includes/api/ApiQueryCategories.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on May 13, 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 enumerate categories the set of pages belong to.
  29  *
  30  * @ingroup API
  31  */
  32 class ApiQueryCategories extends ApiQueryGeneratorBase {
  33
  34         public function __construct( ApiQuery $query, $moduleName ) {
  35                 parent::__construct( $query, $moduleName, 'cl' );
  36         }
  37
  38         public function execute() {
  39                 $this->run();
  40         }
  41
  42         public function getCacheMode( $params ) {
  43                 return 'public';
  44         }
  45
  46         public function executeGenerator( $resultPageSet ) {
  47                 $this->run( $resultPageSet );
  48         }
  49
  50         /**
  51          * @param ApiPageSet $resultPageSet
  52          */
  53         private function run( $resultPageSet = null ) {
  54                 if ( $this->getPageSet()->getGoodTitleCount() == 0 ) {
  55                         return; // nothing to do
  56                 }
  57
  58                 $params = $this->extractRequestParams();
  59                 $prop = array_flip( (array)$params['prop'] );
  60                 $show = array_flip( (array)$params['show'] );
  61
  62                 $this->addFields( array(
  63                         'cl_from',
  64                         'cl_to'
  65                 ) );
  66
  67                 $this->addFieldsIf( array( 'cl_sortkey', 'cl_sortkey_prefix' ), isset( $prop['sortkey'] ) );
  68                 $this->addFieldsIf( 'cl_timestamp', isset( $prop['timestamp'] ) );
  69
  70                 $this->addTables( 'categorylinks' );
  71                 $this->addWhereFld( 'cl_from', array_keys( $this->getPageSet()->getGoodTitles() ) );
  72                 if ( !is_null( $params['categories'] ) ) {
  73                         $cats = array();
  74                         foreach ( $params['categories'] as $cat ) {
  75                                 $title = Title::newFromText( $cat );
  76                                 if ( !$title || $title->getNamespace() != NS_CATEGORY ) {
  77                                         $this->setWarning( "\"$cat\" is not a category" );
  78                                 } else {
  79                                         $cats[] = $title->getDBkey();
  80                                 }
  81                         }
  82                         $this->addWhereFld( 'cl_to', $cats );
  83                 }
  84
  85                 if ( !is_null( $params['continue'] ) ) {
  86                         $cont = explode( '|', $params['continue'] );
  87                         $this->dieContinueUsageIf( count( $cont ) != 2 );
  88                         $op = $params['dir'] == 'descending' ? '<' : '>';
  89                         $clfrom = intval( $cont[0] );
  90                         $clto = $this->getDB()->addQuotes( $cont[1] );
  91                         $this->addWhere(
  92                                 "cl_from $op $clfrom OR " .
  93                                 "(cl_from = $clfrom AND " .
  94                                 "cl_to $op= $clto)"
  95                         );
  96                 }
  97
  98                 if ( isset( $show['hidden'] ) && isset( $show['!hidden'] ) ) {
  99                         $this->dieUsageMsg( 'show' );
 100                 }
 101                 if ( isset( $show['hidden'] ) || isset( $show['!hidden'] ) || isset( $prop['hidden'] ) ) {
 102                         $this->addOption( 'STRAIGHT_JOIN' );
 103                         $this->addTables( array( 'page', 'page_props' ) );
 104                         $this->addFieldsIf( 'pp_propname', isset( $prop['hidden'] ) );
 105                         $this->addJoinConds( array(
 106                                 'page' => array( 'LEFT JOIN', array(
 107                                         'page_namespace' => NS_CATEGORY,
 108                                         'page_title = cl_to' ) ),
 109                                 'page_props' => array( 'LEFT JOIN', array(
 110                                         'pp_page=page_id',
 111                                         'pp_propname' => 'hiddencat' ) )
 112                         ) );
 113                         if ( isset( $show['hidden'] ) ) {
 114                                 $this->addWhere( array( 'pp_propname IS NOT NULL' ) );
 115                         } elseif ( isset( $show['!hidden'] ) ) {
 116                                 $this->addWhere( array( 'pp_propname IS NULL' ) );
 117                         }
 118                 }
 119
 120                 $this->addOption( 'USE INDEX', array( 'categorylinks' => 'cl_from' ) );
 121
 122                 $sort = ( $params['dir'] == 'descending' ? ' DESC' : '' );
 123                 // Don't order by cl_from if it's constant in the WHERE clause
 124                 if ( count( $this->getPageSet()->getGoodTitles() ) == 1 ) {
 125                         $this->addOption( 'ORDER BY', 'cl_to' . $sort );
 126                 } else {
 127                         $this->addOption( 'ORDER BY', array(
 128                                 'cl_from' . $sort,
 129                                 'cl_to' . $sort
 130                         ) );
 131                 }
 132
 133                 $res = $this->select( __METHOD__ );
 134
 135                 $count = 0;
 136                 if ( is_null( $resultPageSet ) ) {
 137                         foreach ( $res as $row ) {
 138                                 if ( ++$count > $params['limit'] ) {
 139                                         // We've reached the one extra which shows that
 140                                         // there are additional pages to be had. Stop here...
