ApiQuery.php

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<?php
use MediaWiki\Export\WikiExporterFactory;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Title\Title;
use MediaWiki\Title\TitleFactory;
use MediaWiki\Title\TitleFormatter;
use Wikimedia\ObjectFactory\ObjectFactory;
use Wikimedia\ParamValidator\ParamValidator;
 
class ApiQuery extends ApiBase {
 
    private const QUERY_PROP_MODULES = [
        'categories' => [
            'class' => ApiQueryCategories::class,
        ],
        'categoryinfo' => [
            'class' => ApiQueryCategoryInfo::class,
        ],
        'contributors' => [
            'class' => ApiQueryContributors::class,
            'services' => [
                'RevisionStore',
                'ActorMigration',
                'UserGroupManager',
                'GroupPermissionsLookup',
                'TempUserConfig'
            ]
        ],
        'deletedrevisions' => [
            'class' => ApiQueryDeletedRevisions::class,
            'services' => [
                'RevisionStore',
                'ContentHandlerFactory',
                'ParserFactory',
                'SlotRoleRegistry',
                'ChangeTagDefStore',
                'LinkBatchFactory',
                'ContentRenderer',
                'ContentTransformer',
                'CommentFormatter',
                'TempUserCreator',
                'UserFactory',
            ]
        ],
        'duplicatefiles' => [
            'class' => ApiQueryDuplicateFiles::class,
            'services' => [
                'RepoGroup',
            ]
        ],
        'extlinks' => [
            'class' => ApiQueryExternalLinks::class,
            'services' => [
                'UrlUtils',
            ],
        ],
        'fileusage' => [
            'class' => ApiQueryBacklinksprop::class,
            'services' => [
                // Same as for linkshere, redirects, transcludedin
                'LinksMigration',
            ]
        ],
        'images' => [
            'class' => ApiQueryImages::class,
        ],
        'imageinfo' => [
            'class' => ApiQueryImageInfo::class,
            'services' => [
                // Same as for stashimageinfo
                'RepoGroup',
                'ContentLanguage',
                'BadFileLookup',
            ]
        ],
        'info' => [
            'class' => ApiQueryInfo::class,
            'services' => [
                'ContentLanguage',
                'LinkBatchFactory',
                'NamespaceInfo',
                'TitleFactory',
                'TitleFormatter',
                'WatchedItemStore',
                'LanguageConverterFactory',
                'RestrictionStore',
                'LinksMigration',
                'TempUserCreator',
                'UserFactory',
                'IntroMessageBuilder',
                'PreloadedContentBuilder',
                'RevisionLookup',
                'UrlUtils',
            ],
        ],
        'links' => [
            'class' => ApiQueryLinks::class,
            'services' => [
                // Same as for templates
                'LinkBatchFactory',
                'LinksMigration',
            ]
        ],
        'linkshere' => [
            'class' => ApiQueryBacklinksprop::class,
            'services' => [
                // Same as for fileusage, redirects, transcludedin
                'LinksMigration',
            ]
        ],
        'iwlinks' => [
            'class' => ApiQueryIWLinks::class,
            'services' => [
                'UrlUtils',
            ]
        ],
        'langlinks' => [
            'class' => ApiQueryLangLinks::class,
            'services' => [
                'LanguageNameUtils',
                'ContentLanguage',
                'UrlUtils',
            ]
        ],
        'pageprops' => [
            'class' => ApiQueryPageProps::class,
            'services' => [
                'PageProps',
            ]
        ],
        'redirects' => [
            'class' => ApiQueryBacklinksprop::class,
            'services' => [
                // Same as for fileusage, linkshere, transcludedin
                'LinksMigration',
            ]
        ],
        'revisions' => [
            'class' => ApiQueryRevisions::class,
            'services' => [
                'RevisionStore',
                'ContentHandlerFactory',
                'ParserFactory',
                'SlotRoleRegistry',
                'ChangeTagDefStore',
                'ActorMigration',
                'ContentRenderer',
                'ContentTransformer',
                'CommentFormatter',
                'TempUserCreator',
                'UserFactory',
                'TitleFormatter',
            ]
        ],
        'stashimageinfo' => [
            'class' => ApiQueryStashImageInfo::class,
            'services' => [
                // Same as for imageinfo
                'RepoGroup',
                'ContentLanguage',
                'BadFileLookup',
            ]
        ],
        'templates' => [
            'class' => ApiQueryLinks::class,
            'services' => [
                // Same as for links
                'LinkBatchFactory',
                'LinksMigration',
            ]
        ],
        'transcludedin' => [
            'class' => ApiQueryBacklinksprop::class,
            'services' => [
                // Same as for fileusage, linkshere, redirects
                'LinksMigration',
            ]
        ],
    ];
 
