wikimedia/mediawiki-core

<?php
/**
 * Updates database rows by primary key in batches.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Maintenance
 */

use MediaWiki\MediaWikiServices;
use Wikimedia\Rdbms\IDatabase;

class BatchRowWriter {
    /**
     * @var IDatabase The database to write to
     */
    protected $db;

    /**
     * @var string The name of the table to update
     */
    protected $table;

    /**
     * @var string|false A cluster name valid for use with LBFactory
     */
    protected $clusterName;

    /**
     * @var string|null For debugging which method is using this class.
     */
    protected $caller;

    /**
     * @param IDatabase $db The database to write to
     * @param string $table The name of the table to update
     * @param string|false $clusterName A cluster name valid for use with LBFactory
     */
    public function __construct( IDatabase $db, $table, $clusterName = false ) {
        $this->db = $db;
        $this->table = $table;
        $this->clusterName = $clusterName;
    }

    /**
     * Use ->setCaller( __METHOD__ ) to indicate which code is using this
     * class. Only used in debugging output.
     * @since 1.36
     *
     * @param string $caller
     * @return self
     */
    public function setCaller( $caller ) {
        $this->caller = $caller;
        return $this;
    }

    /**
     * @param array[][] $updates Array of arrays each containing two keys, 'primaryKey'
     *  and 'changes'. primaryKey must contain a map of column names to values
     *  sufficient to uniquely identify the row. changes must contain a map of column
     *  names to update values to apply to the row.
     * @phan-param array<int,array{primaryKey:array,changes:array}> $updates
     */
    public function write( array $updates ) {
        $dbProvider = MediaWikiServices::getInstance()->getConnectionProvider();
        $ticket = $dbProvider->getEmptyTransactionTicket( __METHOD__ );

        $caller = __METHOD__;
        if ( (string)$this->caller !== '' ) {
            $caller .= " (for {$this->caller})";
        }

        foreach ( $updates as $update ) {
            $this->db->newUpdateQueryBuilder()
                ->update( $this->table )
                ->set( $update['changes'] )
                ->where( $update['primaryKey'] )
                ->caller( $caller )->execute();
        }

        $dbProvider->commitAndWaitForReplication( __METHOD__, $ticket );
    }
}