From e5ae941438ac29a1cecbf626e075944a3cf43980 Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Thu, 21 May 2020 14:57:33 +0300
Subject: [PATCH 1/7] #catalog-storefront/issue-12 Add new GraphQL endpoint for
 single product retrieval

---
 .../DataProvider/ProductDataProvider.php      | 58 +++++++++++++++
 .../ProductDataProviderInterface.php          | 25 +++++++
 .../Resolver/Product/ProductIdIdentity.php    | 34 +++++++++
 .../Model/Resolver/ProductId.php              | 72 +++++++++++++++++++
 app/code/Magento/CatalogGraphQl/etc/di.xml    |  1 +
 .../CatalogGraphQl/etc/schema.graphqls        |  4 ++
 6 files changed, 194 insertions(+)
 create mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
 create mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
 create mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
 create mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php

diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
new file mode 100644
index 0000000000000..74db074e2b581
--- /dev/null
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
@@ -0,0 +1,58 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider;
+
+use Magento\Catalog\Api\Data\ProductInterface;
+use Magento\Catalog\Model\ProductFactory;
+use Magento\Catalog\Model\ResourceModel\Product as ProductResourceModel;
+
+/**
+ * Product data provider, used for GraphQL resolver processing.
+ */
+class ProductDataProvider implements ProductDataProviderInterface
+{
+    /**
+     * @var ProductResourceModel
+     */
+    private $productResourceModel;
+
+    /**
+     * @var ProductFactory
+     */
+    private $productFactory;
+
+    /**
+     * ProductDataProvider constructor.
+     *
+     * @param ProductResourceModel $productResourceModel
+     * @param ProductFactory $productFactory
+     */
+    public function __construct(
+        ProductResourceModel $productResourceModel,
+        ProductFactory $productFactory
+    ) {
+        $this->productResourceModel = $productResourceModel;
+        $this->productFactory = $productFactory;
+    }
+
+    /**
+     * Get product data by ID with full data set
+     *
+     * @param int $productId
+     * @param array $attributeCodes
+     * @return ProductInterface|Product
+     */
+    public function getProductById(int $productId, array $attributeCodes)
+    {
+        /** @var \Magento\Catalog\Model\Product $product */
+        $product = $this->productFactory->create();
+        $this->productResourceModel->load($product, $productId, $attributeCodes);
+
+        return $product;
+    }
+}
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
new file mode 100644
index 0000000000000..acd18c7f92e5f
--- /dev/null
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
@@ -0,0 +1,25 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider;
+
+use Magento\Catalog\Api\Data\ProductInterface;
+
+/**
+ * Provides product data by product ID.
+ */
+interface ProductDataProviderInterface
+{
+    /**
+     * Retrieve product by product ID.
+     *
+     * @param int $productId
+     * @param array $attributeCodes
+     * @return ProductInterface
+     */
+    public function getProductById(int $productId, array $attributeCodes);
+}
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
new file mode 100644
index 0000000000000..dbe24a375eade
--- /dev/null
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CatalogGraphQl\Model\Resolver\Product;
+
+use Magento\Catalog\Model\Product;
+use Magento\Framework\GraphQl\Query\Resolver\IdentityInterface;
+
+/**
+ * Identity for resolved product by ID
+ */
+class ProductIdIdentity implements IdentityInterface
+{
+    /**
+     * @var string
+     */
+    private $cacheTag = Product::CACHE_TAG;
+
+    /**
+     * Get product id for cache tag
+     *
+     * @param array $resolvedData
+     * @return array
+     */
+    public function getIdentities(array $resolvedData): array
+    {
+        return empty($resolvedData['id']) ?
+            [] : [$this->cacheTag, $resolvedData['id']];
+    }
+}
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
new file mode 100644
index 0000000000000..8174c751982e1
--- /dev/null
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
@@ -0,0 +1,72 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CatalogGraphQl\Model\Resolver;
+
+use Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider\ProductDataProviderInterface;
+use Magento\CatalogGraphQl\Model\Resolver\Product\ProductFieldsSelector;
+use Magento\Framework\GraphQl\Config\Element\Field;
+use Magento\Framework\GraphQl\Exception\GraphQlInputException;
+use Magento\Framework\GraphQl\Query\ResolverInterface;
+use Magento\Framework\GraphQl\Schema\Type\ResolveInfo;
+
+/**
+ * Product by ID resolver, used for GraphQL request processing.
+ */
+class ProductId implements ResolverInterface
+{
+    /**
+     * @var ProductDataProviderInterface
+     */
+    private $productDataProvider;
+
+    /**
+     * @var ProductFieldsSelector
+     */
+    private $productFieldsSelector;
+
+    /**
+     * ProductId constructor.
+     *
+     * @param ProductDataProviderInterface $productDataProvider
+     * @param ProductFieldsSelector $productFieldsSelector
+     */
+    public function __construct(
+        ProductDataProviderInterface $productDataProvider,
+        ProductFieldsSelector $productFieldsSelector
+    ) {
+        $this->productDataProvider = $productDataProvider;
+        $this->productFieldsSelector = $productFieldsSelector;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function resolve(
+        Field $field,
+        $context,
+        ResolveInfo $info,
+        array $value = null,
+        array $args = null
+    ) {
+        $productId = (int) ($args['id'] ?? 0);
+        $fields = $this->productFieldsSelector->getProductFieldsFromInfo($info);
+
+        if (!$productId) {
+            throw new GraphQlInputException(
+                __("'id' input argument is required.")
+            );
+        }
+
+        /** @var \Magento\Catalog\Model\Product $product */
+        $product = $this->productDataProvider->getProductById($productId, $fields);
+        $data = $product->getData();
+        $data['model'] = $product;
+
+        return $data;
+    }
+}
diff --git a/app/code/Magento/CatalogGraphQl/etc/di.xml b/app/code/Magento/CatalogGraphQl/etc/di.xml
index 5fec7bfd4fda7..8abd7e9ed14fe 100644
--- a/app/code/Magento/CatalogGraphQl/etc/di.xml
+++ b/app/code/Magento/CatalogGraphQl/etc/di.xml
@@ -74,4 +74,5 @@
     <preference type="\Magento\CatalogGraphQl\Model\Resolver\Product\Price\Provider" for="\Magento\CatalogGraphQl\Model\Resolver\Product\Price\ProviderInterface"/>
 
