Use Firebase Admin SDK for PHP with Laravel (token reacquisition)

Sep 8, 2020 PHP Laravel Firebase

#Firebase Admin SDK for PHP doesn’t seem to be able to get tokens automatically

For example, Javascript can be obtained with currentUser.getIdToken () as follows. It is convenient because it automatically updates before the expiration date.

firebase.auth (). currentUser.getIdToken (/ * forceRefresh * / true) .then (function (idToken) {
  // Send token to your backend via HTTPS
  // ...
}) .catch (function (error) {
  // Handle error

The Firebase Admin SDK for PHP didn’t have similar functionality. I don’t want to log in again every time the token expires.


    // If you are not logged in
    if (! Session :: get ('token')) {
      $ signInResult = $ this-> auth-> signInAnonymously ();
      Session :: put ('token', $ signInResult-> idToken ());
      Session :: put ('refresh_token', $ signInResult-> refreshToken ());

    // Token authentication
    try {
      $ auth-> verifyIdToken (Session :: get ('token'));
    } catch (\ Exception $ e) {// It is better to narrow down to ExpiredToken here
      // If it expires, reacquire it using the update token
      $ refresh_token = Session :: get ('refresh_token');
      $ signInResult = $ auth-> signInWithRefreshToken ($ refresh_token);
      Session :: put ('token', $ signInResult-> idToken ());

The flow is as follows.

  1. There is refresh_token in the login result, so save it for a session or something.
  2. When the token expires, an exception will be thrown with verifyIdToken (), so get it again with signInWithRefreshToken ()

Timing when refresh token is changed is not so much, so if you want to use it for the time being, I think that the above will be enough.