Parse url and use pathname for prefix matching

Fixes #234

Author: brycekahle

lib/server.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const events = require('events');
+const url = require('url');
 const debug = require('debug')('sockjs:server');
 const listener = require('./listener');
 const webjs = require('./webjs');
@@ -41,7 +42,7 @@ class Server extends events.EventEmitter {
     if (this.options.prefix) {
       // remove trailing slash, but not leading
       this.options.prefix = this.options.prefix.replace(/\/$/, '');
-      this._prefixMatches = (url) => url.startsWith(this.options.prefix);
+      this._prefixMatches = (requrl) => url.parse(requrl).pathname.startsWith(this.options.prefix);
     }
 
     this.options.log('debug', `SockJS v${pkg.version} bound to ${JSON.stringify(this.options.prefix)}`);