diff --git a/webapp/controller/ShopController.class.php b/webapp/controller/ShopController.class.php
index 7c343de0..252374db 100644
--- a/webapp/controller/ShopController.class.php
+++ b/webapp/controller/ShopController.class.php
@@ -1089,6 +1089,13 @@ class ShopController extends BaseAuthedController
         $item_id = $goods['goods_id'];
         $item_count = $goods['goods_num'] * $count;
 
+        error_log("buyGoodsDS start " + json_encode(array(
+            'idx' => $idx,
+            'grid' => $grid,
+            'count' => $count,
+        )
+        ));
+
         $response = services\BlockChainService::gameItemMallBuy(
             Transaction::BUY_GOODS_ACTION_TYPE,
             $price,