Why isAdmin method in User model does not work?

The isAdmin method in a User model is a common implementation for checking if a user is an administrator or not. However, if this method is not working as expected, there could be several reasons for it. Here are some possible explanations:

Incorrect implementation: The first thing to check is the implementation of the isAdmin method itself. Make sure that it is defined correctly in the User model and that it returns the expected value based on the user's role or permissions. For example, it could look something like this:

class User(AbstractBaseUser, PermissionsMixin):
    # ... other fields and methods

    def is_admin(self):
        return self.is_superuser

Incorrect usage: Another possibility is that the isAdmin method is being called incorrectly or in the wrong context. Make sure that you are calling it on an instance of the User model and that you have loaded all the related data for that user. For example:

user = get_object_or_404(User, id=user_id)
if user.is_admin:
    # do something for admin users

Caching issues: If you are using caching, it could be possible that the cached version of the User object does not reflect the latest changes to the user's role or permissions. In that case, you may need to clear the cache or use a fresh query to get the latest data.
Database errors: If there are any errors in the database, such as missing or corrupted data, it could prevent the isAdmin method from working correctly. Make sure that the database is in good shape and that all the necessary data is present.
Permissions and authentication issues: Finally, it's worth checking if there are any issues with permissions or authentication that could be preventing the isAdmin method from working. For example, if the user is not authenticated or if they do not have the necessary permissions to access the method, it could result in unexpected behavior. Make sure that the user is authenticated and that they have the correct permissions to call the method.