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                 $this->addWhereFld( $this->prefix . '_namespace', $params['namespace'] );
  91
  92                 if ( $params[$this->titlesParam] ) {
  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                                 } else {
  99                                         $lb->addObj( $title );
 100                                 }
 101                         }
 102                         $cond = $lb->constructSet( $this->prefix, $this->getDB() );
 103                         if ( $cond ) {
 104                                 $this->addWhere( $cond );
 105                         } else {
 106                                 // No titles so no results
 107                                 return;
 108                         }
 109                 }
 110
 111                 if ( !is_null( $params['continue'] ) ) {
 112                         $cont = explode( '|', $params['continue'] );
 113                         $this->dieContinueUsageIf( count( $cont ) != 3 );
 114                         $op = $params['dir'] == 'descending' ? '<' : '>';
 115                         $plfrom = intval( $cont[0] );
 116                         $plns = intval( $cont[1] );
 117                         $pltitle = $this->getDB()->addQuotes( $cont[2] );
 118                         $this->addWhere(
 119                                 "{$this->prefix}_from $op $plfrom OR " .
 120                                 "({$this->prefix}_from = $plfrom AND " .
 121                                 "({$this->prefix}_namespace $op $plns OR " .
 122                                 "({$this->prefix}_namespace = $plns AND " .
 123                                 "{$this->prefix}_title $op= $pltitle)))"
 124                         );
 125                 }
 126
 127                 $sort = ( $params['dir'] == 'descending' ? ' DESC' : '' );
 128                 // Here's some MySQL craziness going on: if you use WHERE foo='bar'
 129                 // and later ORDER BY foo MySQL doesn't notice the ORDER BY is pointless
 130                 // but instead goes and filesorts, because the index for foo was used
 131                 // already. To work around this, we drop constant fields in the WHERE
 132                 // clause from the ORDER BY clause
 133                 $order = [];
 134                 if ( count( $this->getPageSet()->getGoodTitles() ) != 1 ) {
 135                         $order[] = $this->prefix . '_from' . $sort;
 136                 }
 137                 if ( count( $params['namespace'] ) != 1 ) {
 138                         $order[] = $this->prefix . '_namespace' . $sort;
 139                 }
 140
 141                 $order[] = $this->prefix . '_title' . $sort;
 142                 $this->addOption( 'ORDER BY', $order );
 143                 $this->addOption( 'LIMIT', $params['limit'] + 1 );
 144
 145                 $res = $this->select( __METHOD__ );
 146
 147                 if ( is_null( $resultPageSet ) ) {
 148                         $count = 0;
 149                         foreach ( $res as $row ) {
 150                                 if ( ++$count > $params['limit'] ) {
 151                                         // We've reached the one extra which shows that
 152                                         // there are additional pages to be had. Stop here...
 153                                         $this->setContinueEnumParameter( 'continue',
 154                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 155                                         break;
 156                                 }
 157                                 $vals = [];
 158                                 ApiQueryBase::addTitleInfo( $vals, Title::makeTitle( $row->pl_namespace, $row->pl_title ) );
 159                                 $fit = $this->addPageSubItem( $row->pl_from, $vals );
 160                                 if ( !$fit ) {
 161                                         $this->setContinueEnumParameter( 'continue',
 162                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 163                                         break;
 164                                 }
 165                         }
 166                 } else {
 167                         $titles = [];
 168                         $count = 0;
 169                         foreach ( $res as $row ) {
 170                                 if ( ++$count > $params['limit'] ) {
 171                                         // We've reached the one extra which shows that
 172                                         // there are additional pages to be had. Stop here...
 173                                         $this->setContinueEnumParameter( 'continue',
 174                                                 "{$row->pl_from}|{$row->pl_namespace}|{$row->pl_title}" );
 175                                         break;
 176                                 }
 177                                 $titles[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
 178                         }
 179                         $resultPageSet->populateFromTitles( $titles );
 180                 }
 181         }
 182
 183         public function getAllowedParams() {
 184                 return [
 185                         'namespace' => [
 186                                 ApiBase::PARAM_TYPE => 'namespace',
 187                                 ApiBase::PARAM_ISMULTI => true,
 188                                 ApiBase::PARAM_EXTRA_NAMESPACES => [ NS_MEDIA, NS_SPECIAL ],
 189                         ],
 190                         'limit' => [
 191                                 ApiBase::PARAM_DFLT => 10,
 192                                 ApiBase::PARAM_TYPE => 'limit',
 193                                 ApiBase::PARAM_MIN => 1,
 194                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 195                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 196                         ],
 197                         'continue' => [
 198                                 ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
 199                         ],
 200                         $this->titlesParam => [
 201                                 ApiBase::PARAM_ISMULTI => true,
 202                         ],
 203                         'dir' => [
 204                                 ApiBase::PARAM_DFLT => 'ascending',
 205                                 ApiBase::PARAM_TYPE => [
 206                                         'ascending',
 207                                         'descending'
 208                                 ]
 209                         ],
 210                 ];
 211         }
 212
 213         protected function getExamplesMessages() {
 214                 $name = $this->getModuleName();
 215                 $path = $this->getModulePath();
 216
 217                 return [
 218                         "action=query&prop={$name}&titles=Main%20Page"
 219                                 => "apihelp-{$path}-example-simple",
 220                         "action=query&generator={$name}&titles=Main%20Page&prop=info"
 221                                 => "apihelp-{$path}-example-generator",
 222                         "action=query&prop={$name}&titles=Main%20Page&{$this->prefix}namespace=2|10"
 223                                 => "apihelp-{$path}-example-namespaces",
 224                 ];
 225         }
 226
 227         public function getHelpUrls() {
 228                 return $this->helpUrl;
 229         }
 230 }