includes/api/ApiQuery.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on Sep 7, 2006
   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  * This is the main query class. It behaves similar to ApiMain: based on the
  29  * parameters given, it will create a list of titles to work on (an ApiPageSet
  30  * object), instantiate and execute various property/list/meta modules, and
  31  * assemble all resulting data into a single ApiResult object.
  32  *
  33  * In generator mode, a generator will be executed first to populate a second
  34  * ApiPageSet object, and that object will be used for all subsequent modules.
  35  *
  36  * @ingroup API
  37  */
  38 class ApiQuery extends ApiBase {
  39
  40         /**
  41          * List of Api Query prop modules
  42          * @var array
  43          */
  44         private static $QueryPropModules = array(
  45                 'categories' => 'ApiQueryCategories',
  46                 'categoryinfo' => 'ApiQueryCategoryInfo',
  47                 'duplicatefiles' => 'ApiQueryDuplicateFiles',
  48                 'extlinks' => 'ApiQueryExternalLinks',
  49                 'images' => 'ApiQueryImages',
  50                 'imageinfo' => 'ApiQueryImageInfo',
  51                 'info' => 'ApiQueryInfo',
  52                 'links' => 'ApiQueryLinks',
  53                 'iwlinks' => 'ApiQueryIWLinks',
  54                 'langlinks' => 'ApiQueryLangLinks',
  55                 'pageprops' => 'ApiQueryPageProps',
  56                 'revisions' => 'ApiQueryRevisions',
  57                 'stashimageinfo' => 'ApiQueryStashImageInfo',
  58                 'templates' => 'ApiQueryLinks',
  59         );
  60
  61         /**
  62          * List of Api Query list modules
  63          * @var array
  64          */
  65         private static $QueryListModules = array(
  66                 'allcategories' => 'ApiQueryAllCategories',
  67                 'allimages' => 'ApiQueryAllImages',
  68                 'alllinks' => 'ApiQueryAllLinks',
  69                 'allpages' => 'ApiQueryAllPages',
  70                 'alltransclusions' => 'ApiQueryAllLinks',
  71                 'allusers' => 'ApiQueryAllUsers',
  72                 'backlinks' => 'ApiQueryBacklinks',
  73                 'blocks' => 'ApiQueryBlocks',
  74                 'categorymembers' => 'ApiQueryCategoryMembers',
  75                 'deletedrevs' => 'ApiQueryDeletedrevs',
  76                 'embeddedin' => 'ApiQueryBacklinks',
  77                 'exturlusage' => 'ApiQueryExtLinksUsage',
  78                 'filearchive' => 'ApiQueryFilearchive',
  79                 'imageusage' => 'ApiQueryBacklinks',
  80                 'iwbacklinks' => 'ApiQueryIWBacklinks',
  81                 'langbacklinks' => 'ApiQueryLangBacklinks',
  82                 'logevents' => 'ApiQueryLogEvents',
  83                 'protectedtitles' => 'ApiQueryProtectedTitles',
  84                 'querypage' => 'ApiQueryQueryPage',
  85                 'random' => 'ApiQueryRandom',
  86                 'recentchanges' => 'ApiQueryRecentChanges',
  87                 'search' => 'ApiQuerySearch',
  88                 'tags' => 'ApiQueryTags',
  89                 'usercontribs' => 'ApiQueryContributions',
  90                 'users' => 'ApiQueryUsers',
  91                 'watchlist' => 'ApiQueryWatchlist',
  92                 'watchlistraw' => 'ApiQueryWatchlistRaw',
  93         );
  94
  95         /**
  96          * List of Api Query meta modules
  97          * @var array
  98          */
  99         private static $QueryMetaModules = array(
 100                 'allmessages' => 'ApiQueryAllMessages',
