includes/api/ApiQueryRevisions.php

   1 <?php
   2
   3 /*
   4  * Created on Sep 7, 2006
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License along
  21  * with this program; if not, write to the Free Software Foundation, Inc.,
  22  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  * http://www.gnu.org/copyleft/gpl.html
  24  */
  25
  26 if ( !defined( 'MEDIAWIKI' ) ) {
  27         // Eclipse helper - will be ignored in production
  28         require_once ( 'ApiQueryBase.php' );
  29 }
  30
  31 /**
  32  * A query action to enumerate revisions of a given page, or show top revisions of multiple pages.
  33  * Various pieces of information may be shown - flags, comments, and the actual wiki markup of the rev.
  34  * In the enumeration mode, ranges of revisions may be requested and filtered.
  35  *
  36  * @ingroup API
  37  */
  38 class ApiQueryRevisions extends ApiQueryBase {
  39
  40         public function __construct( $query, $moduleName ) {
  41                 parent :: __construct( $query, $moduleName, 'rv' );
  42         }
  43
  44         private $fld_ids = false, $fld_flags = false, $fld_timestamp = false, $fld_size = false,
  45                         $fld_comment = false, $fld_parsedcomment = false, $fld_user = false, $fld_content = false, $fld_tags = false;
  46
  47         protected function getTokenFunctions() {
  48                 // tokenname => function
  49                 // function prototype is func($pageid, $title, $rev)
  50                 // should return token or false
  51
  52                 // Don't call the hooks twice
  53                 if ( isset( $this->tokenFunctions ) )
  54                         return $this->tokenFunctions;
  55
  56                 // If we're in JSON callback mode, no tokens can be obtained
  57                 if ( !is_null( $this->getMain()->getRequest()->getVal( 'callback' ) ) )
  58                         return array();
  59
  60                 $this->tokenFunctions = array(
  61                         'rollback' => array( 'ApiQueryRevisions', 'getRollbackToken' )
  62                 );
  63                 wfRunHooks( 'APIQueryRevisionsTokens', array( &$this->tokenFunctions ) );
  64                 return $this->tokenFunctions;
  65         }
  66
  67         public static function getRollbackToken( $pageid, $title, $rev )
  68         {
  69                 global $wgUser;
  70                 if ( !$wgUser->isAllowed( 'rollback' ) )
  71                         return false;
  72                 return $wgUser->editToken( array( $title->getPrefixedText(),
  73                                                 $rev->getUserText() ) );
  74         }
  75
  76         public function execute() {
  77                 $params = $this->extractRequestParams( false );
  78
  79                 // If any of those parameters are used, work in 'enumeration' mode.
  80                 // Enum mode can only be used when exactly one page is provided.
  81                 // Enumerating revisions on multiple pages make it extremely
  82                 // difficult to manage continuations and require additional SQL indexes
  83                 $enumRevMode = ( !is_null( $params['user'] ) || !is_null( $params['excludeuser'] ) ||
  84                                 !is_null( $params['limit'] ) || !is_null( $params['startid'] ) ||
  85                                 !is_null( $params['endid'] ) || $params['dir'] === 'newer' ||
  86                                 !is_null( $params['start'] ) || !is_null( $params['end'] ) );
  87
  88
  89                 $pageSet = $this->getPageSet();
  90                 $pageCount = $pageSet->getGoodTitleCount();
  91                 $revCount = $pageSet->getRevisionCount();
  92
  93                 // Optimization -- nothing to do
  94                 if ( $revCount === 0 && $pageCount === 0 )
  95                         return;
  96
  97                 if ( $revCount > 0 && $enumRevMode )
  98                         $this->dieUsage( 'The revids= parameter may not be used with the list options (limit, startid, endid, dirNewer, start, end).', 'revids' );
  99
 100                 if ( $pageCount > 1 && $enumRevMode )
 101                         $this->dieUsage( 'titles, pageids or a generator was used to supply multiple pages, but the limit, startid, endid, dirNewer, user, excludeuser, start and end parameters may only be used on a single page.', 'multpages' );
