Set Redis::OPT_READ_TIMEOUT by default

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

<?php
/**
 * API module to return redirects to a page
 *
 * Created on Dec 30, 2013
 *
 * Copyright © 2013 Brad Jorsch <bjorsch@wikimedia.org>
 *
 * 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
 * @since 1.23
 */

/**
 * This query lists redirects to the given pages.
 *
 * @ingroup API
 */
class ApiQueryRedirects extends ApiQueryGeneratorBase {

        public function __construct( $query, $moduleName ) {
                parent::__construct( $query, $moduleName, 'rd' );
        }

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

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

        /**
         * @param ApiPageSet $resultPageSet
         */
        private function run( ApiPageSet $resultPageSet = null ) {
                $db = $this->getDB();
                $params = $this->extractRequestParams();
                $emptyString = $db->addQuotes( '' );

                $pageSet = $this->getPageSet();
                $titles = $pageSet->getGoodTitles() + $pageSet->getMissingTitles();

                if ( !is_null( $params['continue'] ) ) {
                        $cont = explode( '|', $params['continue'] );
                        $this->dieContinueUsageIf( count( $cont ) != 3 );
                        $rd_namespace = (int)$cont[0];
                        $this->dieContinueUsageIf( $rd_namespace != $cont[0] );
                        $rd_title = $db->addQuotes( $cont[1] );
                        $rd_from = (int)$cont[2];
                        $this->dieContinueUsageIf( $rd_from != $cont[2] );
                        $this->addWhere(
                                "rd_namespace > $rd_namespace OR " .
                                "(rd_namespace = $rd_namespace AND " .
                                "(rd_title > $rd_title OR " .
                                "(rd_title = $rd_title AND " .
                                "rd_from >= $rd_from)))"
                        );

                        // Remove titles that we're past already
                        $titles = array_filter( $titles, function ( $t ) use ( $rd_namespace, $rd_title ) {
                                $ns = $t->getNamespace();
                                return ( $ns > $rd_namespace ||
                                        $ns == $rd_namespace && $t->getDBKey() >= $rd_title
                                );
                        } );
                }

                if ( !$titles ) {
                        return; // nothing to do
                }

                $this->addTables( array( 'redirect', 'page' ) );
                $this->addFields( array(
                        'rd_from',
                        'rd_namespace',
                        'rd_title',
                ) );

                if ( is_null( $resultPageSet ) ) {
                        $prop = array_flip( $params['prop'] );
                        $fld_pageid = isset( $prop['pageid'] );
                        $fld_title = isset( $prop['title'] );
                        $fld_fragment = isset( $prop['fragment'] );

                        $this->addFieldsIf( 'rd_fragment', $fld_fragment );
                        $this->addFieldsIf( array( 'page_namespace', 'page_title' ), $fld_title );
                } else {
                        $this->addFields( array( 'page_namespace', 'page_title' ) );
                }

                $lb = new LinkBatch( $titles );
                $this->addWhere( array(
                        'rd_from = page_id',
                        "rd_interwiki = $emptyString OR rd_interwiki IS NULL",
                        $lb->constructSet( 'rd', $db ),
                ) );

                if ( $params['show'] !== null ) {
                        $show = array_flip( $params['show'] );
                        if ( isset( $show['fragment'] ) && isset( $show['!fragment'] ) ) {
                                $this->dieUsageMsg( 'show' );
                        }
                        $this->addWhereIf( "rd_fragment != $emptyString", isset( $show['fragment'] ) );
                        $this->addWhereIf(
                                "rd_fragment = $emptyString OR rd_fragment IS NULL",
                                isset( $show['!fragment'] )
                        );
                }

                $map = $pageSet->getAllTitlesByNamespace();

                // Why, MySQL? Why do you do this to us?
                $sortby = array();
                if ( count( $map ) > 1 ) {
                        $sortby[] = 'rd_namespace';
                }
                $theTitle = null;
                foreach ( $map as $nsTitles ) {
                        reset( $nsTitles );
                        $key = key( $nsTitles );
                        if ( $theTitle === null ) {
                                $theTitle = $key;
                        }
                        if ( count( $nsTitles ) > 1 || $key !== $theTitle ) {
                                $sortby[] = 'rd_title';
                                break;
                        }
                }
                $sortby[] = 'rd_from';
                $this->addOption( 'ORDER BY', $sortby );

                $this->addOption( 'LIMIT', $params['limit'] + 1 );

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

                if ( is_null( $resultPageSet ) ) {
                        $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->rd_namespace|$row->rd_title|$row->rd_from"
                                        );
                                        break;
                                }

                                # Get the ID of the current page
                                $id = $map[$row->rd_namespace][$row->rd_title];

                                $vals = array();
                                if ( $fld_pageid ) {
                                        $vals['pageid'] = $row->rd_from;
                                }
                                if ( $fld_title ) {
                                        ApiQueryBase::addTitleInfo( $vals,
                                                Title::makeTitle( $row->page_namespace, $row->page_title )
                                        );
                                }
                                if ( $fld_fragment && $row->rd_fragment !== null && $row->rd_fragment !== '' ) {
                                        $vals['fragment'] = $row->rd_fragment;
                                }
                                $fit = $this->addPageSubItem( $id, $vals );
                                if ( !$fit ) {
                                        $this->setContinueEnumParameter( 'continue',
                                                "$row->rd_namespace|$row->rd_title|$row->rd_from"
                                        );
                                        break;
                                }
                        }
                } else {
                        $titles = array();
                        $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->rd_namespace|$row->rd_title|$row->rd_from"
                                        );
                                        break;
                                }
                                $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
                        }
                        $resultPageSet->populateFromTitles( $titles );
                }
        }

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

        public function getAllowedParams() {
                return array(
                        'prop' => array(
                                ApiBase::PARAM_TYPE => array(
                                        'pageid',
                                        'title',
                                        'fragment',
                                ),
                                ApiBase::PARAM_ISMULTI => true,
                                ApiBase::PARAM_DFLT => 'pageid|title',
                        ),
                        'show' => array(
                                ApiBase::PARAM_TYPE => array(
                                        'fragment', '!fragment',
                                ),
                                ApiBase::PARAM_ISMULTI => true,
                        ),
                        'limit' => array(
                                ApiBase::PARAM_DFLT => 10,
                                ApiBase::PARAM_TYPE => 'limit',
                                ApiBase::PARAM_MIN => 1,
                                ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
                                ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
                        ),
                        'continue' => null,
                );
        }

        public function getParamDescription() {
                return array(
                        'prop' => array(
                                'Which properties to get:',
                                ' pageid   - Page id of each redirect',
                                ' title    - Title of each redirect',
                                ' fragment - Fragment of each redirect, if any',
                        ),
                        'show' => array(
                                'Show only items that meet this criteria.',
                                ' fragment  - Only show redirects with a fragment',
                                ' !fragment - Only show redirects without a fragment',
                        ),
                        'limit' => 'How many redirects to return',
                        'continue' => 'When more results are available, use this to continue',
                );
        }

        public function getDescription() {
                return 'Returns all redirects to the given page(s).';
        }

        public function getExamples() {
                return array(
                        'api.php?action=query&prop=redirects&titles=Main%20Page'
                                => 'Get a list of redirects to the [[Main Page]]',
                        'api.php?action=query&generator=redirects&titles=Main%20Page&prop=info'
                                => 'Get information about all redirects to the [[Main Page]]',
                );
        }

        public function getHelpUrls() {
                return 'https://www.mediawiki.org/wiki/API:Properties#redirects_.2F_rd';
        }
}