union_data to json

@@ -233,8 +233,15 @@ exports.orderSub = (req, res, next) => {
 
             clientId = unionInfo && unionInfo.client_id;
         } else {
-            unionKey = '{"client_id":' + req.cookies.mkt_code +
-                (req.cookies.union_data ? ',"union_data":' + req.cookies.union_data : '') + '}';
+            let unionObj = {
+                client_id: req.cookies.mkt_code
+            };
+
+            if (req.cookies.union_data) {
+                unionObj.union_data = req.cookies.union_data;
+            }
+
+            unionKey = JSON.stringify(unionObj);
             clientId = req.cookies.mkt_code;
         }