 102
 103                 $this->diffto = $this->difftotext = null;
 104                 if ( !is_null( $params['difftotext'] ) ) {
 105                         $this->difftotext = $params['difftotext'];
 106                 } else if ( !is_null( $params['diffto'] ) ) {
 107                         if ( $params['diffto'] == 'cur' )
 108                                 $params['diffto'] = 0;
 109                         if ( ( !ctype_digit( $params['diffto'] ) || $params['diffto'] < 0 )
 110                                         && $params['diffto'] != 'prev' && $params['diffto'] != 'next' )
 111                                 $this->dieUsage( 'rvdiffto must be set to a non-negative number, "prev", "next" or "cur"', 'diffto' );
 112                         // Check whether the revision exists and is readable,
 113                         // DifferenceEngine returns a rather ambiguous empty
 114                         // string if that's not the case
 115                         if ( $params['diffto'] != 0 ) {
 116                                 $difftoRev = Revision::newFromID( $params['diffto'] );
 117                                 if ( !$difftoRev )
 118                                         $this->dieUsageMsg( array( 'nosuchrevid', $params['diffto'] ) );
 119                                 if ( !$difftoRev->userCan( Revision::DELETED_TEXT ) ) {
 120                                         $this->setWarning( "Couldn't diff to r{$difftoRev->getID()}: content is hidden" );
 121                                         $params['diffto'] = null;
 122                                 }
 123                         }
 124                         $this->diffto = $params['diffto'];
 125                 }
 126
 127                 $db = $this->getDB();
 128                 $this->addTables( array( 'page', 'revision' ) );
 129                 $this->addFields( Revision::selectFields() );
 130                 $this->addWhere( 'page_id = rev_page' );
 131
 132                 $prop = array_flip( $params['prop'] );
 133
 134                 // Optional fields
 135                 $this->fld_ids = isset ( $prop['ids'] );
 136                 // $this->addFieldsIf('rev_text_id', $this->fld_ids); // should this be exposed?
 137                 $this->fld_flags = isset ( $prop['flags'] );
 138                 $this->fld_timestamp = isset ( $prop['timestamp'] );
 139                 $this->fld_comment = isset ( $prop['comment'] );
 140                 $this->fld_parsedcomment = isset ( $prop['parsedcomment'] );
 141                 $this->fld_size = isset ( $prop['size'] );
 142                 $this->fld_user = isset ( $prop['user'] );
 143                 $this->token = $params['token'];
 144
 145                 // Possible indexes used
 146                 $index = array();
 147
 148                 if ( !is_null( $this->token ) || $pageCount > 0 ) {
 149                         $this->addFields( Revision::selectPageFields() );
 150                 }
 151
 152                 if ( isset ( $prop['tags'] ) ) {
 153                         $this->fld_tags = true;
 154                         $this->addTables( 'tag_summary' );
 155                         $this->addJoinConds( array( 'tag_summary' => array( 'LEFT JOIN', array( 'rev_id=ts_rev_id' ) ) ) );
 156                         $this->addFields( 'ts_tags' );
 157                 }
 158
 159                 if ( !is_null( $params['tag'] ) ) {
 160                         $this->addTables( 'change_tag' );
 161                         $this->addJoinConds( array( 'change_tag' => array( 'INNER JOIN', array( 'rev_id=ct_rev_id' ) ) ) );
 162                         $this->addWhereFld( 'ct_tag' , $params['tag'] );
 163                         global $wgOldChangeTagsIndex;
 164                         $index['change_tag'] = $wgOldChangeTagsIndex ?  'ct_tag' : 'change_tag_tag_id';
 165                 }
 166
 167                 if ( isset( $prop['content'] ) || !is_null( $this->difftotext ) ) {
 168
 169                         // For each page we will request, the user must have read rights for that page
 170                         foreach ( $pageSet->getGoodTitles() as $title ) {
 171                                 if ( !$title->userCanRead() )
 172                                         $this->dieUsage(
 173                                                 'The current user is not allowed to read ' . $title->getPrefixedText(),