     <preference type="Magento\CatalogGraphQl\Model\Resolver\Products\Query\Search" for="Magento\CatalogGraphQl\Model\Resolver\Products\Query\ProductQueryInterface"/>
+    <preference type="Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider\ProductDataProvider" for="Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider\ProductDataProviderInterface"/>
 </config>
diff --git a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
index f77b301d61e28..85aeb9e6a8f10 100644
--- a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
+++ b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
@@ -10,6 +10,10 @@ type Query {
         sort: ProductAttributeSortInput @doc(description: "Specifies which attributes to sort on, and whether to return the results in ascending or descending order.")
     ): Products
     @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\Products") @doc(description: "The products query searches for products that match the criteria specified in the search and filter attributes.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\Identity")
+    product (
+        id: Int @doc(description: "Id of the product.")
+    ): ProductInterface
+    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductId") @doc(description: "The product query searches for product that match the criteria specified in the search and filter attributes.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductIdIdentity")
     category (
      id: Int @doc(description: "Id of the category.")
     ): CategoryTree

From 5d21f2367d6a0f1573dc3c00724633ea0d466efc Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Fri, 22 May 2020 09:48:55 +0300
Subject: [PATCH 2/7] Add strict type

---
 .../Resolver/Product/DataProvider/ProductDataProvider.php    | 5 +++--
 .../Product/DataProvider/ProductDataProviderInterface.php    | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
index 74db074e2b581..0166318a0dcb6 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
@@ -8,6 +8,7 @@
 namespace Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider;
 
 use Magento\Catalog\Api\Data\ProductInterface;
+use Magento\Catalog\Model\Product;
 use Magento\Catalog\Model\ProductFactory;
 use Magento\Catalog\Model\ResourceModel\Product as ProductResourceModel;
 
