Sharing posts on Facebook and Twitter using Node REST API

I am making an application that requires users to log in, either via Twitter or Facebook and upon successful logging in, it redirects them to the /share url. I am not that much experienced with express, hence I believe that my approach here is wrong. I am using share-dialog npm package.

What I am trying to do is, once the user inputs the share links for twitter, I am sending them to the server via AJAX. Upon validation on the NODE's side, I am sending the object back to the client. Now I have no idea how to get to this object. Is my approach wrong?

Complete app.js:

var express = require('express')
    , passport = require('passport')
    , util = require('util')
    , FacebookStrategy = require('passport-facebook').Strategy
    , TwitterStrategy = require('passport-twitter').Strategy
    , session = require('express-session')
    , cookieParser = require('cookie-parser')
    , bodyParser = require('body-parser')
    , config = require('./configuration/config')
    , mysql = require('mysql')
    , Dialog = require('share-dialog')
    , cors = require ('cors')
    , app = express();

app.use(cors());
//If needed..
var connection = mysql.createConnection({
    host: config.host,
    user: config.username,
    password: config.password,
    database: config.database
});
//We are 'false'.
if (config.use_database === 'true') {
    connection.connect();
}
// Passport session setup.
passport.serializeUser(function (user, done) {
    done(null, user);
});
passport.deserializeUser(function (obj, done) {
    done(null, obj);
});
// Passport.js strategy with Facebook
passport.use(new FacebookStrategy({
        clientID: config.facebook_api_key,
        clientSecret: config.facebook_api_secret,
        callbackURL: config.facebook_callback_url,
        authURL: config.facebook_auth_url,
        logoutURL: config.logout_url
    },
    function (accessToken, refreshToken, profile, done) {
        process.nextTick(function () {
            //Check whether the user exists or not using profile.id
            return done(null, profile);
        });
    }
));
passport.use(new TwitterStrategy({
        consumerKey: config.twitter_api_key,
        consumerSecret: config.twitter_api_secret,
        callbackURL: config.twitter_callback_url,
        authURL: config.twitter_auth_url,
        logoutURL: config.logout_url
    },
    function (token, tokenSecret, profile, done) {
        process.nextTick(function () {
            //Check whether the user exists or not using profile.id
            return done(null, profile)
        });
    }
));

app.set('views', __dirname + '/views');
app.set('view engine', 'ejs');
app.use(cookieParser());
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: false}));
app.use(session({secret: 'keyboard cat', key: 'sid'}));
app.use(passport.initialize());
app.use(passport.session());
app.use(express.static(__dirname + '/public'));
//Router code
app.get('/', function (req, res) {
    res.render('index', {user: req.user});
});
app.get('/share', ensureAuthenticated, function(req, res) {
    res.render('share', {user: req.user});
});
app.post('/share', function(req, res) {
    var status = Object.keys(req.body).join('');
    var twitter = Dialog.twitter(status);
    var url = twitter.get();
    console.log(status);
    res.json({'url': url});
    res.end();
});
app.get('/share', ensureAuthenticated, function(req, res) {
    res.render('share', {user: req.user});
});
app.get('/account', ensureAuthenticated, function (req, res) {
    res.render('account', {user: req.user});
});
//Passport Router - Facebook OAuth
app.get('/auth/facebook', passport.authenticate('facebook'));
app.get('/auth/facebook/callback',
    passport.authenticate('facebook', {
        successRedirect: '/share',
        failureRedirect: '/'
    }),
    function (req, res) {
        res.redirect('/');
    });
//Passport Router - Twitter OAuth
app.get('/auth/twitter', passport.authenticate('twitter'));
app.get('/auth/twitter/callback',
    passport.authenticate('twitter', {
        successRedirect : '/share',
        failureRedirect: '/'
        }),
    function(req, res) {
        res.redirect('/');
    });

//Redirect and logout
app.get('/logout', function (req, res) {
    req.logout();
    res.redirect('/');
});

function ensureAuthenticated(req, res, next) {
    if (req.isAuthenticated()) {
        return next();
    }
    res.redirect('/')
}

// Redirect all 404
app.get('*', function (req, res) {
    res.render('404');
});

app.listen(3000);

Script.js on client's side:

function postLinks() {
    var shareVal = document.querySelector('#share-input').value;
    var xhr = new XMLHttpRequest();
    var url = "http://127.0.0.1:3000/share";

    xhr.open('POST', url, true);
    xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    xhr.onreadystatechange = function() {
        if(this.readyState === 4) {
            console.log("Passed: " + this.status);
        }
        else {
            console.log("Error: " + this.readyState);
        }
    };
    xhr.send(shareVal);
}

What should I do here guys? Please help.

EDIT: Please note that I do get the objects, for example:

url: "https://twitter.com/intent/tweet?url=http%3A%2F%2Fgoogle.com"

Thanks.

via tholo