 174                                                 'accessdenied' );
 175                         }
 176
 177                         $this->addTables( 'text' );
 178                         $this->addWhere( 'rev_text_id=old_id' );
 179                         $this->addFields( 'old_id' );
 180                         $this->addFields( Revision::selectTextFields() );
 181
 182                         $this->fld_content = isset( $prop['content'] );
 183
 184                         $this->expandTemplates = $params['expandtemplates'];
 185                         $this->generateXML = $params['generatexml'];
 186                         if ( isset( $params['section'] ) )
 187                                 $this->section = $params['section'];
 188                         else
 189                                 $this->section = false;
 190                 }
 191
 192                 $userMax = ( $this->fld_content ? ApiBase::LIMIT_SML1 : ApiBase::LIMIT_BIG1 );
 193                 $botMax  = ( $this->fld_content ? ApiBase::LIMIT_SML2 : ApiBase::LIMIT_BIG2 );
 194                 $limit = $params['limit'];
 195                 if ( $limit == 'max' ) {
 196                         $limit = $this->getMain()->canApiHighLimits() ? $botMax : $userMax;
 197                         $this->getResult()->addValue( 'limits', $this->getModuleName(), $limit );
 198                 }
 199
 200                 if ( $enumRevMode ) {
 201
 202                         // This is mostly to prevent parameter errors (and optimize SQL?)
 203                         if ( !is_null( $params['startid'] ) && !is_null( $params['start'] ) )
 204                                 $this->dieUsage( 'start and startid cannot be used together', 'badparams' );
 205
 206                         if ( !is_null( $params['endid'] ) && !is_null( $params['end'] ) )
 207                                 $this->dieUsage( 'end and endid cannot be used together', 'badparams' );
 208
 209                         if ( !is_null( $params['user'] ) && !is_null( $params['excludeuser'] ) )
 210                                 $this->dieUsage( 'user and excludeuser cannot be used together', 'badparams' );
 211
 212                         // This code makes an assumption that sorting by rev_id and rev_timestamp produces
 213                         // the same result. This way users may request revisions starting at a given time,
 214                         // but to page through results use the rev_id returned after each page.
 215                         // Switching to rev_id removes the potential problem of having more than
 216                         // one row with the same timestamp for the same page.
 217                         // The order needs to be the same as start parameter to avoid SQL filesort.
 218
 219                         if ( is_null( $params['startid'] ) && is_null( $params['endid'] ) )
 220                                 $this->addWhereRange( 'rev_timestamp', $params['dir'],
 221                                         $params['start'], $params['end'] );
 222                         else {
 223                                 $this->addWhereRange( 'rev_id', $params['dir'],
 224                                         $params['startid'], $params['endid'] );
 225                                 // One of start and end can be set
 226                                 // If neither is set, this does nothing
 227                                 $this->addWhereRange( 'rev_timestamp', $params['dir'],
 228                                         $params['start'], $params['end'], false );
 229                         }
 230
 231                         // must manually initialize unset limit
 232                         if ( is_null( $limit ) )
 233                                 $limit = 10;
 234                         $this->validateLimit( 'limit', $limit, 1, $userMax, $botMax );
 235
 236                         // There is only one ID, use it
 237                         $ids = array_keys( $pageSet->getGoodTitles() );
 238                         $this->addWhereFld( 'rev_page', reset( $ids ) );
 239
 240                         if ( !is_null( $params['user'] ) ) {
 241                                 $this->addWhereFld( 'rev_user_text', $params['user'] );
 242                         } elseif ( !is_null( $params['excludeuser'] ) ) {
 243                                 $this->addWhere( 'rev_user_text != ' .
