includes/api/ApiQueryCategoryMembers.php

   1 <?php
   2 /**
   3  * API for MediaWiki 1.8+
   4  *
   5  * Created on June 14, 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 if ( !defined( 'MEDIAWIKI' ) ) {
  28         // Eclipse helper - will be ignored in production
  29         require_once( "ApiQueryBase.php" );
  30 }
  31
  32 /**
  33  * A query module to enumerate pages that belong to a category.
  34  *
  35  * @ingroup API
  36  */
  37 class ApiQueryCategoryMembers extends ApiQueryGeneratorBase {
  38
  39         public function __construct( $query, $moduleName ) {
  40                 parent::__construct( $query, $moduleName, 'cm' );
  41         }
  42
  43         public function execute() {
  44                 $this->run();
  45         }
  46
  47         public function getCacheMode( $params ) {
  48                 return 'public';
  49         }
  50
  51         public function executeGenerator( $resultPageSet ) {
  52                 $this->run( $resultPageSet );
  53         }
  54
  55         private function run( $resultPageSet = null ) {
  56                 $params = $this->extractRequestParams();
  57
  58                 $categoryTitle = Title::newFromText( $params['title'] );
  59
  60                 if ( is_null( $categoryTitle ) || $categoryTitle->getNamespace() != NS_CATEGORY ) {
  61                         $this->dieUsage( 'The category name you entered is not valid', 'invalidcategory' );
  62                 }
  63
  64                 $prop = array_flip( $params['prop'] );
  65                 $fld_ids = isset( $prop['ids'] );
  66                 $fld_title = isset( $prop['title'] );
  67                 $fld_sortkey = isset( $prop['sortkey'] );
  68                 $fld_timestamp = isset( $prop['timestamp'] );
  69
  70                 if ( is_null( $resultPageSet ) ) {
  71                         $this->addFields( array( 'cl_from', 'cl_sortkey', 'page_namespace', 'page_title' ) );
  72                         $this->addFieldsIf( 'page_id', $fld_ids );
  73                 } else {
  74                         $this->addFields( $resultPageSet->getPageTableFields() ); // will include page_ id, ns, title
  75                         $this->addFields( array( 'cl_from', 'cl_sortkey' ) );
  76                 }
  77
  78                 $this->addFieldsIf( 'cl_timestamp', $fld_timestamp || $params['sort'] == 'timestamp' );
  79                 $this->addTables( array( 'page', 'categorylinks' ) );   // must be in this order for 'USE INDEX'
  80                                                                         // Not needed after bug 10280 is applied to servers
  81                 if ( $params['sort'] == 'timestamp' ) {
  82                         $this->addOption( 'USE INDEX', 'cl_timestamp' );
  83                 } else {
  84                         $this->addOption( 'USE INDEX', 'cl_sortkey' );
  85                 }
  86
  87                 $this->addWhere( 'cl_from=page_id' );
  88                 $this->setContinuation( $params['continue'], $params['dir'] );
  89                 $this->addWhereFld( 'cl_to', $categoryTitle->getDBkey() );
  90                 // Scanning large datasets for rare categories sucks, and I already told
  91                 // how to have efficient subcategory access :-) ~~~~ (oh well, domas)
  92                 global $wgMiserMode;
  93                 $miser_ns = array();
  94                 if ( $wgMiserMode ) {
  95                         $miser_ns = $params['namespace'];
  96                 } else {
  97                         $this->addWhereFld( 'page_namespace', $params['namespace'] );
  98                 }
  99                 if ( $params['sort'] == 'timestamp' ) {
 100                         $this->addWhereRange( 'cl_timestamp', ( $params['dir'] == 'asc' ? 'newer' : 'older' ), $params['start'], $params['end'] );
 101                 } else {
 102                         $this->addWhereRange( 'cl_sortkey', ( $params['dir'] == 'asc' ? 'newer' : 'older' ), $params['startsortkey'], $params['endsortkey'] );
 103                         $this->addWhereRange( 'cl_from', ( $params['dir'] == 'asc' ? 'newer' : 'older' ), null, null );
 104                 }
 105
 106                 $limit = $params['limit'];
 107                 $this->addOption( 'LIMIT', $limit + 1 );
 108
 109                 $count = 0;
 110                 $lastSortKey = null;
 111                 $res = $this->select( __METHOD__ );
 112                 foreach ( $res as $row ) {
 113                         if ( ++ $count > $limit ) {
 114                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 115                                 // TODO: Security issue - if the user has no right to view next title, it will still be shown
 116                                 if ( $params['sort'] == 'timestamp' ) {
 117                                         $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 118                                 } else {
 119                                         $this->setContinueEnumParameter( 'continue', $this->getContinueStr( $row, $lastSortKey ) );
 120                                 }
 121                                 break;
 122                         }
 123
 124                         // Since domas won't tell anyone what he told long ago, apply
