Added a separate resolver for returning category products count

Author: rogyar

app/code/Magento/CatalogGraphQl/Model/Category/Hydrator.php

@@ -52,7 +52,6 @@ public function hydrateCategory(Category $category, $basicFieldsOnly = false) :
             $categoryData = $category->getData();
         } else {
             $categoryData = $this->dataObjectProcessor->buildOutputDataArray($category, CategoryInterface::class);
-            $categoryData['product_count'] = $category->getProductCount();
         }
         $categoryData['id'] = $category->getId();
         $categoryData['children'] = [];

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

@@ -65,7 +65,7 @@ public function resolve(
                 'eq' => $value['id']
             ]
         ];
-        $searchCriteria = $this->searchCriteriaBuilder->build($field->getName(), $args);
+            $searchCriteria = $this->searchCriteriaBuilder->build($field->getName(), $args);
         $searchCriteria->setCurrentPage($args['currentPage']);
         $searchCriteria->setPageSize($args['pageSize']);
         $searchResult = $this->filterQuery->getResult($searchCriteria, $info);

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

@@ -379,7 +379,7 @@ interface CategoryInterface @typeResolver(class: "Magento\\CatalogGraphQl\\Model
     level: Int @doc(description: "Indicates the depth of the category within the tree")
     created_at: String @doc(description: "Timestamp indicating when the category was created")
     updated_at: String @doc(description: "Timestamp indicating when the category was updated")
-    product_count: Int @doc(description: "The number of products in the category")
+    product_count: Int @doc(description: "The number of products in the category") @resolver(class: "Magento\\CatalogGraphQl\\Model\\Resolver\\Category\\ProductsCount")
     default_sort_by: String @doc(description: "The attribute to use for sorting")
     products(
         pageSize: Int = 20 @doc(description: "Specifies the maximum number of results to return at once. This attribute is optional."),