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                 $fld_type = isset( $prop['type'] );
  82
  83                 if ( is_null( $resultPageSet ) ) {
  84                         $this->addFields( array( 'cl_from', 'cl_sortkey', 'page_namespace', 'page_title' ) );
  85                         $this->addFieldsIf( 'page_id', $fld_ids );
  86                 } else {
  87                         $this->addFields( $resultPageSet->getPageTableFields() ); // will include page_ id, ns, title
  88                         $this->addFields( array( 'cl_from', 'cl_sortkey' ) );
  89                 }
  90
  91                 $this->addFieldsIf( 'cl_timestamp', $fld_timestamp || $params['sort'] == 'timestamp' );
  92                 $this->addFieldsIf( 'cl_type', $fld_type );
  93
  94                 $this->addTables( array( 'page', 'categorylinks' ) );   // must be in this order for 'USE INDEX'
  95
  96                 $this->addWhereFld( 'cl_to', $categoryTitle->getDBkey() );
  97                 $this->addWhereFld( 'cl_type', $params['type'] );
  98
  99                 // Scanning large datasets for rare categories sucks, and I already told
 100                 // how to have efficient subcategory access :-) ~~~~ (oh well, domas)
 101                 global $wgMiserMode;
 102                 $miser_ns = array();
 103                 if ( $wgMiserMode ) {
 104                         $miser_ns = $params['namespace'];
 105                 } else {
 106                         $this->addWhereFld( 'page_namespace', $params['namespace'] );
 107                 }
 108
 109                 $dir = $params['dir'] == 'asc' ? 'newer' : 'older';
 110
 111                 if ( $params['sort'] == 'timestamp' ) {
 112                         $this->addWhereRange( 'cl_timestamp',
 113                                 $dir,
 114                                 $params['start'],
 115                                 $params['end'] );
 116
 117                         $this->addOption( 'USE INDEX', 'cl_timestamp' );
 118                 } else {
 119                         $this->addWhereRange( 'cl_sortkey',
 120                                 $dir,
 121                                 $params['startsortkey'],
 122                                 $params['endsortkey'] );
 123
 124                         $this->addWhereRange( 'cl_from', $dir, null, null );
 125                         $this->addOption( 'USE INDEX', 'cl_sortkey' );
 126                 }
 127
 128                 $this->addWhere( 'cl_from=page_id' );
 129
 130                 $this->setContinuation( $params['continue'], $params['dir'] );
 131
 132                 $limit = $params['limit'];
 133                 $this->addOption( 'LIMIT', $limit + 1 );
 134
 135                 $count = 0;
 136                 $lastSortKey = null;
 137                 $res = $this->select( __METHOD__ );
 138                 foreach ( $res as $row ) {
 139                         if ( ++ $count > $limit ) {
 140                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 141                                 // TODO: Security issue - if the user has no right to view next title, it will still be shown
 142                                 if ( $params['sort'] == 'timestamp' ) {
 143                                         $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 144                                 } else {
 145                                         $this->setContinueEnumParameter( 'continue', $this->getContinueStr( $row, $lastSortKey ) );
 146                                 }
 147                                 break;
 148                         }
 149
 150                         // Since domas won't tell anyone what he told long ago, apply
 151                         // cmnamespace here. This means the query may return 0 actual
 152                         // results, but on the other hand it could save returning 5000
 153                         // useless results to the client. ~~~~
 154                         if ( count( $miser_ns ) && !in_array( $row->page_namespace, $miser_ns ) ) {
 155                                 continue;
 156                         }
 157
 158                         if ( is_null( $resultPageSet ) ) {
 159                                 $vals = array();
 160                                 if ( $fld_ids ) {
 161                                         $vals['pageid'] = intval( $row->page_id );
 162                                 }
 163                                 if ( $fld_title ) {
 164                                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 165                                         ApiQueryBase::addTitleInfo( $vals, $title );
 166                                 }
 167                                 if ( $fld_sortkey ) {
 168                                         $vals['sortkey'] = $row->cl_sortkey;
 169                                 }
 170                                 if ( $fld_type  ) {
 171                                         $vals['type'] = $row->cl_type;
 172                                 }
 173                                 if ( $fld_timestamp ) {
 174                                         $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $row->cl_timestamp );
