app.js

//jshint esversion:6

require('dotenv').config();
const express = require("express");
const bodyParser = require("body-parser");
const ejs = require("ejs");
const mongoose = require('mongoose');
const session = require('express-session');
const passport = require('passport');
const passportLocalMongoose = require('passport-local-mongoose');
const GoogleStrategy = require('passport-google-oauth20').Strategy;
const findOrCreate = require('mongoose-findorcreate');


const app = express();

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

app.use(bodyParser.urlencoded({extended: true}));
app.use(express.static("public"));

// Initialize Session package
app.use(session({
  secret: process.env.SECRET,
  resave: false,
  saveUninitialized: false
}));

// Initialize Passport
app.use(passport.initialize()); // Use Passport
app.use(passport.session()); // Use the session package of Passport

// Connect to Mongo database
mongoose.connect("mongodb://localhost:27017/userDB", {useNewUrlParser: true});
mongoose.set("useCreateIndex", true); // for  "collection.ensureIndex is deprecated" warning

// Create Schema
const userSchema = new mongoose.Schema ({
  email: String,
  password: String,
  googleId: String,
  secret: String
});

// Enable Schema for Passport
userSchema.plugin(passportLocalMongoose);
userSchema.plugin(findOrCreate);

// Setup Model
const User = mongoose.model("User", userSchema);

// Passport Local configuration
passport.use(User.createStrategy()); // Create local login stragety

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: process.env.GOOGLE_CLIENT_ID,
    clientSecret: process.env.GOOGLE_CLIENT_SECRET,
    callbackURL: "http://localhost:3000/auth/google/secrets",
    userProfileURL: "https://www.googleapis.com/oauth2/v3/userinfo" // to handle Google+ shutdown
  },
  function(accessToken, refreshToken, profile, cb) {
    console.log(profile);
    User.findOrCreate({ googleId: profile.id }, function (err, user) {
      return cb(err, user);
    });
  }
));

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

app.get("/auth/google",
  passport.authenticate("google", { scope: ["profile"] })); // Use Passport to authenticate the user using the Google strategy, using the Google user's profile

app.get("/auth/google/secrets",
  passport.authenticate("google", { failureRedirect: "/login" }),
  function(req, res) {
    // Successful authentication, redirect home.
    res.redirect("/secrets");
  });

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

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

app.get("/secrets", function(req,res){
  if (req.isAuthenticated()){
    User.find({"secret":{$ne:null}}, function(err, foundUsers){ // Find all users who have a secret value (Not Equal to null)
      if (err){
        console.log(err);
      } else {
        if (foundUsers){
          res.render("secrets", {usersWithSecrets: foundUsers});
        }
      }
    });
  } else {
    res.redirect("/login");
  }
});

app.get("/submit", function(req,res){
  if (req.isAuthenticated()){
    res.render("submit");
  } else {
    res.redirect("/login");
  }
});

app.post("/submit", function(req,res){
  const submittedSecret = req.body.secret;

  // Find the user and save the secret to their document
  User.findById(req.user.id, function(err, foundUser){
    if (err){
      console.log(err);
    } else {
        if (foundUser){
          foundUser.secret = submittedSecret;
          foundUser.save(function(){
            res.redirect("/secrets");
          });
        }
    }
  });
});

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

app.post("/register", function(req,res){
  User.register({username: req.body.username}, req.body.password, function(err, user){
    if (err) {
      console.log(err);
      res.redirect("/register");
    } else {
      passport.authenticate("local")(req, res, function(){
        res.redirect("/secrets");
      });
    }
  });
});

app.post("/login", function(req, res){
  const user = new User({
    username: req.body.username,
    password: req.body.password
  });

  req.login(user, function(err){
    if (err){
      console.log(err);
    } else {
      passport.authenticate("local")(req, res, function(){
        res.redirect("/secrets");
      });
    }
  });
});


///////////////////// Start Server /////////////////////
app.listen(3000, function() {
  console.log("Server started on port 3000");
});