Handle user deletion while being logged in in FAB auth manager

[vincbeck]

Resolves #48724.

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[tirkarthi]

Is it a good idea to change the signature too to User | None for correctness so that mypy can catch other places where None needs to be handled but I guess it will have more effort in changing all functions that use it.

airflow/providers/fab/src/airflow/providers/fab/auth_manager/fab_auth_manager.py

Line 268 in 14788f6

def deserialize_user(self, token: dict[str, Any]) -> User:

[vincbeck]

Is it a good idea to change the signature too to User | None for correctness so that mypy can catch other places where None needs to be handled but I guess it will have more effort in changing all functions that use it.

airflow/providers/fab/src/airflow/providers/fab/auth_manager/fab_auth_manager.py

Line 268 in 14788f6

def deserialize_user(self, token: dict[str, Any]) -> User:

This is a very edge case of FAB auth manager. I am not willing to update the auth manager interface and therefore all auth managers for this very specific edge case very specific to FAB auth manager.

[tirkarthi]

Is it a good idea to change the signature too to User | None for correctness so that mypy can catch other places where None needs to be handled but I guess it will have more effort in changing all functions that use it.

airflow/providers/fab/src/airflow/providers/fab/auth_manager/fab_auth_manager.py

Line 268 in 14788f6

def deserialize_user(self, token: dict[str, Any]) -> User:

This is a very edge case of FAB auth manager. I am not willing to update the auth manager interface and therefore all auth managers for this very specific edge case very specific to FAB auth manager.

Ok, the suggestion and link was to change it in fab auth manager only for deserialize_user .

[vincbeck]

deserialize_user

The issue is, deserialize_user is defined in the auth manager interface BaseAuthManager. So if I change the signature of this method in FAB auth manager, I need to update it in BaseAuthManager as well otherwise mypy will complain. And if I change it there, then all auth managers need to reflect this change. I agree with you, ideally we should update the type to reflect the reality but I do not think this is worth it given this is a very special case

[tirkarthi]

Got it. I didn't know BaseAuthManager also needs to be updated for mypy. Thanks for the clarification.