 175                                 }
 176                                 $fit = $this->getResult()->addValue( array( 'query', $this->getModuleName() ),
 177                                                 null, $vals );
 178                                 if ( !$fit ) {
 179                                         if ( $params['sort'] == 'timestamp' ) {
 180                                                 $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 181                                         } else {
 182                                                 $this->setContinueEnumParameter( 'continue', $this->getContinueStr( $row, $lastSortKey ) );
 183                                         }
 184                                         break;
 185                                 }
 186                         } else {
 187                                 $resultPageSet->processDbRow( $row );
 188                         }
 189                         $lastSortKey = $row->cl_sortkey; // detect duplicate sortkeys
 190                 }
 191
 192                 if ( is_null( $resultPageSet ) ) {
 193                         $this->getResult()->setIndexedTagName_internal(
 194                                          array( 'query', $this->getModuleName() ), 'cm' );
 195                 }
 196         }
 197
 198         private function getContinueStr( $row, $lastSortKey ) {
 199                 $ret = $row->cl_sortkey . '|';
 200                 if ( $row->cl_sortkey == $lastSortKey ) { // duplicate sort key, add cl_from
 201                         $ret .= $row->cl_from;
 202                 }
 203                 return $ret;
 204         }
 205
 206         /**
 207          * Add DB WHERE clause to continue previous query based on 'continue' parameter
 208          */
 209         private function setContinuation( $continue, $dir ) {
 210                 if ( is_null( $continue ) ) {
 211                         return; // This is not a continuation request
 212                 }
 213
 214                 $pos = strrpos( $continue, '|' );
 215                 $sortkey = substr( $continue, 0, $pos );
 216                 $fromstr = substr( $continue, $pos + 1 );
 217                 $from = intval( $fromstr );
 218
 219                 if ( $from == 0 && strlen( $fromstr ) > 0 ) {
 220                         $this->dieUsage( 'Invalid continue param. You should pass the original value returned by the previous query', 'badcontinue' );
 221                 }
 222
 223                 $encSortKey = $this->getDB()->addQuotes( $sortkey );
 224                 $encFrom = $this->getDB()->addQuotes( $from );
 225
 226                 $op = ( $dir == 'desc' ? '<' : '>' );
 227
 228                 if ( $from != 0 ) {
 229                         // Duplicate sort key continue
 230                         $this->addWhere( "cl_sortkey$op$encSortKey OR (cl_sortkey=$encSortKey AND cl_from$op=$encFrom)" );
 231                 } else {
 232                         $this->addWhere( "cl_sortkey$op=$encSortKey" );
 233                 }
 234         }
 235
 236         public function getAllowedParams() {
 237                 return array(
 238                         'title' => array(
 239                                 ApiBase::PARAM_TYPE => 'string',
 240                         ),
 241                         'pageid' => array(
 242                                 ApiBase::PARAM_TYPE => 'integer'
 243                         ),
 244                         'prop' => array(
 245                                 ApiBase::PARAM_DFLT => 'ids|title',
 246                                 ApiBase::PARAM_ISMULTI => true,
 247                                 ApiBase::PARAM_TYPE => array (
 248                                         'ids',
 249                                         'title',
 250                                         'sortkey',
 251                                         'type',
 252                                         'timestamp',
 253                                 )
 254                         ),
 255                         'namespace' => array (
 256                                 ApiBase::PARAM_ISMULTI => true,
 257                                 ApiBase::PARAM_TYPE => 'namespace',
 258                         ),
 259                         'type' => array(
 260                                 ApiBase::PARAM_ISMULTI => true,
 261                                 ApiBase::PARAM_DFLT => 'page|subcat|file',
 262                                 ApiBase::PARAM_TYPE => array(
 263                                         'page',
 264                                         'subcat',
 265                                         'file'
 266                                 )
 267                         ),
 268                         'continue' => null,
 269                         'limit' => array(
 270                                 ApiBase::PARAM_TYPE => 'limit',
 271                                 ApiBase::PARAM_DFLT => 10,
 272                                 ApiBase::PARAM_MIN => 1,
 273                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 274                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 275                         ),
