How to check if user is still logged in google?

Question

I am using Google OAuth through Laravel Socialite to authenticate all the users in my web app.

I need the user session to end as soon as possible if user logs out of his google account.

I am trying to set up a middleware that would perform regular checks if user is still signed in with google. But I can't find a way to ask "Is user@example.com still the current user on google?"

I tried to get \Socialite::driver('google')->user() in the middleware but that doesn't seem to work without doing a redirect to google beforehand. I would like this check to be as quick and unobtrusive as possible. It should also work during a background ajax call.

It seems that it would be trivial using the client side authentication as there is gapi.auth2.init().isSignedIn.get(). However, that would mean I have to ask users for two authorizations (server side and client side) which seems wrong.

Looking at the docs at google, I see nothing that would let me check their authentication status apart from reauthenticating. Access token won't expire on logout... Is there a workaround?

Answer 1

It turns out that we can actually use gapi javascript in tandem with Socialite - just use the same client token. I didn't suspect that I will just get all the info without logging in separately for browser session, but it works.

I added the following code to the end of my master blade template to check state for authorized users.

@auth
<script>
    var currentUserEmail = '{{Auth::user()->email}}';  // user "sameness" criterion
    var googleClientId = '{{env('GOOGLE_ID')}}';  // the same oauth client id
</script>
<script src="https://apis.google.com/js/platform.js"></script>
<script src="{{mix('js/checkGoogleAuth.js')}}"></script>
@endauth

The script checkGoogleAuth is a simple then, I copied the google tutorial and shortened it:

var auth2; // The Sign-In object.
var googleUser; // The current user.

/**
 * Initializes Signin v2 and sets up listeners.
 */
var initSigninV2 = function() {
  auth2 = gapi.auth2.init({
      client_id: googleClientId,
      scope: 'profile'
  });

  // Listen for sign-in state changes.
  auth2.isSignedIn.listen(checkState);
  auth2.currentUser.listen(checkState);
};

var checkState = function (user) {
    //if signed out or changed user
    if (!auth2.isSignedIn.get() || currentUserEmail != auth2.currentUser.get().getBasicProfile().getEmail())
        $('.logout-username').click();  //click logout button
};

gapi.load('auth2', initSigninV2);  //launch it

I hope it helps someone else as well!