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 /**
  28  * A query module to enumerate pages that belong to a category.
  29  *
  30  * @ingroup API
  31  */
  32 class ApiQueryCategoryMembers extends ApiQueryGeneratorBase {
  33
  34         public function __construct( $query, $moduleName ) {
  35                 parent::__construct( $query, $moduleName, 'cm' );
  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 $resultPageSet ApiPageSet
  52          * @return void
  53          */
  54         private function run( $resultPageSet = null ) {
  55                 $params = $this->extractRequestParams();
  56
  57                 $categoryTitle = $this->getTitleOrPageId( $params )->getTitle();
  58                 if ( $categoryTitle->getNamespace() != NS_CATEGORY ) {
  59                         $this->dieUsage( 'The category name you entered is not valid', 'invalidcategory' );
  60                 }
  61
  62                 $prop = array_flip( $params['prop'] );
  63                 $fld_ids = isset( $prop['ids'] );
  64                 $fld_title = isset( $prop['title'] );
  65                 $fld_sortkey = isset( $prop['sortkey'] );
  66                 $fld_sortkeyprefix = isset( $prop['sortkeyprefix'] );
  67                 $fld_timestamp = isset( $prop['timestamp'] );
  68                 $fld_type = isset( $prop['type'] );
  69
  70                 if ( is_null( $resultPageSet ) ) {
  71                         $this->addFields( array( 'cl_from', 'cl_sortkey', 'cl_type', 'page_namespace', 'page_title' ) );
  72                         $this->addFieldsIf( 'page_id', $fld_ids );
  73                         $this->addFieldsIf( 'cl_sortkey_prefix', $fld_sortkeyprefix );
  74                 } else {
  75                         $this->addFields( $resultPageSet->getPageTableFields() ); // will include page_ id, ns, title
  76                         $this->addFields( array( 'cl_from', 'cl_sortkey', 'cl_type' ) );
  77                 }
  78
  79                 $this->addFieldsIf( 'cl_timestamp', $fld_timestamp || $params['sort'] == 'timestamp' );
  80
  81                 $this->addTables( array( 'page', 'categorylinks' ) );   // must be in this order for 'USE INDEX'
  82
  83                 $this->addWhereFld( 'cl_to', $categoryTitle->getDBkey() );
  84                 $queryTypes = $params['type'];
  85                 $contWhere = false;
  86
  87                 // Scanning large datasets for rare categories sucks, and I already told
  88                 // how to have efficient subcategory access :-) ~~~~ (oh well, domas)
  89                 global $wgMiserMode;
  90                 $miser_ns = array();
  91                 if ( $wgMiserMode ) {
  92                         $miser_ns = $params['namespace'];
  93                 } else {
  94                         $this->addWhereFld( 'page_namespace', $params['namespace'] );
  95                 }
  96
  97                 $dir = in_array( $params['dir'], array( 'asc', 'ascending', 'newer' ) ) ? 'newer' : 'older';
  98
  99                 if ( $params['sort'] == 'timestamp' ) {
 100                         $this->addTimestampWhereRange( 'cl_timestamp',
 101                                 $dir,
 102                                 $params['start'],
 103                                 $params['end'] );
 104
 105                         $this->addOption( 'USE INDEX', 'cl_timestamp' );
 106                 } else {
 107                         if ( $params['continue'] ) {
 108                                 $cont = explode( '|', $params['continue'], 3 );
 109                                 if ( count( $cont ) != 3 ) {
 110                                         $this->dieUsage( 'Invalid continue param. You should pass the original value returned '.
 111                                                 'by the previous query', '_badcontinue'
 112                                         );
 113                                 }
 114
 115                                 // Remove the types to skip from $queryTypes
 116                                 $contTypeIndex = array_search( $cont[0], $queryTypes );
 117                                 $queryTypes = array_slice( $queryTypes, $contTypeIndex );
 118
 119                                 // Add a WHERE clause for sortkey and from
 120                                 // pack( "H*", $foo ) is used to convert hex back to binary
 121                                 $escSortkey = $this->getDB()->addQuotes( pack( "H*", $cont[1] ) );
 122                                 $from = intval( $cont[2] );
 123                                 $op = $dir == 'newer' ? '>' : '<';
 124                                 // $contWhere is used further down
 125                                 $contWhere = "cl_sortkey $op $escSortkey OR " .
 126                                         "(cl_sortkey = $escSortkey AND " .
