Merge "ResourceLoader: Deprecate ResourceLoader::makeConfigSetScript"

[mediawiki.git] / includes / import / WikiImporter.php

<?php
/**
 * MediaWiki page data importer.
 *
 * Copyright © 2003,2005 Brooke Vibber <bvibber@wikimedia.org>
 * https://www.mediawiki.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup SpecialPage
 */

use MediaWiki\Cache\CacheKeyHelper;
use MediaWiki\Config\Config;
use MediaWiki\Content\Content;
use MediaWiki\Content\IContentHandlerFactory;
use MediaWiki\Deferred\DeferredUpdates;
use MediaWiki\Deferred\SiteStatsUpdate;
use MediaWiki\HookContainer\HookContainer;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\Language\Language;
use MediaWiki\MainConfigNames;
use MediaWiki\Page\PageIdentity;
use MediaWiki\Page\WikiPageFactory;
use MediaWiki\Permissions\Authority;
use MediaWiki\Revision\SlotRecord;
use MediaWiki\Revision\SlotRoleRegistry;
use MediaWiki\Status\Status;
use MediaWiki\Title\ForeignTitle;
use MediaWiki\Title\ImportTitleFactory;
use MediaWiki\Title\NaiveForeignTitleFactory;
use MediaWiki\Title\NaiveImportTitleFactory;
use MediaWiki\Title\NamespaceAwareForeignTitleFactory;
use MediaWiki\Title\NamespaceImportTitleFactory;
use MediaWiki\Title\NamespaceInfo;
use MediaWiki\Title\SubpageImportTitleFactory;
use MediaWiki\Title\Title;
use MediaWiki\Title\TitleFactory;
use MediaWiki\User\ExternalUserNames;
use Wikimedia\AtEase\AtEase;
use Wikimedia\Message\MessageParam;
use Wikimedia\Message\MessageSpecifier;
use Wikimedia\NormalizedException\NormalizedException;
use Wikimedia\Rdbms\IDBAccessObject;

/**
 * XML file reader for the page data importer.
 *
 * implements Special:Import
 * @ingroup SpecialPage
 */
class WikiImporter {
        /** @var XMLReader|null */
        private $reader;

        /** @var string */
        private $sourceAdapterId;

        /** @var array|null */
        private $foreignNamespaces = null;

        /** @var callable|null */
        private $mLogItemCallback;

        /** @var callable */
        private $mUploadCallback;

        /** @var callable|null */
        private $mRevisionCallback;

        /** @var callable|null */
        private $mPageCallback;

        /** @var callable|null */
        private $mSiteInfoCallback;

        /** @var callable|null */
        private $mPageOutCallback;

        /** @var callable|null */
        private $mNoticeCallback;

        /** @var bool|null */
        private $mDebug;

        /** @var bool|null */
        private $mImportUploads;

        /** @var string|null */
        private $mImageBasePath;

        /** @var bool */
        private $mNoUpdates = false;

        /** @var int */
        private $pageOffset = 0;

        private ImportTitleFactory $importTitleFactory;
        private ExternalUserNames $externalUserNames;

        /** @var array */
        private $countableCache = [];

        /** @var bool */
        private $disableStatisticsUpdate = false;

        /**
         * Authority used for permission checks only (to ensure that the user performing the import is
         * allowed to edit the pages they're importing). To skip the checks, use UltimateAuthority.
         *
         * If you want to also log the import actions, see ImportReporter.
         */
        private Authority $performer;

        private Config $config;
        private HookRunner $hookRunner;
        private Language $contentLanguage;
        private NamespaceInfo $namespaceInfo;
        private TitleFactory $titleFactory;
        private WikiPageFactory $wikiPageFactory;
        private UploadRevisionImporter $uploadRevisionImporter;
        private IContentHandlerFactory $contentHandlerFactory;
        private SlotRoleRegistry $slotRoleRegistry;

        /**
         * Creates an ImportXMLReader drawing from the source provided
         */
        public function __construct(
                ImportSource $source,
                Authority $performer,
                Config $config,
                HookContainer $hookContainer,
                Language $contentLanguage,
                NamespaceInfo $namespaceInfo,
                TitleFactory $titleFactory,
                WikiPageFactory $wikiPageFactory,
                UploadRevisionImporter $uploadRevisionImporter,
                IContentHandlerFactory $contentHandlerFactory,
                SlotRoleRegistry $slotRoleRegistry
        ) {
                $this->performer = $performer;
                $this->config = $config;
                $this->hookRunner = new HookRunner( $hookContainer );
                $this->contentLanguage = $contentLanguage;
                $this->namespaceInfo = $namespaceInfo;
                $this->titleFactory = $titleFactory;
                $this->wikiPageFactory = $wikiPageFactory;
                $this->uploadRevisionImporter = $uploadRevisionImporter;
                $this->contentHandlerFactory = $contentHandlerFactory;
                $this->slotRoleRegistry = $slotRoleRegistry;

                if ( !in_array( 'uploadsource', stream_get_wrappers() ) ) {
                        stream_wrapper_register( 'uploadsource', UploadSourceAdapter::class );
                }
                $this->sourceAdapterId = UploadSourceAdapter::registerSource( $source );

                $this->openReader();

                // Default callbacks
                $this->setPageCallback( [ $this, 'beforeImportPage' ] );
                $this->setRevisionCallback( [ $this, "importRevision" ] );
                $this->setUploadCallback( [ $this, 'importUpload' ] );
                $this->setLogItemCallback( [ $this, 'importLogItem' ] );
                $this->setPageOutCallback( [ $this, 'finishImportPage' ] );

