Nodejs Testing Authentication but getting a blank screen in browser - node.js

Question

I finished wiring up my authentication flow by enabling cookies inside my application and then essentially telling passport to use cookies inside my authentication.
To test this out, I added a new route handler inside of my application whose sole purpose is to inspect this req.user property.
This is my services/passport.js file:
const passport = require('passport');
const GoogleStrategy = require('passport-google-oauth20').Strategy;
const mongoose = require('mongoose');
const keys = require('../config/keys');
const User = mongoose.model('users');
passport.serializeUser((user, done) => {
done(null, user.id);
});
passport.deserializeUser((id, done) => {
User.findById(id).then(user => {
done(null, user);
});
});
// passport.use() is a generic register to make Passport
// aware of new strategy
// creates a new instance to authenticate users
passport.use(
new GoogleStrategy(
{
clientID: keys.googleClientID,
clientSecret: keys.googleClientSecret,
callbackURL: '/auth/google/callback'
},
(accessToken, refreshToken, profile, done) => {
User.findOne({ googleId: profile.id }).then(existingUser => {
if (existingUser) {
// we already have a record with given profile id
} else {
// we dont have a user record with this id, make a new record
done(null, existingUser);
new User({ googleId: profile.id })
.save()
.then(user => done(null, user));
}
});
}
)
);
The data is passed to passport which pulls out the id out of the cookie data. The id is then passed on to my deserializeUser function where I am taking that id and turning it into a user model instance and then the whole goal is that the user model instance returned from deserializeUser is added to the request object as req.user and so that new route handler mentioned above has a job of inspecting req.user.
So in my routes/authRoutes.js:
const passport = require('passport');
module.exports = app => {
app.get(
'/auth/google',
passport.authenticate('google', {
scope: ['profile', 'email']
})
);
app.get('/auth/google/callback', passport.authenticate('google'));
app.get('/api/current_user', (req, res) => {
res.send(req.user);
});
};
So this is supposed to test that someone who has already gone through the OAuth flow in theory, can now log back in and we can authenticate that is the same user.
So the expected behavior being that I would once again go through the OAuth flow by visiting localhost:5000/auth/google and then open a separate browser in localhost:5000/api/current_user and be able to see the MongoDB record of that user as json in the browser, but instead I got a blank page and no error in my command line terminal or anywhere else.
What could be the matter here?

Answer 1

You have a minor flaw i've noticed in your if statement:
if (existingUser) {
// we already have a record with given profile id
} else {
// we dont have a user record with this id, make a new record
done(null, existingUser);
new User({ googleId: profile.id })
.save()
.then(user => done(null, user));
}
should be:
if (existingUser) {
// we already have a record with given profile id
done(null, existingUser);
} else {
// we dont have a user record with this id, make a new record
new User({ googleId: profile.id })
.save()
.then(user => done(null, user));
}