organize middlewares

removed app.locals.middleware
middlewares can be required anywhere, ie in controllers

src/middleware/headers.js

@@ -0,0 +1,51 @@
+'use strict';
+
+
+var meta = require('../meta');
+var _ = require('underscore');
+
+
+module.exports = function(middleware) {
+
+	middleware.addHeaders = function (req, res, next) {
+		var defaults = {
+			'X-Powered-By': 'NodeBB',
+			'X-Frame-Options': 'SAMEORIGIN',
+			'Access-Control-Allow-Origin': 'null'	// yes, string null.
+		};
+		var headers = {
+			'X-Powered-By': meta.config['powered-by'],
+			'X-Frame-Options': meta.config['allow-from-uri'] ? 'ALLOW-FROM ' + meta.config['allow-from-uri'] : undefined,
+			'Access-Control-Allow-Origin': meta.config['access-control-allow-origin'],
+			'Access-Control-Allow-Methods': meta.config['access-control-allow-methods'],
+			'Access-Control-Allow-Headers': meta.config['access-control-allow-headers']
+		};
+
+		_.defaults(headers, defaults);
+		headers = _.pick(headers, Boolean);		// Remove falsy headers
+
+		for(var key in headers) {
+			if (headers.hasOwnProperty(key)) {
+				res.setHeader(key, headers[key]);
+			}
+		}
+
+		next();
+	};
+
+	middleware.addExpiresHeaders = function(req, res, next) {
+		if (req.app.enabled('cache')) {
+			res.setHeader("Cache-Control", "public, max-age=5184000");
+			res.setHeader("Expires", new Date(Date.now() + 5184000000).toUTCString());
+		} else {
+			res.setHeader("Cache-Control", "public, max-age=0");
+			res.setHeader("Expires", new Date().toUTCString());
+		}
+
+		next();
+	};
+
+};
+
+
+