    private const QUERY_LIST_MODULES = [
        'allcategories' => [
            'class' => ApiQueryAllCategories::class,
        ],
        'alldeletedrevisions' => [
            'class' => ApiQueryAllDeletedRevisions::class,
            'services' => [
                'RevisionStore',
                'ContentHandlerFactory',
                'ParserFactory',
                'SlotRoleRegistry',
                'ChangeTagDefStore',
                'NamespaceInfo',
                'ContentRenderer',
                'ContentTransformer',
                'CommentFormatter',
                'TempUserCreator',
                'UserFactory',
            ]
        ],
        'allfileusages' => [
            'class' => ApiQueryAllLinks::class,
            'services' => [
                // Same as for alllinks, allredirects, alltransclusions
                'NamespaceInfo',
                'GenderCache',
                'LinksMigration',
            ]
        ],
        'allimages' => [
            'class' => ApiQueryAllImages::class,
            'services' => [
                'RepoGroup',
                'GroupPermissionsLookup',
            ]
        ],
        'alllinks' => [
            'class' => ApiQueryAllLinks::class,
            'services' => [
                // Same as for allfileusages, allredirects, alltransclusions
                'NamespaceInfo',
                'GenderCache',
                'LinksMigration',
            ]
        ],
        'allpages' => [
            'class' => ApiQueryAllPages::class,
            'services' => [
                'NamespaceInfo',
                'GenderCache',
                'RestrictionStore',
            ]
        ],
        'allredirects' => [
            'class' => ApiQueryAllLinks::class,
            'services' => [
                // Same as for allfileusages, alllinks, alltransclusions
                'NamespaceInfo',
                'GenderCache',
                'LinksMigration',
            ]
        ],
        'allrevisions' => [
            'class' => ApiQueryAllRevisions::class,
            'services' => [
                'RevisionStore',
                'ContentHandlerFactory',
                'ParserFactory',
                'SlotRoleRegistry',
                'ActorMigration',
                'NamespaceInfo',
                'ContentRenderer',
                'ContentTransformer',
                'CommentFormatter',
                'TempUserCreator',
                'UserFactory',
            ]
        ],
        'mystashedfiles' => [
            'class' => ApiQueryMyStashedFiles::class,
        ],
        'alltransclusions' => [
            'class' => ApiQueryAllLinks::class,
            'services' => [
                // Same as for allfileusages, alllinks, allredirects
                'NamespaceInfo',
                'GenderCache',
                'LinksMigration',
            ]
        ],
        'allusers' => [
            'class' => ApiQueryAllUsers::class,
            'services' => [
                'UserFactory',
                'UserGroupManager',
                'GroupPermissionsLookup',
                'ContentLanguage',
            ]
        ],
        'backlinks' => [
            'class' => ApiQueryBacklinks::class,
            'services' => [
                'LinksMigration',
            ]
        ],
        'blocks' => [
            'class' => ApiQueryBlocks::class,
            'services' => [
                'DatabaseBlockStore',
                'BlockActionInfo',
                'BlockRestrictionStore',
                'CommentStore',
                'HideUserUtils',
            ],
        ],
        'categorymembers' => [
            'class' => ApiQueryCategoryMembers::class,
            'services' => [
                'CollationFactory',
            ]
        ],
        'deletedrevs' => [
            'class' => ApiQueryDeletedrevs::class,
            'services' => [
                'CommentStore',
                'RowCommentFormatter',
                'RevisionStore',
                'ChangeTagDefStore',
                'LinkBatchFactory',
            ],
        ],
        'embeddedin' => [
            'class' => ApiQueryBacklinks::class,
            'services' => [
                'LinksMigration',
            ]
        ],
        'exturlusage' => [
            'class' => ApiQueryExtLinksUsage::class,
            'services' => [
                'UrlUtils',
            ],
        ],
        'filearchive' => [
            'class' => ApiQueryFilearchive::class,
            'services' => [
                'CommentStore',
                'CommentFormatter',
            ],
        ],
        'imageusage' => [
            'class' => ApiQueryBacklinks::class,
            'services' => [
                'LinksMigration',
            ]
        ],
        'iwbacklinks' => [
            'class' => ApiQueryIWBacklinks::class,
        ],
        'langbacklinks' => [
            'class' => ApiQueryLangBacklinks::class,
        ],
        'logevents' => [
            'class' => ApiQueryLogEvents::class,
            'services' => [
                'CommentStore',
                'RowCommentFormatter',
                'ChangeTagDefStore',
                'UserNameUtils',
            ],
        ],
        'pageswithprop' => [
            'class' => ApiQueryPagesWithProp::class,
        ],
        'pagepropnames' => [
            'class' => ApiQueryPagePropNames::class,
        ],
        'prefixsearch' => [
            'class' => ApiQueryPrefixSearch::class,
            'services' => [
                'SearchEngineConfig',
                'SearchEngineFactory',
            ],
        ],
        'protectedtitles' => [
            'class' => ApiQueryProtectedTitles::class,
            'services' => [
                'CommentStore',
                'RowCommentFormatter'
            ],
        ],
        'querypage' => [
            'class' => ApiQueryQueryPage::class,
            'services' => [
                'SpecialPageFactory',
            ]
        ],
        'random' => [
            'class' => ApiQueryRandom::class,
        ],
        'recentchanges' => [
            'class' => ApiQueryRecentChanges::class,
            'services' => [
                'CommentStore',
                'RowCommentFormatter',
                'ChangeTagDefStore',
                'SlotRoleStore',
                'SlotRoleRegistry',
                'UserNameUtils',
            ],
        ],
        'search' => [
            'class' => ApiQuerySearch::class,
            'services' => [
                'SearchEngineConfig',
                'SearchEngineFactory',
                'TitleMatcher',
            ],
        ],
        'tags' => [
            'class' => ApiQueryTags::class,
            'services' => [
                'ChangeTagsStore',
            ]
        ],
        'usercontribs' => [
            'class' => ApiQueryUserContribs::class,
            'services' => [
                'CommentStore',
                'UserIdentityLookup',
                'UserNameUtils',
                'RevisionStore',
                'ChangeTagDefStore',
                'ActorMigration',
                'CommentFormatter',
            ],
        ],
        'users' => [
            'class' => ApiQueryUsers::class,
            'services' => [
                'UserNameUtils',
                'UserFactory',
                'UserGroupManager',
                'GenderCache',
                'AuthManager',
            ],
        ],
        'watchlist' => [
            'class' => ApiQueryWatchlist::class,
            'services' => [
                'CommentStore',
                'WatchedItemQueryService',
                'ContentLanguage',
                'NamespaceInfo',
                'GenderCache',
                'CommentFormatter',
                'TempUserConfig'
            ],
        ],
        'watchlistraw' => [
            'class' => ApiQueryWatchlistRaw::class,
            'services' => [
                'WatchedItemQueryService',
                'ContentLanguage',
                'NamespaceInfo',
                'GenderCache',
            ]
        ],
    ];
 
