LocalFile.php

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<?php
use Wikimedia\AtEase\AtEase;
use MediaWiki\Logger\LoggerFactory;
use Wikimedia\Rdbms\Database;
use Wikimedia\Rdbms\IDatabase;
use Wikimedia\Rdbms\IResultWrapper;
use MediaWiki\MediaWikiServices;

class LocalFile extends File {
    const VERSION = 11; // cache version

    const CACHE_FIELD_MAX_LEN = 1000;

    protected $fileExists;

    protected $width;

    protected $height;

    protected $bits;

    protected $media_type;

    protected $mime;

    protected $size;

    protected $metadata;

    protected $sha1;

    protected $dataLoaded;

    protected $extraDataLoaded;

    protected $deleted;

    protected $repoClass = LocalRepo::class;

    private $historyLine;

    private $historyRes;

    private $major_mime;

    private $minor_mime;

    private $timestamp;

    private $user;

    private $description;

    private $descriptionTouched;

    private $upgraded;

    private $upgrading;

    private $locked;

    private $lockedOwnTrx;

    private $missing;

    // @note: higher than IDBAccessObject constants
    const LOAD_ALL = 16; // integer; load all the lazy fields too (like metadata)

    const ATOMIC_SECTION_LOCK = 'LocalFile::lockingTransaction';

    static function newFromTitle( $title, $repo, $unused = null ) {
        return new static( $title, $repo );
    }

    static function newFromRow( $row, $repo ) {
        $title = Title::makeTitle( NS_FILE, $row->img_name );
        $file = new static( $title, $repo );
        $file->loadFromRow( $row );

        return $file;
    }

    static function newFromKey( $sha1, $repo, $timestamp = false ) {
        $dbr = $repo->getReplicaDB();

        $conds = [ 'img_sha1' => $sha1 ];
        if ( $timestamp ) {
            $conds['img_timestamp'] = $dbr->timestamp( $timestamp );
        }

        $fileQuery = static::getQueryInfo();
        $row = $dbr->selectRow(
            $fileQuery['tables'], $fileQuery['fields'], $conds, __METHOD__, [], $fileQuery['joins']
        );
        if ( $row ) {
            return static::newFromRow( $row, $repo );
        } else {
            return false;
        }
    }

    static function selectFields() {
        global $wgActorTableSchemaMigrationStage;

        wfDeprecated( __METHOD__, '1.31' );
        if ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_READ_NEW ) {
            // If code is using this instead of self::getQueryInfo(), there's a
            // decent chance it's going to try to directly access
            // $row->img_user or $row->img_user_text and we can't give it
            // useful values here once those aren't being used anymore.
            throw new BadMethodCallException(
                'Cannot use ' . __METHOD__
                    . ' when $wgActorTableSchemaMigrationStage has SCHEMA_COMPAT_READ_NEW'
            );
        }

        return [
            'img_name',
            'img_size',
            'img_width',
            'img_height',
            'img_metadata',
            'img_bits',
            'img_media_type',
            'img_major_mime',
            'img_minor_mime',
            'img_user',
            'img_user_text',
            'img_actor' => 'NULL',
            'img_timestamp',
            'img_sha1',
        ] + MediaWikiServices::getInstance()->getCommentStore()->getFields( 'img_description' );
    }

    public static function getQueryInfo( array $options = [] ) {
        $commentQuery = MediaWikiServices::getInstance()->getCommentStore()->getJoin( 'img_description' );
        $actorQuery = ActorMigration::newMigration()->getJoin( 'img_user' );
        $ret = [
            'tables' => [ 'image' ] + $commentQuery['tables'] + $actorQuery['tables'],
            'fields' => [
                'img_name',
                'img_size',
                'img_width',
                'img_height',
                'img_metadata',
                'img_bits',
                'img_media_type',
                'img_major_mime',
                'img_minor_mime',
                'img_timestamp',
                'img_sha1',
            ] + $commentQuery['fields'] + $actorQuery['fields'],
            'joins' => $commentQuery['joins'] + $actorQuery['joins'],
        ];

        if ( in_array( 'omit-nonlazy', $options, true ) ) {
            // Internal use only for getting only the lazy fields
            $ret['fields'] = [];
        }
        if ( !in_array( 'omit-lazy', $options, true ) ) {
            // Note: Keep this in sync with self::getLazyCacheFields()
            $ret['fields'][] = 'img_metadata';
        }

        return $ret;
    }

    function __construct( $title, $repo ) {
        parent::__construct( $title, $repo );

        $this->metadata = '';
        $this->historyLine = 0;
        $this->historyRes = null;
        $this->dataLoaded = false;
        $this->extraDataLoaded = false;

        $this->assertRepoDefined();
        $this->assertTitleDefined();
    }

    function getCacheKey() {
        return $this->repo->getSharedCacheKey( 'file', sha1( $this->getName() ) );
    }

    public function getMutableCacheKeys( WANObjectCache $cache ) {
        return [ $this->getCacheKey() ];
    }

    private function loadFromCache() {
        $this->dataLoaded = false;
        $this->extraDataLoaded = false;

        $key = $this->getCacheKey();
        if ( !$key ) {
            $this->loadFromDB( self::READ_NORMAL );

            return;
        }

        $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
        $cachedValues = $cache->getWithSetCallback(
            $key,
            $cache::TTL_WEEK,
            function ( $oldValue, &$ttl, array &$setOpts ) use ( $cache ) {
                $setOpts += Database::getCacheSetOptions( $this->repo->getReplicaDB() );

                $this->loadFromDB( self::READ_NORMAL );

                $fields = $this->getCacheFields( '' );
                $cacheVal['fileExists'] = $this->fileExists;
                if ( $this->fileExists ) {
                    foreach ( $fields as $field ) {
                        $cacheVal[$field] = $this->$field;
                    }
                }
                $cacheVal['user'] = $this->user ? $this->user->getId() : 0;
                $cacheVal['user_text'] = $this->user ? $this->user->getName() : '';
                $cacheVal['actor'] = $this->user ? $this->user->getActorId() : null;

                // Strip off excessive entries from the subset of fields that can become large.
                // If the cache value gets to large it will not fit in memcached and nothing will
                // get cached at all, causing master queries for any file access.
                foreach ( $this->getLazyCacheFields( '' ) as $field ) {
                    if ( isset( $cacheVal[$field] )
                        && strlen( $cacheVal[$field] ) > 100 * 1024
                    ) {
                        unset( $cacheVal[$field] ); // don't let the value get too big
                    }
                }

                if ( $this->fileExists ) {
                    $ttl = $cache->adaptiveTTL( wfTimestamp( TS_UNIX, $this->timestamp ), $ttl );
                } else {
                    $ttl = $cache::TTL_DAY;
                }

                return $cacheVal;
            },
            [ 'version' => self::VERSION ]
        );

        $this->fileExists = $cachedValues['fileExists'];
        if ( $this->fileExists ) {
            $this->setProps( $cachedValues );
        }

