Merge branch 'MAGETWO-93038' into mpi-PR-2008

Author: Mariana Lashch

app/code/Magento/Catalog/Observer/CategoryProductIndexer.php

@@ -0,0 +1,43 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Catalog\Observer;
+
+use Magento\Catalog\Model\Indexer\Category\Product\Processor;
+use Magento\Framework\Event\Observer;
+use Magento\Framework\Event\ObserverInterface;
+
+/**
+ * Checks if a category has changed products and depends on indexer configuration
+ * marks `Category Products` indexer as invalid or reindexes affected products.
+ */
+class CategoryProductIndexer implements ObserverInterface
+{
+    /**
+     * @var Processor
+     */
+    private $processor;
+
+    /**
+     * @param Processor $processor
+     */
+    public function __construct(Processor $processor)
+    {
+        $this->processor = $processor;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function execute(Observer $observer)
+    {
+        $productIds = $observer->getEvent()->getProductIds();
+        if (!empty($productIds) && $this->processor->isIndexerScheduled()) {
+            $this->processor->markIndexerAsInvalid();
+        }
+    }
+}

app/code/Magento/Catalog/etc/adminhtml/events.xml

@@ -9,4 +9,7 @@
     <event name="cms_wysiwyg_images_static_urls_allowed">
         <observer name="catalog_wysiwyg" instance="Magento\Catalog\Observer\CatalogCheckIsUsingStaticUrlsAllowedObserver" />
     </event>
+    <event name="catalog_category_change_products">
+        <observer name="category_product_indexer" instance="Magento\Catalog\Observer\CategoryProductIndexer"/>
+    </event>
 </config>