MC-18995: Page Builder & PWA Studio Compatibility

- Fix Product Widget list rendering through GraphQL

Author: davemacaulay

app/code/Magento/CmsGraphQl/Plugin/DesignLoader.php

@@ -0,0 +1,68 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CmsGraphQl\Plugin;
+
+use Magento\Catalog\Model\Product;
+use Magento\Framework\Message\MessageInterface;
+
+/**
+ * Load necessary design files for GraphQL
+ */
+class DesignLoader
+{
+    /**
+     * @var \Magento\Framework\View\DesignLoader
+     */
+    protected $designLoader;
+
+    /**
+     * @var \Magento\Framework\Message\ManagerInterface
+     */
+    protected $messageManager;
+
+    /**
+     * @param \Magento\Framework\View\DesignLoader $designLoader
+     * @param \Magento\Framework\Message\ManagerInterface $messageManager
+     */
+    public function __construct(
+        \Magento\Framework\View\DesignLoader $designLoader,
+        \Magento\Framework\Message\ManagerInterface $messageManager
+    ) {
+        $this->designLoader = $designLoader;
+        $this->messageManager = $messageManager;
+    }
+
+    /**
+     * Before create load the design files
+     *
+     * @param \Magento\Catalog\Block\Product\ImageFactory $subject
+     * @param Product $product
+     * @param string $imageId
+     * @param array|null $attributes
+     *
+     * @SuppressWarnings(PHPMD.UnusedFormalParameter)
+     */
+    public function beforeCreate(
+        \Magento\Catalog\Block\Product\ImageFactory $subject,
+        Product $product,
+        string $imageId,
+        array $attributes = null
+    ) {
+        try {
+            $this->designLoader->load();
+        } catch (\Magento\Framework\Exception\LocalizedException $e) {
+            if ($e->getPrevious() instanceof \Magento\Framework\Config\Dom\ValidationException) {
+                /** @var MessageInterface $message */
+                $message = $this->messageManager
+                    ->createMessage(MessageInterface::TYPE_ERROR)
+                    ->setText($e->getMessage());
+                $this->messageManager->addUniqueMessages([$message]);
+            }
+        }
+    }
+}

app/code/Magento/CmsGraphQl/etc/graphql/di.xml

@@ -18,4 +18,7 @@
             </argument>
         </arguments>
     </type>
+    <type name="Magento\Catalog\Block\Product\ImageFactory">
+        <plugin name="designLoader" type="Magento\CmsGraphQl\Plugin\DesignLoader" />
+    </type>
 </config>