Update git submodules

[mediawiki.git] / includes / api / ApiQueryLinks.php

<?php
/**
 * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
 *
 * 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
 */

use MediaWiki\Cache\LinkBatchFactory;
use MediaWiki\Linker\LinksMigration;
use MediaWiki\ParamValidator\TypeDef\NamespaceDef;
use MediaWiki\Title\Title;
use Wikimedia\ParamValidator\ParamValidator;
use Wikimedia\ParamValidator\TypeDef\IntegerDef;

/**
 * A query module to list all wiki links on a given set of pages.
 *
 * @ingroup API
 */
class ApiQueryLinks extends ApiQueryGeneratorBase {

        private const LINKS = 'links';
        private const TEMPLATES = 'templates';

        private $table, $prefix, $titlesParam, $helpUrl;

        private LinkBatchFactory $linkBatchFactory;
        private LinksMigration $linksMigration;

        /**
         * @param ApiQuery $query
         * @param string $moduleName
         * @param LinkBatchFactory $linkBatchFactory
         * @param LinksMigration $linksMigration
         */
        public function __construct(
                ApiQuery $query,
                $moduleName,
                LinkBatchFactory $linkBatchFactory,
                LinksMigration $linksMigration
        ) {
                switch ( $moduleName ) {
                        case self::LINKS:
                                $this->table = 'pagelinks';
                                $this->prefix = 'pl';
                                $this->titlesParam = 'titles';
                                $this->helpUrl = 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Links';
                                break;
                        case self::TEMPLATES:
                                $this->table = 'templatelinks';
                                $this->prefix = 'tl';
                                $this->titlesParam = 'templates';
                                $this->helpUrl = 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Templates';
                                break;
                        default:
                                ApiBase::dieDebug( __METHOD__, 'Unknown module name' );
                }

                parent::__construct( $query, $moduleName, $this->prefix );
                $this->linkBatchFactory = $linkBatchFactory;
                $this->linksMigration = $linksMigration;
        }

        public function execute() {
                $this->run();
        }

        public function getCacheMode( $params ) {
                return 'public';
        }

        public function executeGenerator( $resultPageSet ) {
                $this->run( $resultPageSet );
        }

        /**
         * @param ApiPageSet|null $resultPageSet
         */
        private function run( $resultPageSet = null ) {
                $pages = $this->getPageSet()->getGoodPages();
                if ( $pages === [] ) {
                        return; // nothing to do
                }

                $params = $this->extractRequestParams();

                if ( isset( $this->linksMigration::$mapping[$this->table] ) ) {
                        [ $nsField, $titleField ] = $this->linksMigration->getTitleFields( $this->table );
                        $queryInfo = $this->linksMigration->getQueryInfo( $this->table );
                        $this->addTables( $queryInfo['tables'] );
                        $this->addJoinConds( $queryInfo['joins'] );
                } else {
                        $this->addTables( $this->table );
                        $nsField = $this->prefix . '_namespace';
                        $titleField = $this->prefix . '_title';
                }

                $this->addFields( [
                        'pl_from' => $this->prefix . '_from',
                        'pl_namespace' => $nsField,
                        'pl_title' => $titleField,
                ] );

                $this->addWhereFld( $this->prefix . '_from', array_keys( $pages ) );

                $multiNS = true;
                $multiTitle = true;
                if ( $params[$this->titlesParam] ) {
                        // Filter the titles in PHP so our ORDER BY bug avoidance below works right.
                        $filterNS = $params['namespace'] ? array_fill_keys( $params['namespace'], true ) : false;

                        $lb = $this->linkBatchFactory->newLinkBatch();
                        foreach ( $params[$this->titlesParam] as $t ) {
                                $title = Title::newFromText( $t );
                                if ( !$title || $title->isExternal() ) {
                                        $this->addWarning( [ 'apiwarn-invalidtitle', wfEscapeWikiText( $t ) ] );
                                } elseif ( !$filterNS || isset( $filterNS[$title->getNamespace()] ) ) {
                                        $lb->addObj( $title );
                                }
                        }
                        if ( $lb->isEmpty() ) {
                                // No titles, no results!
                                return;
                        }
                        $cond = $lb->constructSet( $this->prefix, $this->getDB() );
                        $this->addWhere( $cond );
                        $multiNS = count( $lb->data ) !== 1;
                        $multiTitle = count( array_merge( ...$lb->data ) ) !== 1;
                } elseif ( $params['namespace'] ) {
                        $this->addWhereFld( $nsField, $params['namespace'] );
                        $multiNS = $params['namespace'] === null || count( $params['namespace'] ) !== 1;
                }

                if ( $params['continue'] !== null ) {
                        $db = $this->getDB();
                        $cont = $this->parseContinueParamOrDie( $params['continue'], [ 'int', 'int', 'string' ] );
                        $op = $params['dir'] == 'descending' ? '<=' : '>=';
                        $this->addWhere( $db->buildComparison( $op, [
                                "{$this->prefix}_from" => $cont[0],
                                $nsField => $cont[1],
                                $titleField => $cont[2],
                        ] ) );
                }

