wikimedia/mediawiki-core

<?php
/**
 * Resets the page_random field for articles in the provided time range.
 *
 * 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
 */

require_once __DIR__ . '/Maintenance.php';

/**
 * Maintenance script that resets page_random over a time range.
 *
 * @ingroup Maintenance
 */
class ResetPageRandom extends Maintenance {
    public function __construct() {
        parent::__construct();
        $this->addDescription( 'Reset the page_random for articles within given date range' );
        $this->addOption( 'from',
            'From date range selector to select articles to update, ex: 20041011000000', false, true );
        $this->addOption( 'to',
            'To date range selector to select articles to update, ex: 20050708000000', false, true );
        $this->addOption( 'dry', 'Do not update column' );
        $this->addOption( 'batch-start',
            'Optional: Use when you need to restart the reset process from a given page ID offset'
            . ' in case a previous reset failed or was stopped'
        );
        // Initialize batch size to a good default value and enable the batch size option.
        $this->setBatchSize( 200 );
    }

    public function execute() {
        $batchSize = $this->getBatchSize();
        $dbw = $this->getPrimaryDB();
        $dbr = $this->getReplicaDB();
        $from = wfTimestampOrNull( TS_MW, $this->getOption( 'from' ) );
        $to = wfTimestampOrNull( TS_MW, $this->getOption( 'to' ) );

        if ( $from === null || $to === null ) {
            $this->output( "--from and --to have to be provided" . PHP_EOL );
            return false;
        }
        if ( $from >= $to ) {
            $this->output( "--from has to be smaller than --to" . PHP_EOL );
            return false;
        }
        $batchStart = (int)$this->getOption( 'batch-start', 0 );
        $changed = 0;
        $dry = (bool)$this->getOption( 'dry' );

        $message = "Resetting page_random column within date range from $from to $to";
        if ( $batchStart > 0 ) {
            $message .= " starting from page ID $batchStart";
        }
        $message .= $dry ? ". dry run" : '.';

        $this->output( $message . PHP_EOL );
        do {
            $this->output( "  ...doing chunk of $batchSize from $batchStart " . PHP_EOL );

            // Find the oldest page revision associated with each page_id. Iff it falls in the given
            // time range AND it's greater than $batchStart, yield the page ID. If it falls outside the
            // time range, it was created before or after the occurrence of T208909 and its page_random
            // is considered valid. The replica is used for this read since page_id and the rev_timestamp
            // will not change between queries.
            $queryBuilder = $dbr->newSelectQueryBuilder()
                ->select( 'page_id' )
                ->from( 'page' )
                ->where( $dbr->expr( 'page_id', '>', $batchStart ) )
                ->limit( $batchSize )
                ->orderBy( 'page_id' );
            $subquery = $queryBuilder->newSubquery()
                ->select( 'MIN(rev_timestamp)' )
                ->from( 'revision' )
                ->where( 'rev_page=page_id' );
            $queryBuilder->andWhere(
                '(' . $subquery->getSQL() . ') BETWEEN ' .
                $dbr->addQuotes( $dbr->timestamp( $from ) ) . ' AND ' . $dbr->addQuotes( $dbr->timestamp( $to ) )
            );

            $res = $queryBuilder->caller( __METHOD__ )->fetchResultSet();
            $row = null;
            foreach ( $res as $row ) {
                if ( !$dry ) {
                    # Update the row...
                    $dbw->newUpdateQueryBuilder()
                        ->update( 'page' )
                        ->set( [ 'page_random' => wfRandom() ] )
                        ->where( [ 'page_id' => $row->page_id ] )
                        ->caller( __METHOD__ )
                        ->execute();
                    $changed += $dbw->affectedRows();
                } else {
                    $changed++;
                }
            }
            if ( $row ) {
                $batchStart = $row->page_id;
            } else {
                // We don't need to set the $batchStart as $res is empty,
                // and we don't need to do another loop
                // the while() condition will evaluate to false and
                // we will leave the do{}while() block.
            }

            $this->waitForReplication();
        } while ( $res->numRows() === $batchSize );
        $this->output( "page_random reset complete ... changed $changed rows" . PHP_EOL );

        return true;
    }
}

$maintClass = ResetPageRandom::class;
require_once RUN_MAINTENANCE_IF_MAIN;