Browser Output "Cannot read property '0' of undefined"

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var mongoose = require('mongoose');
var passport = require('passport');
var GitHubStrategy = require('passport-github').Strategy;
var session = require('express-session');
var MongoStore = require('connect-mongo')(session);
var User = require("./models/user");

//Configure Github Strategy
passport.use(new GitHubStrategy({
  clientID : process.env.GITHUB_CLIENT_ID,
  clientSecret : process.env.GITHUB_CLIENT_SECRET,
  callbackURL : "http://localhost:3000/auth/github/return"
}, function(accessToken, refreshToken, profile, done){
  if(profile.emails[0]){
  User.findOneAndUpdate({
    email : profile.emails[0].value
  }, {
    name : profile.displayName || profile.username,
    email : profile.emails[0].value,
    photo : profile.photos[0].value
  }, {
    upsert : true
  },
  done);
} else {
  var noEmailError = new Error("Your email privacy settings prevent you from signing into bookworm!");
  done(noEmailError, null);
}
}));

passport.serializeUser(function(user, done){
  done(null, user._id);
});
passport.deserializeUser(function(userId, done){
  User.findById(userId, done);
});

var routes = require('./routes/index');
var auth = require('./routes/auth');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

// mongodb connection
mongoose.connect("mongodb://localhost:27017/bookworm-oauth");
var db = mongoose.connection;

//Session config for Passport and MongoDB
var sessionOptions = {
  secret : 'this is a super secret dadada',
  resave : true,
  saveUninitialized : true,
  store : new MongoStore({
    mongooseConnection : db
  })
};


app.use(session(sessionOptions));

//Initialize Passport
app.use(passport.initialize());
//Restore Session
app.use(passport.session());

// mongo error
db.on('error', console.error.bind(console, 'connection error:'));

app.use('/', routes);
app.use('/auth', auth);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
  app.use(function(err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
      message: err.message,
      error: err
    });
  });
}

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});


module.exports = app;

var express = require('express');
var router = express.Router();
var passport = require('passport');

//GET /auth/login/github
router.get('/login/github', passport.authenticate('github'));

//GET /auth/github/return
router.get('/github/return', passport.authenticate('github', {failureRedirect: '/'}),
function(req, res){
  //Success Auth, redirect to profile page
  res.redirect('profile');
});

//GET /auth/logout
router.get('/logout', function(req, res){
  req.logout();
  req.redirect('/');
});

module.exports = router;