Add a janitor job to tidy log and watch tables from old entries

Signed-off-by: dartcafe <github@dartcafe.de>

appinfo/info.xml

@@ -27,6 +27,7 @@
     </dependencies>
 	<background-jobs>
 		<job>OCA\Polls\Cron\NotificationCron</job>
+        <job>OCA\Polls\Cron\JanitorCron</job>
 	</background-jobs>
 	<commands>
 		<command>OCA\Polls\Command\Share\Add</command>

lib/Cron/JanitorCron.php

@@ -0,0 +1,55 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Vinzenz Rosenkranz <vinzenz.rosenkranz@gmail.com>
+ *
+ * @author René Gieling <github@dartcafe.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as
+ *  published by the Free Software Foundation, either version 3 of the
+ *  License, or (at your option) any later version.
+ *
+ *  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
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Polls\Cron;
+
+use OCP\BackgroundJob\TimedJob;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCA\Polls\Db\LogMapper;
+use OCA\Polls\Db\WatchMapper;
+
+class JanitorCron extends TimedJob {
+
+	/** @var LogMapper */
+	private $logMapper;
+
+	/** @var WatchMapper */
+	private $watchMapper;
+
+	public function __construct(
+		ITimeFactory $time,
+		LogMapper $logMapper,
+		WatchMapper $watchMapper
+	) {
+        parent::__construct($time);
+		$this->logMapper = $logMapper;
+		$this->watchMapper = $watchMapper;
+		parent::setInterval(86400); // run once a day
+	}
+
+	protected function run($arguments) {
+		$this->logMapper->deleteProcessedEntries(); // delete processed log entries
+		$this->logMapper->deleteOldEntries(time() - (86400 * 7)); // delete entries older than 7 days
+		$this->watchMapper->deleteOldEntries(time() - 86400); // delete entries older than 1 day
+	}
+}

lib/Db/LogMapper.php

@@ -158,4 +158,30 @@ class LogMapper extends QBMapper {
 			->setParameter('userId', $userId);
 		$query->execute();
 	}
+
+	/**
+	 * Delete entries per timestamp
+	 * @return void
+	 */
+	public function deleteOldEntries(int $offset): void {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where(
+				$query->expr()->lt('created', $query->createNamedParameter($offset))
+			);
+		$query->execute();
+	}
+
+	/**
+	 * Delete processed entries
+	 * @return void
+	 */
+	public function deleteProcessedEntries(): void {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where(
+				$query->expr()->gt('processed', $query->createNamedParameter(0))
+			);
+		$query->execute();
+	}
 }

lib/Db/WatchMapper.php

@@ -70,4 +70,17 @@ class WatchMapper extends QBMapper {
 
 		return $this->findEntity($qb);
 	}
+
+	/**
+	 * Delete entries per timestamp
+	 * @return void
+	 */
+	public function deleteOldEntries(int $offset): void {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where(
+				$query->expr()->lt('updated', $query->createNamedParameter($offset))
+			);
+		$query->execute();
+	}
 }