Passport integration

Local authentication

The passport-local module is used to implement a local authentication.

This module lets you authenticate using a username and password in your Node.js applications.

Registering the user :

const passport = require('passport');
const LocalStrategy = require('passport-local').Strategy;

// A named strategy is used since two local strategy are used :
// one for the registration and the other to sign-in
passport.use('localSignup', new LocalStrategy({
    // Overriding defaults expected parameters,
    // which are 'username' and 'password'
    usernameField: 'email',
    passwordField: 'password',
    passReqToCallback: true // allows us to pass back the entire request to the callback    .
},
function(req, email, password, next) {
    // Check in database if user is already registered
    findUserByEmail(email, function(user) {
        // If email already exists, abort registration process and
        // pass 'false' to the callback
        if (user) return next(null, false);
        // Else, we create the user
        else {
            // Password must be hashed !
            let newUser = createUser(email, password);

            newUser.save(function() {
                // Pass the user to the callback
                return next(null, newUser);
            });
        }
    });
});

Logging in the user :

const passport = require('passport');
const LocalStrategy = require('passport-local').Strategy;

passport.use('localSignin', new LocalStrategy({
    usernameField : 'email',
    passwordField : 'password',
},
function(email, password, next) {
    // Find the user
    findUserByEmail(email, function(user) {
        // If user is not found, abort signing in process
        // Custom messages can be provided in the verify callback
        // to give the user more details concerning the failed authentication
        if (!user)
            return next(null, false, {message: 'This e-mail address is not associated with any account.'});
        // Else, we check if password is valid
        else {
            // If password is not correct, abort signing in process
            if (!isPasswordValid(password)) return next(null, false);
            // Else, pass the user to callback
            else return next(null, user);
        }
    });
});

Creating routes :

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

// Sign-in route
// Passport strategies are middlewares
app.post('/login', passport.authenticate('localSignin', {
    successRedirect: '/me',
    failureRedirect: '/login'
});

// Sign-up route
app.post('/register', passport.authenticate('localSignup', {
    successRedirect: '/',
    failureRedirect: '/signup'
});

// Call req.logout() to log out
app.get('/logout', function(req, res) {
    req.logout();
    res.redirect('/');
});

app.listen(3000);

Getting started

Passport must be initialized using passport.initialize() middleware. To use login sessions, passport.session() middleware is required.

Note that passport.serialize() and passport.deserializeUser() methods must be defined. Passport will serialize and deserialize user instances to and from the session

const express = require('express');
const session = require('express-session');
const passport = require('passport');
const cookieParser = require('cookie-parser');
const app = express();

// Required to read cookies
app.use(cookieParser());

passport.serializeUser(function(user, next) {
    // Serialize the user in the session
    next(null, user);
});

passport.deserializeUser(function(user, next) {
    // Use the previously serialized user
        next(null, user);
});

// Configuring express-session middleware
app.use(session({
    secret: 'The cake is a lie',
    resave: true,
    saveUninitialized: true
}));

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

// Starting express server on port 3000
app.listen(3000);

Facebook authentication

The passport-facebook module is used to implement a Facebook authentication. In this example, if the user does not exist on sign-in, he is created.

Implementing strategy :

const passport = require('passport');
const FacebookStrategy = require('passport-facebook').Strategy;

// Strategy is named 'facebook' by default
passport.use({
    clientID: 'yourclientid',
    clientSecret: 'yourclientsecret',
    callbackURL: '/auth/facebook/callback'
},
// Facebook will send a token and user's profile
function(token, refreshToken, profile, next) {
    // Check in database if user is already registered
    findUserByFacebookId(profile.id, function(user) {
        // If user exists, returns his data to callback
        if (user) return next(null, user);
        // Else, we create the user
        else {
            let newUser = createUserFromFacebook(profile, token);

            newUser.save(function() {
                // Pass the user to the callback
                return next(null, newUser);
            });
        }
    });
});

Creating routes :

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

// Authentication route
app.get('/auth/facebook', passport.authenticate('facebook', {
    // Ask Facebook for more permissions
    scope : 'email'
}));

// Called after Facebook has authenticated the user
app.get('/auth/facebook/callback',
    passport.authenticate('facebook', {
        successRedirect : '/me',
        failureRedirect : '/'
}));


//...

app.listen(3000);

Simple Username-Password Authentication

In your routes/index.js

Here user is the model for the userSchema

router.post('/login', function(req, res, next) {
    if (!req.body.username || !req.body.password) {
        return res.status(400).json({
            message: 'Please fill out all fields'
        });
    }

    passport.authenticate('local', function(err, user, info) {
        if (err) {
            console.log("ERROR : " + err);
            return next(err);
        }

        if(user) (
            console.log("User Exists!")
            //All the data of the user can be accessed by user.x
            res.json({"success" : true});
            return;
        } else {
            res.json({"success" : false});
            console.log("Error" + errorResponse());
            return;
        }
    })(req, res, next);
});

Google Passport authentication

We have simple module available in npm for goggle authetication name passport-google-oauth20

Consider the following example In this example have created a folder namely config having the passport.js and google.js file in the root directory. In your app.js include the following

var express = require('express');
var session = require('express-session');
var passport = require('./config/passport'); // path where the passport file placed
var app = express();
passport(app);

// other code to initailize the server , error handle

In the passport.js file in the config folder include the following code

var passport = require  ('passport'),
google = require('./google'),
User = require('./../model/user'); // User is the  mongoose model

module.exports = function(app){
  app.use(passport.initialize());
  app.use(passport.session());
  passport.serializeUser(function(user, done){
      done(null, user);
  });
  passport.deserializeUser(function (user, done) {
     done(null, user);
  });
  google();
};

In the google.js file in the same config folder include following

var passport = require('passport'),
GoogleStrategy = require('passport-google-oauth20').Strategy,
User = require('./../model/user');
module.exports = function () {
passport.use(new GoogleStrategy({
        clientID: 'CLIENT ID',
        clientSecret: 'CLIENT SECRET',
        callbackURL: "http://localhost:3000/auth/google/callback"
    },
    function(accessToken, refreshToken, profile, cb) {
        User.findOne({ googleId : profile.id }, function (err, user) {
            if(err){
                return cb(err, false, {message : err});
            }else {
                if (user != '' && user != null) {
                    return cb(null, user, {message : "User "});
                } else {
                    var username  = profile.displayName.split(' ');
                    var userData = new User({
                        name : profile.displayName,
                        username : username[0],
                        password : username[0],
                        facebookId : '',
                        googleId : profile.id,
                    });
                    // send email to user just in case required to send the newly created
                    // credentails to user for future login without using google login
                    userData.save(function (err, newuser) {
                        if (err) {
                            return cb(null, false, {message : err + " !!! Please try again"});
                        }else{
                            return cb(null, newuser);
                        }
                    });
                }
            }
        });
      }
  ));
};

Here in this example, if user is not in DB then creating a new user in DB for local reference using the field name googleId in user model.

Remarks

Password must always be hashed. A simple way to secure passwords using NodeJS would be to use bcrypt-nodejs module.