New config option to use an external websocket server

config.js.dist

@@ -50,6 +50,12 @@ module.exports = {
      */
     //websocketPort: 3000,
 
+    /*  if you want to run a different version of cryptpad but using the same websocket
+     *  server, you should use the other server port as websocketPort and disable 
+     *  the websockets on that server
+     */
+    //useExternalWebsocket: false,
+
     /*  If Cryptpad is proxied without using https, the server needs to know.
      *  Specify 'useSecureWebsockets: true' so that it can send
      *  Content Security Policy Headers that prevent http and https from mixing

server.js

@@ -82,7 +82,7 @@ app.get('/api/config', function(req, res){
     var host = req.headers.host.replace(/\:[0-9]+/, '');
     res.setHeader('Content-Type', 'text/javascript');
     res.send('define(' + JSON.stringify({
-        websocketPath: config.websocketPath,
+        websocketPath: config.useExternalWebsocket ? undefined : config.websocketPath,
         websocketURL:'ws' + ((useSecureWebsockets) ? 's' : '') + '://' + host + ':' +
             websocketPort + '/cryptpad_websocket',
     }) + ');');
@@ -95,6 +95,8 @@ httpServer.listen(config.httpPort,config.httpAddress,function(){
 });
 
 var wsConfig = { server: httpServer };
+
+if(!config.useExternalWebsocket) {
     if (websocketPort !== config.httpPort) {
         console.log("setting up a new websocket server");
         wsConfig = { port: websocketPort};
@@ -103,3 +105,4 @@ var wsSrv = new WebSocketServer(wsConfig);
     Storage.create(config, function (store) {
         NetfluxSrv.run(store, wsSrv, config);
     });
+}