server.js

const express = require('express');
const session = require('express-session');
const MongoDBSession = require('connect-mongodb-session')(session);
const bodyParser = require('body-parser');
const bcrypt = require('bcrypt');
const bcryptjs = require('bcryptjs');
const mongoose = require('mongoose');
const UserModel = require('./models/User');
const router = express.Router();
const userRoutes = require('./routes/user');
const app = express();
const cors = require("cors")
const jwt = require('jsonwebtoken');
const nodemailer = require('nodemailer');
const cookieParser = require("cookie-parser");


const User = require('./middleware/key').user;
const Password = require('./middleware/key').pass;
const db = require('./middleware/key').mongoURI;

mongoose.connect(db, {useNewUrlParser: true, useUnifiedTopology: true, useCreateIndex: true})
    .then(() => console.log('MongoDB Connected'))
    .catch(err => console.log(err));

const store = new MongoDBSession({
    uri: db,
    collection: "mySesions"
})

app.use(session({
    secret: 'ssshhhhh',
    store: store,
    saveUninitialized: false,
    resave: false,
    cookie: {
        expires: 60 * 60 * 24,
    },
}));

app.set('view engine', 'ejs');

// Express body parser
app.use(express.urlencoded({extended: true}));
app.use(bodyParser.json());
app.use(cookieParser());

app.use(
    cors({
        //origin: "https://react-login-ui.herokuapp.com",
        origin: "http://localhost:3000",
        credentials: 'include',
    })
)

app.use("/user", userRoutes);

let transporter = nodemailer.createTransport({
    host: 'smtp.gmail.com',
    port: 587,
    secure: false, // true for 465, false for other ports
    auth: {
        user: User,
        pass: Password
    },
});

app.use((req, res, next) => {
    res.header("Access-Control-Allow-Origin", "*");
    res.header(
        "Access-Control-Allow-Headers",
        "Origin, X-Requested-With, Content-Type, Accept, Authorization"
    );
    if (req.method === "OPTIONS") {
        res.header("Access-Control-Allow-Methods", "PUT, POST, PATCH, DELETE, GET");
        return res.status(200).json({});
    }
    next();
});

app.get("/", (req, res) => {
    res.render("landing");
});

app.use((req, res, next) => {
    const error = new Error("Not found");
    error.status = 404;
    next(error);
});

app.use((error, req, res, next) => {
    res.status(error.status || 500);
    res.json({
        error: {
            message: error.message
        }
    });
});

app.use('/', router);

app.listen(process.env.PORT || 8000, () => {
    console.log(`App Started on PORT ${process.env.PORT || 8000}`)
})