 244                                         $db->addQuotes( $params['excludeuser'] ) );
 245                         }
 246                         if ( !is_null( $params['user'] ) || !is_null( $params['excludeuser'] ) ) {
 247                                 // Paranoia: avoid brute force searches (bug 17342)
 248                                 $this->addWhere( $db->bitAnd( 'rev_deleted', Revision::DELETED_USER ) . ' = 0' );
 249                         }
 250                 }
 251                 elseif ( $revCount > 0 ) {
 252                         $max = $this->getMain()->canApiHighLimits() ? $botMax : $userMax;
 253                         $revs = $pageSet->getRevisionIDs();
 254                         if ( self::truncateArray( $revs, $max ) )
 255                                 $this->setWarning( "Too many values supplied for parameter 'revids': the limit is $max" );
 256
 257                         // Get all revision IDs
 258                         $this->addWhereFld( 'rev_id', array_keys( $revs ) );
 259
 260                         if ( !is_null( $params['continue'] ) )
 261                                 $this->addWhere( "rev_id >= '" . intval( $params['continue'] ) . "'" );
 262                         $this->addOption( 'ORDER BY', 'rev_id' );
 263
 264                         // assumption testing -- we should never get more then $revCount rows.
 265                         $limit = $revCount;
 266                 }
 267                 elseif ( $pageCount > 0 ) {
 268                         $max = $this->getMain()->canApiHighLimits() ? $botMax : $userMax;
 269                         $titles = $pageSet->getGoodTitles();
 270                         if ( self::truncateArray( $titles, $max ) )
 271                                 $this->setWarning( "Too many values supplied for parameter 'titles': the limit is $max" );
 272
 273                         // When working in multi-page non-enumeration mode,
 274                         // limit to the latest revision only
 275                         $this->addWhere( 'page_id=rev_page' );
 276                         $this->addWhere( 'page_latest=rev_id' );
 277
 278                         // Get all page IDs
 279                         $this->addWhereFld( 'page_id', array_keys( $titles ) );
 280                         // Every time someone relies on equality propagation, god kills a kitten :)
 281                         $this->addWhereFld( 'rev_page', array_keys( $titles ) );
 282
 283                         if ( !is_null( $params['continue'] ) )
 284                         {
 285                                 $cont = explode( '|', $params['continue'] );
 286                                 if ( count( $cont ) != 2 )
 287                                         $this->dieUsage( "Invalid continue param. You should pass the original " .
 288                                                         "value returned by the previous query", "_badcontinue" );
 289                                 $pageid = intval( $cont[0] );
 290                                 $revid = intval( $cont[1] );
 291                                 $this->addWhere( "rev_page > '$pageid' OR " .
 292                                                 "(rev_page = '$pageid' AND " .
 293                                                 "rev_id >= '$revid')" );
 294                         }
 295                         $this->addOption( 'ORDER BY', 'rev_page, rev_id' );
 296
 297                         // assumption testing -- we should never get more then $pageCount rows.
 298                         $limit = $pageCount;
 299                 } else
 300                         ApiBase :: dieDebug( __METHOD__, 'param validation?' );
 301
 302                 $this->addOption( 'LIMIT', $limit + 1 );
 303                 $this->addOption( 'USE INDEX', $index );
 304
 305                 $data = array ();
 306                 $count = 0;
 307                 $res = $this->select( __METHOD__ );
 308
 309                 while ( $row = $db->fetchObject( $res ) ) {
 310
 311                         if ( ++ $count > $limit ) {
 312                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 313                                 if ( !$enumRevMode )
 314                                         ApiBase :: dieDebug( __METHOD__, 'Got more rows then expected' ); // bug report
 315                                 $this->setContinueEnumParameter( 'startid', intval( $row->rev_id ) );
 316                                 break;
 317                         }
 318
 319                         //
 320                         $fit = $this->addPageSubItem( $row->rev_page, $this->extractRowInfo( $row ), 'rev' );
 321                         if ( !$fit )
 322                         {
 323                                 if ( $enumRevMode )
 324                                         $this->setContinueEnumParameter( 'startid', intval( $row->rev_id ) );
 325                                 else if ( $revCount > 0 )
 326                                         $this->setContinueEnumParameter( 'continue', intval( $row->rev_id ) );
 327                                 else
 328                                         $this->setContinueEnumParameter( 'continue', intval( $row->rev_page ) .