    private const QUERY_META_MODULES = [
        'allmessages' => [
            'class' => ApiQueryAllMessages::class,
            'services' => [
                'ContentLanguage',
                'LanguageFactory',
                'LanguageNameUtils',
                'LocalisationCache',
                'MessageCache',
            ]
        ],
        'authmanagerinfo' => [
            'class' => ApiQueryAuthManagerInfo::class,
            'services' => [
                'AuthManager',
            ]
        ],
        'siteinfo' => [
            'class' => ApiQuerySiteinfo::class,
            'services' => [
                'UserOptionsLookup',
                'UserGroupManager',
                'LanguageConverterFactory',
                'LanguageFactory',
                'LanguageNameUtils',
                'ContentLanguage',
                'NamespaceInfo',
                'InterwikiLookup',
                'ParserFactory',
                'MagicWordFactory',
                'SpecialPageFactory',
                'SkinFactory',
                'DBLoadBalancer',
                'ReadOnlyMode',
                'UrlUtils',
                'TempUserConfig'
            ]
        ],
        'userinfo' => [
            'class' => ApiQueryUserInfo::class,
            'services' => [
                'TalkPageNotificationManager',
                'WatchedItemStore',
                'UserEditTracker',
                'UserOptionsLookup',
                'UserGroupManager',
            ]
        ],
        'filerepoinfo' => [
            'class' => ApiQueryFileRepoInfo::class,
            'services' => [
                'RepoGroup',
            ]
        ],
        'tokens' => [
            'class' => ApiQueryTokens::class,
        ],
        'languageinfo' => [
            'class' => ApiQueryLanguageinfo::class,
            'services' => [
                'LanguageFactory',
                'LanguageNameUtils',
                'LanguageFallback',
                'LanguageConverterFactory',
            ],
        ],
    ];
 
