Add server-side latency (vfs -> docker host)

node_modules/vfs-socket/worker.js

@@ -322,10 +322,30 @@ function Worker(vfs) {
         delete watchers[id];
         watcher.close();
     }
+    
+    /**
+     * Add additional timing info to any "ping" call.
+     */
+    function wrapPingCall(name, fnName, args) {
+        if (name === "ping" && fnName === "ping" && args.length === 2) {
+            var start = Date.now();
+            var cb = args[1];
+            
+            args[1] = function(err, payload) {
+                if (err) return cb(err);
+                cb(null, {
+                    payload: payload,
+                    serverTime: Date.now() - start
+                });
+            };
+        }
+    }
 
     function call(name, fnName, args) {
         var api = apis[name];
         if (!api) return;
+        
+        wrapPingCall(name, fnName, args);
 
         // If the last arg is a function, assume it's a callback and process it.
         if (typeof args[args.length - 1] == "function") {

plugins/c9.vfs.client/vfs.ping.js

@@ -60,11 +60,14 @@ define(function(require, exports, module) {
             if (!api) return callback(new Error("Client is offline"));
 
             var start = Date.now();
-            api.ping("ping", function(err) {
+            api.ping("ping", function(err, response) {
                 var took = Date.now() - start;
                 if (err) return callback(err);
 
-                callback(null, took);
+                callback(null, {
+                    serverTime: response.serverTime,
+                    total: took
+                });
             });
         }