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                 'contributors' => 'ApiQueryContributors',
  48                 'deletedrevisions' => 'ApiQueryDeletedRevisions',
  49                 'duplicatefiles' => 'ApiQueryDuplicateFiles',
  50                 'extlinks' => 'ApiQueryExternalLinks',
  51                 'fileusage' => 'ApiQueryBacklinksprop',
  52                 'images' => 'ApiQueryImages',
  53                 'imageinfo' => 'ApiQueryImageInfo',
  54                 'info' => 'ApiQueryInfo',
  55                 'links' => 'ApiQueryLinks',
  56                 'linkshere' => 'ApiQueryBacklinksprop',
  57                 'iwlinks' => 'ApiQueryIWLinks',
  58                 'langlinks' => 'ApiQueryLangLinks',
  59                 'pageprops' => 'ApiQueryPageProps',
  60                 'redirects' => 'ApiQueryBacklinksprop',
  61                 'revisions' => 'ApiQueryRevisions',
  62                 'stashimageinfo' => 'ApiQueryStashImageInfo',
  63                 'templates' => 'ApiQueryLinks',
  64                 'transcludedin' => 'ApiQueryBacklinksprop',
  65         );
  66
  67         /**
  68          * List of Api Query list modules
  69          * @var array
  70          */
  71         private static $QueryListModules = array(
  72                 'allcategories' => 'ApiQueryAllCategories',
  73                 'alldeletedrevisions' => 'ApiQueryAllDeletedRevisions',
  74                 'allfileusages' => 'ApiQueryAllLinks',
  75                 'allimages' => 'ApiQueryAllImages',
  76                 'alllinks' => 'ApiQueryAllLinks',
  77                 'allpages' => 'ApiQueryAllPages',
  78                 'allredirects' => 'ApiQueryAllLinks',
  79                 'alltransclusions' => 'ApiQueryAllLinks',
  80                 'allusers' => 'ApiQueryAllUsers',
  81                 'backlinks' => 'ApiQueryBacklinks',
  82                 'blocks' => 'ApiQueryBlocks',
  83                 'categorymembers' => 'ApiQueryCategoryMembers',
  84                 'deletedrevs' => 'ApiQueryDeletedrevs',
  85                 'embeddedin' => 'ApiQueryBacklinks',
  86                 'exturlusage' => 'ApiQueryExtLinksUsage',
  87                 'filearchive' => 'ApiQueryFilearchive',
  88                 'imageusage' => 'ApiQueryBacklinks',
  89                 'iwbacklinks' => 'ApiQueryIWBacklinks',
  90                 'langbacklinks' => 'ApiQueryLangBacklinks',
  91                 'logevents' => 'ApiQueryLogEvents',
  92                 'pageswithprop' => 'ApiQueryPagesWithProp',
  93                 'pagepropnames' => 'ApiQueryPagePropNames',
  94                 'prefixsearch' => 'ApiQueryPrefixSearch',
  95                 'protectedtitles' => 'ApiQueryProtectedTitles',
  96                 'querypage' => 'ApiQueryQueryPage',
  97                 'random' => 'ApiQueryRandom',
  98                 'recentchanges' => 'ApiQueryRecentChanges',
  99                 'search' => 'ApiQuerySearch',
 100                 'tags' => 'ApiQueryTags',
 101                 'usercontribs' => 'ApiQueryContributions',
 102                 'users' => 'ApiQueryUsers',
 103                 'watchlist' => 'ApiQueryWatchlist',
 104                 'watchlistraw' => 'ApiQueryWatchlistRaw',
 105         );
 106
 107         /**
 108          * List of Api Query meta modules
 109          * @var array
 110          */
 111         private static $QueryMetaModules = array(
 112                 'allmessages' => 'ApiQueryAllMessages',
 113                 'siteinfo' => 'ApiQuerySiteinfo',
 114                 'userinfo' => 'ApiQueryUserInfo',
 115                 'filerepoinfo' => 'ApiQueryFileRepoInfo',
 116                 'tokens' => 'ApiQueryTokens',
 117         );
 118
 119         /**
 120          * @var ApiPageSet
 121          */
 122         private $mPageSet;
 123
 124         private $mParams;
 125         private $mNamedDB = array();
 126         private $mModuleMgr;
 127
 128         /**
 129          * @param ApiMain $main
 130          * @param string $action
 131          */
 132         public function __construct( ApiMain $main, $action ) {
 133                 parent::__construct( $main, $action );
 134
 135                 $this->mModuleMgr = new ApiModuleManager( $this );
 136
 137                 // Allow custom modules to be added in LocalSettings.php
 138                 $config = $this->getConfig();
 139                 $this->mModuleMgr->addModules( self::$QueryPropModules, 'prop' );
 140                 $this->mModuleMgr->addModules( $config->get( 'APIPropModules' ), 'prop' );
 141                 $this->mModuleMgr->addModules( self::$QueryListModules, 'list' );
 142                 $this->mModuleMgr->addModules( $config->get( 'APIListModules' ), 'list' );
 143                 $this->mModuleMgr->addModules( self::$QueryMetaModules, 'meta' );
 144                 $this->mModuleMgr->addModules( $config->get( 'APIMetaModules' ), 'meta' );
 145
 146                 Hooks::run( 'ApiQuery::moduleManager', array( $this->mModuleMgr ) );
 147
 148                 // Create PageSet that will process titles/pageids/revids/generator
 149                 $this->mPageSet = new ApiPageSet( $this );
 150         }
 151
 152         /**
 153          * Overrides to return this instance's module manager.
