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                 'pageswithprop' => 'ApiQueryPagesWithProp',
  84                 'pagepropnames' => 'ApiQueryPagePropNames',
  85                 'protectedtitles' => 'ApiQueryProtectedTitles',
  86                 'querypage' => 'ApiQueryQueryPage',
  87                 'random' => 'ApiQueryRandom',
  88                 'recentchanges' => 'ApiQueryRecentChanges',
  89                 'search' => 'ApiQuerySearch',
  90                 'tags' => 'ApiQueryTags',
  91                 'usercontribs' => 'ApiQueryContributions',
  92                 'users' => 'ApiQueryUsers',
  93                 'watchlist' => 'ApiQueryWatchlist',
  94                 'watchlistraw' => 'ApiQueryWatchlistRaw',
  95         );
  96
  97         /**
  98          * List of Api Query meta modules
  99          * @var array
 100          */
 101         private static $QueryMetaModules = array(
 102                 'allmessages' => 'ApiQueryAllMessages',
 103                 'siteinfo' => 'ApiQuerySiteinfo',
 104                 'userinfo' => 'ApiQueryUserInfo',
 105         );
 106
 107         /**
 108          * @var ApiPageSet
 109          */
 110         private $mPageSet;
 111
 112         private $mParams;
 113         private $mNamedDB = array();
 114         private $mModuleMgr;
 115         private $mGeneratorContinue;
 116         private $mUseLegacyContinue;
 117
 118         /**
 119          * @param $main ApiMain
 120          * @param $action string
 121          */
 122         public function __construct( $main, $action ) {
 123                 parent::__construct( $main, $action );
 124
 125                 $this->mModuleMgr = new ApiModuleManager( $this );
 126
 127                 // Allow custom modules to be added in LocalSettings.php
 128                 global $wgAPIPropModules, $wgAPIListModules, $wgAPIMetaModules;
 129                 $this->mModuleMgr->addModules( self::$QueryPropModules, 'prop' );
 130                 $this->mModuleMgr->addModules( $wgAPIPropModules, 'prop' );
 131                 $this->mModuleMgr->addModules( self::$QueryListModules, 'list' );
 132                 $this->mModuleMgr->addModules( $wgAPIListModules, 'list' );
 133                 $this->mModuleMgr->addModules( self::$QueryMetaModules, 'meta' );
 134                 $this->mModuleMgr->addModules( $wgAPIMetaModules, 'meta' );
 135
 136                 // Create PageSet that will process titles/pageids/revids/generator
 137                 $this->mPageSet = new ApiPageSet( $this );
 138         }
 139
 140         /**
 141          * Overrides to return this instance's module manager.
 142          * @return ApiModuleManager
 143          */
 144         public function getModuleManager() {
 145                 return $this->mModuleMgr;
 146         }
 147
 148         /**
 149          * Get the query database connection with the given name.
 150          * If no such connection has been requested before, it will be created.