    private $mPageSet;
 
    private $mParams;
    private $mModuleMgr;
 
    private WikiExporterFactory $wikiExporterFactory;
    private TitleFormatter $titleFormatter;
    private TitleFactory $titleFactory;
 
    public function __construct(
        ApiMain $main,
        $action,
        ObjectFactory $objectFactory,
        WikiExporterFactory $wikiExporterFactory,
        TitleFormatter $titleFormatter,
        TitleFactory $titleFactory
    ) {
        parent::__construct( $main, $action );
 
        $this->mModuleMgr = new ApiModuleManager(
            $this,
            $objectFactory
        );
 
        // Allow custom modules to be added in LocalSettings.php
        $config = $this->getConfig();
        $this->mModuleMgr->addModules( self::QUERY_PROP_MODULES, 'prop' );
        $this->mModuleMgr->addModules( $config->get( MainConfigNames::APIPropModules ), 'prop' );
        $this->mModuleMgr->addModules( self::QUERY_LIST_MODULES, 'list' );
        $this->mModuleMgr->addModules( $config->get( MainConfigNames::APIListModules ), 'list' );
        $this->mModuleMgr->addModules( self::QUERY_META_MODULES, 'meta' );
        $this->mModuleMgr->addModules( $config->get( MainConfigNames::APIMetaModules ), 'meta' );
 
        $this->getHookRunner()->onApiQuery__moduleManager( $this->mModuleMgr );
 
        // Create PageSet that will process titles/pageids/revids/generator
        $this->mPageSet = new ApiPageSet( $this );
        $this->wikiExporterFactory = $wikiExporterFactory;
        $this->titleFormatter = $titleFormatter;
        $this->titleFactory = $titleFactory;
    }
 
    public function getModuleManager() {
        return $this->mModuleMgr;
    }
 
    public function getPageSet() {
        return $this->mPageSet;
    }
 
    public function getCustomPrinter() {
        // If &exportnowrap is set, use the raw formatter
        if ( $this->getParameter( 'export' ) &&
            $this->getParameter( 'exportnowrap' )
        ) {
            return new ApiFormatRaw( $this->getMain(),
                $this->getMain()->createPrinterByName( 'xml' ) );
        } else {
            return null;
        }
    }
 
    public function execute() {
        $this->mParams = $this->extractRequestParams();
 
        // Instantiate requested modules
        $allModules = [];
        $this->instantiateModules( $allModules, 'prop' );
        $propModules = array_keys( $allModules );
        $this->instantiateModules( $allModules, 'list' );
        $this->instantiateModules( $allModules, 'meta' );
 
        // Filter modules based on continue parameter
        $continuationManager = new ApiContinuationManager( $this, $allModules, $propModules );
        $this->setContinuationManager( $continuationManager );
        $modules = $continuationManager->getRunModules();
        '@phan-var ApiQueryBase[] $modules';
 