                $this->importTitleFactory = new NaiveImportTitleFactory(
                        $this->contentLanguage,
                        $this->namespaceInfo,
                        $this->titleFactory
                );
                $this->externalUserNames = new ExternalUserNames( 'imported', false );
        }

        /**
         * @return null|XMLReader
         */
        public function getReader() {
                return $this->reader;
        }

        /**
         * @param string $err
         */
        public function throwXmlError( $err ) {
                $this->debug( "FAILURE: $err" );
                wfDebug( "WikiImporter XML error: $err" );
        }

        /**
         * @param string $data
         */
        public function debug( $data ) {
                if ( $this->mDebug ) {
                        wfDebug( "IMPORT: $data" );
                }
        }

        /**
         * @param string $data
         */
        public function warn( $data ) {
                wfDebug( "IMPORT: $data" );
        }

        /**
         * @param string $msg
         * @phpcs:ignore Generic.Files.LineLength
         * @param MessageParam|MessageSpecifier|string|int|float|list<MessageParam|MessageSpecifier|string|int|float> ...$params
         *   See Message::params()
         */
        public function notice( $msg, ...$params ) {
                if ( is_callable( $this->mNoticeCallback ) ) {
                        call_user_func( $this->mNoticeCallback, $msg, $params );
                } else { # No ImportReporter -> CLI
                        // T177997: the command line importers should call setNoticeCallback()
                        // for their own custom callback to echo the notice
                        wfDebug( wfMessage( $msg, $params )->text() );
                }
        }

        /**
         * Set debug mode...
         * @param bool $debug
         */
        public function setDebug( $debug ) {
                $this->mDebug = $debug;
        }

        /**
         * Set 'no updates' mode. In this mode, the link tables will not be updated by the importer
         * @param bool $noupdates
         */
        public function setNoUpdates( $noupdates ) {
                $this->mNoUpdates = $noupdates;
        }

        /**
         * Sets 'pageOffset' value. So it will skip the first n-1 pages
         * and start from the nth page. It's 1-based indexing.
         * @param int $nthPage
         * @since 1.29
         */
        public function setPageOffset( $nthPage ) {
                $this->pageOffset = $nthPage;
        }

        /**
         * Set a callback that displays notice messages
         *
         * @param callable $callback
         * @return callable
         */
        public function setNoticeCallback( $callback ) {
                return wfSetVar( $this->mNoticeCallback, $callback );
        }

        /**
         * Sets the action to perform as each new page in the stream is reached.
         * @param callable|null $callback
         * @return callable|null
         */
        public function setPageCallback( $callback ) {
                $previous = $this->mPageCallback;
                $this->mPageCallback = $callback;
                return $previous;
        }

        /**
         * Sets the action to perform as each page in the stream is completed.
         * Callback accepts the page title (as a Title object), a second object
         * with the original title form (in case it's been overridden into a
         * local namespace), and a count of revisions.
         *
         * @param callable|null $callback
         * @return callable|null
         */
        public function setPageOutCallback( $callback ) {
                $previous = $this->mPageOutCallback;
                $this->mPageOutCallback = $callback;
                return $previous;
        }

        /**
         * Sets the action to perform as each page revision is reached.
         * @param callable|null $callback
         * @return callable|null
         */
        public function setRevisionCallback( $callback ) {
                $previous = $this->mRevisionCallback;
                $this->mRevisionCallback = $callback;
                return $previous;
        }

        /**
         * Sets the action to perform as each file upload version is reached.
         * @param callable $callback
         * @return callable
         */
        public function setUploadCallback( $callback ) {
                $previous = $this->mUploadCallback;
                $this->mUploadCallback = $callback;
                return $previous;
        }

        /**
         * Sets the action to perform as each log item reached.
         * @param callable $callback
         * @return callable
         */
        public function setLogItemCallback( $callback ) {
                $previous = $this->mLogItemCallback;
                $this->mLogItemCallback = $callback;
                return $previous;
        }

        /**
         * Sets the action to perform when site info is encountered
         * @param callable $callback
         * @return callable
         */
        public function setSiteInfoCallback( $callback ) {
                $previous = $this->mSiteInfoCallback;
                $this->mSiteInfoCallback = $callback;
                return $previous;
        }

        /**
         * Sets the factory object to use to convert ForeignTitle objects into local
         * Title objects
         * @param ImportTitleFactory $factory
         */
        public function setImportTitleFactory( $factory ) {
                $this->importTitleFactory = $factory;
        }

        /**
         * Set a target namespace to override the defaults
         * @param null|int $namespace
         * @return bool
         */
        public function setTargetNamespace( $namespace ) {
                if ( $namespace === null ) {
                        // Don't override namespaces
                        $this->setImportTitleFactory(
                                new NaiveImportTitleFactory(
                                        $this->contentLanguage,
                                        $this->namespaceInfo,
                                        $this->titleFactory
                                )
                        );
                        return true;
                } elseif (
                        $namespace >= 0 &&
                        $this->namespaceInfo->exists( intval( $namespace ) )
                ) {
                        $namespace = intval( $namespace );
                        $this->setImportTitleFactory(
                                new NamespaceImportTitleFactory(
                                        $this->namespaceInfo,
                                        $this->titleFactory,
                                        $namespace
                                )
                        );
                        return true;
                } else {
                        return false;
                }
        }

