includes/api/ApiQuery.php

   1 <?php
   2
   3 /**
   4  * Created on Sep 7, 2006
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright © 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  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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( 'ApiBase.php' );
  29 }
  30
  31 /**
  32  * This is the main query class. It behaves similar to ApiMain: based on the
  33  * parameters given, it will create a list of titles to work on (an ApiPageSet
  34  * object), instantiate and execute various property/list/meta modules, and
  35  * assemble all resulting data into a single ApiResult object.
  36  *
  37  * In generator mode, a generator will be executed first to populate a second
  38  * ApiPageSet object, and that object will be used for all subsequent modules.
  39  *
  40  * @ingroup API
  41  */
  42 class ApiQuery extends ApiBase {
  43
  44         private $mPropModuleNames, $mListModuleNames, $mMetaModuleNames;
  45         private $mPageSet;
  46         private $params, $redirect;
  47
  48         private $mQueryPropModules = array(
  49                 'info' => 'ApiQueryInfo',
  50                 'revisions' => 'ApiQueryRevisions',
  51                 'links' => 'ApiQueryLinks',
  52                 'iwlinks' => 'ApiQueryIWLinks',
  53                 'langlinks' => 'ApiQueryLangLinks',
  54                 'images' => 'ApiQueryImages',
  55                 'imageinfo' => 'ApiQueryImageInfo',
  56                 'templates' => 'ApiQueryLinks',
  57                 'categories' => 'ApiQueryCategories',
  58                 'extlinks' => 'ApiQueryExternalLinks',
  59                 'categoryinfo' => 'ApiQueryCategoryInfo',
  60                 'duplicatefiles' => 'ApiQueryDuplicateFiles',
  61         );
  62
  63         private $mQueryListModules = array(
  64                 'allimages' => 'ApiQueryAllimages',
  65                 'allpages' => 'ApiQueryAllpages',
  66                 'alllinks' => 'ApiQueryAllLinks',
  67                 'allcategories' => 'ApiQueryAllCategories',
  68                 'allusers' => 'ApiQueryAllUsers',
  69                 'backlinks' => 'ApiQueryBacklinks',
  70                 'blocks' => 'ApiQueryBlocks',
  71                 'categorymembers' => 'ApiQueryCategoryMembers',
  72                 'deletedrevs' => 'ApiQueryDeletedrevs',
  73                 'embeddedin' => 'ApiQueryBacklinks',
  74                 'filearchive' => 'ApiQueryFilearchive',
  75                 'imageusage' => 'ApiQueryBacklinks',
  76                 'iwbacklinks' => 'ApiQueryIWBacklinks',
  77                 'logevents' => 'ApiQueryLogEvents',
  78                 'recentchanges' => 'ApiQueryRecentChanges',
  79                 'search' => 'ApiQuerySearch',
  80                 'tags' => 'ApiQueryTags',
  81                 'usercontribs' => 'ApiQueryContributions',
  82                 'watchlist' => 'ApiQueryWatchlist',
  83                 'watchlistraw' => 'ApiQueryWatchlistRaw',
  84                 'exturlusage' => 'ApiQueryExtLinksUsage',
  85                 'users' => 'ApiQueryUsers',
  86                 'random' => 'ApiQueryRandom',
  87                 'protectedtitles' => 'ApiQueryProtectedTitles',
  88         );
  89
  90         private $mQueryMetaModules = array(
  91                 'siteinfo' => 'ApiQuerySiteinfo',
  92                 'userinfo' => 'ApiQueryUserInfo',
  93                 'allmessages' => 'ApiQueryAllmessages',
  94         );
  95
  96         private $mSlaveDB = null;
  97         private $mNamedDB = array();
  98
  99         public function __construct( $main, $action ) {
 100                 parent::__construct( $main, $action );
 101
 102                 // Allow custom modules to be added in LocalSettings.php
 103                 global $wgAPIPropModules, $wgAPIListModules, $wgAPIMetaModules;
 104                 self::appendUserModules( $this->mQueryPropModules, $wgAPIPropModules );
 105                 self::appendUserModules( $this->mQueryListModules, $wgAPIListModules );
 106                 self::appendUserModules( $this->mQueryMetaModules, $wgAPIMetaModules );
 107
 108                 $this->mPropModuleNames = array_keys( $this->mQueryPropModules );
 109                 $this->mListModuleNames = array_keys( $this->mQueryListModules );
 110                 $this->mMetaModuleNames = array_keys( $this->mQueryMetaModules );
 111
 112                 // Allow the entire list of modules at first,
 113                 // but during module instantiation check if it can be used as a generator.
