meanTorrent/config/lib/express.js

'use strict';

/**
 * Module dependencies.
 */
var config = require('../config'),
	express = require('express'),
	morgan = require('morgan'),
	bodyParser = require('body-parser'),
	session = require('express-session'),
	MongoStore = require('connect-mongo')(session),
	multer = require('multer'),
	favicon = require('serve-favicon'),
	compress = require('compression'),
	methodOverride = require('method-override'),
	cookieParser = require('cookie-parser'),
	helmet = require('helmet'),
	passport = require('passport'),
	flash = require('connect-flash'),
	consolidate = require('consolidate'),
	path = require('path');

/**
 * Initialize local variables
 */
module.exports.initLocalVariables = function (app) {
	// Setting application local variables
	app.locals.title = config.app.title;
	app.locals.description = config.app.description;
	app.locals.keywords = config.app.keywords;
	app.locals.googleAnalyticsTrackingID = config.app.googleAnalyticsTrackingID;
	app.locals.facebookAppId = config.facebook.clientID;
	app.locals.jsFiles = config.files.client.js;
	app.locals.cssFiles = config.files.client.css;

	// Passing the request url to environment locals
	app.use(function (req, res, next) {
		res.locals.host = req.protocol + '://' + req.hostname;
		res.locals.url = req.protocol + '://' + req.headers.host + req.originalUrl;
		next();
	});
};

/**
 * Initialize application middleware
 */
module.exports.initMiddleware = function (app) {
	// Showing stack errors
	app.set('showStackError', true);

	// Enable jsonp
	app.enable('jsonp callback');

	// Should be placed before express.static
	app.use(compress({
		filter: function (req, res) {
			return (/json|text|javascript|css/).test(res.getHeader('Content-Type'));
		},
		level: 9
	}));

	// Initialize favicon middleware
	app.use(favicon('./modules/core/client/img/brand/favicon.ico'));

	// Environment dependent middleware
	if (process.env.NODE_ENV === 'development') {
		// Enable logger (morgan)
		app.use(morgan('dev'));

		// Disable views cache
		app.set('view cache', false);
	} else if (process.env.NODE_ENV === 'production') {
		app.locals.cache = 'memory';
	}

	// Request body parsing middleware should be above methodOverride
	app.use(bodyParser.urlencoded({
		extended: true
	}));
	app.use(bodyParser.json());
	app.use(methodOverride());

	// Add the cookie parser and flash middleware
	app.use(cookieParser());
	app.use(flash());

	// Add multipart handling middleware
	app.use(multer({
		dest: './uploads/',
		inMemory: true
	}));
};

/**
 * Configure view engine
 */
module.exports.initViewEngine = function (app) {
	// Set swig as the template engine
	app.engine('server.view.html', consolidate[config.templateEngine]);

	// Set views path and view engine
	app.set('view engine', 'server.view.html');
	app.set('views', './');
};

/**
 * Configure Express session
 */
module.exports.initSession = function (app, db) {
	// Express MongoDB session storage
	app.use(session({
		saveUninitialized: true,
		resave: true,
		secret: config.sessionSecret,
		store: new MongoStore({
			db: db.connection.db,
			collection: config.sessionCollection
		})
	}));
};

/**
 * Invoke modules server configuration
 */
module.exports.initModulesConfiguration = function (app, db) {
	config.files.server.configs.forEach(function (configPath) {
		require(path.resolve(configPath))(app, db);
	});
};

/**
 * Configure Helmet headers configuration
 */
module.exports.initHelmetHeaders = function (app) {
	// Use helmet to secure Express headers
	app.use(helmet.xframe());
	app.use(helmet.xssFilter());
	app.use(helmet.nosniff());
	app.use(helmet.ienoopen());
	app.disable('x-powered-by');
};

/**
 * Configure the modules static routes
 */
module.exports.initModulesClientRoutes = function (app) {
	// Setting the app router and static folder
	app.use('/', express.static(path.resolve('./public')));

	// Globbing static routing
	config.folders.client.forEach(function (staticPath) {
		app.use(staticPath.replace('/client', ''), express.static(path.resolve('./' + staticPath)));
	});
};

/**
 * Configure the modules ACL policies
 */
module.exports.initModulesServerPolicies = function (app) {
	// Globbing policy files
	config.files.server.policies.forEach(function (policyPath) {
		require(path.resolve(policyPath)).invokeRolesPolicies();
	});
};

/**
 * Configure the modules server routes
 */
module.exports.initModulesServerRoutes = function (app) {
	// Globbing routing files
	config.files.server.routes.forEach(function (routePath) {
		require(path.resolve(routePath))(app);
	});
};

/**
 * Configure error handling
 */
module.exports.initErrorRoutes = function (app) {
	// Assume 'not found' in the error msgs is a 404. this is somewhat silly, but valid, you can do whatever you like, set properties, use instanceof etc.
	app.use(function (err, req, res, next) {
		// If the error object doesn't exists
		if (!err) return next();

		// Log it
		console.error(err.stack);

		// Redirect to error page
		res.redirect('/server-error');
	});

	// Assume 404 since no middleware responded
	app.use(function (req, res) {
		// Redirect to not found page
		res.redirect('/not-found');
	});
};

/**
 * Configure Socket.io
 */
module.exports.configureSocketIO = function (app, db) {
	// Load the Socket.io configuration
	var server = require('./socket.io')(app, db);

	// Return server object
	return server;
};

/**
 * Initialize the Express application
 */
module.exports.init = function (db) {
	// Initialize express app
	var app = express();

	// Initialize local variables
	this.initLocalVariables(app);

	// Initialize Express middleware
	this.initMiddleware(app);

	// Initialize Express view engine
	this.initViewEngine(app);

	// Initialize Express session
	this.initSession(app, db);

	// Initialize Modules configuration
	this.initModulesConfiguration(app);

	// Initialize Helmet security headers
	this.initHelmetHeaders(app);

	// Initialize modules static client routes
	this.initModulesClientRoutes(app);

	// Initialize modules server authorization policies
	this.initModulesServerPolicies(app);

	// Initialize modules server routes
	this.initModulesServerRoutes(app);

	// Initialize error routes
	this.initErrorRoutes(app);

	// Configure Socket.io
	app = this.configureSocketIO(app, db);

	return app;
};