Example of using youtube API on nodejs with passport

passport-youtube.js

var app = require('express')(),
    passport = require('passport'),
    GoogleStrategy = require('passport-google-oauth').OAuth2Strategy,
    mongoose = require('mongoose'),
    google = require('googleapis'),
    OAuth2 = google.auth.OAuth2,
    session = require('express-session');

var config = {
    clientID: 'CLIENT_ID',
    clientSecret: 'CLIENT_SECRET',
    callbackURL: 'http://localhost:8080/auth/google'
};

var db = mongoose.connect("mongodb://localhost:27017/testDB");

var userSchema = new mongoose.Schema({
    _id: { type: String, unique: true },
    access_token: String,
    refresh_token: String,
    name: String
}, { collection: "user" });

var User = db.model('User', userSchema);

passport.serializeUser(function(user, done) {
    done(null, user._id);
});

passport.deserializeUser(function(id, done) {
    User.findById(id, function(err, user) {
        done(err, user);
    });
});

passport.use(new GoogleStrategy({
        clientID: config.clientID,
        clientSecret: config.clientSecret,
        callbackURL: config.callbackURL
    },
    function(accessToken, refreshToken, profile, done) {

        process.nextTick(function() {

            User.findOne({ _id: profile.id }, function(err, res) {
                if (err)
                    return done(err);
                if (res) {
                    console.log("user exists");
                    return done(null, res);
                } else {
                    console.log("insert user");
                    var user = new User({
                        _id: profile.id,
                        access_token: accessToken,
                        refresh_token: refreshToken,
                        name: profile.displayName
                    });
                    user.save(function(err) {
                        if (err)
                            return done(err);
                        return done(null, user);
                    });
                }
            })
        });
    }
));

function userLogged(req, res, next) {
    if (req.isAuthenticated())
        return next();
    res.redirect('/auth/google');
}

app.use(session({ secret: 'somesecret' }));
app.use(passport.initialize());
app.use(passport.session());

app.get('/auth/google', passport.authenticate('google', {
    scope: ['profile', 'https://www.googleapis.com/auth/youtube.readonly'],
    accessType: 'offline'
}));

app.get('/auth/google/callback',
    passport.authenticate('google', {
        successRedirect: '/profile',
        failureRedirect: '/'
    }));

app.get('/profile', userLogged, function(req, res) {

    console.log(req.user);

    var oauth2Client = new OAuth2(
        config.clientID,
        config.clientSecret,
        config.callbackURL
    );

    oauth2Client.credentials = {
        access_token: req.user.access_token,
        refresh_token: req.user.refresh_token
    };

    google.youtube({
        version: 'v3',
        auth: oauth2Client
    }).subscriptions.list({
        part: 'snippet',
        mine: true,
        headers: {}
    }, function(err, data, response) {
        if (err) {
            console.error('Error: ' + err);
            res.json({
                status: "error"
            });
        }
        if (data) {
            console.log(data);
            res.json({
                status: "ok",
                data: data
            });
        }
        if (response) {
            console.log('Status code: ' + response.statusCode);
        }
    });
});

app.listen(8080)

console.log('go to http://localhost:8080/auth/google')