includes/api/ApiQueryRedirects.php

   1 <?php
   2 /**
   3  * API module to return redirects to a page
   4  *
   5  * Created on Dec 30, 2013
   6  *
   7  * Copyright © 2013 Brad Jorsch <bjorsch@wikimedia.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  * http://www.gnu.org/copyleft/gpl.html
  23  *
  24  * @file
  25  * @since 1.23
  26  */
  27
  28 /**
  29  * This query lists redirects to the given pages.
  30  *
  31  * @ingroup API
  32  */
  33 class ApiQueryRedirects extends ApiQueryGeneratorBase {
  34
  35         public function __construct( ApiQuery $query, $moduleName ) {
  36                 parent::__construct( $query, $moduleName, 'rd' );
  37         }
  38
  39         public function execute() {
  40                 $this->run();
  41         }
  42
  43         public function executeGenerator( $resultPageSet ) {
  44                 $this->run( $resultPageSet );
  45         }
  46
  47         /**
  48          * @param ApiPageSet $resultPageSet
  49          */
  50         private function run( ApiPageSet $resultPageSet = null ) {
  51                 $db = $this->getDB();
  52                 $params = $this->extractRequestParams();
  53                 $emptyString = $db->addQuotes( '' );
  54
  55                 $pageSet = $this->getPageSet();
  56                 $titles = $pageSet->getGoodTitles() + $pageSet->getMissingTitles();
  57
  58                 if ( !is_null( $params['continue'] ) ) {
  59                         $cont = explode( '|', $params['continue'] );
  60                         $this->dieContinueUsageIf( count( $cont ) != 3 );
  61                         $rd_namespace = (int)$cont[0];
  62                         $this->dieContinueUsageIf( $rd_namespace != $cont[0] );
  63                         $rd_title = $db->addQuotes( $cont[1] );
  64                         $rd_from = (int)$cont[2];
  65                         $this->dieContinueUsageIf( $rd_from != $cont[2] );
  66                         $this->addWhere(
  67                                 "rd_namespace > $rd_namespace OR " .
  68                                 "(rd_namespace = $rd_namespace AND " .
  69                                 "(rd_title > $rd_title OR " .
  70                                 "(rd_title = $rd_title AND " .
  71                                 "rd_from >= $rd_from)))"
  72                         );
  73
  74                         // Remove titles that we're past already
  75                         $titles = array_filter( $titles, function ( $t ) use ( $rd_namespace, $rd_title ) {
  76                                 $ns = $t->getNamespace();
  77                                 return ( $ns > $rd_namespace ||
  78                                         $ns == $rd_namespace && $t->getDBKey() >= $rd_title
  79                                 );
  80                         } );
  81                 }
  82
  83                 if ( !$titles ) {
  84                         return; // nothing to do
  85                 }
  86
  87                 $this->addTables( array( 'redirect', 'page' ) );
  88                 $this->addFields( array(
  89                         'rd_from',
  90                         'rd_namespace',
  91                         'rd_title',
  92                 ) );
  93
  94                 if ( is_null( $resultPageSet ) ) {
  95                         $prop = array_flip( $params['prop'] );
  96                         $fld_pageid = isset( $prop['pageid'] );
  97                         $fld_title = isset( $prop['title'] );
  98                         $fld_fragment = isset( $prop['fragment'] );
  99
 100                         $this->addFieldsIf( 'rd_fragment', $fld_fragment );
 101                         $this->addFieldsIf( array( 'page_namespace', 'page_title' ), $fld_title );
 102                 } else {
 103                         $this->addFields( array( 'page_namespace', 'page_title' ) );
 104                 }
 105
 106                 $lb = new LinkBatch( $titles );
 107                 $this->addWhere( array(
 108                         'rd_from = page_id',
 109                         "rd_interwiki = $emptyString OR rd_interwiki IS NULL",
 110                         $lb->constructSet( 'rd', $db ),
 111                 ) );
 112
 113                 if ( $params['show'] !== null ) {
 114                         $show = array_flip( $params['show'] );
 115                         if ( isset( $show['fragment'] ) && isset( $show['!fragment'] ) ) {
 116                                 $this->dieUsageMsg( 'show' );
 117                         }
 118                         $this->addWhereIf( "rd_fragment != $emptyString", isset( $show['fragment'] ) );
 119                         $this->addWhereIf(
 120                                 "rd_fragment = $emptyString OR rd_fragment IS NULL",
 121                                 isset( $show['!fragment'] )
 122                         );
 123                 }
 124
 125                 $map = $pageSet->getAllTitlesByNamespace();
 126
 127                 // Why, MySQL? Why do you do this to us?
