includes/api/ApiQueryLinks.php

   1 <?php
   2 /**
   3  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * A query module to list all wiki links on a given set of pages.
  25  *
  26  * @ingroup API
  27  */
  28 class ApiQueryLinks extends ApiQueryGeneratorBase {
  29
  30         const LINKS = 'links';
  31         const TEMPLATES = 'templates';
  32
  33         private $table, $prefix, $titlesParam, $helpUrl;
  34
  35         public function __construct( ApiQuery $query, $moduleName ) {
  36                 switch ( $moduleName ) {
  37                         case self::LINKS:
  38                                 $this->table = 'pagelinks';
  39                                 $this->prefix = 'pl';
  40                                 $this->titlesParam = 'titles';
  41                                 $this->helpUrl = 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Links';
  42                                 break;
  43                         case self::TEMPLATES:
  44                                 $this->table = 'templatelinks';
  45                                 $this->prefix = 'tl';
  46                                 $this->titlesParam = 'templates';
  47                                 $this->helpUrl = 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Templates';
  48                                 break;
  49                         default:
  50                                 ApiBase::dieDebug( __METHOD__, 'Unknown module name' );
  51                 }
  52
  53                 parent::__construct( $query, $moduleName, $this->prefix );
  54         }
  55
  56         public function execute() {
  57                 $this->run();
  58         }
  59
  60         public function getCacheMode( $params ) {
  61                 return 'public';
  62         }
  63
  64         public function executeGenerator( $resultPageSet ) {
  65                 $this->run( $resultPageSet );
  66         }
  67
  68         /**
  69          * @param ApiPageSet $resultPageSet
  70          */
  71         private function run( $resultPageSet = null ) {
  72                 if ( $this->getPageSet()->getGoodTitleCount() == 0 ) {
  73                         return; // nothing to do
  74                 }
  75
  76                 $params = $this->extractRequestParams();
  77
  78                 $this->addFields( [
  79                         'pl_from' => $this->prefix . '_from',
  80                         'pl_namespace' => $this->prefix . '_namespace',
  81                         'pl_title' => $this->prefix . '_title'
  82                 ] );
  83
  84                 $this->addTables( $this->table );
  85                 $this->addWhereFld( $this->prefix . '_from', array_keys( $this->getPageSet()->getGoodTitles() ) );
  86
  87                 $multiNS = true;
  88                 $multiTitle = true;
  89                 if ( $params[$this->titlesParam] ) {
  90                         // Filter the titles in PHP so our ORDER BY bug avoidance below works right.
  91                         $filterNS = $params['namespace'] ? array_flip( $params['namespace'] ) : false;
  92
  93                         $lb = new LinkBatch;
  94                         foreach ( $params[$this->titlesParam] as $t ) {
  95                                 $title = Title::newFromText( $t );
  96                                 if ( !$title ) {
  97                                         $this->addWarning( [ 'apiwarn-invalidtitle', wfEscapeWikiText( $t ) ] );
  98                                 } elseif ( !$filterNS || isset( $filterNS[$title->getNamespace()] ) ) {
  99                                         $lb->addObj( $title );
 100                                 }
 101                         }
 102                         $cond = $lb->constructSet( $this->prefix, $this->getDB() );
 103                         if ( $cond ) {
 104                                 $this->addWhere( $cond );
 105                                 $multiNS = count( $lb->data ) !== 1;
 106                                 $multiTitle = count( call_user_func_array( 'array_merge', $lb->data ) ) !== 1;
 107                         } else {
 108                                 // No titles so no results
 109                                 return;
 110                         }
 111                 } elseif ( $params['namespace'] ) {
 112                         $this->addWhereFld( $this->prefix . '_namespace', $params['namespace'] );
 113                         $multiNS = $params['namespace'] === null || count( $params['namespace'] ) !== 1;
 114                 }
 115
 116                 if ( !is_null( $params['continue'] ) ) {
 117                         $cont = explode( '|', $params['continue'] );
 118                         $this->dieContinueUsageIf( count( $cont ) != 3 );
 119                         $op = $params['dir'] == 'descending' ? '<' : '>';
 120                         $plfrom = intval( $cont[0] );
 121                         $plns = intval( $cont[1] );
 122                         $pltitle = $this->getDB()->addQuotes( $cont[2] );
 123                         $this->addWhere(
 124                                 "{$this->prefix}_from $op $plfrom OR " .
 125                                 "({$this->prefix}_from = $plfrom AND " .
 126                                 "({$this->prefix}_namespace $op $plns OR " .