 101                 'siteinfo' => 'ApiQuerySiteinfo',
 102                 'userinfo' => 'ApiQueryUserInfo',
 103         );
 104
 105         /**
 106          * List of Api Query generator modules
 107          * Defined in code, rather than being derived at runtime,
 108          * due to performance reasons
 109          * @var array
 110          */
 111         private $mQueryGenerators = array(
 112                 'allcategories' => 'ApiQueryAllCategories',
 113                 'allimages' => 'ApiQueryAllImages',
 114                 'alllinks' => 'ApiQueryAllLinks',
 115                 'allpages' => 'ApiQueryAllPages',
 116                 'alltransclusions' => 'ApiQueryAllLinks',
 117                 'backlinks' => 'ApiQueryBacklinks',
 118                 'categories' => 'ApiQueryCategories',
 119                 'categorymembers' => 'ApiQueryCategoryMembers',
 120                 'duplicatefiles' => 'ApiQueryDuplicateFiles',
 121                 'embeddedin' => 'ApiQueryBacklinks',
 122                 'exturlusage' => 'ApiQueryExtLinksUsage',
 123                 'images' => 'ApiQueryImages',
 124                 'imageusage' => 'ApiQueryBacklinks',
 125                 'iwbacklinks' => 'ApiQueryIWBacklinks',
 126                 'langbacklinks' => 'ApiQueryLangBacklinks',
 127                 'links' => 'ApiQueryLinks',
 128                 'protectedtitles' => 'ApiQueryProtectedTitles',
 129                 'querypage' => 'ApiQueryQueryPage',
 130                 'random' => 'ApiQueryRandom',
 131                 'recentchanges' => 'ApiQueryRecentChanges',
 132                 'search' => 'ApiQuerySearch',
 133                 'templates' => 'ApiQueryLinks',
 134                 'watchlist' => 'ApiQueryWatchlist',
 135                 'watchlistraw' => 'ApiQueryWatchlistRaw',
 136         );
 137
 138         /**
 139          * @var ApiPageSet
 140          */
 141         private $mPageSet;
 142
 143         private $params, $redirects, $convertTitles, $iwUrl;
 144         private $mSlaveDB = null;
 145         private $mNamedDB = array();
 146         private $mModuleMgr;
 147
 148         protected $mAllowedGenerators;
 149
 150         /**
 151          * @param $main ApiMain
 152          * @param $action string
 153          */
 154         public function __construct( $main, $action ) {
 155                 parent::__construct( $main, $action );
 156
 157                 $this->mModuleMgr = new ApiModuleManager( $this );
 158
 159                 // Allow custom modules to be added in LocalSettings.php
 160                 global $wgAPIPropModules, $wgAPIListModules, $wgAPIMetaModules;
 161                 $this->mModuleMgr->addModules( self::$QueryPropModules, 'prop' );
 162                 $this->mModuleMgr->addModules( $wgAPIPropModules, 'prop' );
 163                 $this->mModuleMgr->addModules( self::$QueryListModules, 'list' );
 164                 $this->mModuleMgr->addModules( $wgAPIListModules, 'list' );
 165                 $this->mModuleMgr->addModules( self::$QueryMetaModules, 'meta' );
 166                 $this->mModuleMgr->addModules( $wgAPIMetaModules, 'meta' );
 167
 168                 global $wgAPIGeneratorModules;
 169                 if ( is_array( $wgAPIGeneratorModules ) ) {
 170                         foreach ( $wgAPIGeneratorModules as $moduleName => $moduleClass ) {
 171                                 $this->mQueryGenerators[$moduleName] = $moduleClass;
 172                         }
 173                 }
 174                 $this->mAllowedGenerators = array_keys( $this->mQueryGenerators );
 175         }
 176
 177         /**
 178          * Overrides to return this instance's module manager.