 329                                                 '|' . intval( $row->rev_id ) );
 330                                 break;
 331                         }
 332                 }
 333                 $db->freeResult( $res );
 334         }
 335
 336         private function extractRowInfo( $row ) {
 337                 $revision = new Revision( $row );
 338                 $title = $revision->getTitle();
 339                 $vals = array ();
 340
 341                 if ( $this->fld_ids ) {
 342                         $vals['revid'] = intval( $revision->getId() );
 343                         // $vals['oldid'] = intval($row->rev_text_id);  // todo: should this be exposed?
 344                         if ( !is_null( $revision->getParentId() ) )
 345                                 $vals['parentid'] = intval( $revision->getParentId() );
 346                 }
 347
 348                 if ( $this->fld_flags && $revision->isMinor() )
 349                         $vals['minor'] = '';
 350
 351                 if ( $this->fld_user ) {
 352                         if ( $revision->isDeleted( Revision::DELETED_USER ) ) {
 353                                 $vals['userhidden'] = '';
 354                         } else {
 355                                 $vals['user'] = $revision->getUserText();
 356                                 if ( !$revision->getUser() )
 357                                         $vals['anon'] = '';
 358                         }
 359                 }
 360
 361                 if ( $this->fld_timestamp ) {
 362                         $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $revision->getTimestamp() );
 363                 }
 364
 365                 if ( $this->fld_size && !is_null( $revision->getSize() ) ) {
 366                         $vals['size'] = intval( $revision->getSize() );
 367                 }
 368
 369                 if ( $this->fld_comment || $this->fld_parsedcomment ) {
 370                         if ( $revision->isDeleted( Revision::DELETED_COMMENT ) ) {
 371                                 $vals['commenthidden'] = '';
 372                         } else {
 373                                 $comment = $revision->getComment();
 374                                 if ( strval( $comment ) !== '' )
 375                                 {
 376                                         if ( $this->fld_comment )
 377                                                 $vals['comment'] = $comment;
 378
 379                                         if ( $this->fld_parsedcomment ) {
 380                                                 global $wgUser;
 381                                                 $vals['parsedcomment'] = $wgUser->getSkin()->formatComment( $comment, $title );
 382                                         }
 383                                 }
 384                         }
 385                 }
 386
 387                 if ( $this->fld_tags ) {
 388                         if ( $row->ts_tags ) {
 389                                 $tags = explode( ',', $row->ts_tags );
 390                                 $this->getResult()->setIndexedTagName( $tags, 'tag' );
 391                                 $vals['tags'] = $tags;
 392                         } else {
 393                                 $vals['tags'] = array();
 394                         }
 395                 }
 396
 397                 if ( !is_null( $this->token ) )
 398                 {
 399                         $tokenFunctions = $this->getTokenFunctions();
 400                         foreach ( $this->token as $t )
 401                         {
 402                                 $val = call_user_func( $tokenFunctions[$t], $title->getArticleID(), $title, $revision );
 403                                 if ( $val === false )
 404                                         $this->setWarning( "Action '$t' is not allowed for the current user" );
 405                                 else
 406                                         $vals[$t . 'token'] = $val;
 407                         }
 408                 }
 409
 410                 $text = null;
 411                 if ( $this->fld_content || !is_null( $this->difftotext ) ) {
 412                         global $wgParser;
 413                         $text = $revision->getText();
 414                         // Expand templates after getting section content because
 415                         // template-added sections don't count and Parser::preprocess()
 416                         // will have less input
 417                         if ( $this->section !== false ) {
 418                                 $text = $wgParser->getSection( $text, $this->section, false );
 419                                 if ( $text === false )
 420                                         $this->dieUsage( "There is no section {$this->section} in r" . $revision->getId(), 'nosuchsection' );
 421                         }
 422                 }
 423                 if ( $this->fld_content && !$revision->isDeleted( Revision::DELETED_TEXT ) ) {
 424                         if ( $this->generateXML ) {
