app.js

var express = require('express');
var mongoose = require('mongoose');
var passport = require('passport');
var bodyParser = require('body-parser');
var LocalStrategy = require('passport-local');
var passportLocalMongoose = require('passport-local-mongoose');
// var user = require('./models/user');

mongoose.set('userNewUrlParser', true);
mongoose.set('userFindAndModify', false);
mongoose.set('useCreatrIndex', true);
mongoose.set('useUnifiedTopology', true);
mongoose.set("mongodb://localhost/auth_demo_app");

var app = express();
app.set("view engine", "ejs");
app.use(bodyParser.urlencoded({
    extended
        : true
}));
app.use(require("express-session")({
    secret: "Jay is dev",
    resave: false,
    saveUninitialized: false
}));

app.use(passport.initialize());
app.use(passport.session());

passport.use(new LocalStrategy(User.authenticate()));
passport.serializeUser(Use.serializeUser());
passport.deserializeUser(User.deserializeUser());

app.get("/", function (req, res) {
    res.render("home");
});

app.get("/secret", isLoggedIn, function (req, res) {
    res.render("secret");
});

app.get("/register", function (req, res) {
    res.render("register");
});

app.post("/register", function (req, res) {
    var username = req.body.username;
    var password = req.body.passport;
    User.register(new User({
        username: username
    }),
        password, function (err, user) {
            if (err) {
                console.log(err);
                return res.render("register");
            }

            passport.authenticate("local")(
                req, res, function() {
                    res.render("secret");
                }
            );
        });
});

app.get("/login", function (req, res) {
    res.render("login");
});

app.post("/login", passport.authenticate("local", {
    successRedirect: "/secret", 
    failureRedirect: "/login"
}), function (req, res) {
});

app.get("/logout", function (req, res) {
    req.logout();
    res.redirect("/");
});

function isLoggedIn(req, res, next) {
    if(req.isAuthenticated()) return next();
    res.redirect("/login");
}

var port = process.env.PORT || 3000;
app.listen(port, function () {
    console.log("Server chalu thai gyu bhai!");
});