 179          * @return ApiModuleManager
 180          */
 181         public function getModuleManager() {
 182                 return $this->mModuleMgr;
 183         }
 184
 185         /**
 186          * Gets a default slave database connection object
 187          * @return DatabaseBase
 188          */
 189         public function getDB() {
 190                 if ( !isset( $this->mSlaveDB ) ) {
 191                         $this->profileDBIn();
 192                         $this->mSlaveDB = wfGetDB( DB_SLAVE, 'api' );
 193                         $this->profileDBOut();
 194                 }
 195                 return $this->mSlaveDB;
 196         }
 197
 198         /**
 199          * Get the query database connection with the given name.
 200          * If no such connection has been requested before, it will be created.
 201          * Subsequent calls with the same $name will return the same connection
 202          * as the first, regardless of the values of $db and $groups
 203          * @param $name string Name to assign to the database connection
 204          * @param $db int One of the DB_* constants
 205          * @param $groups array Query groups
 206          * @return DatabaseBase
 207          */
 208         public function getNamedDB( $name, $db, $groups ) {
 209                 if ( !array_key_exists( $name, $this->mNamedDB ) ) {
 210                         $this->profileDBIn();
 211                         $this->mNamedDB[$name] = wfGetDB( $db, $groups );
 212                         $this->profileDBOut();
 213                 }
 214                 return $this->mNamedDB[$name];
 215         }
 216
 217         /**
 218          * Gets the set of pages the user has requested (or generated)
 219          * @return ApiPageSet
 220          */
 221         public function getPageSet() {
 222                 return $this->mPageSet;
 223         }
 224
 225         /**
 226          * Get the array mapping module names to class names
 227          * @deprecated since 1.21, use getModuleManager()'s methods instead
 228          * @return array array(modulename => classname)
 229          */
 230         public function getModules() {
 231                 return $this->getModuleManager()->getNamesWithClasses();
 232         }
 233
 234         /**
 235          * Get the generators array mapping module names to class names
 236          * @return array array(modulename => classname)
 237          */
 238         public function getGenerators() {
 239                 return $this->mQueryGenerators;
 240         }
 241
 242         /**
 243          * Get whether the specified module is a prop, list or a meta query module
 244          * @deprecated since 1.21, use getModuleManager()->getModuleGroup()
 245          * @param $moduleName string Name of the module to find type for
 246          * @return mixed string or null
 247          */
 248         function getModuleType( $moduleName ) {
 249                 return $this->getModuleManager()->getModuleGroup( $moduleName );
 250         }
 251
 252         /**
 253          * @return ApiFormatRaw|null
 254          */
 255         public function getCustomPrinter() {
 256                 // If &exportnowrap is set, use the raw formatter
 257                 if ( $this->getParameter( 'export' ) &&
 258                                 $this->getParameter( 'exportnowrap' ) )
 259                 {
 260                         return new ApiFormatRaw( $this->getMain(),
 261                                 $this->getMain()->createPrinterByName( 'xml' ) );
 262                 } else {
 263                         return null;
 264                 }
 265         }
 266
 267         /**
 268          * Query execution happens in the following steps:
 269          * #1 Create a PageSet object with any pages requested by the user
 270          * #2 If using a generator, execute it to get a new ApiPageSet object
 271          * #3 Instantiate all requested modules.
 272          *    This way the PageSet object will know what shared data is required,
 273          *    and minimize DB calls.
 274          * #4 Output all normalization and redirect resolution information
 275          * #5 Execute all requested modules
 276          */
 277         public function execute() {
 278                 $this->params = $this->extractRequestParams();
 279                 $this->redirects = $this->params['redirects'];
 280                 $this->convertTitles = $this->params['converttitles'];
 281                 $this->iwUrl = $this->params['iwurl'];
 282
 283                 // Create PageSet
 284                 $this->mPageSet = new ApiPageSet( $this, $this->redirects, $this->convertTitles );
 285
 286                 // Instantiate requested modules
 287                 $modules = array();
 288                 $this->instantiateModules( $modules, 'prop' );
 289                 $this->instantiateModules( $modules, 'list' );
 290                 $this->instantiateModules( $modules, 'meta' );
 291
 292                 $cacheMode = 'public';
 293
 294                 // If given, execute generator to substitute user supplied data with generated data.