 154          * @return ApiModuleManager
 155          */
 156         public function getModuleManager() {
 157                 return $this->mModuleMgr;
 158         }
 159
 160         /**
 161          * Get the query database connection with the given name.
 162          * If no such connection has been requested before, it will be created.
 163          * Subsequent calls with the same $name will return the same connection
 164          * as the first, regardless of the values of $db and $groups
 165          * @param string $name Name to assign to the database connection
 166          * @param int $db One of the DB_* constants
 167          * @param array $groups Query groups
 168          * @return DatabaseBase
 169          */
 170         public function getNamedDB( $name, $db, $groups ) {
 171                 if ( !array_key_exists( $name, $this->mNamedDB ) ) {
 172                         $this->mNamedDB[$name] = wfGetDB( $db, $groups );
 173                 }
 174
 175                 return $this->mNamedDB[$name];
 176         }
 177
 178         /**
 179          * Gets the set of pages the user has requested (or generated)
 180          * @return ApiPageSet
 181          */
 182         public function getPageSet() {
 183                 return $this->mPageSet;
 184         }
 185
 186         /**
 187          * Get the array mapping module names to class names
 188          * @deprecated since 1.21, use getModuleManager()'s methods instead
 189          * @return array Array(modulename => classname)
 190          */
 191         public function getModules() {
 192                 wfDeprecated( __METHOD__, '1.21' );
 193
 194                 return $this->getModuleManager()->getNamesWithClasses();
 195         }
 196
 197         /**
 198          * Get the generators array mapping module names to class names
 199          * @deprecated since 1.21, list of generators is maintained by ApiPageSet
 200          * @return array Array(modulename => classname)
 201          */
 202         public function getGenerators() {
 203                 wfDeprecated( __METHOD__, '1.21' );
 204                 $gens = array();
 205                 foreach ( $this->mModuleMgr->getNamesWithClasses() as $name => $class ) {
 206                         if ( is_subclass_of( $class, 'ApiQueryGeneratorBase' ) ) {
 207                                 $gens[$name] = $class;
 208                         }
 209                 }
 210
 211                 return $gens;
 212         }
 213
 214         /**
 215          * Get whether the specified module is a prop, list or a meta query module
 216          * @deprecated since 1.21, use getModuleManager()->getModuleGroup()
 217          * @param string $moduleName Name of the module to find type for
 218          * @return string|null
 219          */
 220         function getModuleType( $moduleName ) {
 221                 return $this->getModuleManager()->getModuleGroup( $moduleName );
 222         }
 223
 224         /**
 225          * @return ApiFormatRaw|null
 226          */
 227         public function getCustomPrinter() {
 228                 // If &exportnowrap is set, use the raw formatter
 229                 if ( $this->getParameter( 'export' ) &&
 230                         $this->getParameter( 'exportnowrap' )
 231                 ) {
 232                         return new ApiFormatRaw( $this->getMain(),
 233                                 $this->getMain()->createPrinterByName( 'xml' ) );
 234                 } else {
 235                         return null;
 236                 }
 237         }
 238
 239         /**
 240          * Query execution happens in the following steps:
 241          * #1 Create a PageSet object with any pages requested by the user
 242          * #2 If using a generator, execute it to get a new ApiPageSet object
 243          * #3 Instantiate all requested modules.
