includes/api/ApiQueryLinks.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on May 12, 2007
   6  *
   7  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   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  */
  26
  27 /**
  28  * A query module to list all wiki links on a given set of pages.
  29  *
  30  * @ingroup API
  31  */
  32 class ApiQueryLinks extends ApiQueryGeneratorBase {
  33
  34         const LINKS = 'links';
  35         const TEMPLATES = 'templates';
  36
  37         private $table, $prefix, $titlesParam, $helpUrl;
  38
  39         public function __construct( ApiQuery $query, $moduleName ) {
  40                 switch ( $moduleName ) {
  41                         case self::LINKS:
  42                                 $this->table = 'pagelinks';
  43                                 $this->prefix = 'pl';
  44                                 $this->titlesParam = 'titles';
  45                                 $this->helpUrl = 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Links';
  46                                 break;
  47                         case self::TEMPLATES:
  48                                 $this->table = 'templatelinks';
  49                                 $this->prefix = 'tl';
  50                                 $this->titlesParam = 'templates';
  51                                 $this->helpUrl = 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Templates';
  52                                 break;
  53                         default:
  54                                 ApiBase::dieDebug( __METHOD__, 'Unknown module name' );
  55                 }
  56
  57                 parent::__construct( $query, $moduleName, $this->prefix );
  58         }
  59
  60         public function execute() {
  61                 $this->run();
  62         }
  63
  64         public function getCacheMode( $params ) {
  65                 return 'public';
  66         }
  67
  68         public function executeGenerator( $resultPageSet ) {
  69                 $this->run( $resultPageSet );
  70         }
  71
  72         /**
  73          * @param ApiPageSet $resultPageSet
  74          */
  75         private function run( $resultPageSet = null ) {
  76                 if ( $this->getPageSet()->getGoodTitleCount() == 0 ) {
  77                         return; // nothing to do
  78                 }
  79
  80                 $params = $this->extractRequestParams();
  81
  82                 $this->addFields( [
  83                         'pl_from' => $this->prefix . '_from',
  84                         'pl_namespace' => $this->prefix . '_namespace',
  85                         'pl_title' => $this->prefix . '_title'
  86                 ] );
  87
  88                 $this->addTables( $this->table );
  89                 $this->addWhereFld( $this->prefix . '_from', array_keys( $this->getPageSet()->getGoodTitles() ) );
  90
  91                 $multiNS = true;
  92                 $multiTitle = true;
  93                 if ( $params[$this->titlesParam] ) {
  94                         // Filter the titles in PHP so our ORDER BY bug avoidance below works right.
  95                         $filterNS = $params['namespace'] ? array_flip( $params['namespace'] ) : false;
  96
  97                         $lb = new LinkBatch;
  98                         foreach ( $params[$this->titlesParam] as $t ) {
  99                                 $title = Title::newFromText( $t );
 100                                 if ( !$title ) {
 101                                         $this->addWarning( [ 'apiwarn-invalidtitle', wfEscapeWikiText( $t ) ] );
 102                                 } elseif ( !$filterNS || isset( $filterNS[$title->getNamespace()] ) ) {
 103                                         $lb->addObj( $title );
 104                                 }
 105                         }
 106                         $cond = $lb->constructSet( $this->prefix, $this->getDB() );
 107                         if ( $cond ) {
 108                                 $this->addWhere( $cond );
 109                                 $multiNS = count( $lb->data ) !== 1;
 110                                 $multiTitle = count( call_user_func_array( 'array_merge', $lb->data ) ) !== 1;
 111                         } else {
 112                                 // No titles so no results
 113                                 return;
 114                         }
 115                 } elseif ( $params['namespace'] ) {
 116                         $this->addWhereFld( $this->prefix . '_namespace', $params['namespace'] );
 117                         $multiNS = count( $params['namespace'] ) !== 1;
 118                 }
 119
 120                 if ( !is_null( $params['continue'] ) ) {
 121                         $cont = explode( '|', $params['continue'] );
 122                         $this->dieContinueUsageIf( count( $cont ) != 3 );
 123                         $op = $params['dir'] == 'descending' ? '<' : '>';
 124                         $plfrom = intval( $cont[0] );
 125                         $plns = intval( $cont[1] );
 126                         $pltitle = $this->getDB()->addQuotes( $cont[2] );
 127                         $this->addWhere(
 128                                 "{$this->prefix}_from $op $plfrom OR " .
 129                                 "({$this->prefix}_from = $plfrom AND " .
 130                                 "({$this->prefix}_namespace $op $plns OR " .