        $this->dataLoaded = true;
        $this->extraDataLoaded = true;
        foreach ( $this->getLazyCacheFields( '' ) as $field ) {
            $this->extraDataLoaded = $this->extraDataLoaded && isset( $cachedValues[$field] );
        }
    }

    public function invalidateCache() {
        $key = $this->getCacheKey();
        if ( !$key ) {
            return;
        }

        $this->repo->getMasterDB()->onTransactionPreCommitOrIdle(
            function () use ( $key ) {
                MediaWikiServices::getInstance()->getMainWANObjectCache()->delete( $key );
            },
            __METHOD__
        );
    }

    function loadFromFile() {
        $props = $this->repo->getFileProps( $this->getVirtualUrl() );
        $this->setProps( $props );
    }

    protected function getCacheFields( $prefix = 'img_' ) {
        if ( $prefix !== '' ) {
            throw new InvalidArgumentException(
                __METHOD__ . ' with a non-empty prefix is no longer supported.'
            );
        }

        // See self::getQueryInfo() for the fetching of the data from the DB,
        // self::loadFromRow() for the loading of the object from the DB row,
        // and self::loadFromCache() for the caching, and self::setProps() for
        // populating the object from an array of data.
        return [ 'size', 'width', 'height', 'bits', 'media_type',
            'major_mime', 'minor_mime', 'metadata', 'timestamp', 'sha1', 'description' ];
    }

    protected function getLazyCacheFields( $prefix = 'img_' ) {
        if ( $prefix !== '' ) {
            throw new InvalidArgumentException(
                __METHOD__ . ' with a non-empty prefix is no longer supported.'
            );
        }

        // Keep this in sync with the omit-lazy option in self::getQueryInfo().
        return [ 'metadata' ];
    }

    function loadFromDB( $flags = 0 ) {
        $fname = static::class . '::' . __FUNCTION__;

        # Unconditionally set loaded=true, we don't want the accessors constantly rechecking
        $this->dataLoaded = true;
        $this->extraDataLoaded = true;

        $dbr = ( $flags & self::READ_LATEST )
            ? $this->repo->getMasterDB()
            : $this->repo->getReplicaDB();

        $fileQuery = static::getQueryInfo();
        $row = $dbr->selectRow(
            $fileQuery['tables'],
            $fileQuery['fields'],
            [ 'img_name' => $this->getName() ],
            $fname,
            [],
            $fileQuery['joins']
        );

        if ( $row ) {
            $this->loadFromRow( $row );
        } else {
            $this->fileExists = false;
        }
    }

    protected function loadExtraFromDB() {
        $fname = static::class . '::' . __FUNCTION__;

        # Unconditionally set loaded=true, we don't want the accessors constantly rechecking
        $this->extraDataLoaded = true;

        $fieldMap = $this->loadExtraFieldsWithTimestamp( $this->repo->getReplicaDB(), $fname );
        if ( !$fieldMap ) {
            $fieldMap = $this->loadExtraFieldsWithTimestamp( $this->repo->getMasterDB(), $fname );
        }

        if ( $fieldMap ) {
            foreach ( $fieldMap as $name => $value ) {
                $this->$name = $value;
            }
        } else {
            throw new MWException( "Could not find data for image '{$this->getName()}'." );
        }
    }

    private function loadExtraFieldsWithTimestamp( $dbr, $fname ) {
        $fieldMap = false;

        $fileQuery = self::getQueryInfo( [ 'omit-nonlazy' ] );
        $row = $dbr->selectRow(
            $fileQuery['tables'],
            $fileQuery['fields'],
            [
                'img_name' => $this->getName(),
                'img_timestamp' => $dbr->timestamp( $this->getTimestamp() ),
            ],
            $fname,
            [],
            $fileQuery['joins']
        );
        if ( $row ) {
            $fieldMap = $this->unprefixRow( $row, 'img_' );
        } else {
            # File may have been uploaded over in the meantime; check the old versions
            $fileQuery = OldLocalFile::getQueryInfo( [ 'omit-nonlazy' ] );
            $row = $dbr->selectRow(
                $fileQuery['tables'],
                $fileQuery['fields'],
                [
                    'oi_name' => $this->getName(),
                    'oi_timestamp' => $dbr->timestamp( $this->getTimestamp() ),
                ],
                $fname,
                [],
                $fileQuery['joins']
            );
            if ( $row ) {
                $fieldMap = $this->unprefixRow( $row, 'oi_' );
            }
        }

        if ( isset( $fieldMap['metadata'] ) ) {
            $fieldMap['metadata'] = $this->repo->getReplicaDB()->decodeBlob( $fieldMap['metadata'] );
        }

        return $fieldMap;
    }

    protected function unprefixRow( $row, $prefix = 'img_' ) {
        $array = (array)$row;
        $prefixLength = strlen( $prefix );

        // Sanity check prefix once
        if ( substr( key( $array ), 0, $prefixLength ) !== $prefix ) {
            throw new MWException( __METHOD__ . ': incorrect $prefix parameter' );
        }

        $decoded = [];
        foreach ( $array as $name => $value ) {
            $decoded[substr( $name, $prefixLength )] = $value;
        }

        return $decoded;
    }

    function decodeRow( $row, $prefix = 'img_' ) {
        $decoded = $this->unprefixRow( $row, $prefix );

        $decoded['description'] = MediaWikiServices::getInstance()->getCommentStore()
            ->getComment( 'description', (object)$decoded )->text;

        $decoded['user'] = User::newFromAnyId(
            $decoded['user'] ?? null,
            $decoded['user_text'] ?? null,
            $decoded['actor'] ?? null
        );
        unset( $decoded['user_text'], $decoded['actor'] );

        $decoded['timestamp'] = wfTimestamp( TS_MW, $decoded['timestamp'] );

        $decoded['metadata'] = $this->repo->getReplicaDB()->decodeBlob( $decoded['metadata'] );

        if ( empty( $decoded['major_mime'] ) ) {
            $decoded['mime'] = 'unknown/unknown';
        } else {
            if ( !$decoded['minor_mime'] ) {
                $decoded['minor_mime'] = 'unknown';
            }
            $decoded['mime'] = $decoded['major_mime'] . '/' . $decoded['minor_mime'];
        }

        // Trim zero padding from char/binary field
        $decoded['sha1'] = rtrim( $decoded['sha1'], "\0" );

        // Normalize some fields to integer type, per their database definition.
        // Use unary + so that overflows will be upgraded to double instead of
        // being trucated as with intval(). This is important to allow >2GB
        // files on 32-bit systems.
        foreach ( [ 'size', 'width', 'height', 'bits' ] as $field ) {
            $decoded[$field] = +$decoded[$field];
        }

        return $decoded;
    }

    function loadFromRow( $row, $prefix = 'img_' ) {
        $this->dataLoaded = true;
        $this->extraDataLoaded = true;