        $statsFactory = MediaWikiServices::getInstance()->getStatsFactory();
 
        if ( !$continuationManager->isGeneratorDone() ) {
            // Query modules may optimize data requests through the $this->getPageSet()
            // object by adding extra fields from the page table.
            foreach ( $modules as $module ) {
                // Augment api-query.$module.executeTiming metric with timings for requestExtraData()
                $timer = $statsFactory->getTiming( 'api_query_extraDataTiming_seconds' )
                    ->setLabel( 'module', $module->getModuleName() )
                    ->copyToStatsdAt( 'api-query.' . $module->getModuleName() . '.extraDataTiming' );
                $timer->start();
                $module->requestExtraData( $this->mPageSet );
                $timer->stop();
            }
            // Populate page/revision information
            $this->mPageSet->execute();
            // Record page information (title, namespace, if exists, etc)
            $this->outputGeneralPageInfo();
        } else {
            $this->mPageSet->executeDryRun();
        }
 
        $cacheMode = $this->mPageSet->getCacheMode();
 
        // Execute all unfinished modules
        foreach ( $modules as $module ) {
            // Break down of the api.query.executeTiming metric by query module.
            $timer = $statsFactory->getTiming( 'api_query_executeTiming_seconds' )
                ->setLabel( 'module', $module->getModuleName() )
                ->copyToStatsdAt( 'api-query.' . $module->getModuleName() . '.executeTiming' );
            $timer->start();
 
            $params = $module->extractRequestParams();
            $cacheMode = $this->mergeCacheMode(
                $cacheMode, $module->getCacheMode( $params ) );
            $module->execute();
 
            $timer->stop();
 
            $this->getHookRunner()->onAPIQueryAfterExecute( $module );
        }
 
        // Set the cache mode
        $this->getMain()->setCacheMode( $cacheMode );
 
        // Write the continuation data into the result
        $this->setContinuationManager( null );
        if ( $this->mParams['rawcontinue'] ) {
            $data = $continuationManager->getRawNonContinuation();
            if ( $data ) {
                $this->getResult()->addValue( null, 'query-noncontinue', $data,
                    ApiResult::ADD_ON_TOP | ApiResult::NO_SIZE_CHECK );
            }
            $data = $continuationManager->getRawContinuation();
            if ( $data ) {
                $this->getResult()->addValue( null, 'query-continue', $data,
                    ApiResult::ADD_ON_TOP | ApiResult::NO_SIZE_CHECK );
            }
        } else {
            $continuationManager->setContinuationIntoResult( $this->getResult() );
        }
    }
 
    protected function mergeCacheMode( $cacheMode, $modCacheMode ) {
        if ( $modCacheMode === 'anon-public-user-private' ) {
            if ( $cacheMode !== 'private' ) {
                $cacheMode = 'anon-public-user-private';
            }
        } elseif ( $modCacheMode === 'public' ) {
            // do nothing, if it's public already it will stay public
        } else {
            $cacheMode = 'private';
        }
 
        return $cacheMode;
    }
 
    private function instantiateModules( &$modules, $param ) {
        $wasPosted = $this->getRequest()->wasPosted();
        if ( isset( $this->mParams[$param] ) ) {
            foreach ( $this->mParams[$param] as $moduleName ) {
                $instance = $this->mModuleMgr->getModule( $moduleName, $param );
                if ( $instance === null ) {
                    ApiBase::dieDebug( __METHOD__, 'Error instantiating module' );
                }
                if ( !$wasPosted && $instance->mustBePosted() ) {
                    $this->dieWithErrorOrDebug( [ 'apierror-mustbeposted', $moduleName ] );
                }
                // Ignore duplicates. TODO 2.0: die()?
                if ( !array_key_exists( $moduleName, $modules ) ) {
                    $modules[$moduleName] = $instance;
                }
            }
        }
    }
 
    private function outputGeneralPageInfo() {
        $pageSet = $this->getPageSet();
        $result = $this->getResult();
 
        // We can't really handle max-result-size failure here, but we need to
        // check anyway in case someone set the limit stupidly low.
        $fit = true;
 
