server.js

'use strict';

require('dotenv').config();
var path = require('path');
var fs = require('fs');

var express = require('express');
var session = require('express-session');
var passport = require('passport');
var saml = require('passport-saml').Strategy;

var bodyParser = require('body-parser');

var userProfile;
var app = express();

app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(express.static(path.join(__dirname, 'public')));

app.use(bodyParser.urlencoded({ extended: true }));
app.use(session({ secret: process.env.SESSION_SECRET }));

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

passport.serializeUser((user, done) => {
	done(null, user);
});

passport.deserializeUser((user, done) => {
	done(null, user);
});

// saml strategy for passport
var strategy = new saml(
	{
		entryPoint: process.env.SAML_ENTRYPOINT,
		issuer: process.env.SAML_ISSUER,
		protocol: process.env.SAML_PROTOCOL,
		logoutUrl: process.env.SAML_LOGOUTURL
	},
	(profile, done) => {
		userProfile = profile;
		done(null, userProfile);
	}
);

passport.use(strategy);

var redirectToLogin = (req, res, next) => {
	if (!req.isAuthenticated() || userProfile == null) {
		return res.redirect('/app/login');
	}
	next();
};

app.get('/app', redirectToLogin, (req, res) => {
	res.render('index', {
		title: 'Express Web Application',
		heading: 'Logged-In to Express Web Application'
	});
});

app.get(
	'/app/login',
	passport.authenticate('saml', {
		successRedirect: '/app',
		failureRedirect: '/app/login'
	})
);

app.get('/app/logout', (req, res) => {
	if (req.user == null) {
		return res.redirect('/app/home');
	}

	return strategy.logout(req, (err, uri) => {
		req.logout();

		userProfile = null;
		return res.redirect(uri);
	});
});

app.get('/app/failed', (req, res) => {
	res.status(401).send('Login failed');
});

app.post(
	'/saml/consume',
	passport.authenticate('saml', {
		failureRedirect: '/app/failed',
		failureFlash: true
	}),
	(req, res) => {

		// saml assertion extraction from saml response
		// var samlResponse = res.req.body.SAMLResponse;
		// var decoded = base64decode(samlResponse);
		// var assertion =
		// 	('<saml2:Assertion' + decoded.split('<saml2:Assertion')[1]).split(
		// 		'</saml2:Assertion>'
		// 	)[0] + '</saml2:Assertion>';
		// var urlEncoded = base64url(assertion);

		// success redirection to /app
		return res.redirect('/app');
	}
);

app.post('/app/home', (req, res) => {
	res.render('home', {
		title: 'Express Web Application',
		heading: 'Express Web Application'
	});
});

app.listen(process.env.PORT || 3000);