Issue #2076033 by juampy: Fixed PHP warning when looking if a REST resource...

Issue #2076033 by juampy: Fixed PHP warning when looking if a REST resource defines authentication providers.

core/modules/rest/lib/Drupal/rest/EventSubscriber/RouteSubscriber.php

@@ -74,7 +74,7 @@ public function dynamicRoutes(RouteBuildEvent $event) {
           }
           // Check if there are authentication provider restrictions in the
           // configuration and apply them to the route.
-          if (is_array($enabled_methods[$method]['supported_auth']) && !empty($enabled_methods[$method]['supported_auth'])) {
+          if (!empty($enabled_methods[$method]['supported_auth']) && is_array($enabled_methods[$method]['supported_auth'])) {
             $route->setOption('_auth', $enabled_methods[$method]['supported_auth']);
           }
           // If there is no format requirement or if it matches the

core/modules/rest/lib/Drupal/rest/Tests/ReadTest.php

@@ -95,4 +95,27 @@ public function testRead() {
     $this->assertResponse(404);
     $this->assertNull(drupal_json_decode($response), 'No valid JSON found.');
   }
+
+  /**
+   * Tests the resource structure.
+   */
+  public function testResourceStructure() {
+    // Enable a service with a format restriction but no authentication.
+    $this->enableService('entity:node', 'GET', 'json');
+    // Create a user account that has the required permissions to read
+    // resources via the REST API.
+    $permissions = $this->entityPermissions('node', 'view');
+    $permissions[] = 'restful get entity:node';
+    $account = $this->drupalCreateUser($permissions);
+    $this->drupalLogin($account);
+
+    // Create an entity programmatically.
+    $entity = $this->entityCreate('node');
+    $entity->save();
+
+    // Read it over the REST API.
+    $response = $this->httpRequest('entity/node/' . $entity->id(), 'GET', NULL, 'application/json');
+    $this->assertResponse('200', 'HTTP response code is correct.');
+  }
+
 }