 127                                         "cl_from $op= $from)";
 128                                 // The below produces ORDER BY cl_sortkey, cl_from, possibly with DESC added to each of them
 129                                 $this->addWhereRange( 'cl_sortkey', $dir, null, null );
 130                                 $this->addWhereRange( 'cl_from', $dir, null, null );
 131                         } else {
 132                                 $startsortkey = $params['startsortkeyprefix'] !== null ?
 133                                         Collation::singleton()->getSortkey( $params['startsortkeyprefix'] ) :
 134                                         $params['startsortkey'];
 135                                 $endsortkey = $params['endsortkeyprefix'] !== null ?
 136                                         Collation::singleton()->getSortkey( $params['endsortkeyprefix'] ) :
 137                                         $params['endsortkey'];
 138
 139                                 // The below produces ORDER BY cl_sortkey, cl_from, possibly with DESC added to each of them
 140                                 $this->addWhereRange( 'cl_sortkey',
 141                                         $dir,
 142                                         $startsortkey,
 143                                         $endsortkey );
 144                                 $this->addWhereRange( 'cl_from', $dir, null, null );
 145                         }
 146                         $this->addOption( 'USE INDEX', 'cl_sortkey' );
 147                 }
 148
 149                 $this->addWhere( 'cl_from=page_id' );
 150
 151                 $limit = $params['limit'];
 152                 $this->addOption( 'LIMIT', $limit + 1 );
 153
 154                 if ( $params['sort'] == 'sortkey' ) {
 155                         // Run a separate SELECT query for each value of cl_type.
 156                         // This is needed because cl_type is an enum, and MySQL has
 157                         // inconsistencies between ORDER BY cl_type and
 158                         // WHERE cl_type >= 'foo' making proper paging impossible
 159                         // and unindexed.
 160                         $rows = array();
 161                         $first = true;
 162                         foreach ( $queryTypes as $type ) {
 163                                 $extraConds = array( 'cl_type' => $type );
 164                                 if ( $first && $contWhere ) {
 165                                         // Continuation condition. Only added to the
 166                                         // first query, otherwise we'll skip things
 167                                         $extraConds[] = $contWhere;
 168                                 }
 169                                 $res = $this->select( __METHOD__, array( 'where' => $extraConds ) );
 170                                 $rows = array_merge( $rows, iterator_to_array( $res ) );
 171                                 if ( count( $rows ) >= $limit + 1 ) {
 172                                         break;
 173                                 }
 174                                 $first = false;
 175                         }
 176                 } else {
 177                         // Sorting by timestamp
 178                         // No need to worry about per-type queries because we
 179                         // aren't sorting or filtering by type anyway
 180                         $res = $this->select( __METHOD__ );
 181                         $rows = iterator_to_array( $res );
 182                 }
 183
 184                 $result = $this->getResult();
 185                 $count = 0;
 186                 foreach ( $rows as $row ) {
 187                         if ( ++ $count > $limit ) {
 188                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 189                                 // TODO: Security issue - if the user has no right to view next title, it will still be shown
 190                                 if ( $params['sort'] == 'timestamp' ) {
 191                                         $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 192                                 } else {
 193                                         $sortkey = bin2hex( $row->cl_sortkey );
 194                                         $this->setContinueEnumParameter( 'continue',
 195                                                 "{$row->cl_type}|$sortkey|{$row->cl_from}"
 196                                         );
 197                                 }
 198                                 break;
 199                         }
 200
 201                         // Since domas won't tell anyone what he told long ago, apply
 202                         // cmnamespace here. This means the query may return 0 actual
 203                         // results, but on the other hand it could save returning 5000
 204                         // useless results to the client. ~~~~
 205                         if ( count( $miser_ns ) && !in_array( $row->page_namespace, $miser_ns ) ) {
 206                                 continue;
 207                         }
 208
 209                         if ( is_null( $resultPageSet ) ) {
 210                                 $vals = array();
 211                                 if ( $fld_ids ) {
 212                                         $vals['pageid'] = intval( $row->page_id );
 213                                 }
 214                                 if ( $fld_title ) {
 215                                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 216                                         ApiQueryBase::addTitleInfo( $vals, $title );
 217                                 }
 218                                 if ( $fld_sortkey ) {
 219                                         $vals['sortkey'] = bin2hex( $row->cl_sortkey );
 220                                 }
 221                                 if ( $fld_sortkeyprefix ) {
