Dispatch events when tags are added/updated/deleted

lib/private/systemtag/managerfactory.php

@@ -57,7 +57,8 @@ class ManagerFactory implements ISystemTagManagerFactory {
 	 */
 	public function getManager() {
 		return new SystemTagManager(
-			$this->serverContainer->getDatabaseConnection()
+			$this->serverContainer->getDatabaseConnection(),
+			$this->serverContainer->getEventDispatcher()
 		);
 	}
 

lib/private/systemtag/systemtagmanager.php

@@ -26,17 +26,20 @@ use Doctrine\DBAL\Exception\UniqueConstraintViolationException;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 use OCP\SystemTag\ISystemTagManager;
+use OCP\SystemTag\ManagerEvent;
 use OCP\SystemTag\TagAlreadyExistsException;
 use OCP\SystemTag\TagNotFoundException;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 
 class SystemTagManager implements ISystemTagManager {
 
 	const TAG_TABLE = 'systemtag';
 
-	/**
-	 * @var IDBConnection
-	 */
-	private $connection;
+	/** @var IDBConnection */
+	protected $connection;
+
+	/** @var EventDispatcherInterface */
+	protected $dispatcher;
 
 	/**
 	 * Prepared query for selecting tags directly
@@ -46,12 +49,14 @@ class SystemTagManager implements ISystemTagManager {
 	private $selectTagQuery;
 
 	/**
-	* Constructor.
-	*
-	* @param IDBConnection $connection database connection
-	*/
-	public function __construct(IDBConnection $connection) {
+	 * Constructor.
+	 *
+	 * @param IDBConnection $connection database connection
+	 * @param EventDispatcherInterface $dispatcher
+	 */
+	public function __construct(IDBConnection $connection, EventDispatcherInterface $dispatcher) {
 		$this->connection = $connection;
+		$this->dispatcher = $dispatcher;
 
 		$query = $this->connection->getQueryBuilder();
 		$this->selectTagQuery = $query->select('*')
@@ -190,14 +195,20 @@ class SystemTagManager implements ISystemTagManager {
 			);
 		}
 
-		$tagId = $this->connection->lastInsertId('*PREFIX*' . self::TAG_TABLE);
+		$tagId = $query->getLastInsertId();
 
-		return new SystemTag(
+		$tag = new SystemTag(
 			(int)$tagId,
 			$tagName,
 			(bool)$userVisible,
 			(bool)$userAssignable
 		);
+
+		$this->dispatcher->dispatch(ManagerEvent::EVENT_CREATE, new ManagerEvent(
+			ManagerEvent::EVENT_CREATE, $tag
+		));
+
+		return $tag;
 	}
 
 	/**
@@ -207,6 +218,22 @@ class SystemTagManager implements ISystemTagManager {
 		$userVisible = (int)$userVisible;
 		$userAssignable = (int)$userAssignable;
 
+		try {
+			$tags = $this->getTagsByIds($tagId);
+		} catch (TagNotFoundException $e) {
+			throw new TagNotFoundException(
+				'Tag does not exist', 0, null, [$tagId]
+			);
+		}
+
+		$beforeUpdate = array_shift($tags);
+		$afterUpdate = new SystemTag(
+			(int) $tagId,
+			$tagName,
+			(bool) $userVisible,
+			(bool) $userAssignable
+		);
+
 		$query = $this->connection->getQueryBuilder();
 		$query->update(self::TAG_TABLE)
 			->set('name', $query->createParameter('name'))
@@ -231,6 +258,10 @@ class SystemTagManager implements ISystemTagManager {
 				$e
 			);
 		}
+
+		$this->dispatcher->dispatch(ManagerEvent::EVENT_UPDATE, new ManagerEvent(
+			ManagerEvent::EVENT_UPDATE, $afterUpdate, $beforeUpdate
+		));
 	}
 
 	/**
@@ -242,10 +273,21 @@ class SystemTagManager implements ISystemTagManager {
 		}
 
