product url 判空

app/code/Magento/Sales/Model/Order/Item.php

@@ -2422,6 +2422,9 @@ class Item extends AbstractModel implements OrderItemInterface
     public function getImage() {
         $product = $this->productRepository->get($this->getSku());
         if ($product) {
+            if (!$product->getData("thumbnail")) {
+                return "null";
+            }
             $objectManager = \Magento\Framework\App\ObjectManager::getInstance();
             $storeManager = $objectManager->get('\Magento\Store\Model\StoreManagerInterface');
             $hostname = $storeManager->getStore()->getBaseUrl();