index.js

const express = require('express');
const path = require('path');
const dotenv = require('dotenv');
const mongoose = require('mongoose');
const app = express();
const session = require('express-session');
const flash = require('connect-flash');
const passport = require('passport');
const LocalStrategy = require('passport-local');
const GoogleStrategy = require('passport-google-oauth20').Strategy;
const User = require('./models/user');
const productRoutes = require('./routes/products');
const authRoutes = require('./routes/auth');
const cartRoutes = require('./routes/cart');
const dashRoutes = require('./routes/dashboard');
const paymentRoutes = require('./routes/payment');

dotenv.config();
app.use(express.urlencoded({ extended: true }));
app.set('view engine', 'ejs');
app.set('views', path.join(__dirname, '/views'));
app.use(express.static(path.join(__dirname, '/public')));

mongoose.connect(process.env.MONGODB_URI, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
    useCreateIndex: true,
    useFindAndModify: false
});

// seed DB
// const seed = require('./seedDB');
// seed();

// session and flash messages config
const sessionConfig = {
    secret: process.env.SESSION_SECRET,
    resave: false,
    saveUninitialized: true
};
app.use(session(sessionConfig));
app.use(flash());

// Inint the passport and sessions for storing the users
app.use(passport.initialize());
app.use(passport.session());

// Configuring the passport to use local strategy

passport.use(new LocalStrategy(User.authenticate()));

passport.use(
    new GoogleStrategy(
        {
            clientID: process.env.GOOGLE_CLIENTID,
            clientSecret: process.env.GOOGLE_CLIENTSECRET,
            callbackURL: '/auth/google/redirect'
        },
        (accessToken, refreshToken, profile, done) => {
            // passport callback function
            //check if user already exists in our db with the given profile ID
            User.findOne({
                $or: [
                    {
                        username: profile._json.email
                    },
                    {
                        googleId: profile.id
                    }
                ]
            }).then((currentUser) => {
                if (currentUser) {
                    //if we already have a record with the given profile ID
                    done(null, currentUser);
                } else {
                    //if not, create a new user
                    new User({
                        googleId: profile.id,
                        username: profile._json.email,
                        title: profile.displayName
                    })
                        .save()
                        .then((newUser) => {
                            done(null, newUser);
                        });
                }
            });
        }
    )
);
passport.serializeUser((user, done) => {
    done(null, user.id);
});

passport.deserializeUser((id, done) => {
    User.findById(id).then((user) => {
        done(null, user);
    });
});

app.use((req, res, next) => {
    res.locals.success = req.flash('success');
    res.locals.error = req.flash('error');
    res.locals.currentUser = req.user;
    next();
});

// Routes

app.use(productRoutes);
app.use(authRoutes);
app.use(cartRoutes);
app.use(dashRoutes);
app.use(paymentRoutes);

app.get('/', (req, res) => {
    res.redirect('/products');
});
app.all('*', (req, res) => {
    res.render('404');
});
app.listen(process.env.PORT || 3000, () => {
    console.log('Server running on port 3000.');
});