 295                 if ( isset( $this->params['generator'] ) ) {
 296                         $generator = $this->newGenerator( $this->params['generator'] );
 297                         $params = $generator->extractRequestParams();
 298                         $cacheMode = $this->mergeCacheMode( $cacheMode,
 299                                 $generator->getCacheMode( $params ) );
 300                         $this->executeGeneratorModule( $generator, $modules );
 301                 } else {
 302                         // Append custom fields and populate page/revision information
 303                         $this->addCustomFldsToPageSet( $modules, $this->mPageSet );
 304                         $this->mPageSet->execute();
 305                 }
 306
 307                 // Record page information (title, namespace, if exists, etc)
 308                 $this->outputGeneralPageInfo();
 309
 310                 // Execute all requested modules.
 311                 /**
 312                  * @var $module ApiQueryBase
 313                  */
 314                 foreach ( $modules as $module ) {
 315                         $params = $module->extractRequestParams();
 316                         $cacheMode = $this->mergeCacheMode(
 317                                 $cacheMode, $module->getCacheMode( $params ) );
 318                         $module->profileIn();
 319                         $module->execute();
 320                         wfRunHooks( 'APIQueryAfterExecute', array( &$module ) );
 321                         $module->profileOut();
 322                 }
 323
 324                 // Set the cache mode
 325                 $this->getMain()->setCacheMode( $cacheMode );
 326         }
 327
 328         /**
 329          * Update a cache mode string, applying the cache mode of a new module to it.
 330          * The cache mode may increase in the level of privacy, but public modules
 331          * added to private data do not decrease the level of privacy.
 332          *
 333          * @param $cacheMode string
 334          * @param $modCacheMode string
 335          * @return string
 336          */
 337         protected function mergeCacheMode( $cacheMode, $modCacheMode ) {
 338                 if ( $modCacheMode === 'anon-public-user-private' ) {
 339                         if ( $cacheMode !== 'private' ) {
 340                                 $cacheMode = 'anon-public-user-private';
 341                         }
 342                 } elseif ( $modCacheMode === 'public' ) {
 343                         // do nothing, if it's public already it will stay public
 344                 } else { // private
 345                         $cacheMode = 'private';
 346                 }
 347                 return $cacheMode;
 348         }
 349
 350         /**
 351          * Query modules may optimize data requests through the $this->getPageSet() object
 352          * by adding extra fields from the page table.
 353          * This function will gather all the extra request fields from the modules.
 354          * @param $modules array of module objects
 355          * @param $pageSet ApiPageSet
 356          */
 357         private function addCustomFldsToPageSet( $modules, $pageSet ) {
 358                 // Query all requested modules.
 359                 /**
 360                  * @var $module ApiQueryBase
 361                  */
 362                 foreach ( $modules as $module ) {
 363                         $module->requestExtraData( $pageSet );
 364                 }
 365         }
 366
 367         /**
 368          * Create instances of all modules requested by the client
 369          * @param $modules Array to append instantiated modules to
 370          * @param $param string Parameter name to read modules from
 371          */
 372         private function instantiateModules( &$modules, $param ) {
 373                 if ( isset( $this->params[$param] ) ) {
 374                         foreach ( $this->params[$param] as $moduleName ) {
 375                                 $modules[] = $this->mModuleMgr->getModule( $moduleName );
 376                         }
 377                 }
 378         }
 379
 380         /**
 381          * Appends an element for each page in the current pageSet with the
 382          * most general information (id, title), plus any title normalizations
 383          * and missing or invalid title/pageids/revids.
 384          */
 385         private function outputGeneralPageInfo() {
 386                 $pageSet = $this->getPageSet();
 387                 $result = $this->getResult();
 388
 389                 // We don't check for a full result set here because we can't be adding
 390                 // more than 380K. The maximum revision size is in the megabyte range,
 391                 // and the maximum result size must be even higher than that.