@@ -47,9 +48,9 @@ public function __construct(
      * @param array $attributeCodes
      * @return ProductInterface|Product
      */
-    public function getProductById(int $productId, array $attributeCodes)
+    public function getProductById(int $productId, array $attributeCodes): ProductInterface
     {
-        /** @var \Magento\Catalog\Model\Product $product */
+        /** @var Product $product */
         $product = $this->productFactory->create();
         $this->productResourceModel->load($product, $productId, $attributeCodes);
 
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
index acd18c7f92e5f..9a00e0e1e0d21 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
@@ -21,5 +21,5 @@ interface ProductDataProviderInterface
      * @param array $attributeCodes
      * @return ProductInterface
      */
-    public function getProductById(int $productId, array $attributeCodes);
+    public function getProductById(int $productId, array $attributeCodes): ProductInterface;
 }

From 4e17fd7dc31ddaaf158d9c9d4351e9aaddba5025 Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Fri, 22 May 2020 09:49:41 +0300
Subject: [PATCH 3/7] Adjust description

---
 app/code/Magento/CatalogGraphQl/etc/schema.graphqls | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
index 85aeb9e6a8f10..ab3627a5852b0 100644
--- a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
+++ b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
@@ -13,7 +13,7 @@ type Query {
     product (
         id: Int @doc(description: "Id of the product.")
     ): ProductInterface
-    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductId") @doc(description: "The product query searches for product that match the criteria specified in the search and filter attributes.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductIdIdentity")
+    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductId") @doc(description: "The product query searches for product that match the specified product id.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductIdIdentity")
     category (
      id: Int @doc(description: "Id of the category.")
     ): CategoryTree

From 7c02282a8afa553f0ec71fca9650abe0c6164f26 Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Tue, 9 Jun 2020 16:13:47 +0300
Subject: [PATCH 4/7] #catalog-storefront/issue-12 Added validation for
 negative product ID

---
 .../Magento/CatalogGraphQl/Model/Resolver/ProductId.php     | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
index 8174c751982e1..e8cb0155e094f 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
@@ -62,6 +62,12 @@ public function resolve(
             );
         }
 
+        if ($productId < 0) {
+            throw new GraphQlInputException(
+                __("'id' input argument should not be negative.")
+            );
+        }
+
         /** @var \Magento\Catalog\Model\Product $product */
         $product = $this->productDataProvider->getProductById($productId, $fields);
         $data = $product->getData();

From b68976592ac1cd005f46cb39bd22977fd2461b12 Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Tue, 23 Jun 2020 16:34:09 +0300
Subject: [PATCH 5/7] #issue-12 Added ability to fetch list of products by IDs
 & GraphQl schema adjustments

---
 .../DataProvider/ProductDataProvider.php      | 21 ++++++++++-------
 .../ProductDataProviderInterface.php          | 10 ++++----
 .../Resolver/Product/ProductIdIdentity.php    |  8 +++----
 .../Model/Resolver/ProductId.php              | 23 +++++++------------
 .../CatalogGraphQl/etc/schema.graphqls        |  6 ++---
 5 files changed, 33 insertions(+), 35 deletions(-)

diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
index 0166318a0dcb6..dbbb9d4caddaa 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProvider.php
@@ -42,18 +42,23 @@ public function __construct(
     }
 
     /**
-     * Get product data by ID with full data set
+     * Get list of products by IDs with full data set
      *
-     * @param int $productId
+     * @param array $productIds
      * @param array $attributeCodes
-     * @return ProductInterface|Product
+     * @return ProductInterface[]|Product[]
      */
-    public function getProductById(int $productId, array $attributeCodes): ProductInterface
+    public function getProductByIds(array $productIds, array $attributeCodes): array
     {
-        /** @var Product $product */
-        $product = $this->productFactory->create();
-        $this->productResourceModel->load($product, $productId, $attributeCodes);
+        $products = [];
 
-        return $product;
+        foreach ($productIds as $productId) {
+            /** @var Product $product */
+            $product = $this->productFactory->create();
+            $this->productResourceModel->load($product, $productId, $attributeCodes);
+            $products[] = $product;
+        }
+
+        return $products;
     }
 }
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
index 9a00e0e1e0d21..c5a2aea864e20 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/DataProvider/ProductDataProviderInterface.php
@@ -10,16 +10,16 @@
 use Magento\Catalog\Api\Data\ProductInterface;
 