 		$tagNotFoundException = null;
+		$tags = [];
 		try {
-			$this->getTagsByIds($tagIds);
+			$tags = $this->getTagsByIds($tagIds);
 		} catch (TagNotFoundException $e) {
 			$tagNotFoundException = $e;
+
+			// Get existing tag objects for the hooks later
+			$existingTags = array_diff($tagIds, $tagNotFoundException->getMissingTags());
+			if (!empty($existingTags)) {
+				try {
+					$tags = $this->getTagsByIds($existingTags);
+				} catch (TagNotFoundException $e) {
+					// Ignore further errors...
+				}
+			}
 		}
 
 		// delete relationships first
@@ -261,6 +303,12 @@ class SystemTagManager implements ISystemTagManager {
 			->setParameter('tagids', $tagIds, IQueryBuilder::PARAM_INT_ARRAY)
 			->execute();
 
+		foreach ($tags as $tag) {
+			$this->dispatcher->dispatch(ManagerEvent::EVENT_DELETE, new ManagerEvent(
+				ManagerEvent::EVENT_DELETE, $tag
+			));
+		}
+
 		if ($tagNotFoundException !== null) {
 			throw new TagNotFoundException(
 				'Tag id(s) not found', 0, $tagNotFoundException, $tagNotFoundException->getMissingTags()

lib/public/systemtag/managerevent.php

@@ -0,0 +1,85 @@
+<?php
+/**
+ * @author Joas Schilling <nickvergessen@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCP\SystemTag;
+
+use Symfony\Component\EventDispatcher\Event;
+
+/**
+ * Class ManagerEvent
+ *
+ * @package OCP\SystemTag
+ * @since 9.0.0
+ */
+class ManagerEvent extends Event {
+
+	const EVENT_CREATE = 'OCP\SystemTag\ISystemTagManager::createTag';
+	const EVENT_UPDATE = 'OCP\SystemTag\ISystemTagManager::updateTag';
+	const EVENT_DELETE = 'OCP\SystemTag\ISystemTagManager::deleteTag';
+
+	/** @var string */
+	protected $event;
+	/** @var ISystemTag */
+	protected $tag;
+	/** @var ISystemTag */
+	protected $beforeTag;
+
+	/**
+	 * DispatcherEvent constructor.
+	 *
+	 * @param string $event
+	 * @param ISystemTag $tag
+	 * @param ISystemTag $beforeTag
+	 * @since 9.0.0
+	 */
+	public function __construct($event, ISystemTag $tag, ISystemTag $beforeTag = null) {
+		$this->event = $event;
+		$this->tag = $tag;
+		$this->beforeTag = $beforeTag;
+	}
+
+	/**
+	 * @return string
+	 * @since 9.0.0
+	 */
+	public function getEvent() {
+		return $this->event;
+	}
+
+	/**
+	 * @return ISystemTag
+	 * @since 9.0.0
+	 */
+	public function getTag() {
+		return $this->tag;
+	}
+
+	/**
+	 * @return ISystemTag
+	 * @since 9.0.0
+	 */
+	public function getTagBefore() {
+		if ($this->event !== self::EVENT_UPDATE) {
+			throw new \BadMethodCallException('getTagBefore is only available on the update Event');
+		}
+		return $this->beforeTag;
+	}
+}

tests/lib/systemtag/systemtagmanagertest.php

@@ -15,6 +15,7 @@ use OC\SystemTag\SystemTagObjectMapper;
 use OCP\IDBConnection;
 use OCP\SystemTag\ISystemTag;
 use OCP\SystemTag\ISystemTagManager;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Test\TestCase;
 
 /**
@@ -35,11 +36,23 @@ class SystemTagManagerTest extends TestCase {
 	 */
 	private $connection;
 
+	/**
+	 * @var EventDispatcherInterface
+	 */
+	private $dispatcher;
+
 	public function setUp() {
 		parent::setUp();
 
 		$this->connection = \OC::$server->getDatabaseConnection();
-		$this->tagManager = new SystemTagManager($this->connection);
+
+		$this->dispatcher = $this->getMockBuilder('Symfony\Component\EventDispatcher\EventDispatcherInterface')
+			->getMock();
+
+		$this->tagManager = new SystemTagManager(
+			$this->connection,
+			$this->dispatcher
+		);
 		$this->pruneTagsTables();
 	}