 128                 $sortby = array();
 129                 if ( count( $map ) > 1 ) {
 130                         $sortby[] = 'rd_namespace';
 131                 }
 132                 $theTitle = null;
 133                 foreach ( $map as $nsTitles ) {
 134                         reset( $nsTitles );
 135                         $key = key( $nsTitles );
 136                         if ( $theTitle === null ) {
 137                                 $theTitle = $key;
 138                         }
 139                         if ( count( $nsTitles ) > 1 || $key !== $theTitle ) {
 140                                 $sortby[] = 'rd_title';
 141                                 break;
 142                         }
 143                 }
 144                 $sortby[] = 'rd_from';
 145                 $this->addOption( 'ORDER BY', $sortby );
 146
 147                 $this->addOption( 'LIMIT', $params['limit'] + 1 );
 148
 149                 $res = $this->select( __METHOD__ );
 150
 151                 if ( is_null( $resultPageSet ) ) {
 152                         $count = 0;
 153                         foreach ( $res as $row ) {
 154                                 if ( ++$count > $params['limit'] ) {
 155                                         // We've reached the one extra which shows that
 156                                         // there are additional pages to be had. Stop here...
 157                                         $this->setContinueEnumParameter( 'continue',
 158                                                 "$row->rd_namespace|$row->rd_title|$row->rd_from"
 159                                         );
 160                                         break;
 161                                 }
 162
 163                                 # Get the ID of the current page
 164                                 $id = $map[$row->rd_namespace][$row->rd_title];
 165
 166                                 $vals = array();
 167                                 if ( $fld_pageid ) {
 168                                         $vals['pageid'] = $row->rd_from;
 169                                 }
 170                                 if ( $fld_title ) {
 171                                         ApiQueryBase::addTitleInfo( $vals,
 172                                                 Title::makeTitle( $row->page_namespace, $row->page_title )
 173                                         );
 174                                 }
 175                                 if ( $fld_fragment && $row->rd_fragment !== null && $row->rd_fragment !== '' ) {
 176                                         $vals['fragment'] = $row->rd_fragment;
 177                                 }
 178                                 $fit = $this->addPageSubItem( $id, $vals );
 179                                 if ( !$fit ) {
 180                                         $this->setContinueEnumParameter( 'continue',
 181                                                 "$row->rd_namespace|$row->rd_title|$row->rd_from"
 182                                         );
 183                                         break;
 184                                 }
 185                         }
 186                 } else {
 187                         $titles = array();
 188                         $count = 0;
 189                         foreach ( $res as $row ) {
 190                                 if ( ++$count > $params['limit'] ) {
 191                                         // We've reached the one extra which shows that
 192                                         // there are additional pages to be had. Stop here...
 193                                         $this->setContinueEnumParameter( 'continue',
 194                                                 "$row->rd_namespace|$row->rd_title|$row->rd_from"
 195                                         );
 196                                         break;
 197                                 }
 198                                 $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 199                         }
 200                         $resultPageSet->populateFromTitles( $titles );
 201                 }
 202         }
 203
 204         public function getCacheMode( $params ) {
 205                 return 'public';
 206         }
 207
 208         public function getAllowedParams() {
 209                 return array(
 210                         'prop' => array(
 211                                 ApiBase::PARAM_TYPE => array(
 212                                         'pageid',
 213                                         'title',
 214                                         'fragment',
 215                                 ),
 216                                 ApiBase::PARAM_ISMULTI => true,
 217                                 ApiBase::PARAM_DFLT => 'pageid|title',
 218                         ),
 219                         'show' => array(
 220                                 ApiBase::PARAM_TYPE => array(
 221                                         'fragment', '!fragment',
 222                                 ),
 223                                 ApiBase::PARAM_ISMULTI => true,
 224                         ),
 225                         'limit' => array(
 226                                 ApiBase::PARAM_DFLT => 10,
 227                                 ApiBase::PARAM_TYPE => 'limit',
 228                                 ApiBase::PARAM_MIN => 1,
 229                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 230                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 231                         ),
 232                         'continue' => null,
 233                 );
 234         }
 235
 236         public function getParamDescription() {
 237                 return array(
 238                         'prop' => array(
 239                                 'Which properties to get:',
 240                                 ' pageid   - Page id of each redirect',
 241                                 ' title    - Title of each redirect',
 242                                 ' fragment - Fragment of each redirect, if any',
 243                         ),
 244                         'show' => array(
 245                                 'Show only items that meet this criteria.',
 246                                 ' fragment  - Only show redirects with a fragment',
 247                                 ' !fragment - Only show redirects without a fragment',
 248                         ),
 249                         'limit' => 'How many redirects to return',
 250                         'continue' => 'When more results are available, use this to continue',
 251                 );
 252         }
 253
 254         public function getDescription() {
 255                 return 'Returns all redirects to the given page(s).';
 256         }
 257
 258         public function getExamples() {
 259                 return array(
 260                         'api.php?action=query&prop=redirects&titles=Main%20Page'
 261                                 => 'Get a list of redirects to the [[Main Page]]',
 262                         'api.php?action=query&generator=redirects&titles=Main%20Page&prop=info'
 263                                 => 'Get information about all redirects to the [[Main Page]]',
 264                 );
 265         }
 266
 267         public function getHelpUrls() {
 268                 return 'https://www.mediawiki.org/wiki/API:Properties#redirects_.2F_rd';
 269         }
 270 }