 /**
- * Provides product data by product ID.
+ * Provides product data by product IDs.
  */
 interface ProductDataProviderInterface
 {
     /**
-     * Retrieve product by product ID.
+     * Retrieve product by product IDs.
      *
-     * @param int $productId
+     * @param array $productIds
      * @param array $attributeCodes
-     * @return ProductInterface
+     * @return ProductInterface[]
      */
-    public function getProductById(int $productId, array $attributeCodes): ProductInterface;
+    public function getProductByIds(array $productIds, array $attributeCodes): array;
 }
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
index dbe24a375eade..059a51d032852 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
@@ -11,7 +11,7 @@
 use Magento\Framework\GraphQl\Query\Resolver\IdentityInterface;
 
 /**
- * Identity for resolved product by ID
+ * Identity for resolved products by IDs
  */
 class ProductIdIdentity implements IdentityInterface
 {
@@ -21,14 +21,14 @@ class ProductIdIdentity implements IdentityInterface
     private $cacheTag = Product::CACHE_TAG;
 
     /**
-     * Get product id for cache tag
+     * Get product ids for cache tag
      *
      * @param array $resolvedData
      * @return array
      */
     public function getIdentities(array $resolvedData): array
     {
-        return empty($resolvedData['id']) ?
-            [] : [$this->cacheTag, $resolvedData['id']];
+        return empty($resolvedData['ids']) ?
+            [] : [$this->cacheTag, implode('_', $resolvedData['ids'])];
     }
 }
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
index e8cb0155e094f..2f9bebb5d56e3 100644
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
@@ -53,26 +53,19 @@ public function resolve(
         array $value = null,
         array $args = null
     ) {
-        $productId = (int) ($args['id'] ?? 0);
+        $productIds = ($args['ids'] ?? []);
         $fields = $this->productFieldsSelector->getProductFieldsFromInfo($info);
 
-        if (!$productId) {
-            throw new GraphQlInputException(
-                __("'id' input argument is required.")
-            );
-        }
+        /** @var \Magento\Catalog\Model\Product[] $products */
+        $products = $this->productDataProvider->getProductByIds($productIds, $fields);
+        $data = [];
 
-        if ($productId < 0) {
-            throw new GraphQlInputException(
-                __("'id' input argument should not be negative.")
-            );
+        foreach ($products as $product) {
+            $productData = $product->getData();
+            $productData['model'] = $product;
+            $data[] = $productData;
         }
 
-        /** @var \Magento\Catalog\Model\Product $product */
-        $product = $this->productDataProvider->getProductById($productId, $fields);
-        $data = $product->getData();
-        $data['model'] = $product;
-
         return $data;
     }
 }
diff --git a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
index ab3627a5852b0..c03d9ef9c3914 100644
--- a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
+++ b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
@@ -11,9 +11,9 @@ type Query {
     ): Products
     @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\Products") @doc(description: "The products query searches for products that match the criteria specified in the search and filter attributes.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\Identity")
     product (
-        id: Int @doc(description: "Id of the product.")
-    ): ProductInterface
-    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductId") @doc(description: "The product query searches for product that match the specified product id.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductIdIdentity")
+        ids: [ID!]! @doc(description: "Product IDs.")
+    ): [ProductInterface]
+    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductId") @doc(description: "The product query fetches products that match the specified IDs.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductIdIdentity")
     category (
      id: Int @doc(description: "Id of the category.")
     ): CategoryTree

From 9539a75b484efbcb40b7c07a7c9ee6bec8d94c9b Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Wed, 24 Jun 2020 09:28:15 +0300
Subject: [PATCH 6/7] #issue-12 Refactoring the class names according to the
 new behavior & Renamed the query to productsByID