 114                 $this->mAllowedGenerators = array_merge( $this->mListModuleNames, $this->mPropModuleNames );
 115         }
 116
 117         /**
 118          * Helper function to append any add-in modules to the list
 119          * @param $modules array Module array
 120          * @param $newModules array Module array to add to $modules
 121          */
 122         private static function appendUserModules( &$modules, $newModules ) {
 123                 if ( is_array( $newModules ) ) {
 124                         foreach ( $newModules as $moduleName => $moduleClass ) {
 125                                 $modules[$moduleName] = $moduleClass;
 126                         }
 127                 }
 128         }
 129
 130         /**
 131          * Gets a default slave database connection object
 132          * @return Database
 133          */
 134         public function getDB() {
 135                 if ( !isset( $this->mSlaveDB ) ) {
 136                         $this->profileDBIn();
 137                         $this->mSlaveDB = wfGetDB( DB_SLAVE, 'api' );
 138                         $this->profileDBOut();
 139                 }
 140                 return $this->mSlaveDB;
 141         }
 142
 143         /**
 144          * Get the query database connection with the given name.
 145          * If no such connection has been requested before, it will be created.
 146          * Subsequent calls with the same $name will return the same connection
 147          * as the first, regardless of the values of $db and $groups
 148          * @param $name string Name to assign to the database connection
 149          * @param $db int One of the DB_* constants
 150          * @param $groups array Query groups
 151          * @return Database
 152          */
 153         public function getNamedDB( $name, $db, $groups ) {
 154                 if ( !array_key_exists( $name, $this->mNamedDB ) ) {
 155                         $this->profileDBIn();
 156                         $this->mNamedDB[$name] = wfGetDB( $db, $groups );
 157                         $this->profileDBOut();
 158                 }
 159                 return $this->mNamedDB[$name];
 160         }
 161
 162         /**
 163          * Gets the set of pages the user has requested (or generated)
 164          * @return ApiPageSet
 165          */
 166         public function getPageSet() {
 167                 return $this->mPageSet;
 168         }
 169
 170         /**
 171          * Get the array mapping module names to class names
 172          * @return array(modulename => classname)
 173          */
 174         function getModules() {
 175                 return array_merge( $this->mQueryPropModules, $this->mQueryListModules, $this->mQueryMetaModules );
 176         }
 177
 178         /**
 179          * Get whether the specified module is a prop, list or a meta query module
 180          * @param $moduleName string Name of the module to find type for
 181          * @return mixed string or null
 182          */
 183         function getModuleType( $moduleName ) {
 184                 if ( array_key_exists ( $moduleName, $this->mQueryPropModules ) ) {
 185                         return 'prop';
 186                 }
 187
 188                 if ( array_key_exists ( $moduleName, $this->mQueryListModules ) ) {
 189                         return 'list';
 190                 }
 191
 192                 if ( array_key_exists ( $moduleName, $this->mQueryMetaModules ) ) {
 193                         return 'meta';
 194                 }
 195
 196                 return null;
 197         }
 198
 199         public function getCustomPrinter() {
 200                 // If &exportnowrap is set, use the raw formatter
 201                 if ( $this->getParameter( 'export' ) &&
 202                                 $this->getParameter( 'exportnowrap' ) )
 203                 {
 204                         return new ApiFormatRaw( $this->getMain(),
 205                                 $this->getMain()->createPrinterByName( 'xml' ) );
 206                 } else {
 207                         return null;
 208                 }
 209         }
 210
 211         /**
 212          * Query execution happens in the following steps:
 213          * #1 Create a PageSet object with any pages requested by the user
 214          * #2 If using a generator, execute it to get a new ApiPageSet object
 215          * #3 Instantiate all requested modules.
 216          *    This way the PageSet object will know what shared data is required,
 217          *    and minimize DB calls.