 151          * Subsequent calls with the same $name will return the same connection
 152          * as the first, regardless of the values of $db and $groups
 153          * @param string $name Name to assign to the database connection
 154          * @param int $db One of the DB_* constants
 155          * @param array $groups Query groups
 156          * @return DatabaseBase
 157          */
 158         public function getNamedDB( $name, $db, $groups ) {
 159                 if ( !array_key_exists( $name, $this->mNamedDB ) ) {
 160                         $this->profileDBIn();
 161                         $this->mNamedDB[$name] = wfGetDB( $db, $groups );
 162                         $this->profileDBOut();
 163                 }
 164                 return $this->mNamedDB[$name];
 165         }
 166
 167         /**
 168          * Gets the set of pages the user has requested (or generated)
 169          * @return ApiPageSet
 170          */
 171         public function getPageSet() {
 172                 return $this->mPageSet;
 173         }
 174
 175         /**
 176          * Get the array mapping module names to class names
 177          * @deprecated since 1.21, use getModuleManager()'s methods instead
 178          * @return array array(modulename => classname)
 179          */
 180         public function getModules() {
 181                 wfDeprecated( __METHOD__, '1.21' );
 182                 return $this->getModuleManager()->getNamesWithClasses();
 183         }
 184
 185         /**
 186          * Get the generators array mapping module names to class names
 187          * @deprecated since 1.21, list of generators is maintained by ApiPageSet
 188          * @return array array(modulename => classname)
 189          */
 190         public function getGenerators() {
 191                 wfDeprecated( __METHOD__, '1.21' );
 192                 $gens = array();
 193                 foreach ( $this->mModuleMgr->getNamesWithClasses() as $name => $class ) {
 194                         if ( is_subclass_of( $class, 'ApiQueryGeneratorBase' ) ) {
 195                                 $gens[$name] = $class;
 196                         }
 197                 }
 198                 return $gens;
 199         }
 200
 201         /**
 202          * Get whether the specified module is a prop, list or a meta query module
 203          * @deprecated since 1.21, use getModuleManager()->getModuleGroup()
 204          * @param string $moduleName Name of the module to find type for
 205          * @return mixed string or null
 206          */
 207         function getModuleType( $moduleName ) {
 208                 return $this->getModuleManager()->getModuleGroup( $moduleName );
 209         }
 210
 211         /**
 212          * @return ApiFormatRaw|null
 213          */
 214         public function getCustomPrinter() {
 215                 // If &exportnowrap is set, use the raw formatter
 216                 if ( $this->getParameter( 'export' ) &&
 217                                 $this->getParameter( 'exportnowrap' ) )
 218                 {
 219                         return new ApiFormatRaw( $this->getMain(),
 220                                 $this->getMain()->createPrinterByName( 'xml' ) );
 221                 } else {
 222                         return null;
 223                 }
 224         }
 225
 226         /**
 227          * Query execution happens in the following steps:
 228          * #1 Create a PageSet object with any pages requested by the user
 229          * #2 If using a generator, execute it to get a new ApiPageSet object
 230          * #3 Instantiate all requested modules.
 231          *    This way the PageSet object will know what shared data is required,
 232          *    and minimize DB calls.
 233          * #4 Output all normalization and redirect resolution information
 234          * #5 Execute all requested modules
 235          */
 236         public function execute() {
 237                 $this->mParams = $this->extractRequestParams();
 238
 239                 // $pagesetParams is a array of parameter names used by the pageset generator
 240                 //   or null if pageset has already finished and is no longer needed
 241                 // $completeModules is a set of complete modules with the name as key
 242                 $this->initContinue( $pagesetParams, $completeModules );
 243
 244                 // Instantiate requested modules
 245                 $allModules = array();
 246                 $this->instantiateModules( $allModules, 'prop' );
 247                 $propModules = $allModules; // Keep a copy
 248                 $this->instantiateModules( $allModules, 'list' );
 249                 $this->instantiateModules( $allModules, 'meta' );
 250
 251                 // Filter modules based on continue parameter
 252                 $modules = $this->initModules( $allModules, $completeModules, $pagesetParams !== null );
 253
 254                 // Execute pageset if in legacy mode or if pageset is not done
 255                 if ( $completeModules === null || $pagesetParams !== null ) {
 256                         // Populate page/revision information
 257                         $this->mPageSet->execute();
 258                         // Record page information (title, namespace, if exists, etc)
 259                         $this->outputGeneralPageInfo();
 260                 } else {
 261                         $this->mPageSet->executeDryRun();
 262                 }
 263
 264                 $cacheMode = $this->mPageSet->getCacheMode();
 265
 266                 // Execute all unfinished modules
 267                 /** @var $module ApiQueryBase */
 268                 foreach ( $modules as $module ) {
 269                         $params = $module->extractRequestParams();
 270                         $cacheMode = $this->mergeCacheMode(
 271                                 $cacheMode, $module->getCacheMode( $params ) );
 272                         $module->profileIn();
 273                         $module->execute();
 274                         wfRunHooks( 'APIQueryAfterExecute', array( &$module ) );
 275                         $module->profileOut();
 276                 }
 277
 278                 // Set the cache mode
 279                 $this->getMain()->setCacheMode( $cacheMode );
 280
 281                 if ( $completeModules === null ) {
 282                         return; // Legacy continue, we are done
 283                 }
 284
 285                 // Reformat query-continue result section
 286                 $result = $this->getResult();
 287                 $qc = $result->getData();
 288                 if ( isset( $qc['query-continue'] ) ) {
 289                         $qc = $qc['query-continue'];
 290                         $result->unsetValue( null, 'query-continue' );
 291                 } elseif ( $this->mGeneratorContinue !== null ) {
 292                         $qc = array();
 293                 } else {
 294                         // no more "continue"s, we are done!