        /**
         * Set a target root page under which all pages are imported
         * @param null|string $rootpage
         * @return Status
         */
        public function setTargetRootPage( $rootpage ) {
                $status = Status::newGood();
                $nsInfo = $this->namespaceInfo;
                if ( $rootpage === null ) {
                        // No rootpage
                        $this->setImportTitleFactory(
                                new NaiveImportTitleFactory(
                                        $this->contentLanguage,
                                        $nsInfo,
                                        $this->titleFactory
                                )
                        );
                } elseif ( $rootpage !== '' ) {
                        $rootpage = rtrim( $rootpage, '/' ); // avoid double slashes
                        $title = Title::newFromText( $rootpage );

                        if ( !$title || $title->isExternal() ) {
                                $status->fatal( 'import-rootpage-invalid' );
                        } elseif ( !$nsInfo->hasSubpages( $title->getNamespace() ) ) {
                                $displayNSText = $title->getNamespace() === NS_MAIN
                                        ? wfMessage( 'blanknamespace' )->text()
                                        : $this->contentLanguage->getNsText( $title->getNamespace() );
                                $status->fatal( 'import-rootpage-nosubpage', $displayNSText );
                        } else {
                                // set namespace to 'all', so the namespace check in processTitle() can pass
                                $this->setTargetNamespace( null );
                                $this->setImportTitleFactory(
                                        new SubpageImportTitleFactory(
                                                $nsInfo,
                                                $this->titleFactory,
                                                $title
                                        )
                                );
                        }
                }
                return $status;
        }

        /**
         * @param string $dir
         */
        public function setImageBasePath( $dir ) {
                $this->mImageBasePath = $dir;
        }

        /**
         * @param bool $import
         */
        public function setImportUploads( $import ) {
                $this->mImportUploads = $import;
        }

        /**
         * @since 1.31
         * @param string $usernamePrefix Prefix to apply to unknown (and possibly also known) usernames
         * @param bool $assignKnownUsers Whether to apply the prefix to usernames that exist locally
         */
        public function setUsernamePrefix( $usernamePrefix, $assignKnownUsers ) {
                $this->externalUserNames = new ExternalUserNames( $usernamePrefix, $assignKnownUsers );
        }

        /**
         * Statistics update can cause a lot of time
         * @since 1.29
         */
        public function disableStatisticsUpdate() {
                $this->disableStatisticsUpdate = true;
        }

        /**
         * Default per-page callback. Sets up some things related to site statistics
         * @param array $titleAndForeignTitle Two-element array, with Title object at
         * index 0 and ForeignTitle object at index 1
         * @return bool
         */
        public function beforeImportPage( $titleAndForeignTitle ) {
                $title = $titleAndForeignTitle[0];
                $page = $this->wikiPageFactory->newFromTitle( $title );
                $this->countableCache['title_' . $title->getPrefixedText()] = $page->isCountable();
                return true;
        }

        /**
         * Default per-revision callback, performs the import.
         * @param WikiRevision $revision
         * @return bool
         */
        public function importRevision( $revision ) {
                if ( !$revision->getContentHandler()->canBeUsedOn( $revision->getTitle() ) ) {
                        $this->notice( 'import-error-bad-location',
                                $revision->getTitle()->getPrefixedText(),
                                $revision->getID(),
                                $revision->getModel(),
                                $revision->getFormat()
                        );

                        return false;
                }

                try {
                        return $revision->importOldRevision();
                } catch ( MWContentSerializationException $ex ) {
                        $this->notice( 'import-error-unserialize',
                                $revision->getTitle()->getPrefixedText(),
                                $revision->getID(),
                                $revision->getModel(),
                                $revision->getFormat()
                        );
                }

                return false;
        }

        /**
         * Default per-revision callback, performs the import.
         * @param WikiRevision $revision
         * @return bool
         */
        public function importLogItem( $revision ) {
                return $revision->importLogItem();
        }

        /**
         * Dummy for now...
         * @param WikiRevision $revision
         * @return bool
         */
        public function importUpload( $revision ) {
                $status = $this->uploadRevisionImporter->import( $revision );
                return $status->isGood();
        }

        /**
         * Mostly for hook use
         * @param PageIdentity $pageIdentity
         * @param ForeignTitle $foreignTitle
         * @param int $revCount
         * @param int $sRevCount
         * @param array $pageInfo
         * @return bool
         */
        public function finishImportPage( PageIdentity $pageIdentity, $foreignTitle, $revCount,
                $sRevCount, $pageInfo
        ) {
                // Update article count statistics (T42009)
                // The normal counting logic in WikiPage->doEditUpdates() is designed for
                // one-revision-at-a-time editing, not bulk imports. In this situation it
                // suffers from issues of replica DB lag. We let WikiPage handle the total page
                // and revision count, and we implement our own custom logic for the
                // article (content page) count.
                if ( !$this->disableStatisticsUpdate ) {
                        $page = $this->wikiPageFactory->newFromTitle( $pageIdentity );

                        $page->loadPageData( IDBAccessObject::READ_LATEST );
                        $rev = $page->getRevisionRecord();
                        if ( $rev === null ) {