 276                         'sort' => array(
 277                                 ApiBase::PARAM_DFLT => 'sortkey',
 278                                 ApiBase::PARAM_TYPE => array(
 279                                         'sortkey',
 280                                         'timestamp'
 281                                 )
 282                         ),
 283                         'dir' => array(
 284                                 ApiBase::PARAM_DFLT => 'asc',
 285                                 ApiBase::PARAM_TYPE => array(
 286                                         'asc',
 287                                         'desc'
 288                                 )
 289                         ),
 290                         'start' => array(
 291                                 ApiBase::PARAM_TYPE => 'timestamp'
 292                         ),
 293                         'end' => array(
 294                                 ApiBase::PARAM_TYPE => 'timestamp'
 295                         ),
 296                         'startsortkey' => null,
 297                         'endsortkey' => null,
 298                 );
 299         }
 300
 301         public function getParamDescription() {
 302                 global $wgMiserMode;
 303                 $p = $this->getModulePrefix();
 304                 $desc = array(
 305                         'title' => 'Which category to enumerate (required). Must include Category: prefix. Cannot be used together with cmpageid',
 306                         'pageid' => 'Page ID of the category to enumerate. Cannot be used together with cmtitle',
 307                         'prop' => array(
 308                                 'What pieces of information to include',
 309                                 ' ids        - Adds the page ID',
 310                                 ' title      - Adds the title and namespace ID of the page',
 311                                 ' sortkey    - Adds the sortkey used for the category',
 312                                 ' type       - Adds the type that the page has been categorised as',
 313                                 ' timestamp  - Adds the timestamp of when the page was included',
 314                         ),
 315                         'namespace' => 'Only include pages in these namespaces',
 316                         'type' => 'What type of category members to include',
 317                         'sort' => 'Property to sort by',
 318                         'dir' => 'In which direction to sort',
 319                         'start' => "Timestamp to start listing from. Can only be used with {$p}sort=timestamp",
 320                         'end' => "Timestamp to end listing at. Can only be used with {$p}sort=timestamp",
 321                         'startsortkey' => "Sortkey to start listing from. Can only be used with {$p}sort=sortkey",
 322                         'endsortkey' => "Sortkey to end listing at. Can only be used with {$p}sort=sortkey",
 323                         'continue' => 'For large categories, give the value retured from previous query',
 324                         'limit' => 'The maximum number of pages to return.',
 325                 );
 326                 if ( $wgMiserMode ) {
 327                         $desc['namespace'] = array(
 328                                 $desc['namespace'],
 329                                 'NOTE: Due to $wgMiserMode, using this may result in fewer than "limit" results',
 330                                 'returned before continuing; in extreme cases, zero results may be returned',
 331                         );
 332                 }
 333                 return $desc;
 334         }
 335
 336         public function getDescription() {
 337                 return 'List all pages in a given category';
 338         }
 339
 340         public function getPossibleErrors() {
 341                 return array_merge( parent::getPossibleErrors(), array(
 342                         array( 'code' => 'cmmissingparam', 'info' => 'One of the parameters title, pageid is required' ),
 343                         array( 'code' => 'cminvalidparammix', 'info' => 'The parameters title, pageid can not be used together' ),
 344                         array( 'code' => 'invalidcategory', 'info' => 'The category name you entered is not valid' ),
 345                         array( 'code' => 'badcontinue', 'info' => 'Invalid continue param. You should pass the original value returned by the previous query' ),
 346                         array( 'nosuchpageid', 'pageid' ),
 347                 ) );
 348         }
 349
 350         protected function getExamples() {
 351                 return array(
 352                         'Get first 10 pages in [[Category:Physics]]:',
 353                         '  api.php?action=query&list=categorymembers&cmtitle=Category:Physics',
 354                         'Get page info about first 10 pages in [[Category:Physics]]:',
 355                         '  api.php?action=query&generator=categorymembers&gcmtitle=Category:Physics&prop=info',
 356                 );
 357         }
 358
 359         public function getVersion() {
 360                 return __CLASS__ . ': $Id$';
 361         }
 362 }