add_middleware causes exceptions to not be raised/handled silently #5173
Description
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Example Code
import uvicorn
from fastapi import FastAPI
from starlette.middleware.base import BaseHTTPMiddleware
app = FastAPI()
@app.get("/info")
def info():
# raises Exception as expected, the traceback is seen in console
raise Exception
private_api = FastAPI()
@private_api.get("/info")
def info():
# exception is handled silently, no traceback is seen in console
raise Exception
app.mount("/private", private_api)
class Middleware(BaseHTTPMiddleware):
async def dispatch(self, request, call_next):
return await call_next(request)
app.add_middleware(Middleware) # when this is removed, the exceptions are raised for all routes
if __name__ == '__main__':
uvicorn.run(app, port=8000)Description
When exceptions are raised on a subapp, the exceptions are not propagated all the way to see in console
In the example code
/info raises an exception and the full stacktrace is seen in console
/private/info does not raise the exception and only INFO: 127.0.0.1:56308 - "GET /info HTTP/1.1" 500 Internal Server Error is shown in console
Operating System
Windows
Operating System Details
No response
FastAPI Version
0.74.0
Python Version
3.8.10
Additional Context
uvicorn==0.17.6