Clean-up REST resource generator

Author: Chi-teck

templates/plugin/rest-resource/rest-resource.twig

@@ -2,15 +2,12 @@
 
 namespace Drupal\{{ machine_name }}\Plugin\rest\resource;
 
-use Drupal\Component\Plugin\DependentPluginInterface;
-use Drupal\Core\Database\Connection;
-use Drupal\Core\Routing\BcRoute;
+use Drupal\Core\KeyValueStore\KeyValueFactoryInterface;
 use Drupal\rest\ModifiedResourceResponse;
 use Drupal\rest\Plugin\ResourceBase;
 use Drupal\rest\ResourceResponse;
 use Psr\Log\LoggerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 
 /**
@@ -26,43 +23,49 @@ use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
  * )
  *
  * @DCG
- * This plugin exposes database records as REST resources. In order to enable it
- * import the resource configuration into active configuration storage. You may
- * find an example of such configuration in the following file:
+ * The plugin exposes key-value records as REST resources. In order to enable it
+ * import the resource configuration into active configuration storage. An
+ * example of such configuration can be located in the following file:
  * core/modules/rest/config/optional/rest.resource.entity.node.yml.
- * Alternatively you can make use of REST UI module.
+ * Alternatively you can enable it through admin interface provider by REST UI
+ * module.
  * @see https://www.drupal.org/project/restui
- * For accessing Drupal entities through REST interface use
- * \Drupal\rest\Plugin\rest\resource\EntityResource plugin.
+ *
+ * @DCG
+ * Notice that this plugin does not provide any validation for the data.
+ * Consider creating custom normalizer to validate and normalize the incoming
+ * data. It can be enabled in the plugin definition as follows.
+ * @code
+ *   serialization_class = "Drupal\foo\MyDataStructure",
+ * @endcode
+ *
+ * @DCG
+ * For entities, it is recommended to use REST resource plugin provided by
+ * Drupal core.
+ * @see \Drupal\rest\Plugin\rest\resource\EntityResource
  */
-class {{ class }} extends ResourceBase implements DependentPluginInterface {
+class {{ class }} extends ResourceBase {
 
   /**
-   * The database connection.
+   * The key-value storage.
    *
-   * @var \Drupal\Core\Database\Connection
+   * @var \Drupal\Core\KeyValueStore\KeyValueStoreInterface
    */
-  protected $dbConnection;
+  protected $storage;
 
   /**
-   * Constructs a Drupal\rest\Plugin\rest\resource\EntityResource object.
-   *
-   * @param array $configuration
-   *   A configuration array containing information about the plugin instance.
-   * @param string $plugin_id
-   *   The plugin_id for the plugin instance.
-   * @param mixed $plugin_definition
-   *   The plugin implementation definition.
-   * @param array $serializer_formats
-   *   The available serialization formats.
-   * @param \Psr\Log\LoggerInterface $logger
-   *   A logger instance.
-   * @param \Drupal\Core\Database\Connection $db_connection
-   *   The database connection.
+   * {@inheritdoc}
    */
-  public function __construct(array $configuration, $plugin_id, $plugin_definition, array $serializer_formats, LoggerInterface $logger, Connection $db_connection) {
-    parent::__construct($configuration, $plugin_id, $plugin_definition, $serializer_formats, $logger);
-    $this->dbConnection = $db_connection;
+  public function __construct(
+    array $configuration,
+    $plugin_id,
+    $plugin_definition,
+    array $serializer_formats,
+    LoggerInterface $logger,
+    KeyValueFactoryInterface $keyValueFactory,
+  ) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition, $serializer_formats, $logger, $keyValueFactory);
+    $this->storage = $keyValueFactory->get('{{ plugin_id }}');
   }
 
   /**
@@ -75,88 +78,81 @@ class {{ class }} extends ResourceBase implements DependentPluginInterface {
       $plugin_definition,
       $container->getParameter('serializer.formats'),
       $container->get('logger.factory')->get('rest'),
-      $container->get('database')
+      $container->get('keyvalue')
     );
   }
 
   /**
-   * Responds to GET requests.
-   *
-   * @param int $id
-   *   The ID of the record.
+   * Responds to POST requests and saves the new record.
    *
-   * @return \Drupal\rest\ResourceResponse
-   *   The response containing the record.
+   * @param array $data
+   *   Data to write into the database.
    *
-   * @throws \Symfony\Component\HttpKernel\Exception\HttpException
+   * @return \Drupal\rest\ModifiedResourceResponse
+   *   The HTTP response object.
    */
-  public function get($id) {
-    return new ResourceResponse($this->loadRecord($id));
+  public function post(array $data) {
+    $data['id'] = $this->getNextId();
+    $this->storage->set($data['id'], $data);
+    $this->logger->notice('Create new {{ plugin_label|lower }} record @id.');
+    // Return the newly created record in the response body.
+    return new ModifiedResourceResponse($data, 201);
   }
 
   /**
-   * Responds to POST requests and saves the new record.
+   * Responds to GET requests.
    *
-   * @param mixed $data
-   *   Data to write into the database.
+   * @param int $id
+   *   The ID of the record.
    *
-   * @return \Drupal\rest\ModifiedResourceResponse
-   *   The HTTP response object.
+   * @return \Drupal\rest\ResourceResponse
+   *   The response containing the record.
    */
-  public function post($data) {
-
-    $this->validate($data);
-
-    $id = $this->dbConnection->insert('{{ plugin_id }}')
-      ->fields($data)
-      ->execute();
-
-    $this->logger->notice('New {{ plugin_label|lower }} record has been created.');
-
-    $created_record = $this->loadRecord($id);
-
-    // Return the newly created record in the response body.
-    return new ModifiedResourceResponse($created_record, 201);
+  public function get($id) {
+    if (!$this->storage->has($id)) {
+      throw new NotFoundHttpException();
+    }
+    $resource = $this->storage->get($id);
+    return new ResourceResponse($resource);
   }
 
