I just saw a tutorial, where the author although was using shared-ref to store the user name, email etc locally, but he didn't use anything to store currentUser on a flutter app, which was connected to firebase. and hence in splash screen, he used if currentUser != null, then goto Home Screen, and it worked fine on restarting the app. hence to log out, again he used firebaseAuth.signOut() . so, does firebase stores currentUser automatically on the local storage of the app?
2 Answers
Firebase Authentication SDKs store the credentials of the user in local storage, and then restore the user from there when the app restarts/page reloads.
Note that this doesn't always means that currentUser != null will work on app startup/page load, as restoring the credentials requires an asynchronous call to the server and currentUser will be null until that call completes. For the best results listen/respond to authStateChanges as shown in the documentation on authentication state.
I don’t think it’s stored locally in terms of shared preferences/ user defaults. I had an issue where without logging out, but uninstalling and reinstalling the app resulted in the app already knowing who I was. Turns out, it was stored in keychain (on iOS, I don’t know the android counterpart). See this answer for more detail on my particular understanding of how firebase saves the user:
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