Fix json endpoint

statsd/endpoint/mongodb/index.js

@@ -25,9 +25,11 @@ app.use(morgan('combined'));
 app.use(bodyParser.json());
 
 function setCORSHeaders(res) {
-  res.setHeader("Access-Control-Allow-Origin", "*");
-  res.setHeader("Access-Control-Allow-Methods", "POST");
-  res.setHeader("Access-Control-Allow-Headers", "accept, content-type");  
+    if (res) {        
+        res.setHeader("Access-Control-Allow-Origin", "*");
+        res.setHeader("Access-Control-Allow-Methods", "POST");
+        res.setHeader("Access-Control-Allow-Headers", "accept, content-type");  
+    }
 }
 
 app.all('/', function(req, res) {
@@ -127,12 +129,16 @@ function checkResult()
         return false;
     }
     
-    setCORSHeaders(global_res);
-    global_res.json(global_result);
-    global_res.end();
-    
     clearInterval(checkInterval);
     
+    if (global_res) {
+        setCORSHeaders(global_res);
+        global_res.json(global_result);
+        global_res.end();
+    }
+    
+    global_res = null;
+    
     return true;
 }