                                wfDebug( __METHOD__ . ': Skipping article count adjustment for ' . $pageIdentity .
                                        ' because WikiPage::getRevisionRecord() returned null' );
                        } else {
                                $update = $page->newPageUpdater( $this->performer )->prepareUpdate();
                                $countKey = 'title_' . CacheKeyHelper::getKeyForPage( $pageIdentity );
                                $countable = $update->isCountable();
                                if ( array_key_exists( $countKey, $this->countableCache ) &&
                                        $countable != $this->countableCache[$countKey] ) {
                                        DeferredUpdates::addUpdate( SiteStatsUpdate::factory( [
                                                'articles' => ( (int)$countable - (int)$this->countableCache[$countKey] )
                                        ] ) );
                                }
                        }
                }

                $title = Title::newFromPageIdentity( $pageIdentity );
                return $this->hookRunner->onAfterImportPage( $title, $foreignTitle,
                        $revCount, $sRevCount, $pageInfo );
        }

        /**
         * Notify the callback function of site info
         * @param array $siteInfo
         * @return mixed|false
         */
        private function siteInfoCallback( $siteInfo ) {
                if ( $this->mSiteInfoCallback ) {
                        return call_user_func_array(
                                $this->mSiteInfoCallback,
                                [ $siteInfo, $this ]
                        );
                } else {
                        return false;
                }
        }

        /**
         * Notify the callback function when a new "<page>" is reached.
         * @param array $title
         */
        public function pageCallback( $title ) {
                if ( $this->mPageCallback ) {
                        call_user_func( $this->mPageCallback, $title );
                }
        }

        /**
         * Notify the callback function when a "</page>" is closed.
         * @param PageIdentity $pageIdentity
         * @param ForeignTitle $foreignTitle
         * @param int $revCount
         * @param int $sucCount Number of revisions for which callback returned true
         * @param array $pageInfo Associative array of page information
         */
        private function pageOutCallback( PageIdentity $pageIdentity, $foreignTitle, $revCount,
                        $sucCount, $pageInfo ) {
                if ( $this->mPageOutCallback ) {
                        call_user_func_array( $this->mPageOutCallback, func_get_args() );
                }
        }

        /**
         * Notify the callback function of a revision
         * @param WikiRevision $revision
         * @return bool|mixed
         */
        private function revisionCallback( $revision ) {
                if ( $this->mRevisionCallback ) {
                        return call_user_func_array(
                                $this->mRevisionCallback,
                                [ $revision, $this ]
                        );
                } else {
                        return false;
                }
        }

        /**
         * Notify the callback function of a new log item
         * @param WikiRevision $revision
         * @return mixed|false
         */
        private function logItemCallback( $revision ) {
                if ( $this->mLogItemCallback ) {
                        return call_user_func_array(
                                $this->mLogItemCallback,
                                [ $revision, $this ]
                        );
                } else {
                        return false;
                }
        }

        /**
         * Retrieves the contents of the named attribute of the current element.
         * @param string $attr The name of the attribute
         * @return string The value of the attribute or an empty string if it is not set in the current
         * element.
         */
        public function nodeAttribute( $attr ) {
                return $this->reader->getAttribute( $attr ) ?? '';
        }

        /**
         * Shouldn't something like this be built-in to XMLReader?
         * Fetches text contents of the current element, assuming
         * no sub-elements or such scary things.
         * @return string
         * @internal
         */
        public function nodeContents() {
                if ( $this->reader->isEmptyElement ) {
                        return "";
                }
                $buffer = "";
                while ( $this->reader->read() ) {
                        switch ( $this->reader->nodeType ) {
                                case XMLReader::TEXT:
                                case XMLReader::CDATA:
                                case XMLReader::SIGNIFICANT_WHITESPACE:
                                        $buffer .= $this->reader->value;
                                        break;
                                case XMLReader::END_ELEMENT:
                                        return $buffer;
                        }
                }

                $this->reader->close();
                return '';
        }

        /**
         * Primary entry point
         * @throws Exception
         * @return bool
         */
        public function doImport() {
                $this->syntaxCheckXML();

                // Calls to reader->read need to be wrapped in calls to
                // libxml_disable_entity_loader() to avoid local file
                // inclusion attacks (T48932).
                // phpcs:ignore Generic.PHP.NoSilencedErrors -- suppress deprecation per T268847
                $oldDisable = @libxml_disable_entity_loader( true );
                try {
                        $this->reader->read();

                        if ( $this->reader->localName != 'mediawiki' ) {
                                // phpcs:ignore Generic.PHP.NoSilencedErrors
                                @libxml_disable_entity_loader( $oldDisable );
                                $error = libxml_get_last_error();
                                if ( $error ) {
                                        throw new NormalizedException( "XML error at line {line}: {message}", [
                                                'line' => $error->line,
                                                'message' => $error->message,
                                        ] );
                                } else {
                                        throw new UnexpectedValueException(
                                                "Expected '<mediawiki>' tag, got '<{$this->reader->localName}>' tag."
                                        );
                                }
                        }
                        $this->debug( "<mediawiki> tag is correct." );

                        $this->debug( "Starting primary dump processing loop." );

                        $keepReading = $this->reader->read();
                        $skip = false;
                        $pageCount = 0;
                        while ( $keepReading ) {
                                $tag = $this->reader->localName;
                                if ( $this->pageOffset ) {
                                        if ( $tag === 'page' ) {
                                                $pageCount++;
                                        }
                                        if ( $pageCount < $this->pageOffset ) {
                                                $keepReading = $this->reader->next();
                                                continue;
                                        }
                                }
                                $type = $this->reader->nodeType;

