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Diffstat (limited to 'www/wiki/includes/libs/filebackend/FileBackendMultiWrite.php')
-rw-r--r-- | www/wiki/includes/libs/filebackend/FileBackendMultiWrite.php | 758 |
1 files changed, 758 insertions, 0 deletions
diff --git a/www/wiki/includes/libs/filebackend/FileBackendMultiWrite.php b/www/wiki/includes/libs/filebackend/FileBackendMultiWrite.php new file mode 100644 index 00000000..9c367af5 --- /dev/null +++ b/www/wiki/includes/libs/filebackend/FileBackendMultiWrite.php @@ -0,0 +1,758 @@ +<?php +/** + * Proxy backend that mirrors writes to several internal backends. + * + * 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 FileBackend + */ + +/** + * @brief Proxy backend that mirrors writes to several internal backends. + * + * This class defines a multi-write backend. Multiple backends can be + * registered to this proxy backend and it will act as a single backend. + * Use this when all access to those backends is through this proxy backend. + * At least one of the backends must be declared the "master" backend. + * + * Only use this class when transitioning from one storage system to another. + * + * Read operations are only done on the 'master' backend for consistency. + * Write operations are performed on all backends, starting with the master. + * This makes a best-effort to have transactional semantics, but since requests + * may sometimes fail, the use of "autoResync" or background scripts to fix + * inconsistencies is important. + * + * @ingroup FileBackend + * @since 1.19 + */ +class FileBackendMultiWrite extends FileBackend { + /** @var FileBackendStore[] Prioritized list of FileBackendStore objects */ + protected $backends = []; + + /** @var int Index of master backend */ + protected $masterIndex = -1; + /** @var int Index of read affinity backend */ + protected $readIndex = -1; + + /** @var int Bitfield */ + protected $syncChecks = 0; + /** @var string|bool */ + protected $autoResync = false; + + /** @var bool */ + protected $asyncWrites = false; + + /* Possible internal backend consistency checks */ + const CHECK_SIZE = 1; + const CHECK_TIME = 2; + const CHECK_SHA1 = 4; + + /** + * Construct a proxy backend that consists of several internal backends. + * Locking, journaling, and read-only checks are handled by the proxy backend. + * + * Additional $config params include: + * - backends : Array of backend config and multi-backend settings. + * Each value is the config used in the constructor of a + * FileBackendStore class, but with these additional settings: + * - class : The name of the backend class + * - isMultiMaster : This must be set for one backend. + * - readAffinity : Use this for reads without 'latest' set. + * - syncChecks : Integer bitfield of internal backend sync checks to perform. + * Possible bits include the FileBackendMultiWrite::CHECK_* constants. + * There are constants for SIZE, TIME, and SHA1. + * The checks are done before allowing any file operations. + * - autoResync : Automatically resync the clone backends to the master backend + * when pre-operation sync checks fail. This should only be used + * if the master backend is stable and not missing any files. + * Use "conservative" to limit resyncing to copying newer master + * backend files over older (or non-existing) clone backend files. + * Cases that cannot be handled will result in operation abortion. + * - replication : Set to 'async' to defer file operations on the non-master backends. + * This will apply such updates post-send for web requests. Note that + * any checks from "syncChecks" are still synchronous. + * + * Bogus warning + * @suppress PhanAccessMethodProtected + * + * @param array $config + * @throws FileBackendError + */ + public function __construct( array $config ) { + parent::__construct( $config ); + $this->syncChecks = isset( $config['syncChecks'] ) + ? $config['syncChecks'] + : self::CHECK_SIZE; + $this->autoResync = isset( $config['autoResync'] ) + ? $config['autoResync'] + : false; + $this->asyncWrites = isset( $config['replication'] ) && $config['replication'] === 'async'; + // Construct backends here rather than via registration + // to keep these backends hidden from outside the proxy. + $namesUsed = []; + foreach ( $config['backends'] as $index => $config ) { + $name = $config['name']; + if ( isset( $namesUsed[$name] ) ) { // don't break FileOp predicates + throw new LogicException( "Two or more backends defined with the name $name." ); + } + $namesUsed[$name] = 1; + // Alter certain sub-backend settings for sanity + unset( $config['readOnly'] ); // use proxy backend setting + unset( $config['fileJournal'] ); // use proxy backend journal + unset( $config['lockManager'] ); // lock under proxy backend + $config['domainId'] = $this->domainId; // use the proxy backend wiki ID + if ( !empty( $config['isMultiMaster'] ) ) { + if ( $this->masterIndex >= 0 ) { + throw new LogicException( 'More than one master backend defined.' ); + } + $this->masterIndex = $index; // this is the "master" + $config['fileJournal'] = $this->fileJournal; // log under proxy backend + } + if ( !empty( $config['readAffinity'] ) ) { + $this->readIndex = $index; // prefer this for reads + } + // Create sub-backend object + if ( !isset( $config['class'] ) ) { + throw new InvalidArgumentException( 'No class given for a backend config.' ); + } + $class = $config['class']; + $this->backends[$index] = new $class( $config ); + } + if ( $this->masterIndex < 0 ) { // need backends and must have a master + throw new LogicException( 'No master backend defined.' ); + } + if ( $this->readIndex < 0 ) { + $this->readIndex = $this->masterIndex; // default + } + } + + final protected function doOperationsInternal( array $ops, array $opts ) { + $status = $this->newStatus(); + + $mbe = $this->backends[$this->masterIndex]; // convenience + + // Try to lock those files for the scope of this function... + $scopeLock = null; + if ( empty( $opts['nonLocking'] ) ) { + // Try to lock those files for the scope of this function... + /** @noinspection PhpUnusedLocalVariableInspection */ + $scopeLock = $this->getScopedLocksForOps( $ops, $status ); + if ( !$status->isOK() ) { + return $status; // abort + } + } + // Clear any cache entries (after locks acquired) + $this->clearCache(); + $opts['preserveCache'] = true; // only locked files are cached + // Get the list of paths to read/write... + $relevantPaths = $this->fileStoragePathsForOps( $ops ); + // Check if the paths are valid and accessible on all backends... + $status->merge( $this->accessibilityCheck( $relevantPaths ) ); + if ( !$status->isOK() ) { + return $status; // abort + } + // Do a consistency check to see if the backends are consistent... + $syncStatus = $this->consistencyCheck( $relevantPaths ); + if ( !$syncStatus->isOK() ) { + wfDebugLog( 'FileOperation', static::class . + " failed sync check: " . FormatJson::encode( $relevantPaths ) ); + // Try to resync the clone backends to the master on the spot... + if ( $this->autoResync === false + || !$this->resyncFiles( $relevantPaths, $this->autoResync )->isOK() + ) { + $status->merge( $syncStatus ); + + return $status; // abort + } + } + // Actually attempt the operation batch on the master backend... + $realOps = $this->substOpBatchPaths( $ops, $mbe ); + $masterStatus = $mbe->doOperations( $realOps, $opts ); + $status->merge( $masterStatus ); + // Propagate the operations to the clone backends if there were no unexpected errors + // and if there were either no expected errors or if the 'force' option was used. + // However, if nothing succeeded at all, then don't replicate any of the operations. + // If $ops only had one operation, this might avoid backend sync inconsistencies. + if ( $masterStatus->isOK() && $masterStatus->successCount > 0 ) { + foreach ( $this->backends as $index => $backend ) { + if ( $index === $this->masterIndex ) { + continue; // done already + } + + $realOps = $this->substOpBatchPaths( $ops, $backend ); + if ( $this->asyncWrites && !$this->hasVolatileSources( $ops ) ) { + // Bind $scopeLock to the callback to preserve locks + DeferredUpdates::addCallableUpdate( + function () use ( $backend, $realOps, $opts, $scopeLock, $relevantPaths ) { + wfDebugLog( 'FileOperationReplication', + "'{$backend->getName()}' async replication; paths: " . + FormatJson::encode( $relevantPaths ) ); + $backend->doOperations( $realOps, $opts ); + } + ); + } else { + wfDebugLog( 'FileOperationReplication', + "'{$backend->getName()}' sync replication; paths: " . + FormatJson::encode( $relevantPaths ) ); + $status->merge( $backend->doOperations( $realOps, $opts ) ); + } + } + } + // Make 'success', 'successCount', and 'failCount' fields reflect + // the overall operation, rather than all the batches for each backend. + // Do this by only using success values from the master backend's batch. + $status->success = $masterStatus->success; + $status->successCount = $masterStatus->successCount; + $status->failCount = $masterStatus->failCount; + + return $status; + } + + /** + * Check that a set of files are consistent across all internal backends + * + * @param array $paths List of storage paths + * @return StatusValue + */ + public function consistencyCheck( array $paths ) { + $status = $this->newStatus(); + if ( $this->syncChecks == 0 || count( $this->backends ) <= 1 ) { + return $status; // skip checks + } + + // Preload all of the stat info in as few round trips as possible... + foreach ( $this->backends as $backend ) { + $realPaths = $this->substPaths( $paths, $backend ); + $backend->preloadFileStat( [ 'srcs' => $realPaths, 'latest' => true ] ); + } + + $mBackend = $this->backends[$this->masterIndex]; + foreach ( $paths as $path ) { + $params = [ 'src' => $path, 'latest' => true ]; + $mParams = $this->substOpPaths( $params, $mBackend ); + // Stat the file on the 'master' backend + $mStat = $mBackend->getFileStat( $mParams ); + if ( $this->syncChecks & self::CHECK_SHA1 ) { + $mSha1 = $mBackend->getFileSha1Base36( $mParams ); + } else { + $mSha1 = false; + } + // Check if all clone backends agree with the master... + foreach ( $this->backends as $index => $cBackend ) { + if ( $index === $this->masterIndex ) { + continue; // master + } + $cParams = $this->substOpPaths( $params, $cBackend ); + $cStat = $cBackend->getFileStat( $cParams ); + if ( $mStat ) { // file is in master + if ( !