 222                                         $vals['sortkeyprefix'] = $row->cl_sortkey_prefix;
 223                                 }
 224                                 if ( $fld_type  ) {
 225                                         $vals['type'] = $row->cl_type;
 226                                 }
 227                                 if ( $fld_timestamp ) {
 228                                         $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $row->cl_timestamp );
 229                                 }
 230                                 $fit = $result->addValue( array( 'query', $this->getModuleName() ),
 231                                                 null, $vals );
 232                                 if ( !$fit ) {
 233                                         if ( $params['sort'] == 'timestamp' ) {
 234                                                 $this->setContinueEnumParameter( 'start', wfTimestamp( TS_ISO_8601, $row->cl_timestamp ) );
 235                                         } else {
 236                                                 $sortkey = bin2hex( $row->cl_sortkey );
 237                                                 $this->setContinueEnumParameter( 'continue',
 238                                                         "{$row->cl_type}|$sortkey|{$row->cl_from}"
 239                                                 );
 240                                         }
 241                                         break;
 242                                 }
 243                         } else {
 244                                 $resultPageSet->processDbRow( $row );
 245                         }
 246                 }
 247
 248                 if ( is_null( $resultPageSet ) ) {
 249                         $result->setIndexedTagName_internal(
 250                                          array( 'query', $this->getModuleName() ), 'cm' );
 251                 }
 252         }
 253
 254         public function getAllowedParams() {
 255                 return array(
 256                         'title' => array(
 257                                 ApiBase::PARAM_TYPE => 'string',
 258                         ),
 259                         'pageid' => array(
 260                                 ApiBase::PARAM_TYPE => 'integer'
 261                         ),
 262                         'prop' => array(
 263                                 ApiBase::PARAM_DFLT => 'ids|title',
 264                                 ApiBase::PARAM_ISMULTI => true,
 265                                 ApiBase::PARAM_TYPE => array (
 266                                         'ids',
 267                                         'title',
 268                                         'sortkey',
 269                                         'sortkeyprefix',
 270                                         'type',
 271                                         'timestamp',
 272                                 )
 273                         ),
 274                         'namespace' => array (
 275                                 ApiBase::PARAM_ISMULTI => true,
 276                                 ApiBase::PARAM_TYPE => 'namespace',
 277                         ),
 278                         'type' => array(
 279                                 ApiBase::PARAM_ISMULTI => true,
 280                                 ApiBase::PARAM_DFLT => 'page|subcat|file',
 281                                 ApiBase::PARAM_TYPE => array(
 282                                         'page',
 283                                         'subcat',
 284                                         'file'
 285                                 )
 286                         ),
 287                         'continue' => null,
 288                         'limit' => array(
 289                                 ApiBase::PARAM_TYPE => 'limit',
 290                                 ApiBase::PARAM_DFLT => 10,
 291                                 ApiBase::PARAM_MIN => 1,
 292                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 293                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 294                         ),
 295                         'sort' => array(
 296                                 ApiBase::PARAM_DFLT => 'sortkey',
 297                                 ApiBase::PARAM_TYPE => array(
 298                                         'sortkey',
 299                                         'timestamp'
 300                                 )
 301                         ),
 302                         'dir' => array(
 303                                 ApiBase::PARAM_DFLT => 'ascending',
 304                                 ApiBase::PARAM_TYPE => array(
 305                                         'asc',
 306                                         'desc',
 307                                         // Normalising with other modules
 308                                         'ascending',
 309                                         'descending',
 310                                         'newer',
 311                                         'older',
 312                                 )
 313                         ),
 314                         'start' => array(
 315                                 ApiBase::PARAM_TYPE => 'timestamp'
 316                         ),
 317                         'end' => array(
 318                                 ApiBase::PARAM_TYPE => 'timestamp'
 319                         ),
 320                         'startsortkey' => null,
 321                         'endsortkey' => null,
 322                         'startsortkeyprefix' => null,
 323                         'endsortkeyprefix' => null,
 324                 );
 325         }
 326
 327         public function getParamDescription() {
 328                 global $wgMiserMode;
 329                 $p = $this->getModulePrefix();
 330                 $desc = array(