 295                         return;
 296                 }
 297
 298                 // we are done with all the modules that do not have result in query-continue
 299                 $completeModules = array_merge( $completeModules, array_diff_key( $modules, $qc ) );
 300                 if ( $pagesetParams !== null ) {
 301                         // The pageset is still in use, check if all props have finished
 302                         $incompleteProps = array_intersect_key( $propModules, $qc );
 303                         if ( count( $incompleteProps ) > 0 ) {
 304                                 // Properties are not done, continue with the same pageset state - copy current parameters
 305                                 $main = $this->getMain();
 306                                 $contValues = array();
 307                                 foreach ( $pagesetParams as $param ) {
 308                                         // The param name is already prefix-encoded
 309                                         $contValues[$param] = $main->getVal( $param );
 310                                 }
 311                         } elseif ( $this->mGeneratorContinue !== null ) {
 312                                 // Move to the next set of pages produced by pageset, properties need to be restarted
 313                                 $contValues = $this->mGeneratorContinue;
 314                                 $pagesetParams = array_keys( $contValues );
 315                                 $completeModules = array_diff_key( $completeModules, $propModules );
 316                         } else {
 317                                 // Done with the pageset, finish up with the the lists and meta modules
 318                                 $pagesetParams = null;
 319                         }
 320                 }
 321
 322                 $continue = '||' . implode( '|', array_keys( $completeModules ) );
 323                 if ( $pagesetParams !== null ) {
 324                         // list of all pageset parameters to use in the next request
 325                         $continue = implode( '|', $pagesetParams ) . $continue;
 326                 } else {
 327                         // we are done with the pageset
 328                         $contValues = array();
 329                         $continue = '-' . $continue;
 330                 }
 331                 $contValues['continue'] = $continue;
 332                 foreach ( $qc as $qcModule ) {
 333                         foreach ( $qcModule as $qcKey => $qcValue ) {
 334                                 $contValues[$qcKey] = $qcValue;
 335                         }
 336                 }
 337                 $this->getResult()->addValue( null, 'continue', $contValues );
 338         }
 339
 340         /**
 341          * Parse 'continue' parameter into the list of complete modules and a list of generator parameters
 342          * @param array|null $pagesetParams returns list of generator params or null if pageset is done
 343          * @param array|null $completeModules returns list of finished modules (as keys), or null if legacy
 344          */
 345         private function initContinue( &$pagesetParams, &$completeModules ) {
 346                 $pagesetParams = array();
 347                 $continue = $this->mParams['continue'];
 348                 if ( $continue !== null ) {
 349                         $this->mUseLegacyContinue = false;
 350                         if ( $continue !== '' ) {
 351                                 // Format: ' pagesetParam1 | pagesetParam2 || module1 | module2 | module3 | ...