 244          *    This way the PageSet object will know what shared data is required,
 245          *    and minimize DB calls.
 246          * #4 Output all normalization and redirect resolution information
 247          * #5 Execute all requested modules
 248          */
 249         public function execute() {
 250                 $this->mParams = $this->extractRequestParams();
 251
 252                 // Instantiate requested modules
 253                 $allModules = array();
 254                 $this->instantiateModules( $allModules, 'prop' );
 255                 $propModules = array_keys( $allModules );
 256                 $this->instantiateModules( $allModules, 'list' );
 257                 $this->instantiateModules( $allModules, 'meta' );
 258
 259                 // Filter modules based on continue parameter
 260                 $continuationManager = new ApiContinuationManager( $this, $allModules, $propModules );
 261                 $this->setContinuationManager( $continuationManager );
 262                 $modules = $continuationManager->getRunModules();
 263
 264                 if ( !$continuationManager->isGeneratorDone() ) {
 265                         // Query modules may optimize data requests through the $this->getPageSet()
 266                         // object by adding extra fields from the page table.
 267                         foreach ( $modules as $module ) {
 268                                 $module->requestExtraData( $this->mPageSet );
 269                         }
 270                         // Populate page/revision information
 271                         $this->mPageSet->execute();
 272                         // Record page information (title, namespace, if exists, etc)
 273                         $this->outputGeneralPageInfo();
 274                 } else {
 275                         $this->mPageSet->executeDryRun();
 276                 }
 277
 278                 $cacheMode = $this->mPageSet->getCacheMode();
 279                 $stats =  $this->getContext()->getStats();
 280
 281                 // Execute all unfinished modules
 282                 /** @var $module ApiQueryBase */
 283                 foreach ( $modules as $module ) {
 284                         $params = $module->extractRequestParams();
 285                         $cacheMode = $this->mergeCacheMode(
 286                                 $cacheMode, $module->getCacheMode( $params ) );
 287
 288                         $statsPath = 'api.modules.' . strtr( $module->getModulePath(), '+', '.' );
 289                         $metric = $stats->increment( $statsPath );
 290                         $metric->setSampleRate( 0.001 );
 291
 292                         $module->execute();
 293                         Hooks::run( 'APIQueryAfterExecute', array( &$module ) );
 294                 }
 295
 296                 // Set the cache mode
 297                 $this->getMain()->setCacheMode( $cacheMode );
 298
 299                 // Write the continuation data into the result
 300                 $this->setContinuationManager( null );
 301                 if ( $this->mParams['rawcontinue'] ) {
 302                         $data = $continuationManager->getRawContinuation();
 303                         if ( $data ) {
 304                                 $this->getResult()->addValue( null, 'query-continue', $data,
 305                                         ApiResult::ADD_ON_TOP | ApiResult::NO_SIZE_CHECK );
 306                         }
 307                 } else {
 308                         $continuationManager->setContinuationIntoResult( $this->getResult() );
 309                 }
 310
 311                 /// @todo: Remove this after a suitable period of time. When REL1_26 is cut, if not before.
 312                 if ( $this->mParams['continue'] === null && !$this->mParams['rawcontinue'] &&
 313                         $this->getResult()->getResultData( 'continue' ) !== null
 314                 ) {
 315                         $this->setWarning(
 316                                 'Formatting of continuation data has changed. ' .
 317                                 'To receive raw query-continue data, use the \'rawcontinue\' parameter. ' .
 318                                 'To silence this warning, pass an empty string for \'continue\' in the initial query.'
 319                         );
 320                 }
 321         }
 322
 323         /**
 324          * Update a cache mode string, applying the cache mode of a new module to it.
 325          * The cache mode may increase in the level of privacy, but public modules
 326          * added to private data do not decrease the level of privacy.