---
 .../Resolver/Product/ProductsByIdIdentity.php | 34 +++++++++
 .../Model/Resolver/ProductsByID.php           | 70 +++++++++++++++++++
 .../CatalogGraphQl/etc/schema.graphqls        |  4 +-
 3 files changed, 106 insertions(+), 2 deletions(-)
 create mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductsByIdIdentity.php
 create mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/ProductsByID.php

diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductsByIdIdentity.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductsByIdIdentity.php
new file mode 100644
index 0000000000000..9f78be9d5760a
--- /dev/null
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductsByIdIdentity.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CatalogGraphQl\Model\Resolver\Product;
+
+use Magento\Catalog\Model\Product;
+use Magento\Framework\GraphQl\Query\Resolver\IdentityInterface;
+
+/**
+ * Identity for resolved products by IDs
+ */
+class ProductsByIdIdentity implements IdentityInterface
+{
+    /**
+     * @var string
+     */
+    private $cacheTag = Product::CACHE_TAG;
+
+    /**
+     * Get product ids for cache tag
+     *
+     * @param array $resolvedData
+     * @return array
+     */
+    public function getIdentities(array $resolvedData): array
+    {
+        return empty($resolvedData['ids']) ?
+            [] : [$this->cacheTag, implode('_', $resolvedData['ids'])];
+    }
+}
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductsByID.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductsByID.php
new file mode 100644
index 0000000000000..45aa2ae05b85d
--- /dev/null
+++ b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductsByID.php
@@ -0,0 +1,70 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\CatalogGraphQl\Model\Resolver;
+
+use Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider\ProductDataProviderInterface;
+use Magento\CatalogGraphQl\Model\Resolver\Product\ProductFieldsSelector;
+use Magento\Framework\GraphQl\Config\Element\Field;
+use Magento\Framework\GraphQl\Query\ResolverInterface;
+use Magento\Framework\GraphQl\Schema\Type\ResolveInfo;
+
+/**
+ * Products by ID resolver, used for GraphQL request processing.
+ */
+class ProductsByID implements ResolverInterface
+{
+    /**
+     * @var ProductDataProviderInterface
+     */
+    private $productDataProvider;
+
+    /**
+     * @var ProductFieldsSelector
+     */
+    private $productFieldsSelector;
+
+    /**
+     * ProductsByID constructor.
+     *
+     * @param ProductDataProviderInterface $productDataProvider
+     * @param ProductFieldsSelector $productFieldsSelector
+     */
+    public function __construct(
+        ProductDataProviderInterface $productDataProvider,
+        ProductFieldsSelector $productFieldsSelector
+    ) {
+        $this->productDataProvider = $productDataProvider;
+        $this->productFieldsSelector = $productFieldsSelector;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function resolve(
+        Field $field,
+        $context,
+        ResolveInfo $info,
+        array $value = null,
+        array $args = null
+    ) {
+        $productIds = ($args['ids'] ?? []);
+        $fields = $this->productFieldsSelector->getProductFieldsFromInfo($info);
+
+        /** @var \Magento\Catalog\Model\Product[] $products */
+        $products = $this->productDataProvider->getProductByIds($productIds, $fields);
+        $data = [];
+
+        foreach ($products as $product) {
+            $productData = $product->getData();
+            $productData['model'] = $product;
+            $data[] = $productData;
+        }
+
+        return $data;
+    }
+}
diff --git a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
index c03d9ef9c3914..15c48343ac5f7 100644
--- a/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
+++ b/app/code/Magento/CatalogGraphQl/etc/schema.graphqls
@@ -10,10 +10,10 @@ type Query {
         sort: ProductAttributeSortInput @doc(description: "Specifies which attributes to sort on, and whether to return the results in ascending or descending order.")
     ): Products
     @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\Products") @doc(description: "The products query searches for products that match the criteria specified in the search and filter attributes.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\Identity")
-    product (
+    productsByID (
         ids: [ID!]! @doc(description: "Product IDs.")
     ): [ProductInterface]
-    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductId") @doc(description: "The product query fetches products that match the specified IDs.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductIdIdentity")
+    @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\ProductsByID") @doc(description: "The productsByID query fetches products that match the specified IDs.") @cache(cacheIdentity: "Magento\\CatalogGraphQl\\Model\\Resolver\\Product\\ProductsByIdIdentity")
     category (
      id: Int @doc(description: "Id of the category.")
     ): CategoryTree