                                if ( !$this->hookRunner->onImportHandleToplevelXMLTag( $this ) ) {
                                        // Do nothing
                                } elseif ( $tag == 'mediawiki' && $type == XMLReader::END_ELEMENT ) {
                                        break;
                                } elseif ( $tag == 'siteinfo' ) {
                                        $this->handleSiteInfo();
                                } elseif ( $tag == 'page' ) {
                                        $this->handlePage();
                                } elseif ( $tag == 'logitem' ) {
                                        $this->handleLogItem();
                                } elseif ( $tag != '#text' ) {
                                        $this->warn( "Unhandled top-level XML tag $tag" );

                                        $skip = true;
                                }

                                if ( $skip ) {
                                        $keepReading = $this->reader->next();
                                        $skip = false;
                                        $this->debug( "Skip" );
                                } else {
                                        $keepReading = $this->reader->read();
                                }
                        }
                } finally {
                        // phpcs:ignore Generic.PHP.NoSilencedErrors
                        @libxml_disable_entity_loader( $oldDisable );
                        $this->reader->close();
                }

                return true;
        }

        private function handleSiteInfo() {
                $this->debug( "Enter site info handler." );
                $siteInfo = [];

                // Fields that can just be stuffed in the siteInfo object
                $normalFields = [ 'sitename', 'base', 'generator', 'case' ];

                while ( $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                        $this->reader->localName == 'siteinfo' ) {
                                break;
                        }

                        $tag = $this->reader->localName;

                        if ( $tag == 'namespace' ) {
                                $this->foreignNamespaces[$this->nodeAttribute( 'key' )] =
                                        $this->nodeContents();
                        } elseif ( in_array( $tag, $normalFields ) ) {
                                $siteInfo[$tag] = $this->nodeContents();
                        }
                }

                $siteInfo['_namespaces'] = $this->foreignNamespaces;
                $this->siteInfoCallback( $siteInfo );
        }

        private function handleLogItem() {
                $this->debug( "Enter log item handler." );
                $logInfo = [];

                // Fields that can just be stuffed in the pageInfo object
                $normalFields = [ 'id', 'comment', 'type', 'action', 'timestamp',
                        'logtitle', 'params' ];

                while ( $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                        $this->reader->localName == 'logitem' ) {
                                break;
                        }

                        $tag = $this->reader->localName;

                        if ( !$this->hookRunner->onImportHandleLogItemXMLTag( $this, $logInfo ) ) {
                                // Do nothing
                        } elseif ( in_array( $tag, $normalFields ) ) {
                                $logInfo[$tag] = $this->nodeContents();
                        } elseif ( $tag == 'contributor' ) {
                                $logInfo['contributor'] = $this->handleContributor();
                        } elseif ( $tag != '#text' ) {
                                $this->warn( "Unhandled log-item XML tag $tag" );
                        }
                }

                $this->processLogItem( $logInfo );
        }

        /**
         * @param array $logInfo
         * @return mixed|false
         */
        private function processLogItem( $logInfo ) {
                $revision = new WikiRevision();

                if ( isset( $logInfo['id'] ) ) {
                        $revision->setID( $logInfo['id'] );
                }
                $revision->setType( $logInfo['type'] );
                $revision->setAction( $logInfo['action'] );
                if ( isset( $logInfo['timestamp'] ) ) {
                        $revision->setTimestamp( $logInfo['timestamp'] );
                }
                if ( isset( $logInfo['params'] ) ) {
                        $revision->setParams( $logInfo['params'] );
                }
                if ( isset( $logInfo['logtitle'] ) ) {
                        // @todo Using Title for non-local titles is a recipe for disaster.
                        // We should use ForeignTitle here instead.
                        $revision->setTitle( Title::newFromText( $logInfo['logtitle'] ) );
                }

                $revision->setNoUpdates( $this->mNoUpdates );

                if ( isset( $logInfo['comment'] ) ) {
                        $revision->setComment( $logInfo['comment'] );
                }

                if ( isset( $logInfo['contributor']['username'] ) ) {
                        $revision->setUsername(
                                $this->externalUserNames->applyPrefix( $logInfo['contributor']['username'] )
                        );
                } elseif ( isset( $logInfo['contributor']['ip'] ) ) {
                        $revision->setUserIP( $logInfo['contributor']['ip'] );
                } else {
                        $revision->setUsername( $this->externalUserNames->addPrefix( 'Unknown user' ) );
                }

                return $this->logItemCallback( $revision );
        }

        private function handlePage() {
                // Handle page data.
                $this->debug( "Enter page handler." );
                $pageInfo = [ 'revisionCount' => 0, 'successfulRevisionCount' => 0 ];

                // Fields that can just be stuffed in the pageInfo object
                $normalFields = [ 'title', 'ns', 'id', 'redirect', 'restrictions' ];

                $skip = false;
                $badTitle = false;

                while ( $skip ? $this->reader->next() : $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                        $this->reader->localName == 'page' ) {
                                break;
                        }

                        $skip = false;

                        $tag = $this->reader->localName;

                        if ( $badTitle ) {
                                // The title is invalid, bail out of this page
                                $skip = true;
                        } elseif ( !$this->hookRunner->onImportHandlePageXMLTag( $this, $pageInfo ) ) {
                                // Do nothing
                        } elseif ( in_array( $tag, $normalFields ) ) {
                                // An XML snippet:
                                // <page>
                                //     <id>123</id>
                                //     <title>Page</title>
                                //     <redirect title="NewTitle"/>
                                //     ...
                                // Because the redirect tag is built differently, we need special handling for that case.
                                if ( $tag == 'redirect' ) {
                                        $pageInfo[$tag] = $this->nodeAttribute( 'title' );
                                } else {
                                        $pageInfo[$tag] = $this->nodeContents();
                                }
                        } elseif ( $tag == 'revision' || $tag == 'upload' ) {
                                if ( !isset( $title ) ) {
                                        $title = $this->processTitle( $pageInfo['title'],
                                                $pageInfo['ns'] ?? null );

