How would I redirect after authenticating a user using passportjs? - node.js

Question

I looked in several posts, but I cannot find something that meets my situation.
To login (or signup) with google, you have to go to mydomain.com/login/google
You then, well, login with google, and then the callback is handled on mydomain.com/auth/google
Here is the code responsible for this.
app.get('/login/google', passport.authenticate('google'));
app.get('/auth/google',
passport.authenticate('google', { failureRedirect: '/login', failureMessage: false, session: false, failureFlash: true }),
function(req, res) {
res.redirect('/');
});
Here is where I store the users:
passport.use(new GoogleStrategy({
clientID: no,
clientSecret: definitely not,
callbackURL: 'https://no cuz privacy/auth/google'
},
async function(issuer, profile, cb) {
var user = await User.find({ google: true, googleid: profile.id })
if (!user[0]) {
// The Google account has not logged in to this app before. Create a
// new user record and link it to the Google account.
const newUser = await new User({ username: generateUsername(), google: true, googleid: profile.id, googleProfile: profile })
await newUser.save()
return cb(null, newUser);
} else {
// The Google account has previously logged in to the app. Get the
// user record linked to the Google account and log the user in.
console.log('exists')
return cb(null, newUser);
}
}
));
I think you have to do something with the callback function (cb()) to somehow go to app.get('/auth/google') for the redirect, but, all it does is print either exists or new in the console, spinning forever on the client side. Not sure how to redirect after the code determines either account exists or new account.
Edit: I just want to point out that the cb() function could also be done() too. For example:
function(accessToken, refreshToken, profile, done){
console.log("strategy");
console.log(profile);
console.log(accessToken);
console.log(refreshToken);
done(null, profile);
}
^^ Not my code --> PassportJS in Nodejs never call the callback function ^^