GraphQL - Added sort by options to Products GraphQL type

app/code/Magento/CatalogGraphQl/Model/Resolver/Products.php

@@ -53,27 +53,42 @@ class Products implements ResolverInterface
      * @var Layer\DataProvider\Filters
      */
     private $filtersDataProvider;
+
+    /**
+     * @var \Magento\Catalog\Model\Config
+     */
+    private $catalogConfig;
+
+    /**
+     * @var \Magento\Store\Model\StoreManagerInterface
+     */
+    private $storeManager;
 
     /**
      * @param Builder $searchCriteriaBuilder
      * @param Search $searchQuery
      * @param Filter $filterQuery
      * @param ValueFactory $valueFactory
+     * @param \Magento\Catalog\Model\Config $catalogConfig
      */
     public function __construct(
         Builder $searchCriteriaBuilder,
         Search $searchQuery,
         Filter $filterQuery,
         SearchFilter $searchFilter,
         ValueFactory $valueFactory,
-        \Magento\CatalogGraphQl\Model\Resolver\Layer\DataProvider\Filters $filtersDataProvider
+        \Magento\CatalogGraphQl\Model\Resolver\Layer\DataProvider\Filters $filtersDataProvider,
+        \Magento\Catalog\Model\Config $catalogConfig,
+        \Magento\Store\Model\StoreManagerInterface $storeManager
     ) {
         $this->searchCriteriaBuilder = $searchCriteriaBuilder;
         $this->searchQuery = $searchQuery;
         $this->filterQuery = $filterQuery;
         $this->searchFilter = $searchFilter;
         $this->valueFactory = $valueFactory;
         $this->filtersDataProvider = $filtersDataProvider;
+        $this->catalogConfig = $catalogConfig;
+        $this->storeManager = $storeManager;
     }
 
     /**
@@ -118,14 +133,28 @@ public function resolve(
             );
         }
 
+        $options = $this->catalogConfig->getAttributeUsedForSortByArray();
+
+        $sortFields = [
+            'default' => $this->catalogConfig->getProductListDefaultSortBy($this->storeManager->getStore()->getId()),
+            'options' => []
+        ];
+
+        $sortFields['options'][] = ['key' => 'position', 'label' => 'Position'];
+        foreach ($this->catalogConfig->getAttributesUsedForSortBy() as $attribute) {
+            $sortFields['options'][] = ['key' => $attribute->getAttributeCode(), 'label' => $attribute->getStoreLabel()];
+        }
+
         $data = [
             'total_count' => $searchResult->getTotalCount(),
             'items' => $searchResult->getProductsSearchResult(),
             'page_info' => [
                 'page_size' => $searchCriteria->getPageSize(),
-                'current_page' => $currentPage
+                'current_page' => $currentPage,
+                'sort_fields' => $sortFields,
             ],
-            'filters' => $this->filtersDataProvider->getData($layerType)
+            'filters' => $this->filtersDataProvider->getData($layerType),
+
         ];
 
         $result = function () use ($data) {

app/code/Magento/GraphQl/etc/schema.graphqls

@@ -25,9 +25,20 @@ input FilterTypeInput @doc(description: "FilterTypeInput specifies which action
 type SearchResultPageInfo @doc(description: "SearchResultPageInfo provides navigation for the query response") {
     page_size: Int @doc(description: "Specifies the maximum number of items to return")
     current_page: Int @doc(description: "Specifies which page of results to return")
+    sort_fields: SortFields @doc(description: "An object that includes the default sort field and all available sort fields")
 }
 
 enum SortEnum @doc(description: "This enumeration indicates whether to return results in ascending or descending order") {
     ASC
     DESC
 }
+
+type SortField {
+    key: String @doc(description: "Attribute code of sort field")
+    label: String @doc(description: "Label of sort field")
+}
+
+type SortFields @doc(description: "SortFields contains a default value for sort fields and all available sort fields") {
+    default: String @doc(description: "Default value of sort fields")
+    options: [SortField] @doc(description: "Available sort fields")
+}

dev/tests/api-functional/testsuite/Magento/GraphQl/Catalog/ProductSearchTest.php

@@ -511,6 +511,15 @@ public function testQueryProductsInCurrentPageSortedByPriceASC()
         {
           page_size
           current_page
+          sort_fields 
+          {
+            default
+            options 
+            {
+                key
+                label
+            }
+          }
         }
     }
 }
@@ -530,6 +539,10 @@ public function testQueryProductsInCurrentPageSortedByPriceASC()
         $this->assertProductItems($filteredChildProducts, $response);
         $this->assertEquals(4, $response['products']['page_info']['page_size']);
         $this->assertEquals(1, $response['products']['page_info']['current_page']);
+        $this->assertArrayHasKey('sort_fields', $response['products']['page_info']);
+        $this->assertArrayHasKey('options', $response['products']['page_info']['sort_fields']);
+        $this->assertArrayHasKey('default', $response['products']['page_info']['sort_fields']);
+        $this->assertEquals('position', $response['products']['page_info']['sort_fields']['default']);
     }
 
     /**