wikimedia/mediawiki-core

<?php
/**
 * Generic class to cleanup a database table.
 *
 * 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\WikiMap\WikiMap;

// @codeCoverageIgnoreStart
require_once __DIR__ . '/Maintenance.php';
// @codeCoverageIgnoreEnd

/**
 * Generic class to cleanup a database table. Already subclasses Maintenance.
 *
 * @ingroup Maintenance
 */
class TableCleanup extends Maintenance {
    /** @var array */
    protected $defaultParams = [
        'table' => 'page',
        'conds' => [],
        'index' => 'page_id',
        'callback' => 'processRow',
    ];

    /** @var bool */
    protected $dryrun = false;
    /** @var int */
    protected $reportInterval = 100;

    protected int $processed;
    protected int $updated;
    protected int $count;
    protected float $startTime;
    protected string $table;

    public function __construct() {
        parent::__construct();
        $this->addOption( 'dry-run', 'Perform a dry run' );
        $this->addOption( 'reporting-interval', 'How often to print status line' );
        $this->setBatchSize( 100 );
    }

    public function execute() {
        $this->reportInterval = $this->getOption( 'reporting-interval', $this->reportInterval );

        $this->dryrun = $this->hasOption( 'dry-run' );

        if ( $this->dryrun ) {
            $this->output( "Checking for bad titles...\n" );
        } else {
            $this->output( "Checking and fixing bad titles...\n" );
        }

        $this->runTable( $this->defaultParams );
    }

    protected function init( $count, $table ) {
        $this->processed = 0;
        $this->updated = 0;
        $this->count = $count;
        $this->startTime = microtime( true );
        $this->table = $table;
    }

    /**
     * @param int $updated
     */
    protected function progress( $updated ) {
        $this->updated += $updated;
        $this->processed++;
        if ( $this->processed % $this->reportInterval != 0 ) {
            return;
        }
        $portion = $this->processed / $this->count;
        $updateRate = $this->updated / $this->processed;

        $now = microtime( true );
        $delta = $now - $this->startTime;
        $estimatedTotalTime = $delta / $portion;
        $eta = $this->startTime + $estimatedTotalTime;

        $this->output(
            sprintf( "%s %s: %6.2f%% done on %s; ETA %s [%d/%d] %.2f/sec <%.2f%% updated>\n",
                WikiMap::getCurrentWikiDbDomain()->getId(),
                wfTimestamp( TS_DB, intval( $now ) ),
                $portion * 100.0,
                $this->table,
                wfTimestamp( TS_DB, intval( $eta ) ),
                $this->processed,
                $this->count,
                $this->processed / $delta,
                $updateRate * 100.0
            )
        );
        flush();
    }

    /**
     * @param array $params
     */
    public function runTable( $params ) {
        $dbr = $this->getReplicaDB();

        if ( array_diff( array_keys( $params ),
            [ 'table', 'conds', 'index', 'callback' ] )
        ) {
            $this->fatalError( __METHOD__ . ': Missing parameter ' . implode( ', ', $params ) );
        }

        $table = $params['table'];
        // count(*) would melt the DB for huge tables, we can estimate here
        $count = $dbr->newSelectQueryBuilder()
            ->table( $table )
            ->caller( __METHOD__ )
            ->estimateRowCount();
        $this->init( $count, $table );
        $this->output( "Processing $table...\n" );

        $index = (array)$params['index'];
        $indexConds = [];
        $callback = [ $this, $params['callback'] ];

        while ( true ) {
            $conds = array_merge( $params['conds'], $indexConds );
            $res = $dbr->newSelectQueryBuilder()
                ->select( '*' )
                ->from( $table )
                ->where( $conds )
                ->orderBy( implode( ',', $index ) )
                ->limit( $this->getBatchSize() )
                ->caller( __METHOD__ )->fetchResultSet();
            if ( !$res->numRows() ) {
                // Done
                break;
            }

            foreach ( $res as $row ) {
                call_user_func( $callback, $row );
            }

            if ( $res->numRows() < $this->getBatchSize() ) {
                // Done
                break;
            }

            // Update the conditions to select the next batch.
            $conds = [];
            foreach ( $index as $field ) {
                // @phan-suppress-next-line PhanPossiblyUndeclaredVariable $res has at at least one item
                $conds[ $field ] = $row->$field;
            }
            $indexConds = [ $dbr->buildComparison( '>', $conds ) ];
        }

        $this->output( "Finished $table... $this->updated of $this->processed rows updated\n" );
    }

    /**
     * @param string[] $matches
     * @return string
     */
    protected function hexChar( $matches ) {
        return sprintf( "\\x%02x", ord( $matches[1] ) );
    }
}