 392
 393                 // Title normalizations
 394                 $normValues = array();
 395                 foreach ( $pageSet->getNormalizedTitles() as $rawTitleStr => $titleStr ) {
 396                         $normValues[] = array(
 397                                 'from' => $rawTitleStr,
 398                                 'to' => $titleStr
 399                         );
 400                 }
 401
 402                 if ( count( $normValues ) ) {
 403                         $result->setIndexedTagName( $normValues, 'n' );
 404                         $result->addValue( 'query', 'normalized', $normValues );
 405                 }
 406
 407                 // Title conversions
 408                 $convValues = array();
 409                 foreach ( $pageSet->getConvertedTitles() as $rawTitleStr => $titleStr ) {
 410                         $convValues[] = array(
 411                                 'from' => $rawTitleStr,
 412                                 'to' => $titleStr
 413                         );
 414                 }
 415
 416                 if ( count( $convValues ) ) {
 417                         $result->setIndexedTagName( $convValues, 'c' );
 418                         $result->addValue( 'query', 'converted', $convValues );
 419                 }
 420
 421                 // Interwiki titles
 422                 $intrwValues = array();
 423                 foreach ( $pageSet->getInterwikiTitles() as $rawTitleStr => $interwikiStr ) {
 424                         $item = array(
 425                                 'title' => $rawTitleStr,
 426                                 'iw' => $interwikiStr,
 427                         );
 428                         if ( $this->iwUrl ) {
 429                                 $title = Title::newFromText( $rawTitleStr );
 430                                 $item['url'] = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
 431                         }
 432                         $intrwValues[] = $item;
 433                 }
 434
 435                 if ( count( $intrwValues ) ) {
 436                         $result->setIndexedTagName( $intrwValues, 'i' );
 437                         $result->addValue( 'query', 'interwiki', $intrwValues );
 438                 }
 439
 440                 // Show redirect information
 441                 $redirValues = array();
 442                 /**
 443                  * @var $titleTo Title
 444                  */
 445                 foreach ( $pageSet->getRedirectTitles() as $titleStrFrom => $titleTo ) {
 446                         $r = array(
 447                                 'from' => strval( $titleStrFrom ),
 448                                 'to' => $titleTo->getPrefixedText(),
 449                         );
 450                         if ( $titleTo->getFragment() !== '' ) {
 451                                 $r['tofragment'] = $titleTo->getFragment();
 452                         }
 453                         $redirValues[] = $r;
 454                 }
 455
 456                 if ( count( $redirValues ) ) {
 457                         $result->setIndexedTagName( $redirValues, 'r' );
 458                         $result->addValue( 'query', 'redirects', $redirValues );
 459                 }
 460
 461                 // Missing revision elements
 462                 $missingRevIDs = $pageSet->getMissingRevisionIDs();
 463                 if ( count( $missingRevIDs ) ) {
 464                         $revids = array();
 465                         foreach ( $missingRevIDs as $revid ) {
 466                                 $revids[$revid] = array(
 467                                         'revid' => $revid
 468                                 );
 469                         }
 470                         $result->setIndexedTagName( $revids, 'rev' );
 471                         $result->addValue( 'query', 'badrevids', $revids );
 472                 }
 473
 474                 // Page elements
 475                 $pages = array();
 476
 477                 // Report any missing titles
 478                 foreach ( $pageSet->getMissingTitles() as $fakeId => $title ) {
 479                         $vals = array();
 480                         ApiQueryBase::addTitleInfo( $vals, $title );
 481                         $vals['missing'] = '';
 482                         $pages[$fakeId] = $vals;
 483                 }
 484                 // Report any invalid titles
 485                 foreach ( $pageSet->getInvalidTitles() as $fakeId => $title ) {
 486                         $pages[$fakeId] = array( 'title' => $title, 'invalid' => '' );
 487                 }
 488                 // Report any missing page ids
 489                 foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
