OAuth2 PasswordRequestForm

We should update or appication so that it uses the OAuth2PasswordRequestForm

• First we need to import it

from fastapi.security.oauth2 import OAuth2PasswordRequestForm

• Then we need to update our login route

# Before:
@router.post('/login')
def login(user_credentials: schemas.UserLogin, db: Session = Depends(database.get_db)):

    user = db.query(models.User).filter(models.User.email == user_credentials.email).first()

    if not user:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=f"Invalid Credentials")

    if not utils.verify(user_credentials.password, user.password):
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=f"Invalid Credentials")


# After:
@router.post('/login')

# We're setting up a dependency with OAuth2PasswordRequestForm
def login(user_credentials: OAuth2PasswordRequestForm = Depends(), db: Session = Depends(database.get_db)):

    # We need to make a small change as this form that we are using to get user crenetials stores the email in a varialbe called username
    # {
    #   "username": "something"
    #   "password": "somepass"
    # }
    user = db.query(models.User).filter(models.User.email == user_credentials.username).first()

    if not user:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=f"Invalid Credentials")

    if not utils.verify(user_credentials.password, user.password):
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=f"Invalid Credentials")

• Now that we have updated this with the OAuth2PasswordRequestForm, we no longer send the details in the body of the HTTP Request

• If we do we will get the following error:

{
    "detail": [
        {
            "loc": [
                "body",
                "username"
            ],
            "msg": "field required",
            "type": "value_error.missing"
        },
        {
            "loc": [
                "body",
                "password"
            ],
            "msg": "field required",
            "type": "value_error.missing"
        }
    ]
}

• The values now are expected in the form-data section

• This will return the following data:

{
    "access_token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VyX2lkIjoxLCJleHAiOjE2NjIxMTgyMTJ9.KOlnBfmWsu938veeymniWgRiDNdHhXt7xzRirQLw_VQ",
    "token_type": "bearer"
}