Cannot read property 'username' of undefined while trying to access the req.user property in node js

Question

I am using MEAN Stack. I want to access the req.user property. But I am getting an error saying Cannot read property 'username' of undefined when I try to display the username of current user. I reffered to some sites. https://www.airpair.com/express/posts/expressjs-and-passportjs-sessions-deep-dive

Similar question Node + Express + Passport: req.user Undefined

It has been mentioned the order of the middleware functions matters. I corrected those. Still I am getting the same error. What is my mistake?

app.js

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 mongo = require('mongodb');
var mongoose = require("mongoose");
var expressValidator = require('express-validator');
var flash = require('connect-flash');
var session = require('express-session');
var passport = require('passport');
var LocalStrategy = require('passport-local').Strategy;
var ConnectRoles = require('connect-roles');
var User = require('./models/user');


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

db.on("error", console.error.bind(console, "Connection error:"));
db.once("open", function(callback){
    console.log("Connection Succeeded."); 
});

var routes = require('./routes/Login');
var admin = require('./routes/AdminDatabase');
var survey = require('./routes/CreateSurvey');
var submit = require('./routes/SubmitSurvey');

var app = express();

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

app.use(logger('dev'));
app.use(express.static(path.join(__dirname, 'public')));
app.use(cookieParser());
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));

app.use(session({
    secret: 'secret',
    saveUninitialized: true,
    resave: true
}));

app.use(passport.initialize());
app.use(passport.session());
app.use(flash());
app.use(function (req, res, next) {
  res.locals.success_msg = req.flash('success_msg');
  res.locals.error_msg = req.flash('error_msg');
  res.locals.error = req.flash('error');
  res.locals.user = req.user || null;

  next();
});

app.use('/', routes);
app.use('/AdminDatabase', admin);
app.use('/CreateSurvey', survey);
app.use('/SubmitSurvey', submit);

app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});


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
  });
}


app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});

app.get('/AdminDatabase', function(req, res){
    user.find({}, function(err, profile){
        res.render('AdminDatabase', {profile:profile});  
    });
});
module.exports = app;

Login.js (where I have the passport and routes)

var express = require('express');
var router = express.Router();
var passport = require('passport');
var LocalStrategy = require('passport-local').Strategy;
var User = require('../models/user');
var ConnectRoles = require('connect-roles');

router.get('/', function(req, res, next) {
  res.render('Login', { title: 'Login' });
});

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 LocalStrategy(
     function(username, password, done) {
        User.findOne({ username: username }, function(err, user) {
            if (err) { return done(err); }

            if (!user) {
                return done(null, false,
                 { message: "No user has that username!" });
            }

            user.checkPassword(password, function(err, isMatch) {

            if (err) { return done(err); }
                if (isMatch) {
                    return done(null, user);
                } else {
                    return done(null, false,{ message: "Invalid password." });
            }
        });
    });
}));

router.use(function(req, res, next) {
    res.locals.currentUser = req.user;
    res.locals.errors = req.flash("error");
    res.locals.infos = req.flash("info");

    next();
});

router.post("/", passport.authenticate("/", {
    successRedirect: "/SubmitSurvey",
    failureRedirect: "/",
    session: false,
    failureFlash: true
}));

router.get("/AdminDatabase", function(req, res) {
   res.render('AdminDatabase', { title: 'AdminDatabase' });
 });

router.get('/CreateSurvey', function(req, res, next) {
  res.render('CreateSurvey', { title: 'CreateSurvey' });
});

router.get('/SubmitSurvey', function(req, res, next) {
  res.render('SubmitSurvey', { title: 'SubmitSurvey' });
});

router.get('/profile', function(req, res){
  var user= res.user;
  res.render('profile', { title: 'profile', user: user });
});

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

module.exports = router;

Answer 1

I can't see where you initialized your passport.js with express.js

You should add it as middleware

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

That should help you. If it not helped you please take a look for this example. https://blog.risingstack.com/node-hero-node-js-authentication-passport-js/

Answer 2

I dont know how your client sends its data, whether by body or QS...but to access that information from the server side, you would need to do something like the below:

req.params.user 

or

req.body.user

using req.user will always be undef because there is no such property to the request object.