 490                         $pages[$pageid] = array(
 491                                 'pageid' => $pageid,
 492                                 'missing' => ''
 493                         );
 494                 }
 495                 // Report special pages
 496                 foreach ( $pageSet->getSpecialTitles() as $fakeId => $title ) {
 497                         $vals = array();
 498                         ApiQueryBase::addTitleInfo( $vals, $title );
 499                         $vals['special'] = '';
 500                         if ( $title->isSpecialPage() &&
 501                                         !SpecialPageFactory::exists( $title->getDbKey() ) ) {
 502                                 $vals['missing'] = '';
 503                         } elseif ( $title->getNamespace() == NS_MEDIA &&
 504                                         !wfFindFile( $title ) ) {
 505                                 $vals['missing'] = '';
 506                         }
 507                         $pages[$fakeId] = $vals;
 508                 }
 509
 510                 // Output general page information for found titles
 511                 foreach ( $pageSet->getGoodTitles() as $pageid => $title ) {
 512                         $vals = array();
 513                         $vals['pageid'] = $pageid;
 514                         ApiQueryBase::addTitleInfo( $vals, $title );
 515                         $pages[$pageid] = $vals;
 516                 }
 517
 518                 if ( count( $pages ) ) {
 519                         if ( $this->params['indexpageids'] ) {
 520                                 $pageIDs = array_keys( $pages );
 521                                 // json treats all map keys as strings - converting to match
 522                                 $pageIDs = array_map( 'strval', $pageIDs );
 523                                 $result->setIndexedTagName( $pageIDs, 'id' );
 524                                 $result->addValue( 'query', 'pageids', $pageIDs );
 525                         }
 526
 527                         $result->setIndexedTagName( $pages, 'page' );
 528                         $result->addValue( 'query', 'pages', $pages );
 529                 }
 530                 if ( $this->params['export'] ) {
 531                         $this->doExport( $pageSet, $result );
 532                 }
 533         }
 534
 535         /**
 536          * @param  $pageSet ApiPageSet Pages to be exported
 537          * @param  $result ApiResult Result to output to
 538          */
 539         private function doExport( $pageSet, $result ) {
 540                 $exportTitles = array();
 541                 $titles = $pageSet->getGoodTitles();
 542                 if ( count( $titles ) ) {
 543                         $user = $this->getUser();
 544                         foreach ( $titles as $title ) {
 545                                 if ( $title->userCan( 'read', $user ) ) {
 546                                         $exportTitles[] = $title;
 547                                 }
 548                         }
 549                 }
 550
 551                 $exporter = new WikiExporter( $this->getDB() );
 552                 // WikiExporter writes to stdout, so catch its
 553                 // output with an ob
 554                 ob_start();
 555                 $exporter->openStream();
 556                 foreach ( $exportTitles as $title ) {
 557                         $exporter->pageByTitle( $title );
 558                 }
 559                 $exporter->closeStream();
 560                 $exportxml = ob_get_contents();
 561                 ob_end_clean();
 562
 563                 // Don't check the size of exported stuff
 564                 // It's not continuable, so it would cause more
 565                 // problems than it'd solve
 566                 $result->disableSizeCheck();
 567                 if ( $this->params['exportnowrap'] ) {
 568                         $result->reset();
 569                         // Raw formatter will handle this
 570                         $result->addValue( null, 'text', $exportxml );
 571                         $result->addValue( null, 'mime', 'text/xml' );
 572                 } else {
 573                         $r = array();
 574                         ApiResult::setContent( $r, $exportxml );
 575                         $result->addValue( 'query', 'export', $r );
 576                 }
 577                 $result->enableSizeCheck();
 578         }
 579
 580         /**
 581          * Create a generator object of the given type and return it
 582          * @param $generatorName string Module name
 583          * @return ApiQueryGeneratorBase
 584          */