 125                         // cmnamespace here. This means the query may return 0 actual
 126                         // results, but on the other hand it could save returning 5000
 127                         // useless results to the client. ~~~~
 128                         if ( count( $miser_ns ) && !in_array( $row->page_namespace, $miser_ns ) ) {
 129                                 continue;
 130                         }
 131
 132                         if ( is_null( $resultPageSet ) ) {
 133                                 $vals = array();
 134                                 if ( $fld_ids ) {
 135                                         $vals['pageid'] = intval( $row->page_id );
 136                                 }
 137                                 if ( $fld_title ) {
 138                                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 139                                         ApiQueryBase::addTitleInfo( $vals, $title );
 140                                 }
 141                                 if ( $fld_sortkey ) {
 142                                         $vals['sortkey'] = $row->cl_sortkey;
 143                                 }
 144                                 if ( $fld_timestamp ) {
 145                                         $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $row->cl_timestamp );
 146                                 }
 147                                 $fit = $this->getResult()->addValue( array( 'query', $this->getModuleName() ),
 148                                                 null, $vals );
 149                                 if ( !$fit ) {
 150                                         if ( $params['sort'] == 'timestamp' ) {
 151                                                 $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 152                                         } else {
 153                                                 $this->setContinueEnumParameter( 'continue', $this->getContinueStr( $row, $lastSortKey ) );
 154                                         }
 155                                         break;
 156                                 }
 157                         } else {
 158                                 $resultPageSet->processDbRow( $row );
 159                         }
 160                         $lastSortKey = $row->cl_sortkey; // detect duplicate sortkeys
 161                 }
 162
 163                 if ( is_null( $resultPageSet ) ) {
 164                         $this->getResult()->setIndexedTagName_internal(
 165                                          array( 'query', $this->getModuleName() ), 'cm' );
 166                 }
 167         }
 168
 169         private function getContinueStr( $row, $lastSortKey ) {
 170                 $ret = $row->cl_sortkey . '|';
 171                 if ( $row->cl_sortkey == $lastSortKey ) { // duplicate sort key, add cl_from
 172                         $ret .= $row->cl_from;
 173                 }
 174                 return $ret;
 175         }
 176
 177         /**
 178          * Add DB WHERE clause to continue previous query based on 'continue' parameter
 179          */
 180         private function setContinuation( $continue, $dir ) {
 181                 if ( is_null( $continue ) ) {
 182                         return; // This is not a continuation request
 183                 }
 184
 185                 $pos = strrpos( $continue, '|' );
 186                 $sortkey = substr( $continue, 0, $pos );
 187                 $fromstr = substr( $continue, $pos + 1 );
 188                 $from = intval( $fromstr );
 189
 190                 if ( $from == 0 && strlen( $fromstr ) > 0 ) {
 191                         $this->dieUsage( 'Invalid continue param. You should pass the original value returned by the previous query', 'badcontinue' );
 192                 }
 193
 194                 $encSortKey = $this->getDB()->addQuotes( $sortkey );
 195                 $encFrom = $this->getDB()->addQuotes( $from );
 196
 197                 $op = ( $dir == 'desc' ? '<' : '>' );
 198
 199                 if ( $from != 0 ) {
 200                         // Duplicate sort key continue
 201                         $this->addWhere( "cl_sortkey$op$encSortKey OR (cl_sortkey=$encSortKey AND cl_from$op=$encFrom)" );
 202                 } else {
 203                         $this->addWhere( "cl_sortkey$op=$encSortKey" );
 204                 }
 205         }
 206
 207         public function getAllowedParams() {
 208                 return array(
 209                         'title' => array(
 210                                 ApiBase::PARAM_TYPE => 'string',
 211                                 ApiBase::PARAM_REQUIRED => true
 212                         ),
 213                         'prop' => array(
 214                                 ApiBase::PARAM_DFLT => 'ids|title',
 215                                 ApiBase::PARAM_ISMULTI => true,
 216                                 ApiBase::PARAM_TYPE => array (
 217                                         'ids',
 218                                         'title',
 219                                         'sortkey',
 220                                         'timestamp',
 221                                 )
 222                         ),
 223                         'namespace' => array (