 352                                 // If pageset is done, use '-'
 353                                 $continue = explode( '||', $continue );
 354                                 $this->dieContinueUsageIf( count( $continue ) !== 2 );
 355                                 if ( $continue[0] === '-' ) {
 356                                         $pagesetParams = null; // No need to execute pageset
 357                                 } elseif ( $continue[0] !== '' ) {
 358                                         // list of pageset params that might need to be repeated
 359                                         $pagesetParams = explode( '|', $continue[0] );
 360                                 }
 361                                 $continue = $continue[1];
 362                         }
 363                         if ( $continue !== '' ) {
 364                                 $completeModules = array_flip( explode( '|', $continue ) );
 365                         } else {
 366                                 $completeModules = array();
 367                         }
 368                 } else {
 369                         $this->mUseLegacyContinue = true;
 370                         $completeModules = null;
 371                 }
 372         }
 373
 374         /**
 375          * Validate sub-modules, filter out completed ones, and do requestExtraData()
 376          * @param array $allModules An dict of name=>instance of all modules requested by the client
 377          * @param array|null $completeModules list of finished modules, or null if legacy continue
 378          * @param bool $usePageset True if pageset will be executed
 379          * @return array of modules to be processed during this execution
 380          */
 381         private function initModules( $allModules, $completeModules, $usePageset ) {
 382                 $modules = $allModules;
 383                 $tmp = $completeModules;
 384                 $wasPosted = $this->getRequest()->wasPosted();
 385
 386                 /** @var $module ApiQueryBase */
 387                 foreach ( $allModules as $moduleName => $module ) {
 388                         if ( !$wasPosted && $module->mustBePosted() ) {
 389                                 $this->dieUsageMsgOrDebug( array( 'mustbeposted', $moduleName ) );
 390                         }
 391                         if ( $completeModules !== null && array_key_exists( $moduleName, $completeModules ) ) {
 392                                 // If this module is done, mark all its params as used
 393                                 $module->extractRequestParams();
 394                                 // Make sure this module is not used during execution
 395                                 unset( $modules[$moduleName] );
 396                                 unset( $tmp[$moduleName] );
 397                         } elseif ( $completeModules === null || $usePageset ) {
 398                                 // Query modules may optimize data requests through the $this->getPageSet()
 399                                 // object by adding extra fields from the page table.
 400                                 // This function will gather all the extra request fields from the modules.
 401                                 $module->requestExtraData( $this->mPageSet );
 402                         } else {
 403                                 // Error - this prop module must have finished before generator is done
 404                                 $this->dieContinueUsageIf( $this->mModuleMgr->getModuleGroup( $moduleName ) === 'prop' );
 405                         }
 406                 }
 407                 $this->dieContinueUsageIf( $completeModules !== null && count( $tmp ) !== 0 );
 408                 return $modules;
 409         }
 410
 411         /**
 412          * Update a cache mode string, applying the cache mode of a new module to it.
 413          * The cache mode may increase in the level of privacy, but public modules
 414          * added to private data do not decrease the level of privacy.
 415          *
 416          * @param $cacheMode string
 417          * @param $modCacheMode string
 418          * @return string
 419          */
 420         protected function mergeCacheMode( $cacheMode, $modCacheMode ) {
 421                 if ( $modCacheMode === 'anon-public-user-private' ) {
 422                         if ( $cacheMode !== 'private' ) {
 423                                 $cacheMode = 'anon-public-user-private';
 424                         }
 425                 } elseif ( $modCacheMode === 'public' ) {
 426                         // do nothing, if it's public already it will stay public
 427                 } else { // private
 428                         $cacheMode = 'private';
 429                 }
 430                 return $cacheMode;
 431         }
 432
 433         /**
 434          * Create instances of all modules requested by the client
 435          * @param array $modules to append instantiated modules to
 436          * @param string $param Parameter name to read modules from
 437          */
 438         private function instantiateModules( &$modules, $param ) {
 439                 if ( isset( $this->mParams[$param] ) ) {
 440                         foreach ( $this->mParams[$param] as $moduleName ) {
 441                                 $instance = $this->mModuleMgr->getModule( $moduleName, $param );
 442                                 if ( $instance === null ) {
 443                                         ApiBase::dieDebug( __METHOD__, 'Error instantiating module' );
 444                                 }
 445                                 // Ignore duplicates. TODO 2.0: die()?
 446                                 if ( !array_key_exists( $moduleName, $modules ) ) {
 447                                         $modules[$moduleName] = $instance;
 448                                 }
 449                         }
 450                 }
 451         }
 452
 453         /**
 454          * Appends an element for each page in the current pageSet with the
 455          * most general information (id, title), plus any title normalizations
 456          * and missing or invalid title/pageids/revids.
