[fix] closes #553

lib/http-proxy/index.js

@@ -26,9 +26,15 @@ httpProxy.Server = ProxyServer;
  */
 
 function createRightProxy(type) {
+  var webPasses = Object.keys(web).map(function(pass) {
+    return web[pass];
+  });
+  var wsPasses = Object.keys(ws).map(function(pass) {
+    return ws[pass];
+  });
   return function(options) {
     return function(req, res /*, [head], [opts] */) {
-      var passes = (type === 'ws') ? this.wsPasses : this.webPasses,
+      var passes = (type === 'ws') ? (this.wsPasses || wsPasses) : (this.webPasses || webPasses),
           args = [].slice.call(arguments),
           cntr = args.length - 1,
           head, cbl;
@@ -62,7 +68,8 @@ function createRightProxy(type) {
         if (typeof options[e] === 'string')
           options[e] = parse_url(options[e]);
       });
-
+
+      if(typeof this.emit == 'undefined' && !cbl) { throw new Error("You need to pass a callback to handle errors") }
 
       for(var i=0; i < passes.length; i++) {
         /**