests (e.g. inside a request handler).

generic

解决方案

  1. 97% 成功率 
    app = FastAPI()\napp.add_middleware(CORSMiddleware, allow_origins=['*'])
  2. 90% 成功率 
    app = MyMiddleware(app)

无效尝试

常见但无效的做法:

  1. 85% 失败

    Startup events run after middleware stack is built.

  2. 80% 失败

    Existing routes and state are lost.