 218          * #4 Output all normalization and redirect resolution information
 219          * #5 Execute all requested modules
 220          */
 221         public function execute() {
 222                 $this->params = $this->extractRequestParams();
 223                 $this->redirects = $this->params['redirects'];
 224                 $this->convertTitles = $this->params['converttitles'];
 225
 226                 // Create PageSet
 227                 $this->mPageSet = new ApiPageSet( $this, $this->redirects, $this->convertTitles );
 228
 229                 // Instantiate requested modules
 230                 $modules = array();
 231                 $this->instantiateModules( $modules, 'prop', $this->mQueryPropModules );
 232                 $this->instantiateModules( $modules, 'list', $this->mQueryListModules );
 233                 $this->instantiateModules( $modules, 'meta', $this->mQueryMetaModules );
 234
 235                 // If given, execute generator to substitute user supplied data with generated data.
 236                 if ( isset( $this->params['generator'] ) ) {
 237                         $this->executeGeneratorModule( $this->params['generator'], $modules );
 238                 } else {
 239                         // Append custom fields and populate page/revision information
 240                         $this->addCustomFldsToPageSet( $modules, $this->mPageSet );
 241                         $this->mPageSet->execute();
 242                 }
 243
 244                 // Record page information (title, namespace, if exists, etc)
 245                 $this->outputGeneralPageInfo();
 246
 247                 // Execute all requested modules.
 248                 foreach ( $modules as $module ) {
 249                         $module->profileIn();
 250                         $module->execute();
 251                         wfRunHooks( 'APIQueryAfterExecute', array( &$module ) );
 252                         $module->profileOut();
 253                 }
 254         }
 255
 256         /**
 257          * Query modules may optimize data requests through the $this->getPageSet() object
 258          * by adding extra fields from the page table.
 259          * This function will gather all the extra request fields from the modules.
 260          * @param $modules array of module objects
 261          * @param $pageSet ApiPageSet
 262          */
 263         private function addCustomFldsToPageSet( $modules, $pageSet ) {
 264                 // Query all requested modules.
 265                 foreach ( $modules as $module ) {
 266                         $module->requestExtraData( $pageSet );
 267                 }
 268         }
 269
 270         /**
 271          * Create instances of all modules requested by the client
 272          * @param $modules array to append instatiated modules to
 273          * @param $param string Parameter name to read modules from
 274          * @param $moduleList array(modulename => classname)
 275          */
 276         private function instantiateModules( &$modules, $param, $moduleList ) {
 277                 $list = @$this->params[$param];
 278                 if ( !is_null ( $list ) ) {
 279                         foreach ( $list as $moduleName ) {
 280                                 $modules[] = new $moduleList[$moduleName] ( $this, $moduleName );
 281                         }
 282                 }
 283         }
 284
 285         /**
 286          * Appends an element for each page in the current pageSet with the
 287          * most general information (id, title), plus any title normalizations
 288          * and missing or invalid title/pageids/revids.
 289          */
 290         private function outputGeneralPageInfo() {
 291                 $pageSet = $this->getPageSet();
 292                 $result = $this->getResult();
 293
 294                 // We don't check for a full result set here because we can't be adding
 295                 // more than 380K. The maximum revision size is in the megabyte range,
 296                 // and the maximum result size must be even higher than that.
 297
 298                 // Title normalizations
 299                 $normValues = array();
 300                 foreach ( $pageSet->getNormalizedTitles() as $rawTitleStr => $titleStr ) {
 301                         $normValues[] = array(
 302                                 'from' => $rawTitleStr,
 303                                 'to' => $titleStr
 304                         );
 305                 }
 306
 307                 if ( count( $normValues ) ) {
 308                         $result->setIndexedTagName( $normValues, 'n' );
 309                         $result->addValue( 'query', 'normalized', $normValues );
 310                 }
 311
 312                 // Title conversions
 313                 $convValues = array();
 314                 foreach ( $pageSet->getConvertedTitles() as $rawTitleStr => $titleStr ) {
 315                         $convValues[] = array(
 316                                 'from' => $rawTitleStr,
 317                                 'to' => $titleStr
 318                         );
 319                 }
 320
 321                 if ( count( $convValues ) ) {
 322                         $result->setIndexedTagName( $convValues, 'c' );
 323                         $result->addValue( 'query', 'converted', $convValues );
