feat: previews are physically deleted from disk and db in an async ma…

…nner

apps/files/appinfo/info.xml

@@ -22,6 +22,7 @@
 		<job>OCA\Files\BackgroundJob\DeleteOrphanedItems</job>
 		<job>OCA\Files\BackgroundJob\CleanupFileLocks</job>
 		<job>OCA\Files\BackgroundJob\CleanupPersistentFileLocks</job>
+		<job>OCA\Files\BackgroundJob\PreviewCleanupJob</job>
 	</background-jobs>
 
 	<commands>

apps/files/lib/BackgroundJob/PreviewCleanupJob.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace OCA\Files\BackgroundJob;
+
+use OC\BackgroundJob\TimedJob;
+use OC\PreviewCleanup;
+
+class PreviewCleanupJob extends TimedJob {
+	public function __construct() {
+		$this->setInterval(3600); //execute job every hour
+	}
+
+	public function run($arguments) {
+		$cmd = new PreviewCleanup(\OC::$server->getDatabaseConnection());
+		$count = $cmd->process(false, 10);
+		$logger = \OC::$server->getLogger();
+		$logger->info("$count orphaned previews deleted");
+	}
+}

apps/files_sharing/ajax/publicpreview.php

@@ -105,12 +105,8 @@
 	exit;
 }
 
-// $path is relative to the data directory but Preview expects it to be relative to the user's
-// so strip the first component
-$root = \substr($path, \strpos($path, '/') + 1);
-
 try {
-	$preview = new \OC\Preview($userId, $root);
+	$preview = new \OC\Preview($userId);
 	$preview->setFile($sharedFile);
 	$preview->setMaxX($maxX);
 	$preview->setMaxY($maxY);

core/Command/Previews/Cleanup.php

@@ -0,0 +1,68 @@
+<?php
+/**
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ *
+ * @copyright Copyright (c) 2022, ownCloud GmbH
+ * @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 OC\Core\Command\Previews;
+
+use Doctrine\DBAL\Platforms\MySqlPlatform;
+use Doctrine\DBAL\Platforms\OraclePlatform;
+use OC\Core\Command\Base;
+use OC\PreviewCleanup;
+use OCP\Files\Folder;
+use OCP\IDBConnection;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+class Cleanup extends Base {
+
+	/**
+	 * @var IDBConnection
+	 */
+	private $connection;
+
+	public function __construct(IDBConnection $connection) {
+		parent::__construct();
+		$this->connection = $connection;
+	}
+
+	protected function configure() {
+		parent::configure();
+
+		$this
+			->setName('previews:cleanup')
+			->setDescription('Remove unreferenced previews')
+			->addOption('all')
+			->addArgument('chunk_size', InputArgument::OPTIONAL, '', 1000)
+		;
+	}
+
+	protected function execute(InputInterface $input, OutputInterface $output) {
+		$all = $input->hasOption('all');
+		$chunk_size = $input->getArgument('chunk_size');
+
+		$pc = new PreviewCleanup($this->connection);
+		$count = $pc->process($all, $chunk_size, static function ($userId, $name, $action) use ($output) {
+			$output->writeln("$name - $userId: $action");
+		});
+
+		$output->writeln("$count orphaned previews deleted");
+		return 0;
+	}
+}

core/register_command.php

@@ -147,6 +147,7 @@
 	$application->add(new OC\Core\Command\Maintenance\Mode(\OC::$server->getConfig()));
 	$application->add(new OC\Core\Command\Maintenance\SingleUser(\OC::$server->getConfig()));
 	$application->add(new OC\Core\Command\Maintenance\UpdateHtaccess());
+	$application->add(new OC\Core\Command\Previews\Cleanup(\OC::$server->getDatabaseConnection()));
 
 	$application->add(new OC\Core\Command\Upgrade(\OC::$server->getConfig(), \OC::$server->getLogger(), \OC::$server->getMemCacheFactory()));
 	$application->add(

lib/base.php

@@ -668,7 +668,7 @@ public static function init() {
 		self::registerCacheHooks();
 		self::registerFilesystemHooks();
 		if ($systemConfig->getValue('enable_previews', true)) {
-			self::registerPreviewHooks();
+			OC_Hook::connect('OC_Filesystem', 'post_write', 'OC\Preview', 'post_write');
 		}
 		self::registerShareHooks();
 		self::registerLogRotate();
@@ -796,20 +796,6 @@ public static function registerFilesystemHooks() {
 		OC_Hook::connect('OC_Filesystem', 'rename', 'OC\Files\Filesystem', 'isForbiddenFileOrDir_Hook');
 	}
 
-	/**
-	 * register hooks for previews
-	 */
-	public static function registerPreviewHooks() {
-		OC_Hook::connect('OC_Filesystem', 'post_write', 'OC\Preview', 'post_write');
-		OC_Hook::connect('OC_Filesystem', 'delete', 'OC\Preview', 'prepare_delete_files');
-		OC_Hook::connect('\OCP\Versions', 'preDelete', 'OC\Preview', 'prepare_delete');
-		OC_Hook::connect('\OCP\Trashbin', 'preDelete', 'OC\Preview', 'prepare_delete');
-		OC_Hook::connect('OC_Filesystem', 'post_delete', 'OC\Preview', 'post_delete_files');
-		OC_Hook::connect('\OCP\Versions', 'delete', 'OC\Preview', 'post_delete_versions');
-		OC_Hook::connect('\OCP\Trashbin', 'delete', 'OC\Preview', 'post_delete');
-		OC_Hook::connect('\OCP\Versions', 'rollback', 'OC\Preview', 'post_delete_versions');
-	}
-
 	/**
 	 * register hooks for sharing
 	 */