diff options
Diffstat (limited to 'lib/public/AppFramework/Db/TTransactional.php')
| -rw-r--r-- | lib/public/AppFramework/Db/TTransactional.php | 61 |
1 files changed, 40 insertions, 21 deletions
diff --git a/lib/public/AppFramework/Db/TTransactional.php b/lib/public/AppFramework/Db/TTransactional.php index 1e02a129e69..8dd275e5420 100644 --- a/lib/public/AppFramework/Db/TTransactional.php +++ b/lib/public/AppFramework/Db/TTransactional.php @@ -1,33 +1,17 @@ <?php declare(strict_types=1); - -/* - * @copyright 2022 Christoph Wurst <christoph@winzerhof-wurst.at> - * - * @author 2022 Christoph Wurst <christoph@winzerhof-wurst.at> - * - * @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/>. +/** + * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors + * SPDX-License-Identifier: AGPL-3.0-or-later */ - namespace OCP\AppFramework\Db; +use OC\DB\Exceptions\DbalException; use OCP\DB\Exception; use OCP\IDBConnection; use Throwable; +use function OCP\Log\logger; /** * Helper trait for transactional operations @@ -66,4 +50,39 @@ trait TTransactional { throw $e; } } + + /** + * Wrapper around atomic() to retry after a retryable exception occurred + * + * Certain transactions might need to be retried. This is especially useful + * in highly concurrent requests where a deadlocks is thrown by the database + * without waiting for the lock to be freed (e.g. due to MySQL/MariaDB deadlock + * detection) + * + * @template T + * @param callable $fn + * @psalm-param callable():T $fn + * @param IDBConnection $db + * @param int $maxRetries + * + * @return mixed the result of the passed callable + * @psalm-return T + * + * @throws Exception for possible errors of commit or rollback or the custom operations within the closure + * @throws Throwable any other error caused by the closure + * + * @since 27.0.0 + */ + protected function atomicRetry(callable $fn, IDBConnection $db, int $maxRetries = 3): mixed { + for ($i = 0; $i < $maxRetries; $i++) { + try { + return $this->atomic($fn, $db); + } catch (DbalException $e) { + if (!$e->isRetryable() || $i === ($maxRetries - 1)) { + throw $e; + } + logger('core')->warning('Retrying operation after retryable exception.', [ 'exception' => $e ]); + } + } + } } |