 324                 }
 325
 326                 // Interwiki titles
 327                 $intrwValues = array();
 328                 foreach ( $pageSet->getInterwikiTitles() as $rawTitleStr => $interwikiStr ) {
 329                         $intrwValues[] = array(
 330                                 'title' => $rawTitleStr,
 331                                 'iw' => $interwikiStr
 332                         );
 333                 }
 334
 335                 if ( count( $intrwValues ) ) {
 336                         $result->setIndexedTagName( $intrwValues, 'i' );
 337                         $result->addValue( 'query', 'interwiki', $intrwValues );
 338                 }
 339
 340                 // Show redirect information
 341                 $redirValues = array();
 342                 foreach ( $pageSet->getRedirectTitles() as $titleStrFrom => $titleStrTo ) {
 343                         $redirValues[] = array(
 344                                 'from' => strval( $titleStrFrom ),
 345                                 'to' => $titleStrTo
 346                         );
 347                 }
 348
 349                 if ( count( $redirValues ) ) {
 350                         $result->setIndexedTagName( $redirValues, 'r' );
 351                         $result->addValue( 'query', 'redirects', $redirValues );
 352                 }
 353
 354                 //
 355                 // Missing revision elements
 356                 //
 357                 $missingRevIDs = $pageSet->getMissingRevisionIDs();
 358                 if ( count( $missingRevIDs ) ) {
 359                         $revids = array();
 360                         foreach ( $missingRevIDs as $revid ) {
 361                                 $revids[$revid] = array(
 362                                         'revid' => $revid
 363                                 );
 364                         }
 365                         $result->setIndexedTagName( $revids, 'rev' );
 366                         $result->addValue( 'query', 'badrevids', $revids );
 367                 }
 368
 369                 //
 370                 // Page elements
 371                 //
 372                 $pages = array();
 373
 374                 // Report any missing titles
 375                 foreach ( $pageSet->getMissingTitles() as $fakeId => $title ) {
 376                         $vals = array();
 377                         ApiQueryBase::addTitleInfo( $vals, $title );
 378                         $vals['missing'] = '';
 379                         $pages[$fakeId] = $vals;
 380                 }
 381                 // Report any invalid titles
 382                 foreach ( $pageSet->getInvalidTitles() as $fakeId => $title ) {
 383                         $pages[$fakeId] = array( 'title' => $title, 'invalid' => '' );
 384                 }
 385                 // Report any missing page ids
 386                 foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
 387                         $pages[$pageid] = array(
 388                                 'pageid' => $pageid,
 389                                 'missing' => ''
 390                         );
 391                 }
 392                 // Report special pages
 393                 foreach ( $pageSet->getSpecialTitles() as $fakeId => $title ) {
 394                         $vals = array();
 395                         ApiQueryBase::addTitleInfo( $vals, $title );
 396                         $vals['special'] = '';
 397                         if ( $title->getNamespace() == NS_SPECIAL &&
 398                                         !SpecialPage::exists( $title->getText() ) ) {
 399                                 $vals['missing'] = '';
 400                         } elseif ( $title->getNamespace() == NS_MEDIA &&
 401                                         !wfFindFile( $title ) ) {
 402                                 $vals['missing'] = '';
 403                         }
 404                         $pages[$fakeId] = $vals;
 405                 }
 406
 407                 // Output general page information for found titles
 408                 foreach ( $pageSet->getGoodTitles() as $pageid => $title ) {
 409                         $vals = array();
 410                         $vals['pageid'] = $pageid;
 411                         ApiQueryBase::addTitleInfo( $vals, $title );
 412                         $pages[$pageid] = $vals;
 413                 }
 414
 415                 if ( count( $pages ) ) {
 416                         if ( $this->params['indexpageids'] ) {
 417                                 $pageIDs = array_keys( $pages );
 418                                 // json treats all map keys as strings - converting to match
 419                                 $pageIDs = array_map( 'strval', $pageIDs );
 420                                 $result->setIndexedTagName( $pageIDs, 'id' );
 421                                 $result->addValue( 'query', 'pageids', $pageIDs );
 422                         }
 423
 424                         $result->setIndexedTagName( $pages, 'page' );
 425                         $result->addValue( 'query', 'pages', $pages );
 426                 }
 427                 if ( $this->params['export'] ) {
 428                         $exporter = new WikiExporter( $this->getDB() );