 327          *
 328          * @param string $cacheMode
 329          * @param string $modCacheMode
 330          * @return string
 331          */
 332         protected function mergeCacheMode( $cacheMode, $modCacheMode ) {
 333                 if ( $modCacheMode === 'anon-public-user-private' ) {
 334                         if ( $cacheMode !== 'private' ) {
 335                                 $cacheMode = 'anon-public-user-private';
 336                         }
 337                 } elseif ( $modCacheMode === 'public' ) {
 338                         // do nothing, if it's public already it will stay public
 339                 } else { // private
 340                         $cacheMode = 'private';
 341                 }
 342
 343                 return $cacheMode;
 344         }
 345
 346         /**
 347          * Create instances of all modules requested by the client
 348          * @param array $modules To append instantiated modules to
 349          * @param string $param Parameter name to read modules from
 350          */
 351         private function instantiateModules( &$modules, $param ) {
 352                 $wasPosted = $this->getRequest()->wasPosted();
 353                 if ( isset( $this->mParams[$param] ) ) {
 354                         foreach ( $this->mParams[$param] as $moduleName ) {
 355                                 $instance = $this->mModuleMgr->getModule( $moduleName, $param );
 356                                 if ( $instance === null ) {
 357                                         ApiBase::dieDebug( __METHOD__, 'Error instantiating module' );
 358                                 }
 359                                 if ( !$wasPosted && $instance->mustBePosted() ) {
 360                                         $this->dieUsageMsgOrDebug( array( 'mustbeposted', $moduleName ) );
 361                                 }
 362                                 // Ignore duplicates. TODO 2.0: die()?
 363                                 if ( !array_key_exists( $moduleName, $modules ) ) {
 364                                         $modules[$moduleName] = $instance;
 365                                 }
 366                         }
 367                 }
 368         }
 369
 370         /**
 371          * Appends an element for each page in the current pageSet with the
 372          * most general information (id, title), plus any title normalizations
 373          * and missing or invalid title/pageids/revids.
 374          */
 375         private function outputGeneralPageInfo() {
 376                 $pageSet = $this->getPageSet();
 377                 $result = $this->getResult();
 378
 379                 // We can't really handle max-result-size failure here, but we need to
 380                 // check anyway in case someone set the limit stupidly low.
 381                 $fit = true;
 382
 383                 $values = $pageSet->getNormalizedTitlesAsResult( $result );
 384                 if ( $values ) {
 385                         $fit = $fit && $result->addValue( 'query', 'normalized', $values );
 386                 }
 387                 $values = $pageSet->getConvertedTitlesAsResult( $result );
 388                 if ( $values ) {
 389                         $fit = $fit && $result->addValue( 'query', 'converted', $values );
 390                 }
 391                 $values = $pageSet->getInterwikiTitlesAsResult( $result, $this->mParams['iwurl'] );
 392                 if ( $values ) {
 393                         $fit = $fit && $result->addValue( 'query', 'interwiki', $values );
 394                 }
 395                 $values = $pageSet->getRedirectTitlesAsResult( $result );
 396                 if ( $values ) {
 397                         $fit = $fit && $result->addValue( 'query', 'redirects', $values );
 398                 }
 399                 $values = $pageSet->getMissingRevisionIDsAsResult( $result );
 400                 if ( $values ) {
 401                         $fit = $fit && $result->addValue( 'query', 'badrevids', $values );
 402                 }
 403
 404                 // Page elements
 405                 $pages = array();
 406
 407                 // Report any missing titles
 408                 foreach ( $pageSet->getMissingTitles() as $fakeId => $title ) {
 409                         $vals = array();
 410                         ApiQueryBase::addTitleInfo( $vals, $title );
 411                         $vals['missing'] = true;
 412                         $pages[$fakeId] = $vals;
 413                 }
 414                 // Report any invalid titles
 415                 foreach ( $pageSet->getInvalidTitlesAndReasons() as $fakeId => $data ) {
 416                         $pages[$fakeId] = $data + array( 'invalid' => true );
 417                 }
 418                 // Report any missing page ids
 419                 foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
 420                         $pages[$pageid] = array(
 421                                 'pageid' => $pageid,
 422                                 'missing' => true
 423                         );
 424                 }
 425                 // Report special pages
 426                 /** @var $title Title */
 427                 foreach ( $pageSet->getSpecialTitles() as $fakeId => $title ) {
 428                         $vals = array();
 429                         ApiQueryBase::addTitleInfo( $vals, $title );
 430                         $vals['special'] = true;
 431                         if ( $title->isSpecialPage() &&
 432                                 !SpecialPageFactory::exists( $title->getDBkey() )
 433                         ) {
 434                                 $vals['missing'] = true;
 435                         } elseif ( $title->getNamespace() == NS_MEDIA &&
 436                                 !wfFindFile( $title )
 437                         ) {
 438                                 $vals['missing'] = true;
 439                         }
 440                         $pages[$fakeId] = $vals;
 441                 }
 442
 443                 // Output general page information for found titles
 444                 foreach ( $pageSet->getGoodTitles() as $pageid => $title ) {
 445                         $vals = array();
 446                         $vals['pageid'] = $pageid;