 425                                 $wgParser->startExternalParse( $title, new ParserOptions(), OT_PREPROCESS );
 426                                 $dom = $wgParser->preprocessToDom( $text );
 427                                 if ( is_callable( array( $dom, 'saveXML' ) ) ) {
 428                                         $xml = $dom->saveXML();
 429                                 } else {
 430                                         $xml = $dom->__toString();
 431                                 }
 432                                 $vals['parsetree'] = $xml;
 433
 434                         }
 435                         if ( $this->expandTemplates ) {
 436                                 $text = $wgParser->preprocess( $text, $title, new ParserOptions() );
 437                         }
 438                         ApiResult :: setContent( $vals, $text );
 439                 } else if ( $this->fld_content ) {
 440                         $vals['texthidden'] = '';
 441                 }
 442
 443                 if ( !is_null( $this->diffto ) || !is_null( $this->difftotext ) ) {
 444                         global $wgAPIMaxUncachedDiffs;
 445                         static $n = 0; // Number of uncached diffs we've had
 446                         if ( $n < $wgAPIMaxUncachedDiffs ) {
 447                                 $vals['diff'] = array();
 448                                 if ( !is_null( $this->difftotext ) ) {
 449                                         $engine = new DifferenceEngine( $title );
 450                                         $engine->setText( $text, $this->difftotext );
 451                                 } else {
 452                                         $engine = new DifferenceEngine( $title, $revision->getID(), $this->diffto );
 453                                         $vals['diff']['from'] = $engine->getOldid();
 454                                         $vals['diff']['to'] = $engine->getNewid();
 455                                 }
 456                                 $difftext = $engine->getDiffBody();
 457                                 ApiResult::setContent( $vals['diff'], $difftext );
 458                                 if ( !$engine->wasCacheHit() )
 459                                         $n++;
 460                         } else {
 461                                 $vals['diff']['notcached'] = '';
 462                         }
 463                 }
 464                 return $vals;
 465         }
 466
 467         public function getAllowedParams() {
 468                 return array (
 469                         'prop' => array (
 470                                 ApiBase :: PARAM_ISMULTI => true,
 471                                 ApiBase :: PARAM_DFLT => 'ids|timestamp|flags|comment|user',
 472                                 ApiBase :: PARAM_TYPE => array (
 473                                         'ids',
 474                                         'flags',
 475                                         'timestamp',
 476                                         'user',
 477                                         'size',
 478                                         'comment',
 479                                         'parsedcomment',
 480                                         'content',
 481                                         'tags'
 482                                 )
 483                         ),
 484                         'limit' => array (
 485                                 ApiBase :: PARAM_TYPE => 'limit',
 486                                 ApiBase :: PARAM_MIN => 1,
 487                                 ApiBase :: PARAM_MAX => ApiBase :: LIMIT_BIG1,
 488                                 ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
 489                         ),
 490                         'startid' => array (
 491                                 ApiBase :: PARAM_TYPE => 'integer'
 492                         ),
 493                         'endid' => array (
 494                                 ApiBase :: PARAM_TYPE => 'integer'
 495                         ),
 496                         'start' => array (
 497                                 ApiBase :: PARAM_TYPE => 'timestamp'
 498                         ),
 499                         'end' => array (
 500                                 ApiBase :: PARAM_TYPE => 'timestamp'
 501                         ),
 502                         'dir' => array (
 503                                 ApiBase :: PARAM_DFLT => 'older',
 504                                 ApiBase :: PARAM_TYPE => array (
 505                                         'newer',
 506                                         'older'
 507                                 )
 508                         ),
 509                         'user' => array(
 510                                 ApiBase :: PARAM_TYPE => 'user'
 511                         ),
 512                         'excludeuser' => array(
 513                                 ApiBase :: PARAM_TYPE => 'user'
 514                         ),
 515                         'tag' => null,
 516                         'expandtemplates' => false,
