wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\Lib\Store;

use Wikibase\DataModel\Entity\EntityId;
use Wikibase\DataModel\Services\Lookup\EntityRedirectTargetLookup;

/**
 * @license GPL-2.0-or-later
 */
class RevisionBasedEntityRedirectTargetLookup implements EntityRedirectTargetLookup {

    private EntityRevisionLookup $entityRevisionLookup;

    public function __construct( EntityRevisionLookup $entityRevisionLookup ) {
        $this->entityRevisionLookup = $entityRevisionLookup;
    }

    /**
     * @inheritDoc
     */
    public function getRedirectForEntityId( EntityId $entityId, $forUpdate = '' ): ?EntityId {
        $returnNull = function () {
            return null;
        };

        $lookupMode = $forUpdate === EntityRedirectTargetLookup::FOR_UPDATE
            ? LookupConstants::LATEST_FROM_MASTER
            : LookupConstants::LATEST_FROM_REPLICA;

        return $this->entityRevisionLookup->getLatestRevisionId( $entityId, $lookupMode )
            ->onNonexistentEntity( $returnNull )
            ->onConcreteRevision( $returnNull )
            ->onRedirect( function ( $revision, EntityId $redirectTarget ) {
                return $redirectTarget;
            } )
            ->map();
    }

}