 447                         ApiQueryBase::addTitleInfo( $vals, $title );
 448                         $pages[$pageid] = $vals;
 449                 }
 450
 451                 if ( count( $pages ) ) {
 452                         $pageSet->populateGeneratorData( $pages );
 453                         ApiResult::setArrayType( $pages, 'BCarray' );
 454
 455                         if ( $this->mParams['indexpageids'] ) {
 456                                 $pageIDs = array_keys( ApiResult::stripMetadataNonRecursive( $pages ) );
 457                                 // json treats all map keys as strings - converting to match
 458                                 $pageIDs = array_map( 'strval', $pageIDs );
 459                                 ApiResult::setIndexedTagName( $pageIDs, 'id' );
 460                                 $fit = $fit && $result->addValue( 'query', 'pageids', $pageIDs );
 461                         }
 462
 463                         ApiResult::setIndexedTagName( $pages, 'page' );
 464                         $fit = $fit && $result->addValue( 'query', 'pages', $pages );
 465                 }
 466
 467                 if ( !$fit ) {
 468                         $this->dieUsage(
 469                                 'The value of $wgAPIMaxResultSize on this wiki is ' .
 470                                         'too small to hold basic result information',
 471                                 'badconfig'
 472                         );
 473                 }
 474
 475                 if ( $this->mParams['export'] ) {
 476                         $this->doExport( $pageSet, $result );
 477                 }
 478         }
 479
 480         /**
 481          * This method is called by the generator base when generator in the smart-continue
 482          * mode tries to set 'query-continue' value. ApiQuery stores those values separately
 483          * until the post-processing when it is known if the generation should continue or repeat.
 484          * @deprecated since 1.24
 485          * @param ApiQueryGeneratorBase $module Generator module
 486          * @param string $paramName
 487          * @param mixed $paramValue
 488          * @return bool True if processed, false if this is a legacy continue
 489          */
 490         public function setGeneratorContinue( $module, $paramName, $paramValue ) {
 491                 wfDeprecated( __METHOD__, '1.24' );
 492                 $this->getContinuationManager()->addGeneratorContinueParam( $module, $paramName, $paramValue );
 493                 return !$this->getParameter( 'rawcontinue' );
 494         }
 495
 496         /**
 497          * @param ApiPageSet $pageSet Pages to be exported
 498          * @param ApiResult $result Result to output to
 499          */
 500         private function doExport( $pageSet, $result ) {
 501                 $exportTitles = array();
 502                 $titles = $pageSet->getGoodTitles();
 503                 if ( count( $titles ) ) {
 504                         $user = $this->getUser();
 505                         /** @var $title Title */
 506                         foreach ( $titles as $title ) {
 507                                 if ( $title->userCan( 'read', $user ) ) {
 508                                         $exportTitles[] = $title;
 509                                 }
 510                         }
 511                 }
 512
 513                 $exporter = new WikiExporter( $this->getDB() );
 514                 // WikiExporter writes to stdout, so catch its
 515                 // output with an ob
 516                 ob_start();
 517                 $exporter->openStream();
 518                 foreach ( $exportTitles as $title ) {
 519                         $exporter->pageByTitle( $title );
 520                 }
 521                 $exporter->closeStream();
 522                 $exportxml = ob_get_contents();
 523                 ob_end_clean();
 524
 525                 // Don't check the size of exported stuff
 526                 // It's not continuable, so it would cause more
 527                 // problems than it'd solve
 528                 if ( $this->mParams['exportnowrap'] ) {
 529                         $result->reset();
 530                         // Raw formatter will handle this
 531                         $result->addValue( null, 'text', $exportxml, ApiResult::NO_SIZE_CHECK );
 532                         $result->addValue( null, 'mime', 'text/xml', ApiResult::NO_SIZE_CHECK );
 533                 } else {
 534                         $result->addValue( 'query', 'export', $exportxml, ApiResult::NO_SIZE_CHECK );
 535                         $result->addValue( 'query', ApiResult::META_BC_SUBELEMENTS, array( 'export' ) );
 536                 }
 537         }
 538
 539         public function getAllowedParams( $flags = 0 ) {
 540                 $result = array(
 541                         'prop' => array(
 542                                 ApiBase::PARAM_ISMULTI => true,
 543                                 ApiBase::PARAM_TYPE => 'submodule',
 544                         ),
 545                         'list' => array(
 546                                 ApiBase::PARAM_ISMULTI => true,
 547                                 ApiBase::PARAM_TYPE => 'submodule',
 548                         ),
 549                         'meta' => array(
 550                                 ApiBase::PARAM_ISMULTI => true,
 551                                 ApiBase::PARAM_TYPE => 'submodule',
 552                         ),
 553                         'indexpageids' => false,
 554                         'export' => false,
 555                         'exportnowrap' => false,
 556                         'iwurl' => false,
 557                         'continue' => array(
 558                                 ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
 559                         ),
 560                         'rawcontinue' => false,
 561                 );
 562                 if ( $flags ) {
 563                         $result += $this->getPageSet()->getFinalParams( $flags );
 564                 }
 565
 566                 return $result;
 567         }
 568
 569         /**
 570          * Override the parent to generate help messages for all available query modules.
