Add child identities of bundle and configurable products on frontend instead of parent identities

Author: jasperzeinstra

app/code/Magento/Bundle/Model/Plugin/Frontend/Product.php

@@ -0,0 +1,45 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Bundle\Model\Plugin\Frontend;
+
+use Magento\Bundle\Model\Product\Type;
+use Magento\Catalog\Model\Product as CatalogProduct;
+
+class Product
+{
+    /**
+     * @var Type
+     */
+    private $type;
+
+    /**
+     * @param Type $type
+     */
+    public function __construct(Type $type)
+    {
+        $this->type = $type;
+    }
+
+    /**
+     * Add child identities to product identities
+     *
+     * @param CatalogProduct $product
+     * @param array $identities
+     * @return string[]
+     */
+    public function afterGetIdentities(
+        CatalogProduct $product,
+        array $identities
+    ) {
+        foreach ($this->type->getChildrenIds($product->getEntityId()) as $optionId => $childIds) {
+            foreach ($childIds as $childId) {
+                $identities[] = CatalogProduct::CACHE_TAG . '_' . $childId;
+            }
+        }
+
+        return array_unique($identities);
+    }
+}

app/code/Magento/Bundle/etc/frontend/di.xml

@@ -13,4 +13,7 @@
             </argument>
         </arguments>
     </type>
+    <type name="Magento\Catalog\Model\Product">
+        <plugin name="bundle" type="Magento\Bundle\Model\Plugin\Frontend\Product" sortOrder="100" />
+    </type>
 </config>

app/code/Magento/ConfigurableProduct/Model/Plugin/Frontend/ProductIdentitiesExtender.php

@@ -0,0 +1,57 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\ConfigurableProduct\Model\Plugin\Frontend;
+
+use Magento\ConfigurableProduct\Model\Product\Type\Configurable;
+use Magento\Catalog\Api\ProductRepositoryInterface;
+use Magento\Catalog\Model\Product;
+
+/**
+ *  Extender of product identities for child of configurable products
+ */
+class ProductIdentitiesExtender
+{
+    /**
+     * @var Configurable
+     */
+    private $configurableType;
+
+    /**
+     * @var ProductRepositoryInterface
+     */
+    private $productRepository;
+
+    /**
+     * @param Configurable $configurableType
+     * @param ProductRepositoryInterface $productRepository
+     */
+    public function __construct(Configurable $configurableType, ProductRepositoryInterface $productRepository)
+    {
+        $this->configurableType = $configurableType;
+        $this->productRepository = $productRepository;
+    }
+
+    /**
+     * Add child identities to product identities
+     *
+     * @param Product $subject
+     * @param array $identities
+     * @return array
+     * @SuppressWarnings(PHPMD.UnusedFormalParameter)
+     */
+    public function afterGetIdentities(Product $subject, array $identities): array
+    {
+        foreach ($this->configurableType->getChildrenIds($subject->getId()) as $key => $childIds) {
+            foreach ($childIds as $childId) {
+                $identities[] = Product::CACHE_TAG . '_' . $childId;
+            }
+        }
+
+        return array_unique($identities);
+    }
+}

app/code/Magento/ConfigurableProduct/etc/frontend/di.xml

@@ -10,4 +10,7 @@
     <type name="Magento\ConfigurableProduct\Model\ResourceModel\Attribute\OptionSelectBuilderInterface">
         <plugin name="Magento_ConfigurableProduct_Plugin_Model_ResourceModel_Attribute_InStockOptionSelectBuilder" type="Magento\ConfigurableProduct\Plugin\Model\ResourceModel\Attribute\InStockOptionSelectBuilder"/>
     </type>
+    <type name="Magento\Catalog\Model\Product">
+        <plugin name="product_identities_extender" type="Magento\ConfigurableProduct\Model\Plugin\Frontend\ProductIdentitiesExtender" />
+    </type>
 </config>