 429                         // WikiExporter writes to stdout, so catch its
 430                         // output with an ob
 431                         ob_start();
 432                         $exporter->openStream();
 433                         foreach ( @$pageSet->getGoodTitles() as $title ) {
 434                                 if ( $title->userCanRead() ) {
 435                                         $exporter->pageByTitle( $title );
 436                                 }
 437                         }
 438                         $exporter->closeStream();
 439                         $exportxml = ob_get_contents();
 440                         ob_end_clean();
 441
 442                         // Don't check the size of exported stuff
 443                         // It's not continuable, so it would cause more
 444                         // problems than it'd solve
 445                         $result->disableSizeCheck();
 446                         if ( $this->params['exportnowrap'] ) {
 447                                 $result->reset();
 448                                 // Raw formatter will handle this
 449                                 $result->addValue( null, 'text', $exportxml );
 450                                 $result->addValue( null, 'mime', 'text/xml' );
 451                         } else {
 452                                 $r = array();
 453                                 ApiResult::setContent( $r, $exportxml );
 454                                 $result->addValue( 'query', 'export', $r );
 455                         }
 456                         $result->enableSizeCheck();
 457                 }
 458         }
 459
 460         /**
 461          * For generator mode, execute generator, and use its output as new
 462          * ApiPageSet
 463          * @param $generatorName string Module name
 464          * @param $modules array of module objects
 465          */
 466         protected function executeGeneratorModule( $generatorName, $modules ) {
 467                 // Find class that implements requested generator
 468                 if ( isset( $this->mQueryListModules[$generatorName] ) ) {
 469                         $className = $this->mQueryListModules[$generatorName];
 470                 } elseif ( isset( $this->mQueryPropModules[$generatorName] ) ) {
 471                         $className = $this->mQueryPropModules[$generatorName];
 472                 } else {
 473                         ApiBase::dieDebug( __METHOD__, "Unknown generator=$generatorName" );
 474                 }
 475
 476                 // Generator results
 477                 $resultPageSet = new ApiPageSet( $this, $this->redirects, $this->convertTitles );
 478
 479                 // Create and execute the generator
 480                 $generator = new $className ( $this, $generatorName );
 481                 if ( !$generator instanceof ApiQueryGeneratorBase ) {
 482                         $this->dieUsage( "Module $generatorName cannot be used as a generator", 'badgenerator' );
 483                 }
 484
 485                 $generator->setGeneratorMode();
 486
 487                 // Add any additional fields modules may need
 488                 $generator->requestExtraData( $this->mPageSet );
 489                 $this->addCustomFldsToPageSet( $modules, $resultPageSet );
 490
 491                 // Populate page information with the original user input
 492                 $this->mPageSet->execute();
 493
 494                 // populate resultPageSet with the generator output
 495                 $generator->profileIn();
 496                 $generator->executeGenerator( $resultPageSet );
 497                 wfRunHooks( 'APIQueryGeneratorAfterExecute', array( &$generator, &$resultPageSet ) );
 498                 $resultPageSet->finishPageSetGeneration();
 499                 $generator->profileOut();
 500
 501                 // Swap the resulting pageset back in
 502                 $this->mPageSet = $resultPageSet;
 503         }
 504
 505         public function getAllowedParams() {
 506                 return array(
 507                         'prop' => array(
 508                                 ApiBase::PARAM_ISMULTI => true,
 509                                 ApiBase::PARAM_TYPE => $this->mPropModuleNames
 510                         ),
 511                         'list' => array(
 512                                 ApiBase::PARAM_ISMULTI => true,
 513                                 ApiBase::PARAM_TYPE => $this->mListModuleNames
 514                         ),
 515                         'meta' => array(
 516                                 ApiBase::PARAM_ISMULTI => true,
 517                                 ApiBase::PARAM_TYPE => $this->mMetaModuleNames
 518                         ),
 519                         'generator' => array(
 520                                 ApiBase::PARAM_TYPE => $this->mAllowedGenerators
 521                         ),
 522                         'redirects' => false,
 523                         'converttitles' => false,
 524                         'indexpageids' => false,
 525                         'export' => false,
 526                         'exportnowrap' => false,
 527                 );
 528         }
 529
 530         /**
 531          * Override the parent to generate help messages for all available query modules.