 585         public function newGenerator( $generatorName ) {
 586                 $generator = $this->mModuleMgr->getModule( $generatorName, null, true );
 587                 if ( $generator === null ) {
 588                         $this->dieUsage( "Unknown generator=$generatorName", 'badgenerator' );
 589                 }
 590                 if ( !$generator instanceof ApiQueryGeneratorBase ) {
 591                         $this->dieUsage( "Module $generatorName cannot be used as a generator", 'badgenerator' );
 592                 }
 593                 $generator->setGeneratorMode();
 594                 return $generator;
 595         }
 596
 597         /**
 598          * For generator mode, execute generator, and use its output as new
 599          * ApiPageSet
 600          * @param $generator ApiQueryGeneratorBase Generator Module
 601          * @param $modules array of module objects
 602          */
 603         protected function executeGeneratorModule( $generator, $modules ) {
 604                 // Generator results
 605                 $resultPageSet = new ApiPageSet( $this, $this->redirects, $this->convertTitles );
 606
 607                 // Add any additional fields modules may need
 608                 $generator->requestExtraData( $this->mPageSet );
 609                 $this->addCustomFldsToPageSet( $modules, $resultPageSet );
 610
 611                 // Populate page information with the original user input
 612                 $this->mPageSet->execute();
 613
 614                 // populate resultPageSet with the generator output
 615                 $generator->profileIn();
 616                 $generator->executeGenerator( $resultPageSet );
 617                 wfRunHooks( 'APIQueryGeneratorAfterExecute', array( &$generator, &$resultPageSet ) );
 618                 $resultPageSet->finishPageSetGeneration();
 619                 $generator->profileOut();
 620
 621                 // Swap the resulting pageset back in
 622                 $this->mPageSet = $resultPageSet;
 623         }
 624
 625         public function getAllowedParams() {
 626                 return array(
 627                         'prop' => array(
 628                                 ApiBase::PARAM_ISMULTI => true,
 629                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'prop' )
 630                         ),
 631                         'list' => array(
 632                                 ApiBase::PARAM_ISMULTI => true,
 633                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'list' )
 634                         ),
 635                         'meta' => array(
 636                                 ApiBase::PARAM_ISMULTI => true,
 637                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'meta' )
 638                         ),
 639                         'generator' => array(
 640                                 ApiBase::PARAM_TYPE => $this->mAllowedGenerators
 641                         ),
 642                         'redirects' => false,
 643                         'converttitles' => false,
 644                         'indexpageids' => false,
 645                         'export' => false,
 646                         'exportnowrap' => false,
 647                         'iwurl' => false,
 648                 );
 649         }
 650
 651         /**
 652          * Override the parent to generate help messages for all available query modules.
 653          * @return string
 654          */
 655         public function makeHelpMsg() {
 656                 // Make sure the internal object is empty
 657                 // (just in case a sub-module decides to optimize during instantiation)
 658                 $this->mPageSet = null;
 659
 660                 $querySeparator = str_repeat( '--- ', 12 );
 661                 $moduleSeparator = str_repeat( '*** ', 14 );
 662                 $msg = "\n$querySeparator Query: Prop  $querySeparator\n\n";
 663                 $msg .= $this->makeHelpMsgHelper( 'prop' );
 664                 $msg .= "\n$querySeparator Query: List  $querySeparator\n\n";
 665                 $msg .= $this->makeHelpMsgHelper( 'list' );
 666                 $msg .= "\n$querySeparator Query: Meta  $querySeparator\n\n";
 667                 $msg .= $this->makeHelpMsgHelper( 'meta' );
 668                 $msg .= "\n\n$moduleSeparator Modules: continuation  $moduleSeparator\n\n";
 669
 670                 // Use parent to make default message for the query module
 671                 $msg = parent::makeHelpMsg() . $msg;
 672
 673                 return $msg;
 674         }
 675
 676         /**
 677          * For all modules of a given group, generate help messages and join them together
 678          * @param $group string Module group