        $array = $this->decodeRow( $row, $prefix );

        foreach ( $array as $name => $value ) {
            $this->$name = $value;
        }

        $this->fileExists = true;
    }

    function load( $flags = 0 ) {
        if ( !$this->dataLoaded ) {
            if ( $flags & self::READ_LATEST ) {
                $this->loadFromDB( $flags );
            } else {
                $this->loadFromCache();
            }
        }

        if ( ( $flags & self::LOAD_ALL ) && !$this->extraDataLoaded ) {
            // @note: loads on name/timestamp to reduce race condition problems
            $this->loadExtraFromDB();
        }
    }

    protected function maybeUpgradeRow() {
        global $wgUpdateCompatibleMetadata;

        if ( wfReadOnly() || $this->upgrading ) {
            return;
        }

        $upgrade = false;
        if ( is_null( $this->media_type ) || $this->mime == 'image/svg' ) {
            $upgrade = true;
        } else {
            $handler = $this->getHandler();
            if ( $handler ) {
                $validity = $handler->isMetadataValid( $this, $this->getMetadata() );
                if ( $validity === MediaHandler::METADATA_BAD ) {
                    $upgrade = true;
                } elseif ( $validity === MediaHandler::METADATA_COMPATIBLE ) {
                    $upgrade = $wgUpdateCompatibleMetadata;
                }
            }
        }

        if ( $upgrade ) {
            $this->upgrading = true;
            // Defer updates unless in auto-commit CLI mode
            DeferredUpdates::addCallableUpdate( function () {
                $this->upgrading = false; // avoid duplicate updates
                try {
                    $this->upgradeRow();
                } catch ( LocalFileLockError $e ) {
                    // let the other process handle it (or do it next time)
                }
            } );
        }
    }

    function getUpgraded() {
        return $this->upgraded;
    }

    function upgradeRow() {
        $this->lock();

        $this->loadFromFile();

        # Don't destroy file info of missing files
        if ( !$this->fileExists ) {
            $this->unlock();
            wfDebug( __METHOD__ . ": file does not exist, aborting\n" );

            return;
        }

        $dbw = $this->repo->getMasterDB();
        list( $major, $minor ) = self::splitMime( $this->mime );

        if ( wfReadOnly() ) {
            $this->unlock();

            return;
        }
        wfDebug( __METHOD__ . ': upgrading ' . $this->getName() . " to the current schema\n" );

        $dbw->update( 'image',
            [
                'img_size' => $this->size, // sanity
                'img_width' => $this->width,
                'img_height' => $this->height,
                'img_bits' => $this->bits,
                'img_media_type' => $this->media_type,
                'img_major_mime' => $major,
                'img_minor_mime' => $minor,
                'img_metadata' => $dbw->encodeBlob( $this->metadata ),
                'img_sha1' => $this->sha1,
            ],
            [ 'img_name' => $this->getName() ],
            __METHOD__
        );

        $this->invalidateCache();

        $this->unlock();
        $this->upgraded = true; // avoid rework/retries
    }

    function setProps( $info ) {
        $this->dataLoaded = true;
        $fields = $this->getCacheFields( '' );
        $fields[] = 'fileExists';

        foreach ( $fields as $field ) {
            if ( isset( $info[$field] ) ) {
                $this->$field = $info[$field];
            }
        }

        if ( isset( $info['user'] ) || isset( $info['user_text'] ) || isset( $info['actor'] ) ) {
            $this->user = User::newFromAnyId(
                $info['user'] ?? null,
                $info['user_text'] ?? null,
                $info['actor'] ?? null
            );
        }

        // Fix up mime fields
        if ( isset( $info['major_mime'] ) ) {
            $this->mime = "{$info['major_mime']}/{$info['minor_mime']}";
        } elseif ( isset( $info['mime'] ) ) {
            $this->mime = $info['mime'];
            list( $this->major_mime, $this->minor_mime ) = self::splitMime( $this->mime );
        }
    }

    function isMissing() {
        if ( $this->missing === null ) {
            $fileExists = $this->repo->fileExists( $this->getVirtualUrl() );
            $this->missing = !$fileExists;
        }

        return $this->missing;
    }

    public function getWidth( $page = 1 ) {
        $page = (int)$page;
        if ( $page < 1 ) {
            $page = 1;
        }

        $this->load();

        if ( $this->isMultipage() ) {
            $handler = $this->getHandler();
            if ( !$handler ) {
                return 0;
            }
            $dim = $handler->getPageDimensions( $this, $page );
            if ( $dim ) {
                return $dim['width'];
            } else {
                // For non-paged media, the false goes through an
                // intval, turning failure into 0, so do same here.
                return 0;
            }
        } else {
            return $this->width;
        }
    }

    public function getHeight( $page = 1 ) {
        $page = (int)$page;
        if ( $page < 1 ) {
            $page = 1;
        }

        $this->load();

        if ( $this->isMultipage() ) {
            $handler = $this->getHandler();
            if ( !$handler ) {
                return 0;
            }
            $dim = $handler->getPageDimensions( $this, $page );
            if ( $dim ) {
                return $dim['height'];
            } else {
                // For non-paged media, the false goes through an
                // intval, turning failure into 0, so do same here.
                return 0;
            }
        } else {
            return $this->height;
        }
    }

    function getUser( $type = 'text' ) {
        $this->load();

        if ( $type === 'object' ) {
            return $this->user;
        } elseif ( $type === 'text' ) {
            return $this->user->getName();
        } elseif ( $type === 'id' ) {
            return $this->user->getId();
        }

        throw new MWException( "Unknown type '$type'." );
    }

    public function getDescriptionShortUrl() {
        $pageId = $this->title->getArticleID();

        if ( $pageId !== null ) {
            $url = $this->repo->makeUrl( [ 'curid' => $pageId ] );
            if ( $url !== false ) {
                return $url;
            }
        }
        return null;
    }

    function getMetadata() {
        $this->load( self::LOAD_ALL ); // large metadata is loaded in another step
        return $this->metadata;
    }

    function getBitDepth() {
        $this->load();

        return (int)$this->bits;
    }

    public function getSize() {
        $this->load();

        return $this->size;
    }

    function getMimeType() {
        $this->load();

        return $this->mime;
    }

    function getMediaType() {
        $this->load();

        return $this->media_type;
    }

    public function exists() {
        $this->load();

        return $this->fileExists;
    }

    function getThumbnails( $archiveName = false ) {
        if ( $archiveName ) {
            $dir = $this->getArchiveThumbPath( $archiveName );
        } else {
            $dir = $this->getThumbPath();
        }

        $backend = $this->repo->getBackend();
        $files = [ $dir ];
        try {
            $iterator = $backend->getFileList( [ 'dir' => $dir ] );
            foreach ( $iterator as $file ) {
                $files[] = $file;
            }
        } catch ( FileBackendError $e ) {
        } // suppress (T56674)

        return $files;
    }

    function purgeMetadataCache() {
        $this->invalidateCache();
    }

    function purgeCache( $options = [] ) {
        // Refresh metadata cache
        $this->maybeUpgradeRow();
        $this->purgeMetadataCache();

