owncloud/core

<?php
/**
 * @author Viktar Dubiniuk <dubiniuk@owncloud.com>
 *
 * @copyright Copyright (c) 2018, 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\DAV\Migrations;

use OCP\DB\QueryBuilder\IQueryBuilder;
use OCP\Files\Node;
use OCP\IDBConnection;
use OCP\IUser;
use OCP\IUserManager;
use OCP\Migration\ISqlMigration;

/*
 * Resolve userid/propertypath into fileid
 * Update all entries with actual fileid if possible
 * Drop all entries that can't be resolved
 */
class Version20170202213905 implements ISqlMigration {
    /** @var IUserManager */
    private $userManager;

    /** @var string[]  */
    private $statements = [];

    public function __construct(IUserManager $userManager) {
        $this->userManager = $userManager;
    }

    /**
     * @param IDBConnection $connection
     * @return array
     */
    public function sql(IDBConnection $connection) {
        $qb = $connection->getQueryBuilder();
        $qb->select('*')
            ->from('properties', 'props')
            ->setMaxResults(1);
        $result = $qb->execute();
        $row = $result->fetch();

        // There is nothing to do if table is empty or has no userid field
        if (!$row || !isset($row['userid'])) {
            return $this->statements;
        }

        $qb->resetQueryParts()
            ->setMaxResults(null)
            ->select('userid', 'propertypath')
            ->from('properties', 'props')
            ->groupBy('userid')
            ->addGroupBy('propertypath')
            ->orderBy('userid')
            ->addOrderBy('propertypath');

        $selectResult = $qb->execute();
        while ($row = $selectResult->fetch()) {
            try {
                $sql = $this->getRepairEntrySql($qb, $row);
                if ($sql !== null) {
                    $this->statements[] = $sql;
                }
            } catch (\Exception $e) {
            }
        }

        //Mounted FS can have side effects on further migrations
        \OC_Util::tearDownFS();

        // drop entries with empty fileid
        $dropQuery = $qb->resetQueryParts()
            ->delete('properties')
            ->where(
                $qb->expr()->eq('fileid', $qb->expr()->literal('0'))
            )
            ->orWhere(
                $qb->expr()->isNull('fileid')
            );
        $this->statements[] = $dropQuery->getSQL();

        return $this->statements;
    }

    /**
     * @param IQueryBuilder $qb
     * @param $entry
     * @return string|null
     */
    private function getRepairEntrySql(IQueryBuilder $qb, $entry) {
        $userId = $entry['userid'];
        $user = $this->userManager->get($userId);
        if (!($user instanceof IUser)) {
            return null;
        }

        $node = \OC::$server->getUserFolder($userId)->get($entry['propertypath']);
        if ($node instanceof Node && $node->getId()) {
            $fileId = $node->getId();
            $updateQuery = $this->getRepairQuery($qb, $fileId, $userId, $entry['propertypath']);
            return $updateQuery->getSQL();
        }
        return null;
    }

    /**
     * @param IQueryBuilder $qb
     * @param int $fileId
     * @param string $userId
     * @param string $propertyPath
     * @return IQueryBuilder
     */
    private function getRepairQuery(IQueryBuilder $qb, $fileId, $userId, $propertyPath) {
        return $qb->resetQueryParts()
            ->update('properties')
            ->set(
                'fileid',
                $qb->expr()->literal($fileId)
            )
            ->where(
                $qb->expr()->eq('userid', $qb->expr()->literal($userId))
            )
            ->andWhere(
                $qb->expr()->eq(
                    'propertypath',
                    $qb->expr()->literal($propertyPath)
                )
            );
    }
}