 224                                 ApiBase::PARAM_ISMULTI => true,
 225                                 ApiBase::PARAM_TYPE => 'namespace',
 226                         ),
 227                         'continue' => null,
 228                         'limit' => array(
 229                                 ApiBase::PARAM_TYPE => 'limit',
 230                                 ApiBase::PARAM_DFLT => 10,
 231                                 ApiBase::PARAM_MIN => 1,
 232                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 233                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 234                         ),
 235                         'sort' => array(
 236                                 ApiBase::PARAM_DFLT => 'sortkey',
 237                                 ApiBase::PARAM_TYPE => array(
 238                                         'sortkey',
 239                                         'timestamp'
 240                                 )
 241                         ),
 242                         'dir' => array(
 243                                 ApiBase::PARAM_DFLT => 'asc',
 244                                 ApiBase::PARAM_TYPE => array(
 245                                         'asc',
 246                                         'desc'
 247                                 )
 248                         ),
 249                         'start' => array(
 250                                 ApiBase::PARAM_TYPE => 'timestamp'
 251                         ),
 252                         'end' => array(
 253                                 ApiBase::PARAM_TYPE => 'timestamp'
 254                         ),
 255                         'startsortkey' => null,
 256                         'endsortkey' => null,
 257                 );
 258         }
 259
 260         public function getParamDescription() {
 261                 global $wgMiserMode;
 262                 $p = $this->getModulePrefix();
 263                 $desc = array(
 264                         'title' => 'Which category to enumerate (required). Must include Category: prefix',
 265                         'prop' => array(
 266                                 'What pieces of information to include',
 267                                 ' ids        - Adds the page ID',
 268                                 ' title      - Adds the title and namespace ID of the page',
 269                                 ' sortkey    - Adds the sortkey used for the category',
 270                                 ' timestamp  - Adds the timestamp of when the page was included',
 271                         ),
 272                         'namespace' => 'Only include pages in these namespaces',
 273                         'sort' => 'Property to sort by',
 274                         'dir' => 'In which direction to sort',
 275                         'start' => "Timestamp to start listing from. Can only be used with {$p}sort=timestamp",
 276                         'end' => "Timestamp to end listing at. Can only be used with {$p}sort=timestamp",
 277                         'startsortkey' => "Sortkey to start listing from. Can only be used with {$p}sort=sortkey",
 278                         'endsortkey' => "Sortkey to end listing at. Can only be used with {$p}sort=sortkey",
 279                         'continue' => 'For large categories, give the value retured from previous query',
 280                         'limit' => 'The maximum number of pages to return.',
 281                 );
 282                 if ( $wgMiserMode ) {
 283                         $desc['namespace'] = array(
 284                                 $desc['namespace'],
 285                                 'NOTE: Due to $wgMiserMode, using this may result in fewer than "limit" results',
 286                                 'returned before continuing; in extreme cases, zero results may be returned',
 287                         );
 288                 }
 289                 return $desc;
 290         }
 291
 292         public function getDescription() {
 293                 return 'List all pages in a given category';
 294         }
 295
 296         public function getPossibleErrors() {
 297                 return array_merge( parent::getPossibleErrors(), array(
 298                         array( 'code' => 'notitle', 'info' => 'The cmtitle parameter is required' ),
 299                         array( 'code' => 'invalidcategory', 'info' => 'The category name you entered is not valid' ),
 300                         array( 'code' => 'badcontinue', 'info' => 'Invalid continue param. You should pass the original value returned by the previous query' ),
 301                 ) );
 302         }
 303
 304         protected function getExamples() {
 305                 return array(
 306                         'Get first 10 pages in [[Category:Physics]]:',
 307                         '  api.php?action=query&list=categorymembers&cmtitle=Category:Physics',
 308                         'Get page info about first 10 pages in [[Category:Physics]]:',
 309                         '  api.php?action=query&generator=categorymembers&gcmtitle=Category:Physics&prop=info',
 310                 );
 311         }
 312
 313         public function getVersion() {
 314                 return __CLASS__ . ': $Id$';
 315         }
 316 }