                $sort = ( $params['dir'] == 'descending' ? ' DESC' : '' );
                // Here's some MySQL craziness going on: if you use WHERE foo='bar'
                // and later ORDER BY foo MySQL doesn't notice the ORDER BY is pointless
                // but instead goes and filesorts, because the index for foo was used
                // already. To work around this, we drop constant fields in the WHERE
                // clause from the ORDER BY clause
                $order = [];
                if ( count( $pages ) !== 1 ) {
                        $order[] = $this->prefix . '_from' . $sort;
                }
                if ( $multiNS ) {
                        $order[] = $nsField . $sort;
                }
                if ( $multiTitle ) {
                        $order[] = $titleField . $sort;
                }
                if ( $order ) {
                        $this->addOption( 'ORDER BY', $order );
                }
                $this->addOption( 'LIMIT', $params['limit'] + 1 );

                $res = $this->select( __METHOD__ );

                if ( $resultPageSet === null ) {
                        $this->executeGenderCacheFromResultWrapper( $res, __METHOD__, 'pl' );

                        $count = 0;
                        foreach ( $res as $row ) {
                                if ( ++$count > $params['limit'] ) {
                                        // We've reached the one extra which shows that
                                        // there are additional pages to be had. Stop here...
                                        $this->setContinueEnumParameter( 'continue',
                                                "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
                                        break;
                                }
                                $vals = [];
                                ApiQueryBase::addTitleInfo( $vals, Title::makeTitle( $row->pl_namespace, $row->pl_title ) );
                                $fit = $this->addPageSubItem( $row->pl_from, $vals );
                                if ( !$fit ) {
                                        $this->setContinueEnumParameter( 'continue',
                                                "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
                                        break;
                                }
                        }
                } else {
                        $titles = [];
                        $count = 0;
                        foreach ( $res as $row ) {
                                if ( ++$count > $params['limit'] ) {
                                        // We've reached the one extra which shows that
                                        // there are additional pages to be had. Stop here...
                                        $this->setContinueEnumParameter( 'continue',
                                                "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
                                        break;
                                }
                                $titles[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
                        }
                        $resultPageSet->populateFromTitles( $titles );
                }
        }

        public function getAllowedParams() {
                return [
                        'namespace' => [
                                ParamValidator::PARAM_TYPE => 'namespace',
                                ParamValidator::PARAM_ISMULTI => true,
                                NamespaceDef::PARAM_EXTRA_NAMESPACES => [ NS_MEDIA, NS_SPECIAL ],
                        ],
                        'limit' => [
                                ParamValidator::PARAM_DEFAULT => 10,
                                ParamValidator::PARAM_TYPE => 'limit',
                                IntegerDef::PARAM_MIN => 1,
                                IntegerDef::PARAM_MAX => ApiBase::LIMIT_BIG1,
                                IntegerDef::PARAM_MAX2 => ApiBase::LIMIT_BIG2
                        ],
                        'continue' => [
                                ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
                        ],
                        $this->titlesParam => [
                                ParamValidator::PARAM_ISMULTI => true,
                        ],
                        'dir' => [
                                ParamValidator::PARAM_DEFAULT => 'ascending',
                                ParamValidator::PARAM_TYPE => [
                                        'ascending',
                                        'descending'
                                ]
                        ],
                ];
        }

        protected function getExamplesMessages() {
                $name = $this->getModuleName();
                $path = $this->getModulePath();
                $title = Title::newMainPage()->getPrefixedText();
                $mp = rawurlencode( $title );

                return [
                        "action=query&prop={$name}&titles={$mp}"
                                => "apihelp-{$path}-example-simple",
                        "action=query&generator={$name}&titles={$mp}&prop=info"
                                => "apihelp-{$path}-example-generator",
                        "action=query&prop={$name}&titles={$mp}&{$this->prefix}namespace=2|10"
                                => "apihelp-{$path}-example-namespaces",
                ];
        }

        public function getHelpUrls() {
                return $this->helpUrl;
        }
}