MAGETWO-60037: User is able to create empty URL key for category which leads to numerous errors

Author: le0n4eg

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

@@ -5,6 +5,7 @@
  */
 namespace Magento\CatalogUrlRewrite\Observer;
 
+use Doctrine\Instantiator\Exception\InvalidArgumentException;
 use Magento\Catalog\Model\Category;
 use Magento\CatalogUrlRewrite\Model\CategoryUrlPathGenerator;
 use Magento\CatalogUrlRewrite\Service\V1\StoreViewService;
@@ -42,13 +43,18 @@ public function __construct(
     /**
      * @param \Magento\Framework\Event\Observer $observer
      * @return void
+     * @throws \Magento\Framework\Exception\LocalizedException
      */
     public function execute(\Magento\Framework\Event\Observer $observer)
     {
         /** @var Category $category */
         $category = $observer->getEvent()->getCategory();
         if ($category->getUrlKey() !== false) {
-            $category->setUrlKey($this->categoryUrlPathGenerator->getUrlKey($category))
+            $resultUrlKey = $this->categoryUrlPathGenerator->getUrlKey($category);
+            if (empty($resultUrlKey)) {
+                throw new \Magento\Framework\Exception\LocalizedException(__('Invalid URL key'));
+            }
+            $category->setUrlKey($resultUrlKey)
                 ->setUrlPath($this->categoryUrlPathGenerator->getUrlPath($category));
             if (!$category->isObjectNew()) {
                 $category->getResource()->saveAttribute($category, 'url_path');

dev/tests/integration/testsuite/Magento/CatalogUrlRewrite/Model/CategoryUrlRewriteGeneratorTest.php

@@ -25,13 +25,6 @@ protected function setUp()
         $this->objectManager = \Magento\TestFramework\Helper\Bootstrap::getObjectManager();
     }
 
-    public function tearDown()
-    {
-        $category = $this->objectManager->create(\Magento\Catalog\Model\Category::class);
-        $category->load(3);
-        $category->delete();
-    }
-
     /**
      * @magentoDataFixture Magento/CatalogUrlRewrite/_files/categories.php
      * @magentoDbIsolation enabled
@@ -96,6 +89,37 @@ public function testGenerateUrlRewritesWithSaveHistory()
         $this->assertResults($categoryExpectedResult, $actualResults);
     }
 
+    /**
+     * @magentoDataFixture Magento/CatalogUrlRewrite/_files/categories.php
+     * @magentoDbIsolation enabled
+     * @magentoAppIsolation enabled
+     * @param string $urlKey
+     * @dataProvider IncorrectUrlRewritesDataProvider
+     */
+    public function testGenerateUrlRewritesWithIncorrectUrlKey($urlKey)
+    {
+        $this->setExpectedException(
+            \Magento\Framework\Exception\LocalizedException::class,
+            'Invalid URL key'
+        );
+        /** @var \Magento\Catalog\Api\CategoryRepositoryInterface $repository */
+        $repository = $this->objectManager->get(\Magento\Catalog\Api\CategoryRepositoryInterface::class);
+        $category = $repository->get(3);
+        $category->setUrlKey($urlKey);
+        $repository->save($category);
+    }
+
+    /**
+     * @return array
+     */
+    public function IncorrectUrlRewritesDataProvider()
+    {
+        return [
+            ['#'],
+            ['//']
+        ];
+    }
+
     /**
      * @param array $filter
      * @return array