firebase onauthstatechanged subscription check code example
Example 1: firebase auth get current user
var user = firebase.auth().currentUser;var name, email, photoUrl, uid, emailVerified;if (user != null) { name = user.displayName; email = user.email; photoUrl = user.photoURL; emailVerified = user.emailVerified; uid = user.uid; // The user's ID, unique to the Firebase project. Do NOT use // this value to authenticate with your backend server, if // you have one. Use User.getToken() instead.}
Example 2: google auth.onstatechange
firebase.auth().onAuthStateChanged(function(user) { if (user) {
// User is signed in.
}
else {
// No user is signed in.
}});