FastAPI : pass session provider through @manager.user_loader

Question

I'm confronted to an issue with fastapi_login. I'm trying to pass my db connection function to the manager user_loader.

I follow this doc : https://fastapi-login.readthedocs.io/advanced_usage/

database.py

def get_db():
    db = SessionLocal()
    try:
        yield db
    except:
        db.close()

users.py

@manager.user_loader(session_provider=database.get_db)
async def get_user(username: str, session_provider) :
    db = session_provider()
    user = db.query(UserDb).filter_by(username=username).first()

    return user

routes.py

@router.post('/login', response_model=UserSchema)
async def login(data: OAuth2PasswordRequestForm = Depends()):
    username = data.username
    password = data.password

    user = await users.get_user(username)

It look like the session_provider is not catched by the @manager. I have the feeling that I respect what that said in the documentation. Here is the guvicorn error I get:

eb_1      | Traceback (most recent call last):
web_1      |   File "/usr/local/lib/python3.9/site-packages/uvicorn/protocols/http/h11_impl.py", line 366, in run_asgi
web_1      |     result = await app(self.scope, self.receive, self.send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/uvicorn/middleware/proxy_headers.py", line 75, in __call__
web_1      |     return await self.app(scope, receive, send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/fastapi/applications.py", line 261, in __call__
web_1      |     await super().__call__(scope, receive, send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/applications.py", line 112, in __call__
web_1      |     await self.middleware_stack(scope, receive, send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/middleware/errors.py", line 181, in __call__
web_1      |     raise exc
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/middleware/errors.py", line 159, in __call__
web_1      |     await self.app(scope, receive, _send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/exceptions.py", line 82, in __call__
web_1      |     raise exc
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/exceptions.py", line 71, in __call__
web_1      |     await self.app(scope, receive, sender)
web_1      |   File "/usr/local/lib/python3.9/site-packages/fastapi/middleware/asyncexitstack.py", line 21, in __call__
web_1      |     raise e
web_1      |   File "/usr/local/lib/python3.9/site-packages/fastapi/middleware/asyncexitstack.py", line 18, in __call__
web_1      |     await self.app(scope, receive, send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/routing.py", line 656, in __call__
web_1      |     await route.handle(scope, receive, send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/routing.py", line 259, in handle
web_1      |     await self.app(scope, receive, send)
web_1      |   File "/usr/local/lib/python3.9/site-packages/starlette/routing.py", line 61, in app
web_1      |     response = await func(request)
web_1      |   File "/usr/local/lib/python3.9/site-packages/fastapi/routing.py", line 227, in app
web_1      |     raw_response = await run_endpoint_function(
web_1      |   File "/usr/local/lib/python3.9/site-packages/fastapi/routing.py", line 160, in run_endpoint_function
web_1      |     return await dependant.call(**values)
web_1      |   File "/code/app/routers/users.py", line 56, in login
web_1      |     user = await lib.users.get_user(username)
web_1      | TypeError: get_user() missing 1 required positional argument: 'session_provider'

Any idea how to deal with this ?

Some references I tried without success :

• https://github.com/MushroomMaula/fastapi_login/issues/61

Actually, I bypass the problem by sending the connection session as parameter of get_user in the route.But I prefer put my connection directly in @manager