        // Delete thumbnails
        $this->purgeThumbnails( $options );

        // Purge CDN cache for this file
        DeferredUpdates::addUpdate(
            new CdnCacheUpdate( [ $this->getUrl() ] ),
            DeferredUpdates::PRESEND
        );
    }

    function purgeOldThumbnails( $archiveName ) {
        // Get a list of old thumbnails and URLs
        $files = $this->getThumbnails( $archiveName );

        // Purge any custom thumbnail caches
        Hooks::run( 'LocalFilePurgeThumbnails', [ $this, $archiveName ] );

        // Delete thumbnails
        $dir = array_shift( $files );
        $this->purgeThumbList( $dir, $files );

        // Purge the CDN
        $urls = [];
        foreach ( $files as $file ) {
            $urls[] = $this->getArchiveThumbUrl( $archiveName, $file );
        }
        DeferredUpdates::addUpdate( new CdnCacheUpdate( $urls ), DeferredUpdates::PRESEND );
    }

    public function purgeThumbnails( $options = [] ) {
        $files = $this->getThumbnails();
        // Always purge all files from CDN regardless of handler filters
        $urls = [];
        foreach ( $files as $file ) {
            $urls[] = $this->getThumbUrl( $file );
        }
        array_shift( $urls ); // don't purge directory

        // Give media handler a chance to filter the file purge list
        if ( !empty( $options['forThumbRefresh'] ) ) {
            $handler = $this->getHandler();
            if ( $handler ) {
                $handler->filterThumbnailPurgeList( $files, $options );
            }
        }

        // Purge any custom thumbnail caches
        Hooks::run( 'LocalFilePurgeThumbnails', [ $this, false ] );

        // Delete thumbnails
        $dir = array_shift( $files );
        $this->purgeThumbList( $dir, $files );

        // Purge the CDN
        DeferredUpdates::addUpdate( new CdnCacheUpdate( $urls ), DeferredUpdates::PRESEND );
    }

    public function prerenderThumbnails() {
        global $wgUploadThumbnailRenderMap;

        $jobs = [];

        $sizes = $wgUploadThumbnailRenderMap;
        rsort( $sizes );

        foreach ( $sizes as $size ) {
            if ( $this->isVectorized() || $this->getWidth() > $size ) {
                $jobs[] = new ThumbnailRenderJob(
                    $this->getTitle(),
                    [ 'transformParams' => [ 'width' => $size ] ]
                );
            }
        }

        if ( $jobs ) {
            JobQueueGroup::singleton()->lazyPush( $jobs );
        }
    }

    protected function purgeThumbList( $dir, $files ) {
        $fileListDebug = strtr(
            var_export( $files, true ),
            [ "\n" => '' ]
        );
        wfDebug( __METHOD__ . ": $fileListDebug\n" );

        $purgeList = [];
        foreach ( $files as $file ) {
            if ( $this->repo->supportsSha1URLs() ) {
                $reference = $this->getSha1();
            } else {
                $reference = $this->getName();
            }

            # Check that the reference (filename or sha1) is part of the thumb name
            # This is a basic sanity check to avoid erasing unrelated directories
            if ( strpos( $file, $reference ) !== false
                || strpos( $file, "-thumbnail" ) !== false // "short" thumb name
            ) {
                $purgeList[] = "{$dir}/{$file}";
            }
        }

        # Delete the thumbnails
        $this->repo->quickPurgeBatch( $purgeList );
        # Clear out the thumbnail directory if empty
        $this->repo->quickCleanDir( $dir );
    }

    function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
        $dbr = $this->repo->getReplicaDB();
        $oldFileQuery = OldLocalFile::getQueryInfo();

        $tables = $oldFileQuery['tables'];
        $fields = $oldFileQuery['fields'];
        $join_conds = $oldFileQuery['joins'];
        $conds = $opts = [];
        $eq = $inc ? '=' : '';
        $conds[] = "oi_name = " . $dbr->addQuotes( $this->title->getDBkey() );

        if ( $start ) {
            $conds[] = "oi_timestamp <$eq " . $dbr->addQuotes( $dbr->timestamp( $start ) );
        }

        if ( $end ) {
            $conds[] = "oi_timestamp >$eq " . $dbr->addQuotes( $dbr->timestamp( $end ) );
        }

        if ( $limit ) {
            $opts['LIMIT'] = $limit;
        }

        // Search backwards for time > x queries
        $order = ( !$start && $end !== null ) ? 'ASC' : 'DESC';
        $opts['ORDER BY'] = "oi_timestamp $order";
        $opts['USE INDEX'] = [ 'oldimage' => 'oi_name_timestamp' ];

        // Avoid PHP 7.1 warning from passing $this by reference
        $localFile = $this;
        Hooks::run( 'LocalFile::getHistory', [ &$localFile, &$tables, &$fields,
            &$conds, &$opts, &$join_conds ] );

        $res = $dbr->select( $tables, $fields, $conds, __METHOD__, $opts, $join_conds );
        $r = [];

        foreach ( $res as $row ) {
            $r[] = $this->repo->newFileFromRow( $row );
        }

        if ( $order == 'ASC' ) {
            $r = array_reverse( $r ); // make sure it ends up descending
        }

        return $r;
    }

    public function nextHistoryLine() {
        # Polymorphic function name to distinguish foreign and local fetches
        $fname = static::class . '::' . __FUNCTION__;

        $dbr = $this->repo->getReplicaDB();

        if ( $this->historyLine == 0 ) { // called for the first time, return line from cur
            $fileQuery = self::getQueryInfo();
            $this->historyRes = $dbr->select( $fileQuery['tables'],
                $fileQuery['fields'] + [
                    'oi_archive_name' => $dbr->addQuotes( '' ),
                    'oi_deleted' => 0,
                ],
                [ 'img_name' => $this->title->getDBkey() ],
                $fname,
                [],
                $fileQuery['joins']
            );

            if ( $dbr->numRows( $this->historyRes ) == 0 ) {
                $this->historyRes = null;

                return false;
            }
        } elseif ( $this->historyLine == 1 ) {
            $fileQuery = OldLocalFile::getQueryInfo();
            $this->historyRes = $dbr->select(
                $fileQuery['tables'],
                $fileQuery['fields'],
                [ 'oi_name' => $this->title->getDBkey() ],
                $fname,
                [ 'ORDER BY' => 'oi_timestamp DESC' ],
                $fileQuery['joins']
            );
        }
        $this->historyLine++;

        return $dbr->fetchObject( $this->historyRes );
    }

    public function resetHistory() {
        $this->historyLine = 0;

        if ( !is_null( $this->historyRes ) ) {
            $this->historyRes = null;
        }
    }

    function upload( $src, $comment, $pageText, $flags = 0, $props = false,
        $timestamp = false, $user = null, $tags = [],
        $createNullRevision = true, $revert = false
    ) {
        if ( $this->getRepo()->getReadOnlyReason() !== false ) {
            return $this->readOnlyFatalStatus();
        } elseif ( MediaWikiServices::getInstance()->getRevisionStore()->isReadOnly() ) {
            // Check this in advance to avoid writing to FileBackend and the file tables,
            // only to fail on insert the revision due to the text store being unavailable.
            return $this->readOnlyFatalStatus();
        }