   /**
-   * Responds to entity PATCH requests.
+   * Responds to PATCH requests.
    *
    * @param int $id
    *   The ID of the record.
-   * @param mixed $data
-   *   Data to write into the database.
+   * @param array $data
+   *   Data to write into the storage.
    *
    * @return \Drupal\rest\ModifiedResourceResponse
    *   The HTTP response object.
    */
-  public function patch($id, $data) {
-    $this->validate($data);
-    return $this->updateRecord($id, $data);
+  public function patch($id, array $data) {
+    if (!$this->storage->has($id)) {
+      throw new NotFoundHttpException();
+    }
+    $stored_data = $this->storage->get($id);
+    $data += $stored_data;
+    $this->storage->set($id, $data);
+    $this->logger->notice('The {{ plugin_label|lower }} record @id has been updated.');
+    return new ModifiedResourceResponse($data, 200);
   }
 
   /**
-   * Responds to entity DELETE requests.
+   * Responds to DELETE requests.
    *
    * @param int $id
    *   The ID of the record.
    *
    * @return \Drupal\rest\ModifiedResourceResponse
    *   The HTTP response object.
-   *
-   * @throws \Symfony\Component\HttpKernel\Exception\HttpException
    */
   public function delete($id) {
-
-    // Make sure the record still exists.
-    $this->loadRecord($id);
-
-    $this->dbConnection->delete('{{ plugin_id }}')
-      ->condition('id', $id)
-      ->execute();
-
-    $this->logger->notice('{{ plugin_label }} record @id has been deleted.', ['@id' => $id]);
-
+    if (!$this->storage->has($id)) {
+      throw new NotFoundHttpException();
+    }
+    $this->storage->delete($id);
+    $this->logger->notice('The {{ plugin_label|lower }} record @id has been deleted.', ['@id' => $id]);
     // Deleted responses have an empty body.
     return new ModifiedResourceResponse(NULL, 204);
   }
@@ -166,119 +162,19 @@ class {{ class }} extends ResourceBase implements DependentPluginInterface {
    */
   protected function getBaseRoute($canonical_path, $method) {
     $route = parent::getBaseRoute($canonical_path, $method);
-
-    // Change ID validation pattern.
+    // Set ID validation pattern.
     if ($method != 'POST') {
       $route->setRequirement('id', '\d+');
     }
-
     return $route;
   }
 
   /**
-   * {@inheritdoc}
-   */
-  public function calculateDependencies() {
-    return [];
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function routes() {
-    $collection = parent::routes();
-
-    // Take out BC routes added in base class.
-    // @see https://www.drupal.org/node/2865645
-    // @todo Remove this in Drupal 9.
-    foreach ($collection as $route_name => $route) {
-      if ($route instanceof BcRoute) {
-        $collection->remove($route_name);
-      }
-    }
-
-    return $collection;
-  }
-
-  /**
-   * Validates incoming record.
-   *
-   * @param mixed $record
-   *   Data to validate.
-   *
-   * @throws \Symfony\Component\HttpKernel\Exception\BadRequestHttpException
-   */
-  protected function validate($record) {
-    if (!is_array($record) || count($record) == 0) {
-      throw new BadRequestHttpException('No record content received.');
-    }
-
-    $allowed_fields = [
-      'title',
-      'description',
-      'price',
-    ];
-
-    if (count(array_diff(array_keys($record), $allowed_fields)) > 0) {
-      throw new BadRequestHttpException('Record structure is not correct.');
-    }
-
-    if (empty($record['title'])) {
-      throw new BadRequestHttpException('Title is required.');
-    }
-    elseif (isset($record['title']) && strlen($record['title']) > 255) {
-      throw new BadRequestHttpException('Title is too big.');
-    }
-    // @DCG Add more validation rules here.
-  }
-
-  /**
-   * Loads record from database.
-   *
-   * @param int $id
-   *   The ID of the record.
-   *
-   * @return array
-   *   The database record.
-   *
-   * @throws \Symfony\Component\HttpKernel\Exception\NotFoundHttpException
+   * Returns next available ID.
    */
-  protected function loadRecord($id) {
-    $record = $this->dbConnection->query('SELECT * FROM {{ '{' }}{{ plugin_id }}{{ '}' }} WHERE id = :id', [':id' => $id])->fetchAssoc();
-    if (!$record) {
-      throw new NotFoundHttpException('The record was not found.');
-    }
-    return $record;
-  }
-
-  /**
-   * Updates record.
-   *
-   * @param int $id
-   *   The ID of the record.
-   * @param array $record
-   *   The record to validate.
-   *
-   * @return \Drupal\rest\ModifiedResourceResponse
-   *   The HTTP response object.
-   */
-  protected function updateRecord($id, array $record) {
-
-    // Make sure the record already exists.
-    $this->loadRecord($id);
-
-    $this->validate($record);
-
-    $this->dbConnection->update('{{ plugin_id }}')
-      ->fields($record)
-      ->condition('id', $id)
-      ->execute();
-
-    $this->logger->notice('{{ plugin_label }} record @id has been updated.', ['@id' => $id]);
-
-    // Return the updated record in the response body.
-    $updated_record = $this->loadRecord($id);
-    return new ModifiedResourceResponse($updated_record, 200);
+  private function getNextId() {
+    $ids = \array_keys($this->storage->getAll());
+    return count($ids) > 0 ? max($ids) + 1 : 1;
   }
 
 }