 532          * @return string
 533          */
 534         public function makeHelpMsg() {
 535                 $msg = '';
 536
 537                 // Make sure the internal object is empty
 538                 // (just in case a sub-module decides to optimize during instantiation)
 539                 $this->mPageSet = null;
 540                 $this->mAllowedGenerators = array(); // Will be repopulated
 541
 542                 $astriks = str_repeat( '--- ', 8 );
 543                 $astriks2 = str_repeat( '*** ', 10 );
 544                 $msg .= "\n$astriks Query: Prop  $astriks\n\n";
 545                 $msg .= $this->makeHelpMsgHelper( $this->mQueryPropModules, 'prop' );
 546                 $msg .= "\n$astriks Query: List  $astriks\n\n";
 547                 $msg .= $this->makeHelpMsgHelper( $this->mQueryListModules, 'list' );
 548                 $msg .= "\n$astriks Query: Meta  $astriks\n\n";
 549                 $msg .= $this->makeHelpMsgHelper( $this->mQueryMetaModules, 'meta' );
 550                 $msg .= "\n\n$astriks2 Modules: continuation  $astriks2\n\n";
 551
 552                 // Perform the base call last because the $this->mAllowedGenerators
 553                 // will be updated inside makeHelpMsgHelper()
 554                 // Use parent to make default message for the query module
 555                 $msg = parent::makeHelpMsg() . $msg;
 556
 557                 return $msg;
 558         }
 559
 560         /**
 561          * For all modules in $moduleList, generate help messages and join them together
 562          * @param $moduleList array(modulename => classname)
 563          * @param $paramName string Parameter name
 564          * @return string
 565          */
 566         private function makeHelpMsgHelper( $moduleList, $paramName ) {
 567                 $moduleDescriptions = array();
 568
 569                 foreach ( $moduleList as $moduleName => $moduleClass ) {
 570                         $module = new $moduleClass ( $this, $moduleName, null );
 571
 572                         $msg = ApiMain::makeHelpMsgHeader( $module, $paramName );
 573                         $msg2 = $module->makeHelpMsg();
 574                         if ( $msg2 !== false ) {
 575                                 $msg .= $msg2;
 576                         }
 577                         if ( $module instanceof ApiQueryGeneratorBase ) {
 578                                 $this->mAllowedGenerators[] = $moduleName;
 579                                 $msg .= "Generator:\n  This module may be used as a generator\n";
 580                         }
 581                         $moduleDescriptions[] = $msg;
 582                 }
 583
 584                 return implode( "\n", $moduleDescriptions );
 585         }
 586
 587         /**
 588          * Override to add extra parameters from PageSet
 589          * @return string
 590          */
 591         public function makeHelpMsgParameters() {
 592                 $psModule = new ApiPageSet( $this );
 593                 return $psModule->makeHelpMsgParameters() . parent::makeHelpMsgParameters();
 594         }
 595
 596         public function shouldCheckMaxlag() {
 597                 return true;
 598         }
 599
 600         public function getParamDescription() {
 601                 return array(
 602                         'prop' => 'Which properties to get for the titles/revisions/pageids. Module help is available below',
 603                         'list' => 'Which lists to get. Module help is available below',
 604                         'meta' => 'Which metadata to get about the site. Module help is available below',
 605                         'generator' => array( 'Use the output of a list as the input for other prop/list/meta items',
 606                                         'NOTE: generator parameter names must be prefixed with a \'g\', see examples' ),
 607                         'redirects' => 'Automatically resolve redirects',
 608                         'converttitles' => "Convert titles to other variants if necessary. Only works if the wiki's content language supports variant conversion.",
 609                         'indexpageids' => 'Include an additional pageids section listing all returned page IDs',
 610                         'export' => 'Export the current revisions of all given or generated pages',
 611                         'exportnowrap' => 'Return the export XML without wrapping it in an XML result (same format as Special:Export). Can only be used with export',
 612                 );
 613         }
 614
 615         public function getDescription() {
 616                 return array(
 617                         'Query API module allows applications to get needed pieces of data from the MediaWiki databases,',
 618                         'and is loosely based on the old query.php interface.',
 619                         'All data modifications will first have to use query to acquire a token to prevent abuse from malicious sites'
 620                 );
 621         }
 622
 623         public function getPossibleErrors() {
 624                 return array_merge( parent::getPossibleErrors(), array(
 625                         array( 'code' => 'badgenerator', 'info' => 'Module $generatorName cannot be used as a generator' ),
 626                 ) );
 627         }
 628
 629         protected function getExamples() {
 630                 return array(
 631                         'api.php?action=query&prop=revisions&meta=siteinfo&titles=Main%20Page&rvprop=user|comment',
 632                         'api.php?action=query&generator=allpages&gapprefix=API/&prop=revisions',
 633                 );
 634         }
 635
 636         public function getVersion() {
 637                 $psModule = new ApiPageSet( $this );
 638                 $vers = array();
 639                 $vers[] = __CLASS__ . ': $Id$';
 640                 $vers[] = $psModule->getVersion();
 641                 return $vers;
 642         }
 643 }