MAGETWO-69825: [GITHUB #9891] Subcategory "liquid-hand-soap" is not opened in category "soap"

- Implemented validation URL key during category creation

Author: vital-pantsialeyeu

app/code/Magento/CatalogUrlRewrite/Observer/CategoryUrlPathAutogeneratorObserver.php

@@ -48,22 +48,31 @@ class CategoryUrlPathAutogeneratorObserver implements ObserverInterface
      */
     private $categoryRepository;
 
+    /**
+     * @var \Magento\Backend\App\Area\FrontNameResolver
+     */
+    private $frontNameResolver;
+
     /**
      * @param CategoryUrlPathGenerator $categoryUrlPathGenerator
      * @param ChildrenCategoriesProvider $childrenCategoriesProvider
      * @param \Magento\CatalogUrlRewrite\Service\V1\StoreViewService $storeViewService
      * @param CategoryRepositoryInterface $categoryRepository
+     * @param \Magento\Backend\App\Area\FrontNameResolver $frontNameResolver
      */
     public function __construct(
         CategoryUrlPathGenerator $categoryUrlPathGenerator,
         ChildrenCategoriesProvider $childrenCategoriesProvider,
         StoreViewService $storeViewService,
-        CategoryRepositoryInterface $categoryRepository
+        CategoryRepositoryInterface $categoryRepository,
+        \Magento\Backend\App\Area\FrontNameResolver $frontNameResolver = null
     ) {
         $this->categoryUrlPathGenerator = $categoryUrlPathGenerator;
         $this->childrenCategoriesProvider = $childrenCategoriesProvider;
         $this->storeViewService = $storeViewService;
         $this->categoryRepository = $categoryRepository;
+        $this->frontNameResolver = $frontNameResolver ?: \Magento\Framework\App\ObjectManager::getInstance()
+            ->get(\Magento\Backend\App\Area\FrontNameResolver::class);
     }
 
     /**
@@ -102,12 +111,12 @@ private function updateUrlKey($category, $urlKey)
             throw new \Magento\Framework\Exception\LocalizedException(__('Invalid URL key'));
         }
 
-        if (in_array($urlKey, $this->invalidValues)) {
+        if (in_array($urlKey, $this->getInvalidValues())) {
             throw new \Magento\Framework\Exception\LocalizedException(
                 __(
                     'URL key "%1" conflicts with reserved endpoint names: %2. Try another url key.',
                     $urlKey,
-                    implode(', ', $this->invalidValues)
+                    implode(', ', $this->getInvalidValues())
                 )
             );
         }
@@ -122,6 +131,16 @@ private function updateUrlKey($category, $urlKey)
         }
     }
 
+    /**
+     * Get reserved endpoint names.
+     *
+     * @return array
+     */
+    private function getInvalidValues()
+    {
+        return array_unique(array_merge($this->invalidValues, [$this->frontNameResolver->getFrontName()]));
+    }
+
     /**
      * Update url path for children category.
      *