 457          */
 458         private function outputGeneralPageInfo() {
 459                 $pageSet = $this->getPageSet();
 460                 $result = $this->getResult();
 461
 462                 // We don't check for a full result set here because we can't be adding
 463                 // more than 380K. The maximum revision size is in the megabyte range,
 464                 // and the maximum result size must be even higher than that.
 465
 466                 $values = $pageSet->getNormalizedTitlesAsResult( $result );
 467                 if ( $values ) {
 468                         $result->addValue( 'query', 'normalized', $values );
 469                 }
 470                 $values = $pageSet->getConvertedTitlesAsResult( $result );
 471                 if ( $values ) {
 472                         $result->addValue( 'query', 'converted', $values );
 473                 }
 474                 $values = $pageSet->getInterwikiTitlesAsResult( $result, $this->mParams['iwurl'] );
 475                 if ( $values ) {
 476                         $result->addValue( 'query', 'interwiki', $values );
 477                 }
 478                 $values = $pageSet->getRedirectTitlesAsResult( $result );
 479                 if ( $values ) {
 480                         $result->addValue( 'query', 'redirects', $values );
 481                 }
 482                 $values = $pageSet->getMissingRevisionIDsAsResult( $result );
 483                 if ( $values ) {
 484                         $result->addValue( 'query', 'badrevids', $values );
 485                 }
 486
 487                 // Page elements
 488                 $pages = array();
 489
 490                 // Report any missing titles
 491                 foreach ( $pageSet->getMissingTitles() as $fakeId => $title ) {
 492                         $vals = array();
 493                         ApiQueryBase::addTitleInfo( $vals, $title );
 494                         $vals['missing'] = '';
 495                         $pages[$fakeId] = $vals;
 496                 }
 497                 // Report any invalid titles
 498                 foreach ( $pageSet->getInvalidTitles() as $fakeId => $title ) {
 499                         $pages[$fakeId] = array( 'title' => $title, 'invalid' => '' );
 500                 }
 501                 // Report any missing page ids
 502                 foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
 503                         $pages[$pageid] = array(
 504                                 'pageid' => $pageid,
 505                                 'missing' => ''
 506                         );
 507                 }
 508                 // Report special pages
 509                 /** @var $title Title */
 510                 foreach ( $pageSet->getSpecialTitles() as $fakeId => $title ) {
 511                         $vals = array();
 512                         ApiQueryBase::addTitleInfo( $vals, $title );
 513                         $vals['special'] = '';
 514                         if ( $title->isSpecialPage() &&
 515                                         !SpecialPageFactory::exists( $title->getDBkey() ) ) {
 516                                 $vals['missing'] = '';
 517                         } elseif ( $title->getNamespace() == NS_MEDIA &&
 518                                         !wfFindFile( $title ) ) {
 519                                 $vals['missing'] = '';
 520                         }
 521                         $pages[$fakeId] = $vals;
 522                 }
 523
 524                 // Output general page information for found titles
 525                 foreach ( $pageSet->getGoodTitles() as $pageid => $title ) {
 526                         $vals = array();
 527                         $vals['pageid'] = $pageid;
 528                         ApiQueryBase::addTitleInfo( $vals, $title );
 529                         $pages[$pageid] = $vals;
 530                 }
 531
 532                 if ( count( $pages ) ) {
 533                         if ( $this->mParams['indexpageids'] ) {
 534                                 $pageIDs = array_keys( $pages );
 535                                 // json treats all map keys as strings - converting to match
 536                                 $pageIDs = array_map( 'strval', $pageIDs );
 537                                 $result->setIndexedTagName( $pageIDs, 'id' );
 538                                 $result->addValue( 'query', 'pageids', $pageIDs );
 539                         }
 540
 541                         $result->setIndexedTagName( $pages, 'page' );
 542                         $result->addValue( 'query', 'pages', $pages );
 543                 }
 544                 if ( $this->mParams['export'] ) {
 545                         $this->doExport( $pageSet, $result );
 546                 }
 547         }
 548
 549         /**
 550          * This method is called by the generator base when generator in the smart-continue
 551          * mode tries to set 'query-continue' value. ApiQuery stores those values separately
 552          * until the post-processing when it is known if the generation should continue or repeat.
