fix headers for new installs

encodeURI(undefined) === "undefined"

src/middleware/headers.js

@@ -1,31 +1,20 @@
 'use strict';
 
-
-var _ = require('underscore');
-
 var meta = require('../meta');
 
 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': encodeURI(meta.config['powered-by']),
+			'X-Powered-By': encodeURI(meta.config['powered-by'] || 'NodeBB'),
-			'X-Frame-Options': meta.config['allow-from-uri'] ? 'ALLOW-FROM ' + encodeURI(meta.config['allow-from-uri']) : undefined,
+			'X-Frame-Options': meta.config['allow-from-uri'] ? 'ALLOW-FROM ' + encodeURI(meta.config['allow-from-uri']) : 'SAMEORIGIN',
-			'Access-Control-Allow-Origin': encodeURI(meta.config['access-control-allow-origin']),
+			'Access-Control-Allow-Origin': encodeURI(meta.config['access-control-allow-origin'] || 'null'),
-			'Access-Control-Allow-Methods': encodeURI(meta.config['access-control-allow-methods']),
+			'Access-Control-Allow-Methods': encodeURI(meta.config['access-control-allow-methods'] || ''),
-			'Access-Control-Allow-Headers': encodeURI(meta.config['access-control-allow-headers'])
+			'Access-Control-Allow-Headers': encodeURI(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)) {
+			if (headers.hasOwnProperty(key) && headers[key]) {
 				res.setHeader(key, headers[key]);
 			}
 		}