 571          * @deprecated since 1.25
 572          * @return string
 573          */
 574         public function makeHelpMsg() {
 575                 wfDeprecated( __METHOD__, '1.25' );
 576
 577                 // Use parent to make default message for the query module
 578                 $msg = parent::makeHelpMsg();
 579
 580                 $querySeparator = str_repeat( '--- ', 12 );
 581                 $moduleSeparator = str_repeat( '*** ', 14 );
 582                 $msg .= "\n$querySeparator Query: Prop  $querySeparator\n\n";
 583                 $msg .= $this->makeHelpMsgHelper( 'prop' );
 584                 $msg .= "\n$querySeparator Query: List  $querySeparator\n\n";
 585                 $msg .= $this->makeHelpMsgHelper( 'list' );
 586                 $msg .= "\n$querySeparator Query: Meta  $querySeparator\n\n";
 587                 $msg .= $this->makeHelpMsgHelper( 'meta' );
 588                 $msg .= "\n\n$moduleSeparator Modules: continuation  $moduleSeparator\n\n";
 589
 590                 return $msg;
 591         }
 592
 593         /**
 594          * For all modules of a given group, generate help messages and join them together
 595          * @deprecated since 1.25
 596          * @param string $group Module group
 597          * @return string
 598          */
 599         private function makeHelpMsgHelper( $group ) {
 600                 $moduleDescriptions = array();
 601
 602                 $moduleNames = $this->mModuleMgr->getNames( $group );
 603                 sort( $moduleNames );
 604                 foreach ( $moduleNames as $name ) {
 605                         /**
 606                          * @var $module ApiQueryBase
 607                          */
 608                         $module = $this->mModuleMgr->getModule( $name );
 609
 610                         $msg = ApiMain::makeHelpMsgHeader( $module, $group );
 611                         $msg2 = $module->makeHelpMsg();
 612                         if ( $msg2 !== false ) {
 613                                 $msg .= $msg2;
 614                         }
 615                         if ( $module instanceof ApiQueryGeneratorBase ) {
 616                                 $msg .= "Generator:\n  This module may be used as a generator\n";
 617                         }
 618                         $moduleDescriptions[] = $msg;
 619                 }
 620
 621                 return implode( "\n", $moduleDescriptions );
 622         }
 623
 624         public function shouldCheckMaxlag() {
 625                 return true;
 626         }
 627
 628         protected function getExamplesMessages() {
 629                 return array(
 630                         'action=query&prop=revisions&meta=siteinfo&' .
 631                                 'titles=Main%20Page&rvprop=user|comment&continue='
 632                                 => 'apihelp-query-example-revisions',
 633                         'action=query&generator=allpages&gapprefix=API/&prop=revisions&continue='
 634                                 => 'apihelp-query-example-allpages',
 635                 );
 636         }
 637
 638         public function getHelpUrls() {
 639                 return array(
 640                         'https://www.mediawiki.org/wiki/API:Query',
 641                         'https://www.mediawiki.org/wiki/API:Meta',
 642                         'https://www.mediawiki.org/wiki/API:Properties',
 643                         'https://www.mediawiki.org/wiki/API:Lists',
 644                 );
 645         }
 646 }