wikimedia/mediawiki-core

<?php
/**
 * 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
 */

namespace MediaWiki\Specials;

use MediaWiki\Cache\LinkBatchFactory;
use MediaWiki\Html\Html;
use MediaWiki\Linker\Linker;
use MediaWiki\MainConfigNames;
use MediaWiki\SpecialPage\QueryPage;
use MediaWiki\Title\NamespaceInfo;
use MediaWiki\Title\Title;
use Skin;
use stdClass;
use Wikimedia\Rdbms\IConnectionProvider;
use Wikimedia\Rdbms\IDatabase;
use Wikimedia\Rdbms\IResultWrapper;

/**
 * List of the shortest pages in the database.
 *
 * @ingroup SpecialPage
 */
class SpecialShortPages extends QueryPage {

    private NamespaceInfo $namespaceInfo;

    /**
     * @param NamespaceInfo $namespaceInfo
     * @param IConnectionProvider $dbProvider
     * @param LinkBatchFactory $linkBatchFactory
     */
    public function __construct(
        NamespaceInfo $namespaceInfo,
        IConnectionProvider $dbProvider,
        LinkBatchFactory $linkBatchFactory
    ) {
        parent::__construct( 'Shortpages' );
        $this->namespaceInfo = $namespaceInfo;
        $this->setDatabaseProvider( $dbProvider );
        $this->setLinkBatchFactory( $linkBatchFactory );
    }

    public function isSyndicated() {
        return false;
    }

    public function getQueryInfo() {
        $config = $this->getConfig();
        $tables = [ 'page' ];
        $conds = [
            'page_namespace' => array_diff(
                $this->namespaceInfo->getContentNamespaces(),
                $config->get( MainConfigNames::ShortPagesNamespaceExclusions )
            ),
            'page_is_redirect' => 0
        ];
        $joinConds = [];
        $options = [ 'USE INDEX' => [ 'page' => 'page_redirect_namespace_len' ] ];

        // Allow extensions to modify the query
        $this->getHookRunner()->onShortPagesQuery( $tables, $conds, $joinConds, $options );

        return [
            'tables' => $tables,
            'fields' => [
                'namespace' => 'page_namespace',
                'title' => 'page_title',
                'value' => 'page_len'
            ],
            'conds' => $conds,
            'join_conds' => $joinConds,
            'options' => $options
        ];
    }

    public function reallyDoQuery( $limit, $offset = false ) {
        $fname = static::class . '::reallyDoQuery';
        $dbr = $this->getRecacheDB();
        $query = $this->getQueryInfo();
        $conds = isset( $query['conds'] ) ? (array)$query['conds'] : [];
        $namespaces = $conds['page_namespace'];
        unset( $conds['page_namespace'] );

        if ( count( $namespaces ) === 1 || !$dbr->unionSupportsOrderAndLimit() ) {
            return parent::reallyDoQuery( $limit, $offset );
        }

        // Optimization: Fix slow query on MySQL the case of multiple content namespaces,
        // by rewriting this as a UNION of separate single namespace queries (T168010).
        $sqb = $dbr->newSelectQueryBuilder()
            ->select( isset( $query['fields'] ) ? (array)$query['fields'] : [] )
            ->tables( isset( $query['tables'] ) ? (array)$query['tables'] : [] )
            ->where( $conds )
            ->options( isset( $query['options'] ) ? (array)$query['options'] : [] )
            ->joinConds( isset( $query['join_conds'] ) ? (array)$query['join_conds'] : [] );
        if ( $limit !== false ) {
            if ( $offset !== false ) {
                // We need to increase the limit by the offset rather than
                // using the offset directly, otherwise it'll skip incorrectly
                // in the subqueries.
                $sqb->limit( intval( $limit ) + intval( $offset ) );
            } else {
                $sqb->limit( intval( $limit ) );
            }
        }

        $order = $this->getOrderFields();
        if ( $this->sortDescending() ) {
            foreach ( $order as &$field ) {
                $field .= ' DESC';
            }
        }

        $uqb = $dbr->newUnionQueryBuilder()->all();
        foreach ( $namespaces as $namespace ) {
            $nsSqb = clone $sqb;
            $nsSqb->orderBy( $order );
            $nsSqb->andWhere( [ 'page_namespace' => $namespace ] );
            $uqb->add( $nsSqb );
        }

        if ( $limit !== false ) {
            $uqb->limit( intval( $limit ) );
        }
        if ( $offset !== false ) {
            $uqb->offset( intval( $offset ) );
        }
        $orderBy = 'value';
        if ( $this->sortDescending() ) {
            $orderBy .= ' DESC';
        }
        $uqb->orderBy( $orderBy );
        return $uqb->caller( $fname )->fetchResultSet();
    }

    protected function getOrderFields() {
        return [ 'page_len' ];
    }

    /**
     * @param IDatabase $db
     * @param IResultWrapper $res
     */
    public function preprocessResults( $db, $res ) {
        $this->executeLBFromResultWrapper( $res );
    }

    protected function sortDescending() {
        return false;
    }

    /**
     * @param Skin $skin
     * @param stdClass $result Result row
     * @return string
     */
    public function formatResult( $skin, $result ) {
        $dm = $this->getLanguage()->getDirMark();

        $title = Title::makeTitleSafe( $result->namespace, $result->title );
        if ( !$title ) {
            return Html::element( 'span', [ 'class' => 'mw-invalidtitle' ],
                Linker::getInvalidTitleDescription( $this->getContext(), $result->namespace, $result->title ) );
        }

        $linkRenderer = $this->getLinkRenderer();
        $hlink = $linkRenderer->makeKnownLink(
            $title,
            $this->msg( 'hist' )->text(),
            [],
            [ 'action' => 'history' ]
        );
        $hlinkInParentheses = $this->msg( 'parentheses' )->rawParams( $hlink )->escaped();

        if ( $this->isCached() ) {
            $plink = $linkRenderer->makeLink( $title );
            $exists = $title->exists();
        } else {
            $plink = $linkRenderer->makeKnownLink( $title );
            $exists = true;
        }

        $size = $this->msg( 'nbytes' )->numParams( $result->value )->escaped();

        return $exists
            ? "{$hlinkInParentheses} {$dm}{$plink} {$dm}[{$size}]"
            : "<del>{$hlinkInParentheses} {$dm}{$plink} {$dm}[{$size}]</del>";
    }

    protected function getGroupName() {
        return 'maintenance';
    }
}

/**
 * Retain the old class name for backwards compatibility.
 * @deprecated since 1.41
 */
class_alias( SpecialShortPages::class, 'SpecialShortPages' );