        $values = $pageSet->getNormalizedTitlesAsResult( $result );
        if ( $values ) {
            // @phan-suppress-next-line PhanRedundantCondition
            $fit = $fit && $result->addValue( 'query', 'normalized', $values );
        }
        $values = $pageSet->getConvertedTitlesAsResult( $result );
        if ( $values ) {
            $fit = $fit && $result->addValue( 'query', 'converted', $values );
        }
        $values = $pageSet->getInterwikiTitlesAsResult( $result, $this->mParams['iwurl'] );
        if ( $values ) {
            $fit = $fit && $result->addValue( 'query', 'interwiki', $values );
        }
        $values = $pageSet->getRedirectTitlesAsResult( $result );
        if ( $values ) {
            $fit = $fit && $result->addValue( 'query', 'redirects', $values );
        }
        $values = $pageSet->getMissingRevisionIDsAsResult( $result );
        if ( $values ) {
            $fit = $fit && $result->addValue( 'query', 'badrevids', $values );
        }
 
        // Page elements
        // Cannot use ApiPageSet::getInvalidTitlesAndRevisions, it does not set $fakeId
        $pages = [];
 
        // Report any missing titles
        foreach ( $pageSet->getMissingPages() as $fakeId => $page ) {
            $vals = [];
            $vals['ns'] = $page->getNamespace();
            $vals['title'] = $this->titleFormatter->getPrefixedText( $page );
            $vals['missing'] = true;
            $title = $this->titleFactory->newFromPageIdentity( $page );
            if ( $title->isKnown() ) {
                $vals['known'] = true;
            }
            $pages[$fakeId] = $vals;
        }
        // Report any invalid titles
        foreach ( $pageSet->getInvalidTitlesAndReasons() as $fakeId => $data ) {
            $pages[$fakeId] = $data + [ 'invalid' => true ];
        }
        // Report any missing page ids
        foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
            $pages[$pageid] = [
                'pageid' => $pageid,
                'missing' => true,
            ];
        }
        // Report special pages
        foreach ( $pageSet->getSpecialPages() as $fakeId => $page ) {
            $vals = [];
            $vals['ns'] = $page->getNamespace();
            $vals['title'] = $this->titleFormatter->getPrefixedText( $page );
            $vals['special'] = true;
            $title = $this->titleFactory->newFromPageReference( $page );
            if ( !$title->isKnown() ) {
                $vals['missing'] = true;
            }
            $pages[$fakeId] = $vals;
        }
 
        // Output general page information for found titles
        foreach ( $pageSet->getGoodPages() as $pageid => $page ) {
            $vals = [];
            $vals['pageid'] = $pageid;
            $vals['ns'] = $page->getNamespace();
            $vals['title'] = $this->titleFormatter->getPrefixedText( $page );
            $pages[$pageid] = $vals;
        }
 
        if ( count( $pages ) ) {
            $pageSet->populateGeneratorData( $pages );
            ApiResult::setArrayType( $pages, 'BCarray' );
 
            if ( $this->mParams['indexpageids'] ) {
                $pageIDs = array_keys( ApiResult::stripMetadataNonRecursive( $pages ) );
                // json treats all map keys as strings - converting to match
                $pageIDs = array_map( 'strval', $pageIDs );
                ApiResult::setIndexedTagName( $pageIDs, 'id' );
                $fit = $fit && $result->addValue( 'query', 'pageids', $pageIDs );
            }
 
            ApiResult::setIndexedTagName( $pages, 'page' );
            $fit = $fit && $result->addValue( 'query', 'pages', $pages );
        }
 
        if ( !$fit ) {
            $this->dieWithError( 'apierror-badconfig-resulttoosmall', 'badconfig' );
        }
 
        if ( $this->mParams['export'] ) {
            $this->doExport( $pageSet, $result );
        }
    }
 
    private function doExport( $pageSet, $result ) {
        $exportTitles = [];
        $titles = $pageSet->getGoodPages();
        if ( count( $titles ) ) {
            foreach ( $titles as $title ) {
                if ( $this->getAuthority()->authorizeRead( 'read', $title ) ) {
                    $exportTitles[] = $title;
                }
            }
        }
 
        $exporter = $this->wikiExporterFactory->getWikiExporter( $this->getDB() );
        $sink = new DumpStringOutput;
        $exporter->setOutputSink( $sink );
        $exporter->setSchemaVersion( $this->mParams['exportschema'] );
        $exporter->openStream();
        foreach ( $exportTitles as $title ) {
            $exporter->pageByTitle( $title );
        }
        $exporter->closeStream();
 