 331                         'title' => "Which category to enumerate (required). Must include Category: prefix. Cannot be used together with {$p}pageid",
 332                         'pageid' => "Page ID of the category to enumerate. Cannot be used together with {$p}title",
 333                         'prop' => array(
 334                                 'What pieces of information to include',
 335                                 ' ids           - Adds the page ID',
 336                                 ' title         - Adds the title and namespace ID of the page',
 337                                 ' sortkey       - Adds the sortkey used for sorting in the category (hexadecimal string)',
 338                                 ' sortkeyprefix - Adds the sortkey prefix used for sorting in the category (human-readable part of the sortkey)',
 339                                 ' type          - Adds the type that the page has been categorised as (page, subcat or file)',
 340                                 ' timestamp     - Adds the timestamp of when the page was included',
 341                         ),
 342                         'namespace' => 'Only include pages in these namespaces',
 343                         'type' => "What type of category members to include. Ignored when {$p}sort=timestamp is set",
 344                         'sort' => 'Property to sort by',
 345                         'dir' => 'In which direction to sort',
 346                         'start' => "Timestamp to start listing from. Can only be used with {$p}sort=timestamp",
 347                         'end' => "Timestamp to end listing at. Can only be used with {$p}sort=timestamp",
 348                         'startsortkey' => "Sortkey to start listing from. Must be given in binary format. Can only be used with {$p}sort=sortkey",
 349                         'endsortkey' => "Sortkey to end listing at. Must be given in binary format. Can only be used with {$p}sort=sortkey",
 350                         'startsortkeyprefix' => "Sortkey prefix to start listing from. Can only be used with {$p}sort=sortkey. Overrides {$p}startsortkey",
 351                         'endsortkeyprefix' => "Sortkey prefix to end listing BEFORE (not at, if this value occurs it will not be included!). Can only be used with {$p}sort=sortkey. Overrides {$p}endsortkey",
 352                         'continue' => 'For large categories, give the value returned from previous query',
 353                         'limit' => 'The maximum number of pages to return.',
 354                 );
 355
 356                 if ( $wgMiserMode ) {
 357                         $desc['namespace'] = array(
 358                                 $desc['namespace'],
 359                                 "NOTE: Due to \$wgMiserMode, using this may result in fewer than \"{$p}limit\" results",
 360                                 'returned before continuing; in extreme cases, zero results may be returned.',
 361                                 "Note that you can use {$p}type=subcat or {$p}type=file instead of {$p}namespace=14 or 6.",
 362                         );
 363                 }
 364                 return $desc;
 365         }
 366
 367         public function getResultProperties() {
 368                 return array(
 369                         'ids' => array(
 370                                 'pageid' => 'integer'
 371                         ),
 372                         'title' => array(
 373                                 'ns' => 'namespace',
 374                                 'title' => 'string'
 375                         ),
 376                         'sortkey' => array(
 377                                 'sortkey' => 'string'
 378                         ),
 379                         'sortkeyprefix' => array(
 380                                 'sortkeyprefix' => 'string'
 381                         ),
 382                         'type' => array(
 383                                 'type' => array(
 384                                         ApiBase::PROP_TYPE => array(
 385                                                 'page',
 386                                                 'subcat',
 387                                                 'file'
 388                                         )
 389                                 )
 390                         ),
 391                         'timestamp' => array(
 392                                 'timestamp' => 'timestamp'
 393                         )
 394                 );
 395         }
 396
 397         public function getDescription() {
 398                 return 'List all pages in a given category';
 399         }
 400
 401         public function getPossibleErrors() {
 402                 return array_merge( parent::getPossibleErrors(),
 403                         $this->getTitleOrPageIdErrorMessage(),
 404                         array(
 405                                 array( 'code' => 'invalidcategory', 'info' => 'The category name you entered is not valid' ),
 406                                 array( 'code' => 'badcontinue', 'info' => 'Invalid continue param. You should pass the original value returned by the previous query' ),
 407                         )
 408                 );
 409         }
 410
 411         public function getExamples() {
 412                 return array(
 413                         'api.php?action=query&list=categorymembers&cmtitle=Category:Physics' => 'Get first 10 pages in [[Category:Physics]]',
 414                         'api.php?action=query&generator=categorymembers&gcmtitle=Category:Physics&prop=info' => 'Get page info about first 10 pages in [[Category:Physics]]',
 415                 );
 416         }
 417
 418         public function getHelpUrls() {
 419                 return 'https://www.mediawiki.org/wiki/API:Categorymembers';
 420         }
 421
 422         public function getVersion() {
 423                 return __CLASS__ . ': $Id$';
 424         }
 425 }