                                        // $title is either an array of two titles or false.
                                        if ( is_array( $title ) ) {
                                                $this->pageCallback( $title );
                                                [ $pageInfo['_title'], $foreignTitle ] = $title;
                                        } else {
                                                $badTitle = true;
                                                $skip = true;
                                        }
                                }

                                if ( $title ) {
                                        if ( $tag == 'revision' ) {
                                                $this->handleRevision( $pageInfo );
                                        } else {
                                                $this->handleUpload( $pageInfo );
                                        }
                                }
                        } elseif ( $tag != '#text' ) {
                                $this->warn( "Unhandled page XML tag $tag" );
                                $skip = true;
                        }
                }

                // @note $pageInfo is only set if a valid $title is processed above with
                //       no error. If we have a valid $title, then pageCallback is called
                //       above, $pageInfo['title'] is set and we do pageOutCallback here.
                //       If $pageInfo['_title'] is not set, then $foreignTitle is also not
                //       set since they both come from $title above.
                if ( array_key_exists( '_title', $pageInfo ) ) {
                        /** @var Title $title */
                        $title = $pageInfo['_title'];
                        $this->pageOutCallback(
                                $title,
                                // @phan-suppress-next-line PhanPossiblyUndeclaredVariable Set together with _title key
                                $foreignTitle,
                                $pageInfo['revisionCount'],
                                $pageInfo['successfulRevisionCount'],
                                $pageInfo
                        );
                }
        }

        /**
         * @param array &$pageInfo
         */
        private function handleRevision( &$pageInfo ) {
                $this->debug( "Enter revision handler" );
                $revisionInfo = [];

                $normalFields = [ 'id', 'parentid', 'timestamp', 'comment', 'minor', 'origin',
                        'model', 'format', 'text', 'sha1' ];

                $skip = false;

                while ( $skip ? $this->reader->next() : $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                        $this->reader->localName == 'revision' ) {
                                break;
                        }

                        $tag = $this->reader->localName;

                        if ( !$this->hookRunner->onImportHandleRevisionXMLTag(
                                $this, $pageInfo, $revisionInfo )
                        ) {
                                // Do nothing
                        } elseif ( in_array( $tag, $normalFields ) ) {
                                $revisionInfo[$tag] = $this->nodeContents();
                        } elseif ( $tag == 'content' ) {
                                // We can have multiple content tags, so make this an array.
                                $revisionInfo[$tag][] = $this->handleContent();
                        } elseif ( $tag == 'contributor' ) {
                                $revisionInfo['contributor'] = $this->handleContributor();
                        } elseif ( $tag != '#text' ) {
                                $this->warn( "Unhandled revision XML tag $tag" );
                                $skip = true;
                        }
                }

                $pageInfo['revisionCount']++;
                if ( $this->processRevision( $pageInfo, $revisionInfo ) ) {
                        $pageInfo['successfulRevisionCount']++;
                }
        }

        private function handleContent() {
                $this->debug( "Enter content handler" );
                $contentInfo = [];

                $normalFields = [ 'role', 'origin', 'model', 'format', 'text' ];

                $skip = false;

                while ( $skip ? $this->reader->next() : $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                $this->reader->localName == 'content' ) {
                                break;
                        }

                        $tag = $this->reader->localName;

                        if ( !$this->hookRunner->onImportHandleContentXMLTag(
                                $this, $contentInfo )
                        ) {
                                // Do nothing
                        } elseif ( in_array( $tag, $normalFields ) ) {
                                $contentInfo[$tag] = $this->nodeContents();
                        } elseif ( $tag != '#text' ) {
                                $this->warn( "Unhandled content XML tag $tag" );
                                $skip = true;
                        }
                }

                return $contentInfo;
        }

        /**
         * @param PageIdentity $page
         * @param int $revisionId
         * @param array $contentInfo
         *
         * @return Content
         */
        private function makeContent( PageIdentity $page, $revisionId, $contentInfo ) {
                $maxArticleSize = $this->config->get( MainConfigNames::MaxArticleSize );

                if ( !isset( $contentInfo['text'] ) ) {
                        throw new InvalidArgumentException( 'Missing text field in import.' );
                }

                // Make sure revisions won't violate $wgMaxArticleSize, which could lead to
                // database errors and instability. Testing for revisions with only listed
                // content models, as other content models might use serialization formats
                // which aren't checked against $wgMaxArticleSize.
                if ( ( !isset( $contentInfo['model'] ) ||
                                in_array( $contentInfo['model'], [
                                        'wikitext',
                                        'css',
                                        'json',
                                        'javascript',
                                        'text',
                                        ''
                                ] ) ) &&
                        strlen( $contentInfo['text'] ) > $maxArticleSize * 1024
                ) {
                        throw new RuntimeException( 'The text of ' .
                                ( $revisionId ?
                                        "the revision with ID $revisionId" :
                                        'a revision'
                                ) . " exceeds the maximum allowable size ({$maxArticleSize} KiB)" );
                }

                $role = $contentInfo['role'] ?? SlotRecord::MAIN;
                $model = $contentInfo['model'] ?? $this->slotRoleRegistry
                        ->getRoleHandler( $role )
                        ->getDefaultModel( $page );
                $handler = $this->contentHandlerFactory->getContentHandler( $model );

