wikimedia/mediawiki-extensions-Wikibase

<?php

declare( strict_types = 1 );
namespace Wikibase\Repo\Maintenance;

use MediaWiki\Maintenance\Maintenance;
use Wikibase\DataModel\Entity\Item;
use Wikibase\Lib\Rdbms\RepoDomainDb;
use Wikibase\Lib\WikibaseSettings;
use Wikibase\Repo\WikibaseRepo;
use Wikimedia\Rdbms\IDatabase;
use Wikimedia\Rdbms\IReadableDatabase;

$basePath = getenv( 'MW_INSTALL_PATH' ) !== false ? getenv( 'MW_INSTALL_PATH' ) : __DIR__ . '/../../../..';

require_once $basePath . '/maintenance/Maintenance.php';

/**
 * Maintenance script for pruning rows belonging to deleted or redirected items
 * from the wb_items_per_site table.
 *
 * @license GPL-2.0-or-later
 * @author Marius Hoch < hoo@online.de >
 */
class PruneItemsPerSite extends Maintenance {

    public function __construct() {
        parent::__construct();

        $this->addDescription( 'Pune rows belonging to deleted or redirected Items from the wb_items_per_site table' );

        $this->addOption( 'select-batch-size', "Number of table rows to scan per select (100000 by default)", false, true );
    }

    /**
     * @inheritDoc
     */
    public function execute() {
        if ( !WikibaseSettings::isRepoEnabled() ) {
            $this->fatalError( "You need to have Wikibase enabled in order to use this maintenance script!\n\n" );
        }

        if ( !in_array( Item::ENTITY_TYPE, WikibaseRepo::getLocalEntitySource()->getEntityTypes() ) ) {
            $this->fatalError(
                "This script assumes Items to be part of the local entity source."
            );
        }

        $itemNamespace = WikibaseRepo::getEntityNamespaceLookup()->getEntityNamespace( Item::ENTITY_TYPE );

        $db = WikibaseRepo::getRepoDomainDbFactory()->newRepoDb();
        $selectBatchSize = (int)$this->getOption( 'select-batch-size', 100000 );

        $this->prune( $db, $itemNamespace, $selectBatchSize );
    }

    private function prune(
        RepoDomainDb $db,
        int $itemNamespace,
        int $selectBatchSize
    ) {
        $dbr = $db->connections()->getReadConnection( [ 'vslow' ] );
        $dbw = $db->connections()->getWriteConnection();

        $maxIpsRowId = (int)$dbr->newSelectQueryBuilder()
            ->select( 'MAX(ips_row_id)' )
            ->from( 'wb_items_per_site' )
            ->caller( __METHOD__ )->fetchField();
        // Add 1%, but at least 50, to the maxIpsRowId to use, for items created during the script run
        $maxIpsRowId = max( $maxIpsRowId * 1.01, $maxIpsRowId + 50 );

        $startRowId = (int)$dbr->newSelectQueryBuilder()
            ->select( 'MIN(ips_row_id)' )
            ->from( 'wb_items_per_site' )
            ->caller( __METHOD__ )->fetchField();
        while ( $startRowId < $maxIpsRowId ) {
            $endRowId = $startRowId + $selectBatchSize;
            $rowsToDelete = $this->selectInRange( $dbr, $itemNamespace, $startRowId, $endRowId );
            $this->output( "Read up to ips_row_id $endRowId.\n" );

            if ( $rowsToDelete ) {
                $affectedRows = $this->deleteRows( $dbw, $rowsToDelete );
                $this->output( "Deleted $affectedRows rows.\n" );
                $db->replication()->wait();
                $db->autoReconfigure();
            }

            $startRowId = $endRowId;
        }
    }

    private function selectInRange( IReadableDatabase $dbr, int $itemNamespace, int $startRowId, int $endRowId ): array {
        return $dbr->newSelectQueryBuilder()
            ->select( 'ips_row_id' )
            ->from( 'wb_items_per_site' )
            ->leftJoin( 'page', null, [
                'page_title = ' . $dbr->buildConcat( [
                    $dbr->addQuotes( 'Q' ),
                    'ips_item_id',
                ] ),
                'page_namespace' => $itemNamespace,
                'page_is_redirect' => 0,
            ] )
            ->where( [
                $dbr->expr( 'ips_row_id', '>=', $startRowId ),
                $dbr->expr( 'ips_row_id', '<', $endRowId ),
                'page_id' => null,
            ] )
            ->caller( __METHOD__ )->fetchFieldValues();
    }

    private function deleteRows( IDatabase $dbw, array $rowsToDelete ): int {
        $dbw->newDeleteQueryBuilder()
            ->deleteFrom( 'wb_items_per_site' )
            ->where( [
                'ips_row_id' => $rowsToDelete,
            ] )
            ->caller( __METHOD__ )
            ->execute();

        return $dbw->affectedRows();
    }

}

$maintClass = PruneItemsPerSite::class;
require_once RUN_MAINTENANCE_IF_MAIN;