includes/api/ApiQueryCategoryMembers.php

   1 <?php
   2 /**
   3  *
   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                 $this->requireOnlyOneParameter( $params, 'title', 'pageid' );
  59
  60                 if ( isset( $params['title'] ) ) {
  61                         $categoryTitle = Title::newFromText( $params['title'] );
  62
  63                         if ( is_null( $categoryTitle ) || $categoryTitle->getNamespace() != NS_CATEGORY ) {
  64                                 $this->dieUsage( 'The category name you entered is not valid', 'invalidcategory' );
  65                         }
  66                 } elseif( isset( $params['pageid'] ) ) {
  67                         $categoryTitle = Title::newFromID( $params['pageid'] );
  68
  69                         if ( !$categoryTitle ) {
  70                                 $this->dieUsageMsg( array( 'nosuchpageid', $params['pageid'] ) );
  71                         } elseif ( $categoryTitle->getNamespace() != NS_CATEGORY ) {
  72                                 $this->dieUsage( 'The category name you entered is not valid', 'invalidcategory' );
  73                         }
  74                 }
  75
  76                 $prop = array_flip( $params['prop'] );
  77                 $fld_ids = isset( $prop['ids'] );
  78                 $fld_title = isset( $prop['title'] );
  79                 $fld_sortkey = isset( $prop['sortkey'] );
  80                 $fld_timestamp = isset( $prop['timestamp'] );
  81
  82                 if ( is_null( $resultPageSet ) ) {
  83                         $this->addFields( array( 'cl_from', 'cl_sortkey', 'page_namespace', 'page_title' ) );
  84                         $this->addFieldsIf( 'page_id', $fld_ids );
  85                 } else {
  86                         $this->addFields( $resultPageSet->getPageTableFields() ); // will include page_ id, ns, title
  87                         $this->addFields( array( 'cl_from', 'cl_sortkey' ) );
  88                 }
  89
  90                 $this->addFieldsIf( 'cl_timestamp', $fld_timestamp || $params['sort'] == 'timestamp' );
  91                 $this->addTables( array( 'page', 'categorylinks' ) );   // must be in this order for 'USE INDEX'
  92                                                                         // Not needed after bug 10280 is applied to servers
  93                 if ( $params['sort'] == 'timestamp' ) {
  94                         $this->addOption( 'USE INDEX', 'cl_timestamp' );
  95                 } else {
  96                         $this->addOption( 'USE INDEX', 'cl_sortkey' );
  97                 }
  98
  99                 $this->addWhere( 'cl_from=page_id' );
 100                 $this->setContinuation( $params['continue'], $params['dir'] );
 101                 $this->addWhereFld( 'cl_to', $categoryTitle->getDBkey() );
 102                 // Scanning large datasets for rare categories sucks, and I already told
 103                 // how to have efficient subcategory access :-) ~~~~ (oh well, domas)
 104                 global $wgMiserMode;
 105                 $miser_ns = array();
 106                 if ( $wgMiserMode ) {
 107                         $miser_ns = $params['namespace'];
 108                 } else {
 109                         $this->addWhereFld( 'page_namespace', $params['namespace'] );
 110                 }
 111                 if ( $params['sort'] == 'timestamp' ) {
 112                         $this->addWhereRange( 'cl_timestamp', ( $params['dir'] == 'asc' ? 'newer' : 'older' ), $params['start'], $params['end'] );
 113                 } else {
 114                         $this->addWhereRange( 'cl_sortkey', ( $params['dir'] == 'asc' ? 'newer' : 'older' ), $params['startsortkey'], $params['endsortkey'] );
 115                         $this->addWhereRange( 'cl_from', ( $params['dir'] == 'asc' ? 'newer' : 'older' ), null, null );
 116                 }
 117
 118                 $limit = $params['limit'];
 119                 $this->addOption( 'LIMIT', $limit + 1 );
 120
 121                 $count = 0;
 122                 $lastSortKey = null;
 123                 $res = $this->select( __METHOD__ );
 124                 foreach ( $res as $row ) {
 125                         if ( ++ $count > $limit ) {
 126                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 127                                 // TODO: Security issue - if the user has no right to view next title, it will still be shown
 128                                 if ( $params['sort'] == 'timestamp' ) {
 129                                         $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 130                                 } else {
 131                                         $this->setContinueEnumParameter( 'continue', $this->getContinueStr( $row, $lastSortKey ) );
 132                                 }
 133                                 break;
 134                         }
 135
 136                         // Since domas won't tell anyone what he told long ago, apply
 137                         // cmnamespace here. This means the query may return 0 actual
 138                         // results, but on the other hand it could save returning 5000
 139                         // useless results to the client. ~~~~
 140                         if ( count( $miser_ns ) && !in_array( $row->page_namespace, $miser_ns ) ) {
