owncloud/core

<?php

/**
 * @author Piotr Mrowczynski piotr@owncloud.com
 *
 * @copyright Copyright (c) 2019, 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 OCA\Files_Trashbin;

use OCP\ILogger;

class TrashExpiryManager {
    /* @var Expiration */
    private $expiration;

    /* @var Quota */
    private $quota;

    /* @var ILogger */
    private $logger;

    public function __construct(
        Expiration $expiration,
        Quota $quota,
        Ilogger $logger
    ) {
        $this->logger = $logger;
        $this->expiration = $expiration;
        $this->quota = $quota;
    }

    /**
     * Check is expiration is enabled
     *
     * @return bool
     */
    public function expiryEnabled() {
        return $this->expiration->isEnabled();
    }

    /**
     * Check if retention expiration is allowed
     *
     * @return bool
     */
    public function retentionEnabled() {
        return $this->expiration->getMaxAgeAsTimestamp() !== false;
    }

    /**
     * Expire trashbin using only retention.
     *
     * @param string $uid
     */
    public function expireTrashByRetention(string $uid) {
        // get trashbin files for this user and sort ascending by mtime
        // sorting will allow us to stop expiring early
        $userTrashbinContent = Helper::getTrashFiles('/', $uid, 'mtime', false);
        foreach ($userTrashbinContent as $key => $trashbinEntry) {
            if ($this->expiration->isExpired($trashbinEntry->getMtime())) {
                // Direct content of the trashbin's root folder will have the ".d[timestamp]" suffix
                // The deletion timestamp is in the mtime of the trashbin entry
                Trashbin::delete("{$trashbinEntry->getName()}.d{$trashbinEntry->getMtime()}", $uid);
                $this->logger->info(
                    "Remove {$trashbinEntry->getName()} from {$uid} trashbin because it exceeds max retention obligation term.",
                    ['app' => 'files_trashbin']
                );
            } else {
                break;
            }
        }
    }

    /**
     * Expire trashbin using both retention and space.
     * Retention expiry will be applied first, and if space used by user still
     * over the  quota (available space would be still negative for the user),
     * trashbin will be cleaned by space expiry.
     *
     * @param string $uid
     */
    public function expireTrash(string $uid) {
        $trashBinSize = Trashbin::getTrashbinSize($uid);
        $availableSpace = $this->quota->calculateFreeSpace($trashBinSize, $uid);

        // delete all files older then $retention_obligation
        // get trashbin files for this user and sort ascending by mtime
        // sorting will allow us to stop expiring early
        $remainingUserTrashbinContent = Helper::getTrashFiles('/', $uid, 'mtime', false);
        for ($i = 0; $i < \count($remainingUserTrashbinContent); $i++) {
            $trashbinEntry = $remainingUserTrashbinContent[$i];
            if ($this->expiration->isExpired($trashbinEntry->getMtime())) {
                // Direct content of the trashbin's root folder will have the ".d[timestamp]" suffix
                // The deletion timestamp is in the mtime of the trashbin entry
                $availableSpace += Trashbin::delete("{$trashbinEntry->getName()}.d{$trashbinEntry->getMtime()}", $uid);
                $this->logger->info(
                    "Remove {$trashbinEntry->getName()} from {$uid} trashbin because it exceeds max retention obligation term.",
                    ['app' => 'files_trashbin']
                );

                // unset the deleted file as it was already processed
                unset($remainingUserTrashbinContent[$i]);
            } else {
                break;
            }
        }

        // if space is still negative, purge remaining files
        if ($availableSpace < 0) {
            foreach ($remainingUserTrashbinContent as $trashbinEntry) {
                if ($availableSpace < 0 && $this->expiration->isExpired($trashbinEntry->getMtime(), true)) {
                    $deletedSize = Trashbin::delete("{$trashbinEntry->getName()}.d{$trashbinEntry->getMtime()}", $uid);
                    $this->logger->info(
                        "Remove {$trashbinEntry->getMtime()} ({$deletedSize}) to meet the limit of trash bin size ({$this->quota->getPurgeLimit()}% of available quota",
                        ['app' => 'files_trashbin']
                    );

                    $availableSpace += $deletedSize;
                } else {
                    break;
                }
            }
        }
    }
}