Node, module usage structure

I’ve been trying to understand how to set up Stripe for my app but am having problems with the implementation of the module. Normally when using a module i would require it in the top of the file to be able to use it but I’m not sure how to do this here in the paymentController file or if i even need to. I imported the Stripe npm, so does that i mean that i can access it globally? Well as you see i’m quite new to this and would like to understand how to structure this so that the payments work.

app.js file:

angular.module('userApp', ['appRoutes', 'userControllers', 'userServices', 'ngAnimate', 'mainController', 'authServices', 'managementController', 'paymentController'])

.config(function($httpProvider) {
    $httpProvider.interceptors.push('AuthInterceptors');
});

paymentController file:

angular.module('paymentController', [])

.controller('paymentCtrl', function($scope) {

  var app = this; 


});

Server.js file:

var express = require('express'); // ExperssJS Framework
var app = express(); // Invoke express to variable for use in application
var port = process.env.PORT || 8080; // Set default port or assign a port in enviornment
var morgan = require('morgan'); // Import Morgan Package
var mongoose = require('mongoose'); // HTTP request logger middleware for Node.js
var bodyParser = require('body-parser'); // Node.js body parsing middleware. Parses incoming request bodies in a middleware before your handlers, available under req.body.
var router = express.Router(); // Invoke the Express Router
var appRoutes = require('./app/routes/api')(router); // Import the application end points/API
var path = require('path'); // Import path module
var passport = require('passport'); // Express-compatible authentication middleware for Node.js.
var social = require('./app/passport/passport')(app, passport); // Import passport.js End Points/API

app.use(morgan('dev')); // Morgan Middleware
app.use(bodyParser.json()); // Body-parser middleware
app.use(bodyParser.urlencoded({ extended: true })); // For parsing application/x-www-form-urlencoded
app.use(express.static(__dirname + '/public')); // Allow front end to access public folder
app.use('/api', appRoutes); // Assign name to end points (e.g., '/api/management/', '/api/users' ,etc. )


mongoose.connect('mongodb://localhost:27017/tutorial', function(err) {
  if (err) {
    console.log('Not connected to the database: ' + err);
  } else {
    console.log('Successfully connected to MongoDB');
  }
});

// Set Application Static Layout
app.get('*', function(req, res) {
    res.sendFile(path.join(__dirname + '/public/app/views/index.html')); // Set index.html as layout
});

// Start Server
app.listen(port, function() {
    console.log('Running the server on port ' + port); // Listen on configured port
});

Source: AngularJS