 141                                 continue;
 142                         }
 143
 144                         if ( is_null( $resultPageSet ) ) {
 145                                 $vals = array();
 146                                 if ( $fld_ids ) {
 147                                         $vals['pageid'] = intval( $row->page_id );
 148                                 }
 149                                 if ( $fld_title ) {
 150                                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 151                                         ApiQueryBase::addTitleInfo( $vals, $title );
 152                                 }
 153                                 if ( $fld_sortkey ) {
 154                                         $vals['sortkey'] = $row->cl_sortkey;
 155                                 }
 156                                 if ( $fld_timestamp ) {
 157                                         $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $row->cl_timestamp );
 158                                 }
 159                                 $fit = $this->getResult()->addValue( array( 'query', $this->getModuleName() ),
 160                                                 null, $vals );
 161                                 if ( !$fit ) {
 162                                         if ( $params['sort'] == 'timestamp' ) {
 163                                                 $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 164                                         } else {
 165                                                 $this->setContinueEnumParameter( 'continue', $this->getContinueStr( $row, $lastSortKey ) );
 166                                         }
 167                                         break;
 168                                 }
 169                         } else {
 170                                 $resultPageSet->processDbRow( $row );
 171                         }
 172                         $lastSortKey = $row->cl_sortkey; // detect duplicate sortkeys
 173                 }
 174
 175                 if ( is_null( $resultPageSet ) ) {
 176                         $this->getResult()->setIndexedTagName_internal(
 177                                          array( 'query', $this->getModuleName() ), 'cm' );
 178                 }
 179         }
 180
 181         private function getContinueStr( $row, $lastSortKey ) {
 182                 $ret = $row->cl_sortkey . '|';
 183                 if ( $row->cl_sortkey == $lastSortKey ) { // duplicate sort key, add cl_from
 184                         $ret .= $row->cl_from;
 185                 }
 186                 return $ret;
 187         }
 188
 189         /**
 190          * Add DB WHERE clause to continue previous query based on 'continue' parameter
 191          */
 192         private function setContinuation( $continue, $dir ) {
 193                 if ( is_null( $continue ) ) {
 194                         return; // This is not a continuation request
 195                 }
 196
 197                 $pos = strrpos( $continue, '|' );
 198                 $sortkey = substr( $continue, 0, $pos );
 199                 $fromstr = substr( $continue, $pos + 1 );
 200                 $from = intval( $fromstr );
 201
 202                 if ( $from == 0 && strlen( $fromstr ) > 0 ) {
 203                         $this->dieUsage( 'Invalid continue param. You should pass the original value returned by the previous query', 'badcontinue' );
 204                 }
 205
 206                 $encSortKey = $this->getDB()->addQuotes( $sortkey );
 207                 $encFrom = $this->getDB()->addQuotes( $from );
 208
 209                 $op = ( $dir == 'desc' ? '<' : '>' );
 210
 211                 if ( $from != 0 ) {
 212                         // Duplicate sort key continue
 213                         $this->addWhere( "cl_sortkey$op$encSortKey OR (cl_sortkey=$encSortKey AND cl_from$op=$encFrom)" );
 214                 } else {
 215                         $this->addWhere( "cl_sortkey$op=$encSortKey" );
 216                 }
 217         }
 218
 219         public function getAllowedParams() {
 220                 return array(
 221                         'title' => array(
 222                                 ApiBase::PARAM_TYPE => 'string',
 223                         ),
 224                         'pageid' => array(
 225                                 ApiBase::PARAM_TYPE => 'integer'
 226                         ),
 227                         'prop' => array(
 228                                 ApiBase::PARAM_DFLT => 'ids|title',
 229                                 ApiBase::PARAM_ISMULTI => true,
 230                                 ApiBase::PARAM_TYPE => array (
 231                                         'ids',
 232                                         'title',
 233                                         'sortkey',
 234                                         'timestamp',
 235                                 )
 236                         ),
 237                         'namespace' => array (
 238                                 ApiBase::PARAM_ISMULTI => true,
 239                                 ApiBase::PARAM_TYPE => 'namespace',
 240                         ),
 241                         'continue' => null,
 242                         'limit' => array(
 243                                 ApiBase::PARAM_TYPE => 'limit',