 517                         'generatexml' => false,
 518                         'section' => null,
 519                         'token' => array(
 520                                 ApiBase :: PARAM_TYPE => array_keys( $this->getTokenFunctions() ),
 521                                 ApiBase :: PARAM_ISMULTI => true
 522                         ),
 523                         'continue' => null,
 524                         'diffto' => null,
 525                         'difftotext' => null,
 526                 );
 527         }
 528
 529         public function getParamDescription() {
 530                 return array (
 531                         'prop' => 'Which properties to get for each revision.',
 532                         'limit' => 'Limit how many revisions will be returned (enum)',
 533                         'startid' => 'From which revision id to start enumeration (enum)',
 534                         'endid' => 'Stop revision enumeration on this revid (enum)',
 535                         'start' => 'From which revision timestamp to start enumeration (enum)',
 536                         'end' => 'Enumerate up to this timestamp (enum)',
 537                         'dir' => 'Direction of enumeration - towards "newer" or "older" revisions (enum)',
 538                         'user' => 'Only include revisions made by user',
 539                         'excludeuser' => 'Exclude revisions made by user',
 540                         'expandtemplates' => 'Expand templates in revision content',
 541                         'generatexml' => 'Generate XML parse tree for revision content',
 542                         'section' => 'Only retrieve the content of this section',
 543                         'token' => 'Which tokens to obtain for each revision',
 544                         'continue' => 'When more results are available, use this to continue',
 545                         'diffto' => array( 'Revision ID to diff each revision to.',
 546                                 'Use "prev", "next" and "cur" for the previous, next and current revision respectively.' ),
 547                         'difftotext' => array( 'Text to diff each revision to. Only diffs a limited number of revisions.',
 548                                 'Overrides diffto. If rvsection is set, only that section will be diffed against this text.' ),
 549                         'tag' => 'Only list revisions tagged with this tag',
 550                 );
 551         }
 552
 553         public function getDescription() {
 554                 return array (
 555                         'Get revision information.',
 556                         'This module may be used in several ways:',
 557                         ' 1) Get data about a set of pages (last revision), by setting titles or pageids parameter.',
 558                         ' 2) Get revisions for one given page, by using titles/pageids with start/end/limit params.',
 559                         ' 3) Get data about a set of revisions by setting their IDs with revids parameter.',
 560                         'All parameters marked as (enum) may only be used with a single page (#2).'
 561                 );
 562         }
 563
 564     public function getPossibleErrors() {
 565                 return array_merge( parent::getPossibleErrors(), array(
 566                         array( 'nosuchrevid', 'diffto' ),
 567         ) );
 568         }
 569
 570         protected function getExamples() {
 571                 return array (
 572                         'Get data with content for the last revision of titles "API" and "Main Page":',
 573                         '  api.php?action=query&prop=revisions&titles=API|Main%20Page&rvprop=timestamp|user|comment|content',
 574                         'Get last 5 revisions of the "Main Page":',
 575                         '  api.php?action=query&prop=revisions&titles=Main%20Page&rvlimit=5&rvprop=timestamp|user|comment',
 576                         'Get first 5 revisions of the "Main Page":',
 577                         '  api.php?action=query&prop=revisions&titles=Main%20Page&rvlimit=5&rvprop=timestamp|user|comment&rvdir=newer',
 578                         'Get first 5 revisions of the "Main Page" made after 2006-05-01:',
 579                         '  api.php?action=query&prop=revisions&titles=Main%20Page&rvlimit=5&rvprop=timestamp|user|comment&rvdir=newer&rvstart=20060501000000',
 580                         'Get first 5 revisions of the "Main Page" that were not made made by anonymous user "127.0.0.1"',
 581                         '  api.php?action=query&prop=revisions&titles=Main%20Page&rvlimit=5&rvprop=timestamp|user|comment&rvexcludeuser=127.0.0.1',
 582                         'Get first 5 revisions of the "Main Page" that were made by the user "MediaWiki default"',
 583                         '  api.php?action=query&prop=revisions&titles=Main%20Page&rvlimit=5&rvprop=timestamp|user|comment&rvuser=MediaWiki%20default',
 584                 );
 585         }
 586
 587         public function getVersion() {
 588                 return __CLASS__ . ': $Id$';
 589         }
 590 }