        // Don't check the size of exported stuff
        // It's not continuable, so it would cause more
        // problems than it'd solve
        if ( $this->mParams['exportnowrap'] ) {
            $result->reset();
            // Raw formatter will handle this
            $result->addValue( null, 'text', $sink, ApiResult::NO_SIZE_CHECK );
            $result->addValue( null, 'mime', 'text/xml', ApiResult::NO_SIZE_CHECK );
            $result->addValue( null, 'filename', 'export.xml', ApiResult::NO_SIZE_CHECK );
        } else {
            $result->addValue( 'query', 'export', $sink, ApiResult::NO_SIZE_CHECK );
            $result->addValue( 'query', ApiResult::META_BC_SUBELEMENTS, [ 'export' ] );
        }
    }
 
    public function getAllowedParams( $flags = 0 ) {
        $result = [
            'prop' => [
                ParamValidator::PARAM_ISMULTI => true,
                ParamValidator::PARAM_TYPE => 'submodule',
            ],
            'list' => [
                ParamValidator::PARAM_ISMULTI => true,
                ParamValidator::PARAM_TYPE => 'submodule',
            ],
            'meta' => [
                ParamValidator::PARAM_ISMULTI => true,
                ParamValidator::PARAM_TYPE => 'submodule',
            ],
            'indexpageids' => false,
            'export' => false,
            'exportnowrap' => false,
            'exportschema' => [
                ParamValidator::PARAM_DEFAULT => WikiExporter::schemaVersion(),
                ParamValidator::PARAM_TYPE => XmlDumpWriter::$supportedSchemas,
            ],
            'iwurl' => false,
            'continue' => [
                ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
            ],
            'rawcontinue' => false,
        ];
        if ( $flags ) {
            $result += $this->getPageSet()->getFinalParams( $flags );
        }
 
        return $result;
    }
 
    public function isReadMode() {
        // We need to make an exception for certain meta modules that should be
        // accessible even without the 'read' right. Restrict the exception as
        // much as possible: no other modules allowed, and no pageset
        // parameters either. We do allow the 'rawcontinue' and 'indexpageids'
        // parameters since frameworks might add these unconditionally and they
        // can't expose anything here.
        $allowedParams = [ 'rawcontinue' => 1, 'indexpageids' => 1 ];
        $this->mParams = $this->extractRequestParams();
        $request = $this->getRequest();
        foreach ( $this->mParams + $this->getPageSet()->extractRequestParams() as $param => $value ) {
            $needed = $param === 'meta';
            if ( !isset( $allowedParams[$param] ) && $request->getCheck( $param ) !== $needed ) {
                return true;
            }
        }
 
        // Ask each module if it requires read mode. Any true => this returns
        // true.
        $modules = [];
        $this->instantiateModules( $modules, 'meta' );
        foreach ( $modules as $module ) {
            if ( $module->isReadMode() ) {
                return true;
            }
        }
 
        return false;
    }
 
    public function isWriteMode() {
        // Ask each module if it requires write mode. If any require write mode this returns true.
        $modules = [];
        $this->mParams = $this->extractRequestParams();
        $this->instantiateModules( $modules, 'list' );
        $this->instantiateModules( $modules, 'meta' );
        $this->instantiateModules( $modules, 'prop' );
        foreach ( $modules as $module ) {
            if ( $module->isWriteMode() ) {
                return true;
            }
        }
 
        return false;
    }
 
    protected function getExamplesMessages() {
        $title = Title::newMainPage()->getPrefixedText();
        $mp = rawurlencode( $title );
 
        return [
            'action=query&prop=revisions&meta=siteinfo&' .
                "titles={$mp}&rvprop=user|comment&continue="
                => 'apihelp-query-example-revisions',
            'action=query&generator=allpages&gapprefix=API/&prop=revisions&continue='
                => 'apihelp-query-example-allpages',
        ];
    }
 
    public function getHelpUrls() {
        return [
            'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Query',
            'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Meta',
            'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Properties',
            'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Lists',
        ];
    }
}