        $srcPath = ( $src instanceof FSFile ) ? $src->getPath() : $src;
        if ( !$props ) {
            if ( FileRepo::isVirtualUrl( $srcPath )
                || FileBackend::isStoragePath( $srcPath )
            ) {
                $props = $this->repo->getFileProps( $srcPath );
            } else {
                $mwProps = new MWFileProps( MediaWikiServices::getInstance()->getMimeAnalyzer() );
                $props = $mwProps->getPropsFromPath( $srcPath, true );
            }
        }

        $options = [];
        $handler = MediaHandler::getHandler( $props['mime'] );
        if ( $handler ) {
            $metadata = AtEase::quietCall( 'unserialize', $props['metadata'] );

            if ( !is_array( $metadata ) ) {
                $metadata = [];
            }

            $options['headers'] = $handler->getContentHeaders( $metadata );
        } else {
            $options['headers'] = [];
        }

        // Trim spaces on user supplied text
        $comment = trim( $comment );

        $this->lock();
        $status = $this->publish( $src, $flags, $options );

        if ( $status->successCount >= 2 ) {
            // There will be a copy+(one of move,copy,store).
            // The first succeeding does not commit us to updating the DB
            // since it simply copied the current version to a timestamped file name.
            // It is only *preferable* to avoid leaving such files orphaned.
            // Once the second operation goes through, then the current version was
            // updated and we must therefore update the DB too.
            $oldver = $status->value;
            $uploadStatus = $this->recordUpload2(
                $oldver,
                $comment,
                $pageText,
                $props,
                $timestamp,
                $user,
                $tags,
                $createNullRevision,
                $revert
            );
            if ( !$uploadStatus->isOK() ) {
                if ( $uploadStatus->hasMessage( 'filenotfound' ) ) {
                    // update filenotfound error with more specific path
                    $status->fatal( 'filenotfound', $srcPath );
                } else {
                    $status->merge( $uploadStatus );
                }
            }
        }

        $this->unlock();
        return $status;
    }

    function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
        $watch = false, $timestamp = false, User $user = null ) {
        if ( !$user ) {
            global $wgUser;
            $user = $wgUser;
        }

        $pageText = SpecialUpload::getInitialPageText( $desc, $license, $copyStatus, $source );

        if ( !$this->recordUpload2( $oldver, $desc, $pageText, false, $timestamp, $user )->isOK() ) {
            return false;
        }

        if ( $watch ) {
            $user->addWatch( $this->getTitle() );
        }

        return true;
    }

    function recordUpload2(
        $oldver, $comment, $pageText, $props = false, $timestamp = false, $user = null, $tags = [],
        $createNullRevision = true, $revert = false
    ) {
        global $wgActorTableSchemaMigrationStage;

        if ( is_null( $user ) ) {
            global $wgUser;
            $user = $wgUser;
        }

        $dbw = $this->repo->getMasterDB();

        # Imports or such might force a certain timestamp; otherwise we generate
        # it and can fudge it slightly to keep (name,timestamp) unique on re-upload.
        if ( $timestamp === false ) {
            $timestamp = $dbw->timestamp();
            $allowTimeKludge = true;
        } else {
            $allowTimeKludge = false;
        }

        $props = $props ?: $this->repo->getFileProps( $this->getVirtualUrl() );
        $props['description'] = $comment;
        $props['user'] = $user->getId();
        $props['user_text'] = $user->getName();
        $props['actor'] = $user->getActorId( $dbw );
        $props['timestamp'] = wfTimestamp( TS_MW, $timestamp ); // DB -> TS_MW
        $this->setProps( $props );

        # Fail now if the file isn't there
        if ( !$this->fileExists ) {
            wfDebug( __METHOD__ . ": File " . $this->getRel() . " went missing!\n" );

            return Status::newFatal( 'filenotfound', $this->getRel() );
        }

        $dbw->startAtomic( __METHOD__ );

        # Test to see if the row exists using INSERT IGNORE
        # This avoids race conditions by locking the row until the commit, and also
        # doesn't deadlock. SELECT FOR UPDATE causes a deadlock for every race condition.
        $commentStore = MediaWikiServices::getInstance()->getCommentStore();
        $commentFields = $commentStore->insert( $dbw, 'img_description', $comment );
        $actorMigration = ActorMigration::newMigration();
        $actorFields = $actorMigration->getInsertValues( $dbw, 'img_user', $user );
        $dbw->insert( 'image',
            [
                'img_name' => $this->getName(),
                'img_size' => $this->size,
                'img_width' => intval( $this->width ),
                'img_height' => intval( $this->height ),
                'img_bits' => $this->bits,
                'img_media_type' => $this->media_type,
                'img_major_mime' => $this->major_mime,
                'img_minor_mime' => $this->minor_mime,
                'img_timestamp' => $timestamp,
                'img_metadata' => $dbw->encodeBlob( $this->metadata ),
                'img_sha1' => $this->sha1
            ] + $commentFields + $actorFields,
            __METHOD__,
            [ 'IGNORE' ]
        );
        $reupload = ( $dbw->affectedRows() == 0 );

        if ( $reupload ) {
            $row = $dbw->selectRow(
                'image',
                [ 'img_timestamp', 'img_sha1' ],
                [ 'img_name' => $this->getName() ],
                __METHOD__,
                [ 'LOCK IN SHARE MODE' ]
            );

            if ( $row && $row->img_sha1 === $this->sha1 ) {
                $dbw->endAtomic( __METHOD__ );
                wfDebug( __METHOD__ . ": File " . $this->getRel() . " already exists!\n" );
                $title = Title::newFromText( $this->getName(), NS_FILE );
                return Status::newFatal( 'fileexists-no-change', $title->getPrefixedText() );
            }

            if ( $allowTimeKludge ) {
                # Use LOCK IN SHARE MODE to ignore any transaction snapshotting
                $lUnixtime = $row ? wfTimestamp( TS_UNIX, $row->img_timestamp ) : false;
                # Avoid a timestamp that is not newer than the last version
                # TODO: the image/oldimage tables should be like page/revision with an ID field
                if ( $lUnixtime && wfTimestamp( TS_UNIX, $timestamp ) <= $lUnixtime ) {
                    sleep( 1 ); // fast enough re-uploads would go far in the future otherwise
                    $timestamp = $dbw->timestamp( $lUnixtime + 1 );
                    $this->timestamp = wfTimestamp( TS_MW, $timestamp ); // DB -> TS_MW
                }
            }

