Logging in via Firebase Email/Password - firebase

Question

I am trying to build a basic web application w/ user authentication via email/password registration using Firebase.
My setup right now includes a main.js file that consists of the following:
var dbRef = new Firebase('https://url.firebaseIO.com');
var authClient = new FirebaseAuthClient(dbRef, function(error, user) {
if (error) {
// an error occurred while attempting login
console.log(error);
} else if (user) {
// user authenticated with Firebase
console.log('User ID: ' + user.id + ', Provider: ' + user.provider);
} else {
// user is logged out
console.log('logged out!');
}
});
function next(){
window.location = 'index.html';
}
function test(){
authClient.login('password', {
email: email,
password: password,
rememberMe: true
},next());
// window.location = 'index.html';
}
I obtain email/password values from a form and login. That works. But as soon as I include a callback function to then redirect them to a new authenticated page, it no longer works. In fact, most of the time I get an "UNKOWN ERROR" response.
When I get to the next page, I am no longer logged in. If I remove the next() function and stay on the same page, it works - even if I then trigger the next function from the console. Is there a different way you are supposed to proceed to another page?
I'm pretty sure there is some sort of communication issue (possibly the login does not get a return before the page is switched?) because if I add a 1s timeout before the next function, it then works. But surely this is not best practice?
Thanks!

Answer 1

Per https://www.firebase.com/docs/security/simple-login-email-password.html, the authClient.login() method does not actually accept a callback, so the problem you're seeing is likely the result of navigating away from the current page before the callback is returned, as you suggested.
I would recommend doing the redirect in the callback you're passing during the instantiation of the auth client. (new FirebaseAuthClient(ref, callback)) and redirect if you detect a logged-in user. This callback will be invoked once upon instantiation with the current authentication state of the user, and then again any time the user's authentication state changes (such as on login or logout).