Routing between Express and Angular in MEAN.JS - angularjs

Question

I ran into issues on calling a Express route from my Angular template route and Express -> Angular. This code shows my attempt into tackling this issue.
// Server.js file, the main Node.js code
var Outlook = require('Outlook');
// Bootstrap db connection
var db = mongoose.connect(config.db, function(err) {
etc..
});
// Init the express application
var app = require('./config/express')(db);
app.listen('8443'); // Main server.
// App.js - The Outlook module Express route example code
var app = require('express');
var app = express();
// Configure express
// Set up rendering of static files
app.use(express.static('static'));
// Need JSON body parser for most API responses
app.use(bodyParser.json());
// Set up cookies and sessions to save tokens
app.use(cookieParser());
// Home page
app.get('/', function(req, res) {
res.send(pages.loginPage(authHelper.getAuthUrl()));
});
app.get('/express', function(req, res) {
console.log(req.params.msg);
return 'Your EXPRESS DATA IS HERE!';
});
app.listen(3000); // Is this really necessary?
// outlook.cliet.routes.js
'use strict';
//Setting up route
angular.module('outlook').config(['$stateProvider', '$http',
function($http) {
$http.get('http://localhost:3000/express',{"msg":"hi"}).success(function(data){
console.log(data);
});
]);
Issue 1: I don't want to make express run two different servers in different ports in the same instance. That lead me to next issue.
I am using oauth-sign and simple-oauth2 when I bounce back from the outlook module to the main express server, I am logged off the main server.
I don't think it is required a separate express server. Is it possible to make app.js express routing work without listening to a second express server? Notice that express is initialized in a different way. Perhaps module.exports could help?
Thanks