Firebase Authentication: how to verify user still exists

Question

I am using Firebase Anonymous Authentication.

In case a user has been deleted from the Firebase console, the client still believes the user exists, as it still holds the token.

Each time I start the app, I would like to verify if the user still exists. I found out I can use the FirebaseUser.reload() function.

The documentation says that in case the user's account has been disabled or deleted, the FirebaseAuthInvalidUserException will be thrown: https://firebase.google.com/docs/reference/android/com/google/firebase/auth/FirebaseUser.html#reload()

However this is an asyncronous function, and I am struggling finding out how to catch this exception. Can anyone show me a code sample on how to catch this exception? I have looked all documentation, but I haven't found a sample about this.

@BrunoFerreira that shouldn't matter. I would just like to catch that exception. — Daniele B, Aug 03 '17 at 13:46
The point is that I would like to catch that exception, but I don't know how to do that in an asyncronous function. Can anyone show how to do? — Daniele B, Aug 03 '17 at 13:58

score 3 · Accepted Answer · edited Aug 03 '17 at 14:19

3

Try this:

mFirebaseUser.reload().addOnFailureListener(new OnFailureListener() {
    @Override
    public void onFailure(@NonNull Exception e) {
        if (e instanceof FirebaseAuthInvalidUserException) {
            Log.d(TheApp.LOG_TAG, "user doesn't exist anymore");
            createUser();
        }
    }
});

edited Aug 03 '17 at 14:19

Daniele B

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answered Aug 03 '17 at 14:03

Bruno Ferreira

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great thanks, it works by using `addOnFailureListener` – Daniele B Aug 03 '17 at 14:17

Firebase Authentication: how to verify user still exists

1 Answers1