            $tables = [ 'image' ];
            $fields = [
                'oi_name' => 'img_name',
                'oi_archive_name' => $dbw->addQuotes( $oldver ),
                'oi_size' => 'img_size',
                'oi_width' => 'img_width',
                'oi_height' => 'img_height',
                'oi_bits' => 'img_bits',
                'oi_description_id' => 'img_description_id',
                'oi_timestamp' => 'img_timestamp',
                'oi_metadata' => 'img_metadata',
                'oi_media_type' => 'img_media_type',
                'oi_major_mime' => 'img_major_mime',
                'oi_minor_mime' => 'img_minor_mime',
                'oi_sha1' => 'img_sha1',
            ];
            $joins = [];

            if ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_WRITE_OLD ) {
                $fields['oi_user'] = 'img_user';
                $fields['oi_user_text'] = 'img_user_text';
            }
            if ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_WRITE_NEW ) {
                $fields['oi_actor'] = 'img_actor';
            }

            if (
                ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_WRITE_BOTH ) === SCHEMA_COMPAT_WRITE_BOTH
            ) {
                // Upgrade any rows that are still old-style. Otherwise an upgrade
                // might be missed if a deletion happens while the migration script
                // is running.
                $res = $dbw->select(
                    [ 'image' ],
                    [ 'img_name', 'img_user', 'img_user_text' ],
                    [ 'img_name' => $this->getName(), 'img_actor' => 0 ],
                    __METHOD__
                );
                foreach ( $res as $row ) {
                    $actorId = User::newFromAnyId( $row->img_user, $row->img_user_text, null )->getActorId( $dbw );
                    $dbw->update(
                        'image',
                        [ 'img_actor' => $actorId ],
                        [ 'img_name' => $row->img_name, 'img_actor' => 0 ],
                        __METHOD__
                    );
                }
            }

            # (T36993) Note: $oldver can be empty here, if the previous
            # version of the file was broken. Allow registration of the new
            # version to continue anyway, because that's better than having
            # an image that's not fixable by user operations.
            # Collision, this is an update of a file
            # Insert previous contents into oldimage
            $dbw->insertSelect( 'oldimage', $tables, $fields,
                [ 'img_name' => $this->getName() ], __METHOD__, [], [], $joins );

            # Update the current image row
            $dbw->update( 'image',
                [
                    'img_size' => $this->size,
                    'img_width' => intval( $this->width ),
                    'img_height' => intval( $this->height ),
                    'img_bits' => $this->bits,
                    'img_media_type' => $this->media_type,
                    'img_major_mime' => $this->major_mime,
                    'img_minor_mime' => $this->minor_mime,
                    'img_timestamp' => $timestamp,
                    'img_metadata' => $dbw->encodeBlob( $this->metadata ),
                    'img_sha1' => $this->sha1
                ] + $commentFields + $actorFields,
                [ 'img_name' => $this->getName() ],
                __METHOD__
            );
        }

        $descTitle = $this->getTitle();
        $descId = $descTitle->getArticleID();
        $wikiPage = new WikiFilePage( $descTitle );
        $wikiPage->setFile( $this );

        // Determine log action. If reupload is done by reverting, use a special log_action.
        if ( $revert === true ) {
            $logAction = 'revert';
        } elseif ( $reupload === true ) {
            $logAction = 'overwrite';
        } else {
            $logAction = 'upload';
        }
        // Add the log entry...
        $logEntry = new ManualLogEntry( 'upload', $logAction );
        $logEntry->setTimestamp( $this->timestamp );
        $logEntry->setPerformer( $user );
        $logEntry->setComment( $comment );
        $logEntry->setTarget( $descTitle );
        // Allow people using the api to associate log entries with the upload.
        // Log has a timestamp, but sometimes different from upload timestamp.
        $logEntry->setParameters(
            [
                'img_sha1' => $this->sha1,
                'img_timestamp' => $timestamp,
            ]
        );
        // Note we keep $logId around since during new image
        // creation, page doesn't exist yet, so log_page = 0
        // but we want it to point to the page we're making,
        // so we later modify the log entry.
        // For a similar reason, we avoid making an RC entry
        // now and wait until the page exists.
        $logId = $logEntry->insert();

        if ( $descTitle->exists() ) {
            // Use own context to get the action text in content language
            $formatter = LogFormatter::newFromEntry( $logEntry );
            $formatter->setContext( RequestContext::newExtraneousContext( $descTitle ) );
            $editSummary = $formatter->getPlainActionText();

            $nullRevision = $createNullRevision === false ? null : Revision::newNullRevision(
                $dbw,
                $descId,
                $editSummary,
                false,
                $user
            );
            if ( $nullRevision ) {
                $nullRevision->insertOn( $dbw );
                Hooks::run(
                    'NewRevisionFromEditComplete',
                    [ $wikiPage, $nullRevision, $nullRevision->getParentId(), $user ]
                );
                $wikiPage->updateRevisionOn( $dbw, $nullRevision );
                // Associate null revision id
                $logEntry->setAssociatedRevId( $nullRevision->getId() );
            }

            $newPageContent = null;
        } else {
            // Make the description page and RC log entry post-commit
            $newPageContent = ContentHandler::makeContent( $pageText, $descTitle );
        }

        # Defer purges, page creation, and link updates in case they error out.
        # The most important thing is that files and the DB registry stay synced.
        $dbw->endAtomic( __METHOD__ );
        $fname = __METHOD__;

        # Do some cache purges after final commit so that:
        # a) Changes are more likely to be seen post-purge
        # b) They won't cause rollback of the log publish/update above
        DeferredUpdates::addUpdate(
            new AutoCommitUpdate(
                $dbw,
                __METHOD__,
                function () use (
                    $reupload, $wikiPage, $newPageContent, $comment, $user,
                    $logEntry, $logId, $descId, $tags, $fname
                ) {
                    # Update memcache after the commit
                    $this->invalidateCache();

                    $updateLogPage = false;
                    if ( $newPageContent ) {
                        # New file page; create the description page.
                        # There's already a log entry, so don't make a second RC entry
                        # CDN and file cache for the description page are purged by doEditContent.
                        $status = $wikiPage->doEditContent(
                            $newPageContent,
                            $comment,
                            EDIT_NEW | EDIT_SUPPRESS_RC,
                            false,
                            $user
                        );

                        if ( isset( $status->value['revision'] ) ) {
                            $rev = $status->value['revision'];
                            // Associate new page revision id
                            $logEntry->setAssociatedRevId( $rev->getId() );
                        }
                        // This relies on the resetArticleID() call in WikiPage::insertOn(),
                        // which is triggered on $descTitle by doEditContent() above.
                        if ( isset( $status->value['revision'] ) ) {
                            $rev = $status->value['revision'];
                            $updateLogPage = $rev->getPage();
                        }
                    } else {
                        # Existing file page: invalidate description page cache
                        $wikiPage->getTitle()->invalidateCache();
                        $wikiPage->getTitle()->purgeSquid();
                        # Allow the new file version to be patrolled from the page footer
                        Article::purgePatrolFooterCache( $descId );
                    }