 553          * @param ApiQueryGeneratorBase $module generator module
 554          * @param string $paramName
 555          * @param mixed $paramValue
 556          * @return bool true if processed, false if this is a legacy continue
 557          */
 558         public function setGeneratorContinue( $module, $paramName, $paramValue ) {
 559                 if ( $this->mUseLegacyContinue ) {
 560                         return false;
 561                 }
 562                 $paramName = $module->encodeParamName( $paramName );
 563                 if ( $this->mGeneratorContinue === null ) {
 564                         $this->mGeneratorContinue = array();
 565                 }
 566                 $this->mGeneratorContinue[$paramName] = $paramValue;
 567                 return true;
 568         }
 569
 570         /**
 571          * @param $pageSet ApiPageSet Pages to be exported
 572          * @param $result ApiResult Result to output to
 573          */
 574         private function doExport( $pageSet, $result ) {
 575                 $exportTitles = array();
 576                 $titles = $pageSet->getGoodTitles();
 577                 if ( count( $titles ) ) {
 578                         $user = $this->getUser();
 579                         /** @var $title Title */
 580                         foreach ( $titles as $title ) {
 581                                 if ( $title->userCan( 'read', $user ) ) {
 582                                         $exportTitles[] = $title;
 583                                 }
 584                         }
 585                 }
 586
 587                 $exporter = new WikiExporter( $this->getDB() );
 588                 // WikiExporter writes to stdout, so catch its
 589                 // output with an ob
 590                 ob_start();
 591                 $exporter->openStream();
 592                 foreach ( $exportTitles as $title ) {
 593                         $exporter->pageByTitle( $title );
 594                 }
 595                 $exporter->closeStream();
 596                 $exportxml = ob_get_contents();
 597                 ob_end_clean();
 598
 599                 // Don't check the size of exported stuff
 600                 // It's not continuable, so it would cause more
 601                 // problems than it'd solve
 602                 $result->disableSizeCheck();
 603                 if ( $this->mParams['exportnowrap'] ) {
 604                         $result->reset();
 605                         // Raw formatter will handle this
 606                         $result->addValue( null, 'text', $exportxml );
 607                         $result->addValue( null, 'mime', 'text/xml' );
 608                 } else {
 609                         $r = array();
 610                         ApiResult::setContent( $r, $exportxml );
 611                         $result->addValue( 'query', 'export', $r );
 612                 }
 613                 $result->enableSizeCheck();
 614         }
 615
 616         public function getAllowedParams( $flags = 0 ) {
 617                 $result = array(
 618                         'prop' => array(
 619                                 ApiBase::PARAM_ISMULTI => true,
 620                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'prop' )
 621                         ),
 622                         'list' => array(
 623                                 ApiBase::PARAM_ISMULTI => true,
 624                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'list' )
 625                         ),
 626                         'meta' => array(
 627                                 ApiBase::PARAM_ISMULTI => true,
 628                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'meta' )
 629                         ),
 630                         'indexpageids' => false,
 631                         'export' => false,
 632                         'exportnowrap' => false,
 633                         'iwurl' => false,
 634                         'continue' => null,
 635                 );
 636                 if ( $flags ) {
 637                         $result += $this->getPageSet()->getFinalParams( $flags );
 638                 }
 639                 return $result;
 640         }
 641
 642         /**
 643          * Override the parent to generate help messages for all available query modules.