 131                                 "({$this->prefix}_namespace = $plns AND " .
 132                                 "{$this->prefix}_title $op= $pltitle)))"
 133                         );
 134                 }
 135
 136                 $sort = ( $params['dir'] == 'descending' ? ' DESC' : '' );
 137                 // Here's some MySQL craziness going on: if you use WHERE foo='bar'
 138                 // and later ORDER BY foo MySQL doesn't notice the ORDER BY is pointless
 139                 // but instead goes and filesorts, because the index for foo was used
 140                 // already. To work around this, we drop constant fields in the WHERE
 141                 // clause from the ORDER BY clause
 142                 $order = [];
 143                 if ( count( $this->getPageSet()->getGoodTitles() ) != 1 ) {
 144                         $order[] = $this->prefix . '_from' . $sort;
 145                 }
 146                 if ( $multiNS ) {
 147                         $order[] = $this->prefix . '_namespace' . $sort;
 148                 }
 149                 if ( $multiTitle ) {
 150                         $order[] = $this->prefix . '_title' . $sort;
 151                 }
 152                 if ( $order ) {
 153                         $this->addOption( 'ORDER BY', $order );
 154                 }
 155                 $this->addOption( 'LIMIT', $params['limit'] + 1 );
 156
 157                 $res = $this->select( __METHOD__ );
 158
 159                 if ( is_null( $resultPageSet ) ) {
 160                         $count = 0;
 161                         foreach ( $res as $row ) {
 162                                 if ( ++$count > $params['limit'] ) {
 163                                         // We've reached the one extra which shows that
 164                                         // there are additional pages to be had. Stop here...
 165                                         $this->setContinueEnumParameter( 'continue',
 166                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 167                                         break;
 168                                 }
 169                                 $vals = [];
 170                                 ApiQueryBase::addTitleInfo( $vals, Title::makeTitle( $row->pl_namespace, $row->pl_title ) );
 171                                 $fit = $this->addPageSubItem( $row->pl_from, $vals );
 172                                 if ( !$fit ) {
 173                                         $this->setContinueEnumParameter( 'continue',
 174                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 175                                         break;
 176                                 }
 177                         }
 178                 } else {
 179                         $titles = [];
 180                         $count = 0;
 181                         foreach ( $res as $row ) {
 182                                 if ( ++$count > $params['limit'] ) {
 183                                         // We've reached the one extra which shows that
 184                                         // there are additional pages to be had. Stop here...
 185                                         $this->setContinueEnumParameter( 'continue',
 186                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 187                                         break;
 188                                 }
 189                                 $titles[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
 190                         }
 191                         $resultPageSet->populateFromTitles( $titles );
 192                 }
 193         }
 194
 195         public function getAllowedParams() {
 196                 return [
 197                         'namespace' => [
 198                                 ApiBase::PARAM_TYPE => 'namespace',
 199                                 ApiBase::PARAM_ISMULTI => true,
 200                                 ApiBase::PARAM_EXTRA_NAMESPACES => [ NS_MEDIA, NS_SPECIAL ],
 201                         ],
 202                         'limit' => [
 203                                 ApiBase::PARAM_DFLT => 10,
 204                                 ApiBase::PARAM_TYPE => 'limit',
 205                                 ApiBase::PARAM_MIN => 1,
 206                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 207                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 208                         ],
 209                         'continue' => [
 210                                 ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
 211                         ],
 212                         $this->titlesParam => [
 213                                 ApiBase::PARAM_ISMULTI => true,
 214                         ],
 215                         'dir' => [
 216                                 ApiBase::PARAM_DFLT => 'ascending',
 217                                 ApiBase::PARAM_TYPE => [
 218                                         'ascending',
 219                                         'descending'
 220                                 ]
 221                         ],
 222                 ];
 223         }
 224
 225         protected function getExamplesMessages() {
 226                 $name = $this->getModuleName();
 227                 $path = $this->getModulePath();
 228
 229                 return [
 230                         "action=query&prop={$name}&titles=Main%20Page"
 231                                 => "apihelp-{$path}-example-simple",
 232                         "action=query&generator={$name}&titles=Main%20Page&prop=info"
 233                                 => "apihelp-{$path}-example-generator",
 234                         "action=query&prop={$name}&titles=Main%20Page&{$this->prefix}namespace=2|10"
 235                                 => "apihelp-{$path}-example-namespaces",
 236                 ];
 237         }
 238
 239         public function getHelpUrls() {
 240                 return $this->helpUrl;
 241         }
 242 }