Current user with Annotated

[ezeparziale]

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Example Code

CurrentUser = Annotated[User, Depends(get_current_user)]


@router.get("/", status_code=status.HTTP_200_OK)
def get_posts(
    db: Session = Depends(get_db),
    current_user: CurrentUser = None,  # <--- None ?
    commons: CommonsDep = None,
) -> list[PostOut]:
    """
    ### Get post list
    """
    pass

Description

I am testing fastapi ==0.95.0 with annontated feature.
I created

CurrentUser = Annotated[User, Depends(get_current_user)]

But I am using the default value in current_user = None, this is correct?

   ...
    current_user: CurrentUser = None,  # <--- None ?
   ...

Operating System

Windows, macOS

Operating System Details

No response

FastAPI Version

0.95.0

Python Version

3.10.10

Additional Context

No response

[nzig]

Since you specify Depends(get_current_user), current_user will always get the value returned by get_current_user() when get_posts() is called by FastAPI. Therefore, setting the default value with = None will have no effect within FastAPI.

The only case it will have an effect is if you call get_posts() directly in some other code. In that case, if you don't pass a value for current_user, Python will apply the default. Note that this is an uncommon case, since usually only FastAPI calls your handlers and you don't call them yourself as normal functions.

Also as a side note, this is most likely also a type error, unless User is some union type that allows None as a value.