 127                                 "({$this->prefix}_namespace = $plns AND " .
 128                                 "{$this->prefix}_title $op= $pltitle)))"
 129                         );
 130                 }
 131
 132                 $sort = ( $params['dir'] == 'descending' ? ' DESC' : '' );
 133                 // Here's some MySQL craziness going on: if you use WHERE foo='bar'
 134                 // and later ORDER BY foo MySQL doesn't notice the ORDER BY is pointless
 135                 // but instead goes and filesorts, because the index for foo was used
 136                 // already. To work around this, we drop constant fields in the WHERE
 137                 // clause from the ORDER BY clause
 138                 $order = [];
 139                 if ( count( $this->getPageSet()->getGoodTitles() ) != 1 ) {
 140                         $order[] = $this->prefix . '_from' . $sort;
 141                 }
 142                 if ( $multiNS ) {
 143                         $order[] = $this->prefix . '_namespace' . $sort;
 144                 }
 145                 if ( $multiTitle ) {
 146                         $order[] = $this->prefix . '_title' . $sort;
 147                 }
 148                 if ( $order ) {
 149                         $this->addOption( 'ORDER BY', $order );
 150                 }
 151                 $this->addOption( 'LIMIT', $params['limit'] + 1 );
 152
 153                 $res = $this->select( __METHOD__ );
 154
 155                 if ( is_null( $resultPageSet ) ) {
 156                         $count = 0;
 157                         foreach ( $res as $row ) {
 158                                 if ( ++$count > $params['limit'] ) {
 159                                         // We've reached the one extra which shows that
 160                                         // there are additional pages to be had. Stop here...
 161                                         $this->setContinueEnumParameter( 'continue',
 162                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 163                                         break;
 164                                 }
 165                                 $vals = [];
 166                                 ApiQueryBase::addTitleInfo( $vals, Title::makeTitle( $row->pl_namespace, $row->pl_title ) );
 167                                 $fit = $this->addPageSubItem( $row->pl_from, $vals );
 168                                 if ( !$fit ) {
 169                                         $this->setContinueEnumParameter( 'continue',
 170                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 171                                         break;
 172                                 }
 173                         }
 174                 } else {
 175                         $titles = [];
 176                         $count = 0;
 177                         foreach ( $res as $row ) {
 178                                 if ( ++$count > $params['limit'] ) {
 179                                         // We've reached the one extra which shows that
 180                                         // there are additional pages to be had. Stop here...
 181                                         $this->setContinueEnumParameter( 'continue',
 182                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 183                                         break;
 184                                 }
 185                                 $titles[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
 186                         }
 187                         $resultPageSet->populateFromTitles( $titles );
 188                 }
 189         }
 190
 191         public function getAllowedParams() {
 192                 return [
 193                         'namespace' => [
 194                                 ApiBase::PARAM_TYPE => 'namespace',
 195                                 ApiBase::PARAM_ISMULTI => true,
 196                                 ApiBase::PARAM_EXTRA_NAMESPACES => [ NS_MEDIA, NS_SPECIAL ],
 197                         ],
 198                         'limit' => [
 199                                 ApiBase::PARAM_DFLT => 10,
 200                                 ApiBase::PARAM_TYPE => 'limit',
 201                                 ApiBase::PARAM_MIN => 1,
 202                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 203                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 204                         ],
 205                         'continue' => [
 206                                 ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
 207                         ],
 208                         $this->titlesParam => [
 209                                 ApiBase::PARAM_ISMULTI => true,
 210                         ],
 211                         'dir' => [
 212                                 ApiBase::PARAM_DFLT => 'ascending',
 213                                 ApiBase::PARAM_TYPE => [
 214                                         'ascending',
 215                                         'descending'
 216                                 ]
 217                         ],
 218                 ];
 219         }
 220
 221         protected function getExamplesMessages() {
 222                 $name = $this->getModuleName();
 223                 $path = $this->getModulePath();
 224
 225                 return [
 226                         "action=query&prop={$name}&titles=Main%20Page"
 227                                 => "apihelp-{$path}-example-simple",
 228                         "action=query&generator={$name}&titles=Main%20Page&prop=info"
 229                                 => "apihelp-{$path}-example-generator",
 230                         "action=query&prop={$name}&titles=Main%20Page&{$this->prefix}namespace=2|10"
 231                                 => "apihelp-{$path}-example-namespaces",
 232                 ];
 233         }
 234
 235         public function getHelpUrls() {
 236                 return $this->helpUrl;
 237         }
 238 }