                $text = $handler->importTransform( $contentInfo['text'] );

                return $handler->unserializeContent( $text );
        }

        /**
         * @param array $pageInfo
         * @param array $revisionInfo
         * @return mixed|false
         */
        private function processRevision( $pageInfo, $revisionInfo ) {
                $revision = new WikiRevision();

                $revId = $revisionInfo['id'] ?? 0;
                if ( $revId ) {
                        $revision->setID( $revisionInfo['id'] );
                }

                $title = $pageInfo['_title'];
                $revision->setTitle( $title );

                $content = $this->makeContent( $title, $revId, $revisionInfo );
                $revision->setContent( SlotRecord::MAIN, $content );

                foreach ( $revisionInfo['content'] ?? [] as $slotInfo ) {
                        if ( !isset( $slotInfo['role'] ) ) {
                                throw new RuntimeException( "Missing role for imported slot." );
                        }

                        $content = $this->makeContent( $title, $revId, $slotInfo );
                        $revision->setContent( $slotInfo['role'], $content );
                }
                $revision->setTimestamp( $revisionInfo['timestamp'] ?? wfTimestampNow() );

                if ( isset( $revisionInfo['comment'] ) ) {
                        $revision->setComment( $revisionInfo['comment'] );
                }

                if ( isset( $revisionInfo['minor'] ) ) {
                        $revision->setMinor( true );
                }
                if ( isset( $revisionInfo['contributor']['username'] ) ) {
                        $revision->setUsername(
                                $this->externalUserNames->applyPrefix( $revisionInfo['contributor']['username'] )
                        );
                } elseif ( isset( $revisionInfo['contributor']['ip'] ) ) {
                        $revision->setUserIP( $revisionInfo['contributor']['ip'] );
                } else {
                        $revision->setUsername( $this->externalUserNames->addPrefix( 'Unknown user' ) );
                }
                if ( isset( $revisionInfo['sha1'] ) ) {
                        $revision->setSha1Base36( $revisionInfo['sha1'] );
                }
                $revision->setNoUpdates( $this->mNoUpdates );

                return $this->revisionCallback( $revision );
        }

        /**
         * @param array &$pageInfo
         * @return mixed
         */
        private function handleUpload( &$pageInfo ) {
                $this->debug( "Enter upload handler" );
                $uploadInfo = [];

                $normalFields = [ 'timestamp', 'comment', 'filename', 'text',
                        'src', 'size', 'sha1base36', 'archivename', 'rel' ];

                $skip = false;

                while ( $skip ? $this->reader->next() : $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                        $this->reader->localName == 'upload' ) {
                                break;
                        }

                        $tag = $this->reader->localName;

                        if ( !$this->hookRunner->onImportHandleUploadXMLTag( $this, $pageInfo ) ) {
                                // Do nothing
                        } elseif ( in_array( $tag, $normalFields ) ) {
                                $uploadInfo[$tag] = $this->nodeContents();
                        } elseif ( $tag == 'contributor' ) {
                                $uploadInfo['contributor'] = $this->handleContributor();
                        } elseif ( $tag == 'contents' ) {
                                $contents = $this->nodeContents();
                                $encoding = $this->reader->getAttribute( 'encoding' );
                                if ( $encoding === 'base64' ) {
                                        $uploadInfo['fileSrc'] = $this->dumpTemp( base64_decode( $contents ) );
                                        $uploadInfo['isTempSrc'] = true;
                                }
                        } elseif ( $tag != '#text' ) {
                                $this->warn( "Unhandled upload XML tag $tag" );
                                $skip = true;
                        }
                }

                if ( $this->mImageBasePath && isset( $uploadInfo['rel'] ) ) {
                        $path = "{$this->mImageBasePath}/{$uploadInfo['rel']}";
                        if ( file_exists( $path ) ) {
                                $uploadInfo['fileSrc'] = $path;
                                $uploadInfo['isTempSrc'] = false;
                        }
                }

                if ( $this->mImportUploads ) {
                        return $this->processUpload( $pageInfo, $uploadInfo );
                }
        }

        /**
         * @param string $contents
         * @return string
         */
        private function dumpTemp( $contents ) {
                $filename = tempnam( wfTempDir(), 'importupload' );
                file_put_contents( $filename, $contents );
                return $filename;
        }

        /**
         * @param array $pageInfo
         * @param array $uploadInfo
         * @return mixed
         */
        private function processUpload( $pageInfo, $uploadInfo ) {
                $revision = new WikiRevision();
                $revId = $pageInfo['id'];
                $title = $pageInfo['_title'];
                // T292348: text key may be absent, force addition if null
                $uploadInfo['text'] ??= '';
                $content = $this->makeContent( $title, $revId, $uploadInfo );