 679          * @return string
 680          */
 681         private function makeHelpMsgHelper( $group ) {
 682                 $moduleDescriptions = array();
 683
 684                 $moduleNames = $this->mModuleMgr->getNames( $group );
 685                 sort( $moduleNames );
 686                 foreach ( $moduleNames as $name ) {
 687                         /**
 688                          * @var $module ApiQueryBase
 689                          */
 690                         $module = $this->mModuleMgr->getModule( $name );
 691
 692                         $msg = ApiMain::makeHelpMsgHeader( $module, $group );
 693                         $msg2 = $module->makeHelpMsg();
 694                         if ( $msg2 !== false ) {
 695                                 $msg .= $msg2;
 696                         }
 697                         if ( $module instanceof ApiQueryGeneratorBase ) {
 698                                 $msg .= "Generator:\n  This module may be used as a generator\n";
 699                         }
 700                         $moduleDescriptions[] = $msg;
 701                 }
 702
 703                 return implode( "\n", $moduleDescriptions );
 704         }
 705
 706         /**
 707          * Override to add extra parameters from PageSet
 708          * @return string
 709          */
 710         public function makeHelpMsgParameters() {
 711                 $psModule = new ApiPageSet( $this );
 712                 return $psModule->makeHelpMsgParameters() . parent::makeHelpMsgParameters();
 713         }
 714
 715         public function shouldCheckMaxlag() {
 716                 return true;
 717         }
 718
 719         public function getParamDescription() {
 720                 return array(
 721                         'prop' => 'Which properties to get for the titles/revisions/pageids. Module help is available below',
 722                         'list' => 'Which lists to get. Module help is available below',
 723                         'meta' => 'Which metadata to get about the site. Module help is available below',
 724                         'generator' => array( 'Use the output of a list as the input for other prop/list/meta items',
 725                                         'NOTE: generator parameter names must be prefixed with a \'g\', see examples' ),
 726                         'redirects' => 'Automatically resolve redirects',
 727                         'converttitles' => array( "Convert titles to other variants if necessary. Only works if the wiki's content language supports variant conversion.",
 728                                         'Languages that support variant conversion include ' . implode( ', ', LanguageConverter::$languagesWithVariants ) ),
 729                         'indexpageids' => 'Include an additional pageids section listing all returned page IDs',
 730                         'export' => 'Export the current revisions of all given or generated pages',
 731                         'exportnowrap' => 'Return the export XML without wrapping it in an XML result (same format as Special:Export). Can only be used with export',
 732                         'iwurl' => 'Whether to get the full URL if the title is an interwiki link',
 733                 );
 734         }
 735
 736         public function getDescription() {
 737                 return array(
 738                         'Query API module allows applications to get needed pieces of data from the MediaWiki databases,',
 739                         'and is loosely based on the old query.php interface.',
 740                         'All data modifications will first have to use query to acquire a token to prevent abuse from malicious sites'
 741                 );
 742         }
 743
 744         public function getPossibleErrors() {
 745                 return array_merge( parent::getPossibleErrors(), array(
 746                         array( 'code' => 'badgenerator', 'info' => 'Module $generatorName cannot be used as a generator' ),
 747                 ) );
 748         }
 749
 750         public function getExamples() {
 751                 return array(
 752                         'api.php?action=query&prop=revisions&meta=siteinfo&titles=Main%20Page&rvprop=user|comment',
 753                         'api.php?action=query&generator=allpages&gapprefix=API/&prop=revisions',
 754                 );
 755         }
 756
 757         public function getHelpUrls() {
 758                 return array(
 759                         'https://www.mediawiki.org/wiki/API:Meta',
 760                         'https://www.mediawiki.org/wiki/API:Properties',
 761                         'https://www.mediawiki.org/wiki/API:Lists',
 762                 );
 763         }
 764 }