From 578ea6e1528a9d1db1c580210b77f4f6aa55bcbe Mon Sep 17 00:00:00 2001
From: Sergiy Zhovnir <s.zhovnir@atwix.com>
Date: Wed, 24 Jun 2020 09:28:39 +0300
Subject: [PATCH 7/7] #issue-12 Removed unused classes

---
 .../Resolver/Product/ProductIdIdentity.php    | 34 ---------
 .../Model/Resolver/ProductId.php              | 71 -------------------
 2 files changed, 105 deletions(-)
 delete mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
 delete mode 100644 app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php

diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
deleted file mode 100644
index 059a51d032852..0000000000000
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/Product/ProductIdIdentity.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-/**
- * Copyright © Magento, Inc. All rights reserved.
- * See COPYING.txt for license details.
- */
-declare(strict_types=1);
-
-namespace Magento\CatalogGraphQl\Model\Resolver\Product;
-
-use Magento\Catalog\Model\Product;
-use Magento\Framework\GraphQl\Query\Resolver\IdentityInterface;
-
-/**
- * Identity for resolved products by IDs
- */
-class ProductIdIdentity implements IdentityInterface
-{
-    /**
-     * @var string
-     */
-    private $cacheTag = Product::CACHE_TAG;
-
-    /**
-     * Get product ids for cache tag
-     *
-     * @param array $resolvedData
-     * @return array
-     */
-    public function getIdentities(array $resolvedData): array
-    {
-        return empty($resolvedData['ids']) ?
-            [] : [$this->cacheTag, implode('_', $resolvedData['ids'])];
-    }
-}
diff --git a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php b/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
deleted file mode 100644
index 2f9bebb5d56e3..0000000000000
--- a/app/code/Magento/CatalogGraphQl/Model/Resolver/ProductId.php
+++ /dev/null
@@ -1,71 +0,0 @@
-<?php
-/**
- * Copyright © Magento, Inc. All rights reserved.
- * See COPYING.txt for license details.
- */
-declare(strict_types=1);
-
-namespace Magento\CatalogGraphQl\Model\Resolver;
-
-use Magento\CatalogGraphQl\Model\Resolver\Product\DataProvider\ProductDataProviderInterface;
-use Magento\CatalogGraphQl\Model\Resolver\Product\ProductFieldsSelector;
-use Magento\Framework\GraphQl\Config\Element\Field;
-use Magento\Framework\GraphQl\Exception\GraphQlInputException;
-use Magento\Framework\GraphQl\Query\ResolverInterface;
-use Magento\Framework\GraphQl\Schema\Type\ResolveInfo;
-
-/**
- * Product by ID resolver, used for GraphQL request processing.
- */
-class ProductId implements ResolverInterface
-{
-    /**
-     * @var ProductDataProviderInterface
-     */
-    private $productDataProvider;
-
-    /**
-     * @var ProductFieldsSelector
-     */
-    private $productFieldsSelector;
-
-    /**
-     * ProductId constructor.
-     *
-     * @param ProductDataProviderInterface $productDataProvider
-     * @param ProductFieldsSelector $productFieldsSelector
-     */
-    public function __construct(
-        ProductDataProviderInterface $productDataProvider,
-        ProductFieldsSelector $productFieldsSelector
-    ) {
-        $this->productDataProvider = $productDataProvider;
-        $this->productFieldsSelector = $productFieldsSelector;
-    }
-
-    /**
-     * @inheritdoc
-     */
-    public function resolve(
-        Field $field,
-        $context,
-        ResolveInfo $info,
-        array $value = null,
-        array $args = null
-    ) {
-        $productIds = ($args['ids'] ?? []);
-        $fields = $this->productFieldsSelector->getProductFieldsFromInfo($info);
-
-        /** @var \Magento\Catalog\Model\Product[] $products */
-        $products = $this->productDataProvider->getProductByIds($productIds, $fields);
-        $data = [];
-
-        foreach ($products as $product) {
-            $productData = $product->getData();
-            $productData['model'] = $product;
-            $data[] = $productData;
-        }
-
-        return $data;
-    }
-}