                $revision->setTitle( $title );
                $revision->setID( $revId );
                $revision->setTimestamp( $uploadInfo['timestamp'] );
                $revision->setContent( SlotRecord::MAIN, $content );
                $revision->setFilename( $uploadInfo['filename'] );
                if ( isset( $uploadInfo['archivename'] ) ) {
                        $revision->setArchiveName( $uploadInfo['archivename'] );
                }
                $revision->setSrc( $uploadInfo['src'] );
                if ( isset( $uploadInfo['fileSrc'] ) ) {
                        $revision->setFileSrc( $uploadInfo['fileSrc'],
                                !empty( $uploadInfo['isTempSrc'] )
                        );
                }
                if ( isset( $uploadInfo['sha1base36'] ) ) {
                        $revision->setSha1Base36( $uploadInfo['sha1base36'] );
                }
                $revision->setSize( intval( $uploadInfo['size'] ) );
                $revision->setComment( $uploadInfo['comment'] );

                if ( isset( $uploadInfo['contributor']['username'] ) ) {
                        $revision->setUsername(
                                $this->externalUserNames->applyPrefix( $uploadInfo['contributor']['username'] )
                        );
                } elseif ( isset( $uploadInfo['contributor']['ip'] ) ) {
                        $revision->setUserIP( $uploadInfo['contributor']['ip'] );
                }
                $revision->setNoUpdates( $this->mNoUpdates );

                return call_user_func( $this->mUploadCallback, $revision );
        }

        /**
         * @return array
         */
        private function handleContributor() {
                $this->debug( "Enter contributor handler." );

                if ( $this->reader->isEmptyElement ) {
                        return [];
                }

                $fields = [ 'id', 'ip', 'username' ];
                $info = [];

                while ( $this->reader->read() ) {
                        if ( $this->reader->nodeType == XMLReader::END_ELEMENT &&
                                        $this->reader->localName == 'contributor' ) {
                                break;
                        }

                        $tag = $this->reader->localName;

                        if ( in_array( $tag, $fields ) ) {
                                $info[$tag] = $this->nodeContents();
                        }
                }

                return $info;
        }

        /**
         * @param string $text
         * @param string|null $ns
         * @return array|false
         */
        private function processTitle( $text, $ns = null ) {
                if ( $this->foreignNamespaces === null ) {
                        $foreignTitleFactory = new NaiveForeignTitleFactory(
                                $this->contentLanguage
                        );
                } else {
                        $foreignTitleFactory = new NamespaceAwareForeignTitleFactory(
                                $this->foreignNamespaces );
                }

                $foreignTitle = $foreignTitleFactory->createForeignTitle( $text,
                        intval( $ns ) );

                $title = $this->importTitleFactory->createTitleFromForeignTitle(
                        $foreignTitle );

                if ( $title === null ) {
                        # Invalid page title? Ignore the page
                        $this->notice( 'import-error-invalid', $foreignTitle->getFullText() );
                        return false;
                } elseif ( $title->isExternal() ) {
                        $this->notice( 'import-error-interwiki', $title->getPrefixedText() );
                        return false;
                } elseif ( !$title->canExist() ) {
                        $this->notice( 'import-error-special', $title->getPrefixedText() );
                        return false;
                } elseif ( !$this->performer->definitelyCan( 'edit', $title ) ) {
                        # Do not import if the importing wiki user cannot edit this page
                        $this->notice( 'import-error-edit', $title->getPrefixedText() );
                        return false;
                }

                return [ $title, $foreignTitle ];
        }

        /**
         * Open the XMLReader connected to the source adapter id
         * @suppress PhanStaticCallToNonStatic, UnusedSuppression -- for PHP 7.4 support
         */
        private function openReader() {
                // Enable the entity loader, as it is needed for loading external URLs via
                // XMLReader::open (T86036)
                // phpcs:ignore Generic.PHP.NoSilencedErrors -- suppress deprecation per T268847
                $oldDisable = @libxml_disable_entity_loader( false );

                if ( PHP_VERSION_ID >= 80000 ) {
                        // A static call is now preferred, and avoids https://github.com/php/php-src/issues/11548
                        $reader = XMLReader::open(
                                'uploadsource://' . $this->sourceAdapterId, null, LIBXML_PARSEHUGE );
                        if ( $reader instanceof XMLReader ) {
                                $this->reader = $reader;
                                $status = true;
                        } else {
                                $status = false;
                        }
                } else {
                        // A static call generated a deprecation warning prior to PHP 8.0
                        $this->reader = new XMLReader;
                        $status = $this->reader->open(
                                'uploadsource://' . $this->sourceAdapterId, null, LIBXML_PARSEHUGE );
                }
                if ( !$status ) {
                        $error = libxml_get_last_error();
                        // phpcs:ignore Generic.PHP.NoSilencedErrors
                        @libxml_disable_entity_loader( $oldDisable );
                        throw new RuntimeException(
                                'Encountered an internal error while initializing WikiImporter object: ' . $error->message
                        );
                }
                // phpcs:ignore Generic.PHP.NoSilencedErrors
                @libxml_disable_entity_loader( $oldDisable );
        }

        /**
         * Check the syntax of the given xml
         */
        private function syntaxCheckXML() {
                if ( !UploadSourceAdapter::isSeekableSource( $this->sourceAdapterId ) ) {
                        return;
                }
                AtEase::suppressWarnings();
                $oldDisable = libxml_disable_entity_loader( false );
                try {
                        while ( $this->reader->read() );
                        $error = libxml_get_last_error();
                        if ( $error ) {
                                $errorMessage = 'XML error at line ' . $error->line . ': ' . $error->message;
                                wfDebug( __METHOD__ . ': Invalid xml found - ' . $errorMessage );
                                throw new RuntimeException( $errorMessage );
                        }
                } finally {
                        libxml_disable_entity_loader( $oldDisable );
                        AtEase::restoreWarnings();
                        $this->reader->close();
                }

                // Reopen for the real import
                UploadSourceAdapter::seekSource( $this->sourceAdapterId, 0 );
                $this->openReader();
        }
}