                    # Update associated rev id. This should be done by $logEntry->insert() earlier,
                    # but setAssociatedRevId() wasn't called at that point yet...
                    $logParams = $logEntry->getParameters();
                    $logParams['associated_rev_id'] = $logEntry->getAssociatedRevId();
                    $update = [ 'log_params' => LogEntryBase::makeParamBlob( $logParams ) ];
                    if ( $updateLogPage ) {
                        # Also log page, in case where we just created it above
                        $update['log_page'] = $updateLogPage;
                    }
                    $this->getRepo()->getMasterDB()->update(
                        'logging',
                        $update,
                        [ 'log_id' => $logId ],
                        $fname
                    );
                    $this->getRepo()->getMasterDB()->insert(
                        'log_search',
                        [
                            'ls_field' => 'associated_rev_id',
                            'ls_value' => $logEntry->getAssociatedRevId(),
                            'ls_log_id' => $logId,
                        ],
                        $fname
                    );

                    # Add change tags, if any
                    if ( $tags ) {
                        $logEntry->setTags( $tags );
                    }

                    # Uploads can be patrolled
                    $logEntry->setIsPatrollable( true );

                    # Now that the log entry is up-to-date, make an RC entry.
                    $logEntry->publish( $logId );

                    # Run hook for other updates (typically more cache purging)
                    Hooks::run( 'FileUpload', [ $this, $reupload, !$newPageContent ] );

                    if ( $reupload ) {
                        # Delete old thumbnails
                        $this->purgeThumbnails();
                        # Remove the old file from the CDN cache
                        DeferredUpdates::addUpdate(
                            new CdnCacheUpdate( [ $this->getUrl() ] ),
                            DeferredUpdates::PRESEND
                        );
                    } else {
                        # Update backlink pages pointing to this title if created
                        LinksUpdate::queueRecursiveJobsForTable(
                            $this->getTitle(),
                            'imagelinks',
                            'upload-image',
                            $user->getName()
                        );
                    }

                    $this->prerenderThumbnails();
                }
            ),
            DeferredUpdates::PRESEND
        );

        if ( !$reupload ) {
            # This is a new file, so update the image count
            DeferredUpdates::addUpdate( SiteStatsUpdate::factory( [ 'images' => 1 ] ) );
        }

        # Invalidate cache for all pages using this file
        DeferredUpdates::addUpdate(
            new HTMLCacheUpdate( $this->getTitle(), 'imagelinks', 'file-upload' )
        );

        return Status::newGood();
    }

    function publish( $src, $flags = 0, array $options = [] ) {
        return $this->publishTo( $src, $this->getRel(), $flags, $options );
    }

    function publishTo( $src, $dstRel, $flags = 0, array $options = [] ) {
        $srcPath = ( $src instanceof FSFile ) ? $src->getPath() : $src;

        $repo = $this->getRepo();
        if ( $repo->getReadOnlyReason() !== false ) {
            return $this->readOnlyFatalStatus();
        }

        $this->lock();

        if ( $this->isOld() ) {
            $archiveRel = $dstRel;
            $archiveName = basename( $archiveRel );
        } else {
            $archiveName = wfTimestamp( TS_MW ) . '!' . $this->getName();
            $archiveRel = $this->getArchiveRel( $archiveName );
        }

        if ( $repo->hasSha1Storage() ) {
            $sha1 = FileRepo::isVirtualUrl( $srcPath )
                ? $repo->getFileSha1( $srcPath )
                : FSFile::getSha1Base36FromPath( $srcPath );
            $wrapperBackend = $repo->getBackend();
            $dst = $wrapperBackend->getPathForSHA1( $sha1 );
            $status = $repo->quickImport( $src, $dst );
            if ( $flags & File::DELETE_SOURCE ) {
                unlink( $srcPath );
            }

            if ( $this->exists() ) {
                $status->value = $archiveName;
            }
        } else {
            $flags = $flags & File::DELETE_SOURCE ? LocalRepo::DELETE_SOURCE : 0;
            $status = $repo->publish( $srcPath, $dstRel, $archiveRel, $flags, $options );

            if ( $status->value == 'new' ) {
                $status->value = '';
            } else {
                $status->value = $archiveName;
            }
        }

        $this->unlock();
        return $status;
    }

    function move( $target ) {
        $localRepo = MediaWikiServices::getInstance()->getRepoGroup()->getLocalRepo();
        if ( $this->getRepo()->getReadOnlyReason() !== false ) {
            return $this->readOnlyFatalStatus();
        }

        wfDebugLog( 'imagemove', "Got request to move {$this->name} to " . $target->getText() );
        $batch = new LocalFileMoveBatch( $this, $target );

        $this->lock();
        $batch->addCurrent();
        $archiveNames = $batch->addOlds();
        $status = $batch->execute();
        $this->unlock();

        wfDebugLog( 'imagemove', "Finished moving {$this->name}" );

        // Purge the source and target files...
        $oldTitleFile = $localRepo->newFile( $this->title );
        $newTitleFile = $localRepo->newFile( $target );
        // To avoid slow purges in the transaction, move them outside...
        DeferredUpdates::addUpdate(
            new AutoCommitUpdate(
                $this->getRepo()->getMasterDB(),
                __METHOD__,
                function () use ( $oldTitleFile, $newTitleFile, $archiveNames ) {
                    $oldTitleFile->purgeEverything();
                    foreach ( $archiveNames as $archiveName ) {
                        $oldTitleFile->purgeOldThumbnails( $archiveName );
                    }
                    $newTitleFile->purgeEverything();
                }
            ),
            DeferredUpdates::PRESEND
        );

        if ( $status->isOK() ) {
            // Now switch the object
            $this->title = $target;
            // Force regeneration of the name and hashpath
            unset( $this->name );
            unset( $this->hashPath );
        }

        return $status;
    }

    function delete( $reason, $suppress = false, $user = null ) {
        if ( $this->getRepo()->getReadOnlyReason() !== false ) {
            return $this->readOnlyFatalStatus();
        }

        $batch = new LocalFileDeleteBatch( $this, $reason, $suppress, $user );

        $this->lock();
        $batch->addCurrent();
        // Get old version relative paths
        $archiveNames = $batch->addOlds();
        $status = $batch->execute();
        $this->unlock();

        if ( $status->isOK() ) {
            DeferredUpdates::addUpdate( SiteStatsUpdate::factory( [ 'images' => -1 ] ) );
        }

        // To avoid slow purges in the transaction, move them outside...
        DeferredUpdates::addUpdate(
            new AutoCommitUpdate(
                $this->getRepo()->getMasterDB(),
                __METHOD__,
                function () use ( $archiveNames ) {
                    $this->purgeEverything();
                    foreach ( $archiveNames as $archiveName ) {
                        $this->purgeOldThumbnails( $archiveName );
                    }
                }
            ),
            DeferredUpdates::PRESEND
        );