 244                                 ApiBase::PARAM_DFLT => 10,
 245                                 ApiBase::PARAM_MIN => 1,
 246                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 247                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 248                         ),
 249                         'sort' => array(
 250                                 ApiBase::PARAM_DFLT => 'sortkey',
 251                                 ApiBase::PARAM_TYPE => array(
 252                                         'sortkey',
 253                                         'timestamp'
 254                                 )
 255                         ),
 256                         'dir' => array(
 257                                 ApiBase::PARAM_DFLT => 'asc',
 258                                 ApiBase::PARAM_TYPE => array(
 259                                         'asc',
 260                                         'desc'
 261                                 )
 262                         ),
 263                         'start' => array(
 264                                 ApiBase::PARAM_TYPE => 'timestamp'
 265                         ),
 266                         'end' => array(
 267                                 ApiBase::PARAM_TYPE => 'timestamp'
 268                         ),
 269                         'startsortkey' => null,
 270                         'endsortkey' => null,
 271                 );
 272         }
 273
 274         public function getParamDescription() {
 275                 global $wgMiserMode;
 276                 $p = $this->getModulePrefix();
 277                 $desc = array(
 278                         'title' => 'Which category to enumerate (required). Must include Category: prefix. Cannot be used together with cmpageid',
 279                         'pageid' => 'Page ID of the category to enumerate. Cannot be used together with cmtitle',
 280                         'prop' => array(
 281                                 'What pieces of information to include',
 282                                 ' ids        - Adds the page ID',
 283                                 ' title      - Adds the title and namespace ID of the page',
 284                                 ' sortkey    - Adds the sortkey used for the category',
 285                                 ' timestamp  - Adds the timestamp of when the page was included',
 286                         ),
 287                         'namespace' => 'Only include pages in these namespaces',
 288                         'sort' => 'Property to sort by',
 289                         'dir' => 'In which direction to sort',
 290                         'start' => "Timestamp to start listing from. Can only be used with {$p}sort=timestamp",
 291                         'end' => "Timestamp to end listing at. Can only be used with {$p}sort=timestamp",
 292                         'startsortkey' => "Sortkey to start listing from. Can only be used with {$p}sort=sortkey",
 293                         'endsortkey' => "Sortkey to end listing at. Can only be used with {$p}sort=sortkey",
 294                         'continue' => 'For large categories, give the value retured from previous query',
 295                         'limit' => 'The maximum number of pages to return.',
 296                 );
 297                 if ( $wgMiserMode ) {
 298                         $desc['namespace'] = array(
 299                                 $desc['namespace'],
 300                                 'NOTE: Due to $wgMiserMode, using this may result in fewer than "limit" results',
 301                                 'returned before continuing; in extreme cases, zero results may be returned',
 302                         );
 303                 }
 304                 return $desc;
 305         }
 306
 307         public function getDescription() {
 308                 return 'List all pages in a given category';
 309         }
 310
 311         public function getPossibleErrors() {
 312                 return array_merge( parent::getPossibleErrors(), array(
 313                         array( 'code' => 'cmmissingparam', 'info' => 'One of the parameters title, pageid is required' ),
 314                         array( 'code' => 'cminvalidparammix', 'info' => 'The parameters title, pageid can not be used together' ),
 315                         array( 'code' => 'invalidcategory', 'info' => 'The category name you entered is not valid' ),
 316                         array( 'code' => 'badcontinue', 'info' => 'Invalid continue param. You should pass the original value returned by the previous query' ),
 317                         array( 'nosuchpageid', 'pageid' ),
 318                 ) );
 319         }
 320
 321         protected function getExamples() {
 322                 return array(
 323                         'Get first 10 pages in [[Category:Physics]]:',
 324                         '  api.php?action=query&list=categorymembers&cmtitle=Category:Physics',
 325                         'Get page info about first 10 pages in [[Category:Physics]]:',
 326                         '  api.php?action=query&generator=categorymembers&gcmtitle=Category:Physics&prop=info',
 327                 );
 328         }
 329
 330         public function getVersion() {
 331                 return __CLASS__ . ': $Id$';
 332         }
 333 }