 644          * @return string
 645          */
 646         public function makeHelpMsg() {
 647
 648                 // Use parent to make default message for the query module
 649                 $msg = parent::makeHelpMsg();
 650
 651                 $querySeparator = str_repeat( '--- ', 12 );
 652                 $moduleSeparator = str_repeat( '*** ', 14 );
 653                 $msg .= "\n$querySeparator Query: Prop  $querySeparator\n\n";
 654                 $msg .= $this->makeHelpMsgHelper( 'prop' );
 655                 $msg .= "\n$querySeparator Query: List  $querySeparator\n\n";
 656                 $msg .= $this->makeHelpMsgHelper( 'list' );
 657                 $msg .= "\n$querySeparator Query: Meta  $querySeparator\n\n";
 658                 $msg .= $this->makeHelpMsgHelper( 'meta' );
 659                 $msg .= "\n\n$moduleSeparator Modules: continuation  $moduleSeparator\n\n";
 660
 661                 return $msg;
 662         }
 663
 664         /**
 665          * For all modules of a given group, generate help messages and join them together
 666          * @param string $group Module group
 667          * @return string
 668          */
 669         private function makeHelpMsgHelper( $group ) {
 670                 $moduleDescriptions = array();
 671
 672                 $moduleNames = $this->mModuleMgr->getNames( $group );
 673                 sort( $moduleNames );
 674                 foreach ( $moduleNames as $name ) {
 675                         /**
 676                          * @var $module ApiQueryBase
 677                          */
 678                         $module = $this->mModuleMgr->getModule( $name );
 679
 680                         $msg = ApiMain::makeHelpMsgHeader( $module, $group );
 681                         $msg2 = $module->makeHelpMsg();
 682                         if ( $msg2 !== false ) {
 683                                 $msg .= $msg2;
 684                         }
 685                         if ( $module instanceof ApiQueryGeneratorBase ) {
 686                                 $msg .= "Generator:\n  This module may be used as a generator\n";
 687                         }
 688                         $moduleDescriptions[] = $msg;
 689                 }
 690
 691                 return implode( "\n", $moduleDescriptions );
 692         }
 693
 694         public function shouldCheckMaxlag() {
 695                 return true;
 696         }
 697
 698         public function getParamDescription() {
 699                 return $this->getPageSet()->getParamDescription() + array(
 700                         'prop' => 'Which properties to get for the titles/revisions/pageids. Module help is available below',
 701                         'list' => 'Which lists to get. Module help is available below',
 702                         'meta' => 'Which metadata to get about the site. Module help is available below',
 703                         'indexpageids' => 'Include an additional pageids section listing all returned page IDs',
 704                         'export' => 'Export the current revisions of all given or generated pages',
 705                         'exportnowrap' => 'Return the export XML without wrapping it in an XML result (same format as Special:Export). Can only be used with export',
 706                         'iwurl' => 'Whether to get the full URL if the title is an interwiki link',
 707                         'continue' => array(
 708                                 'When present, formats query-continue as key-value pairs that should simply be merged into the original request.',
 709                                 'This parameter must be set to an empty string in the initial query.',
 710                                 'This parameter is recommended for all new development, and will be made default in the next API version.' ),
 711                 );
 712         }
 713
 714         public function getDescription() {
 715                 return array(
 716                         'Query API module allows applications to get needed pieces of data from the MediaWiki databases,',
 717                         'and is loosely based on the old query.php interface.',
 718                         'All data modifications will first have to use query to acquire a token to prevent abuse from malicious sites'
 719                 );
 720         }
 721
 722         public function getPossibleErrors() {
 723                 return array_merge(
 724                         parent::getPossibleErrors(),
 725                         $this->getPageSet()->getPossibleErrors()
 726                 );
 727         }
 728
 729         public function getExamples() {
 730                 return array(
 731                         'api.php?action=query&prop=revisions&meta=siteinfo&titles=Main%20Page&rvprop=user|comment&continue=',
 732                         'api.php?action=query&generator=allpages&gapprefix=API/&prop=revisions&continue=',
 733                 );
 734         }
 735
 736         public function getHelpUrls() {
 737                 return array(
 738                         'https://www.mediawiki.org/wiki/API:Meta',
 739                         'https://www.mediawiki.org/wiki/API:Properties',
 740                         'https://www.mediawiki.org/wiki/API:Lists',
 741                 );
 742         }
 743 }