        // Purge the CDN
        $purgeUrls = [];
        foreach ( $archiveNames as $archiveName ) {
            $purgeUrls[] = $this->getArchiveUrl( $archiveName );
        }
        DeferredUpdates::addUpdate( new CdnCacheUpdate( $purgeUrls ), DeferredUpdates::PRESEND );

        return $status;
    }

    function deleteOld( $archiveName, $reason, $suppress = false, $user = null ) {
        if ( $this->getRepo()->getReadOnlyReason() !== false ) {
            return $this->readOnlyFatalStatus();
        }

        $batch = new LocalFileDeleteBatch( $this, $reason, $suppress, $user );

        $this->lock();
        $batch->addOld( $archiveName );
        $status = $batch->execute();
        $this->unlock();

        $this->purgeOldThumbnails( $archiveName );
        if ( $status->isOK() ) {
            $this->purgeDescription();
        }

        DeferredUpdates::addUpdate(
            new CdnCacheUpdate( [ $this->getArchiveUrl( $archiveName ) ] ),
            DeferredUpdates::PRESEND
        );

        return $status;
    }

    function restore( $versions = [], $unsuppress = false ) {
        if ( $this->getRepo()->getReadOnlyReason() !== false ) {
            return $this->readOnlyFatalStatus();
        }

        $batch = new LocalFileRestoreBatch( $this, $unsuppress );

        $this->lock();
        if ( !$versions ) {
            $batch->addAll();
        } else {
            $batch->addIds( $versions );
        }
        $status = $batch->execute();
        if ( $status->isGood() ) {
            $cleanupStatus = $batch->cleanup();
            $cleanupStatus->successCount = 0;
            $cleanupStatus->failCount = 0;
            $status->merge( $cleanupStatus );
        }

        $this->unlock();
        return $status;
    }

    function getDescriptionUrl() {
        return $this->title->getLocalURL();
    }

    function getDescriptionText( Language $lang = null ) {
        $store = MediaWikiServices::getInstance()->getRevisionStore();
        $revision = $store->getRevisionByTitle( $this->title, 0, Revision::READ_NORMAL );
        if ( !$revision ) {
            return false;
        }

        $renderer = MediaWikiServices::getInstance()->getRevisionRenderer();
        $rendered = $renderer->getRenderedRevision( $revision, new ParserOptions( null, $lang ) );

        if ( !$rendered ) {
            // audience check failed
            return false;
        }

        $pout = $rendered->getRevisionParserOutput();
        return $pout->getText();
    }

    function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
        $this->load();
        if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
            return '';
        } elseif ( $audience == self::FOR_THIS_USER
            && !$this->userCan( self::DELETED_COMMENT, $user )
        ) {
            return '';
        } else {
            return $this->description;
        }
    }

    function getTimestamp() {
        $this->load();

        return $this->timestamp;
    }

    public function getDescriptionTouched() {
        // The DB lookup might return false, e.g. if the file was just deleted, or the shared DB repo
        // itself gets it from elsewhere. To avoid repeating the DB lookups in such a case, we
        // need to differentiate between null (uninitialized) and false (failed to load).
        if ( $this->descriptionTouched === null ) {
            $cond = [
                'page_namespace' => $this->title->getNamespace(),
                'page_title' => $this->title->getDBkey()
            ];
            $touched = $this->repo->getReplicaDB()->selectField( 'page', 'page_touched', $cond, __METHOD__ );
            $this->descriptionTouched = $touched ? wfTimestamp( TS_MW, $touched ) : false;
        }

        return $this->descriptionTouched;
    }

    function getSha1() {
        $this->load();
        // Initialise now if necessary
        if ( $this->sha1 == '' && $this->fileExists ) {
            $this->lock();

            $this->sha1 = $this->repo->getFileSha1( $this->getPath() );
            if ( !wfReadOnly() && strval( $this->sha1 ) != '' ) {
                $dbw = $this->repo->getMasterDB();
                $dbw->update( 'image',
                    [ 'img_sha1' => $this->sha1 ],
                    [ 'img_name' => $this->getName() ],
                    __METHOD__ );
                $this->invalidateCache();
            }

            $this->unlock();
        }

        return $this->sha1;
    }

    function isCacheable() {
        $this->load();

        // If extra data (metadata) was not loaded then it must have been large
        return $this->extraDataLoaded
            && strlen( serialize( $this->metadata ) ) <= self::CACHE_FIELD_MAX_LEN;
    }

    public function acquireFileLock() {
        return Status::wrap( $this->getRepo()->getBackend()->lockFiles(
            [ $this->getPath() ], LockManager::LOCK_EX, 10
        ) );
    }

    public function releaseFileLock() {
        return Status::wrap( $this->getRepo()->getBackend()->unlockFiles(
            [ $this->getPath() ], LockManager::LOCK_EX
        ) );
    }

    public function lock() {
        if ( !$this->locked ) {
            $logger = LoggerFactory::getInstance( 'LocalFile' );

            $dbw = $this->repo->getMasterDB();
            $makesTransaction = !$dbw->trxLevel();
            $dbw->startAtomic( self::ATOMIC_SECTION_LOCK );
            // T56736: use simple lock to handle when the file does not exist.
            // SELECT FOR UPDATE prevents changes, not other SELECTs with FOR UPDATE.
            // Also, that would cause contention on INSERT of similarly named rows.
            $status = $this->acquireFileLock(); // represents all versions of the file
            if ( !$status->isGood() ) {
                $dbw->endAtomic( self::ATOMIC_SECTION_LOCK );
                $logger->warning( "Failed to lock '{file}'", [ 'file' => $this->name ] );

                throw new LocalFileLockError( $status );
            }
            // Release the lock *after* commit to avoid row-level contention.
            // Make sure it triggers on rollback() as well as commit() (T132921).
            $dbw->onTransactionResolution(
                function () use ( $logger ) {
                    $status = $this->releaseFileLock();
                    if ( !$status->isGood() ) {
                        $logger->error( "Failed to unlock '{file}'", [ 'file' => $this->name ] );
                    }
                },
                __METHOD__
            );
            // Callers might care if the SELECT snapshot is safely fresh
            $this->lockedOwnTrx = $makesTransaction;
        }

        $this->locked++;

        return $this->lockedOwnTrx;
    }

    public function unlock() {
        if ( $this->locked ) {
            --$this->locked;
            if ( !$this->locked ) {
                $dbw = $this->repo->getMasterDB();
                $dbw->endAtomic( self::ATOMIC_SECTION_LOCK );
                $this->lockedOwnTrx = false;
            }
        }
    }

    protected function readOnlyFatalStatus() {
        return $this->getRepo()->newFatal( 'filereadonlyerror', $this->getName(),
            $this->getRepo()->getName(), $this->getRepo()->getReadOnlyReason() );
    }

    function __destruct() {
        $this->unlock();
    }
}