[Python] How can I use the FastAPI Depends chain asynchronously?

As the title suggests, I want to use FastAPI's Depends to implement role-based authentication control for specific routes.

I have two files. If I write the authentication logic as shown below:

auth.py file


class Authenticator:
async def get_sub(self, token: Annotated[str, Depends(oauth2_scheme)]) -> str:
** asynchronous operation **
return sub

async def get_user(self, sub: Annotated[User, Depends(get_sub)]) -> UserInDB:
sub = await self.get_sub(token)
user = await self.user_db.get_user_by_id(id=id)
if not user:
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="Not register yet")
return user
authenticator = Authenticator()

router.py file


router = APIRouter(prefix="/user", dependencies=[Depends(authenticator.get_user)])



@router.get("/")
async def protected_route(request: Request):
pass


If I write the get_user function in the first file with sub: Annotated[User, Depends(get_sub)], a "self" query parameter appears in the route when I run it, which seems odd. How can I make this asynchronous Depends chain work properly without the "self" issue?

know how asynchronous Depends chain work

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