 141                                         $this->setContinueEnumParameter( 'continue', $row->cl_from . '|' . $row->cl_to );
 142                                         break;
 143                                 }
 144
 145                                 $title = Title::makeTitle( NS_CATEGORY, $row->cl_to );
 146                                 $vals = array();
 147                                 ApiQueryBase::addTitleInfo( $vals, $title );
 148                                 if ( isset( $prop['sortkey'] ) ) {
 149                                         $vals['sortkey'] = bin2hex( $row->cl_sortkey );
 150                                         $vals['sortkeyprefix'] = $row->cl_sortkey_prefix;
 151                                 }
 152                                 if ( isset( $prop['timestamp'] ) ) {
 153                                         $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $row->cl_timestamp );
 154                                 }
 155                                 if ( isset( $prop['hidden'] ) && !is_null( $row->pp_propname ) ) {
 156                                         $vals['hidden'] = '';
 157                                 }
 158
 159                                 $fit = $this->addPageSubItem( $row->cl_from, $vals );
 160                                 if ( !$fit ) {
 161                                         $this->setContinueEnumParameter( 'continue', $row->cl_from . '|' . $row->cl_to );
 162                                         break;
 163                                 }
 164                         }
 165                 } else {
 166                         $titles = array();
 167                         foreach ( $res as $row ) {
 168                                 if ( ++$count > $params['limit'] ) {
 169                                         // We've reached the one extra which shows that
 170                                         // there are additional pages to be had. Stop here...
 171                                         $this->setContinueEnumParameter( 'continue', $row->cl_from . '|' . $row->cl_to );
 172                                         break;
 173                                 }
 174
 175                                 $titles[] = Title::makeTitle( NS_CATEGORY, $row->cl_to );
 176                         }
 177                         $resultPageSet->populateFromTitles( $titles );
 178                 }
 179         }
 180
 181         public function getAllowedParams() {
 182                 return array(
 183                         'prop' => array(
 184                                 ApiBase::PARAM_ISMULTI => true,
 185                                 ApiBase::PARAM_TYPE => array(
 186                                         'sortkey',
 187                                         'timestamp',
 188                                         'hidden',
 189                                 )
 190                         ),
 191                         'show' => array(
 192                                 ApiBase::PARAM_ISMULTI => true,
 193                                 ApiBase::PARAM_TYPE => array(
 194                                         'hidden',
 195                                         '!hidden',
 196                                 )
 197                         ),
 198                         'limit' => array(
 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' => null,
 206                         'categories' => array(
 207                                 ApiBase::PARAM_ISMULTI => true,
 208                         ),
 209                         'dir' => array(
 210                                 ApiBase::PARAM_DFLT => 'ascending',
 211                                 ApiBase::PARAM_TYPE => array(
 212                                         'ascending',
 213                                         'descending'
 214                                 )
 215                         ),
 216                 );
 217         }
 218
 219         public function getParamDescription() {
 220                 return array(
 221                         'prop' => array(
 222                                 'Which additional properties to get for each category',
 223                                 ' sortkey    - Adds the sortkey (hexadecimal string) and sortkey prefix',
 224                                 '              (human-readable part) for the category',
 225                                 ' timestamp  - Adds timestamp of when the category was added',
 226                                 ' hidden     - Tags categories that are hidden with __HIDDENCAT__',
 227                         ),
 228                         'limit' => 'How many categories to return',
 229                         'show' => 'Which kind of categories to show',
 230                         'continue' => 'When more results are available, use this to continue',
 231                         'categories' => 'Only list these categories. Useful for checking ' .
 232                                 'whether a certain page is in a certain category',
 233                         'dir' => 'The direction in which to list',
 234                 );
 235         }
 236
 237         public function getResultProperties() {
 238                 return array(
 239                         '' => array(
 240                                 'ns' => 'namespace',
 241                                 'title' => 'string'
 242                         ),
 243                         'sortkey' => array(
 244                                 'sortkey' => 'string',
 245                                 'sortkeyprefix' => 'string'
 246                         ),
 247                         'timestamp' => array(
 248                                 'timestamp' => 'timestamp'
 249                         ),
 250                         'hidden' => array(
 251                                 'hidden' => 'boolean'
 252                         )
 253                 );
 254         }
 255
 256         public function getDescription() {
 257                 return 'List all categories the page(s) belong to.';
 258         }
 259
 260         public function getPossibleErrors() {
 261                 return array_merge( parent::getPossibleErrors(), array(
 262                         array( 'show' ),
 263                 ) );
 264         }
 265
 266         public function getExamples() {
 267                 return array(
 268                         'api.php?action=query&prop=categories&titles=Albert%20Einstein'
 269                                 => 'Get a list of categories [[Albert Einstein]] belongs to',
 270                         'api.php?action=query&generator=categories&titles=Albert%20Einstein&prop=info'
 271                                 => 'Get information about all categories used in the [[Albert Einstein]]',
 272                 );
 273         }
 274
 275         public function getHelpUrls() {
 276                 return 'https://www.mediawiki.org/wiki/API:Properties#categories_.2F_cl';
 277         }
 278 }