Im using Flutter and Firebase. I am trying to figure out if there is a 'built in' way to detect when a Firebase account has been disabled, so that the Flutter app can react and sign out that user if they are logged in already?

I could accomplish this task by adding a 'isDisabled' property to the users document since I already listen for changes to that doc and if it becomes 'true' then log them out. This would require that two changes are made, the 'isDisabled' is set on user doc and account is marked disabled under Authentication.

It just seemed like there might be a more direct way to accomplish this task.

Solution 1: Doug Stevenson

There is not really a more direct way. Firebase Auth is not "realtime". When an account is disabled, the SDK does not know about it immediately. In fact, the user's auth token will stay valid for up to another hour after the time it was disabled. When the token finally expires, the SDK will no long be able to refresh it, and the user will become signed out. Your code will then see that the user is signed out, and they will not be able to sign in again.