$cStat ) { // file should exist + $status->fatal( 'backend-fail-synced', $path ); + continue; + } + if ( $this->syncChecks & self::CHECK_SIZE ) { + if ( $cStat['size'] != $mStat['size'] ) { // wrong size + $status->fatal( 'backend-fail-synced', $path ); + continue; + } + } + if ( $this->syncChecks & self::CHECK_TIME ) { + $mTs = wfTimestamp( TS_UNIX, $mStat['mtime'] ); + $cTs = wfTimestamp( TS_UNIX, $cStat['mtime'] ); + if ( abs( $mTs - $cTs ) > 30 ) { // outdated file somewhere + $status->fatal( 'backend-fail-synced', $path ); + continue; + } + } + if ( $this->syncChecks & self::CHECK_SHA1 ) { + if ( $cBackend->getFileSha1Base36( $cParams ) !== $mSha1 ) { // wrong SHA1 + $status->fatal( 'backend-fail-synced', $path ); + continue; + } + } + } else { // file is not in master + if ( $cStat ) { // file should not exist + $status->fatal( 'backend-fail-synced', $path ); + } + } + } + } + + return $status; + } + + /** + * Check that a set of file paths are usable across all internal backends + * + * @param array $paths List of storage paths + * @return StatusValue + */ + public function accessibilityCheck( array $paths ) { + $status = $this->newStatus(); + if ( count( $this->backends ) <= 1 ) { + return $status; // skip checks + } + + foreach ( $paths as $path ) { + foreach ( $this->backends as $backend ) { + $realPath = $this->substPaths( $path, $backend ); + if ( !$backend->isPathUsableInternal( $realPath ) ) { + $status->fatal( 'backend-fail-usable', $path ); + } + } + } + + return $status; + } + + /** + * Check that a set of files are consistent across all internal backends + * and re-synchronize those files against the "multi master" if needed. + * + * @param array $paths List of storage paths + * @param string|bool $resyncMode False, True, or "conservative"; see __construct() + * @return StatusValue + */ + public function resyncFiles( array $paths, $resyncMode = true ) { + $status = $this->newStatus(); + + $mBackend = $this->backends[$this->masterIndex]; + foreach ( $paths as $path ) { + $mPath = $this->substPaths( $path, $mBackend ); + $mSha1 = $mBackend->getFileSha1Base36( [ 'src' => $mPath, 'latest' => true ] ); + $mStat = $mBackend->getFileStat( [ 'src' => $mPath, 'latest' => true ] ); + if ( $mStat === null || ( $mSha1 !== false && !$mStat ) ) { // sanity + $status->fatal( 'backend-fail-internal', $this->name ); + wfDebugLog( 'FileOperation', __METHOD__ + . ': File is not available on the master backend' ); + continue; // file is not available on the master backend... + } + // Check of all clone backends agree with the master... + foreach ( $this->backends as $index => $cBackend ) { + if ( $index === $this->masterIndex ) { + continue; // master + } + $cPath = $this->substPaths( $path, $cBackend ); + $cSha1 = $cBackend->getFileSha1Base36( [ 'src' => $cPath, 'latest' => true ] ); + $cStat = $cBackend->getFileStat( [ 'src' => $cPath, 'latest' => true ] ); + if ( $cStat === null || ( $cSha1 !== false && !$cStat ) ) { // sanity + $status->fatal( 'backend-fail-internal', $cBackend->getName() ); + wfDebugLog( 'FileOperation', __METHOD__ . + ': File is not available on the clone backend' ); + continue; // file is not available on the clone backend... + } + if ( $mSha1 === $cSha1 ) { + // already synced; nothing to do + } elseif ( $mSha1 !== false ) { // file is in master + if ( $resyncMode === 'conservative' + && $cStat && $cStat['mtime'] > $mStat['mtime'] + ) { + $status->fatal( 'backend-fail-synced', $path ); + continue; // don't rollback data + } + $fsFile = $mBackend->getLocalReference( + [ 'src' => $mPath, 'latest' => true ] ); + $status->merge( $cBackend->quickStore( + [ 'src' => $fsFile->getPath(), 'dst' => $cPath ] + ) ); + } elseif ( $mStat === false ) { // file is not in master + if ( $resyncMode === 'conservative' ) { + $status->fatal( 'backend-fail-synced', $path ); + continue; // don't delete data + } + $status->merge( $cBackend->quickDelete( [ 'src' => $cPath ] ) ); + } + } + } + + if ( !$status->isOK() ) { + wfDebugLog( 'FileOperation', static::class . + " failed to resync: " . FormatJson::encode( $paths ) ); + } + + return $status; + } + + /** + * Get a list of file storage paths to read or write for a list of operations + * + * @param array $ops Same format as doOperations() + * @return array List of storage paths to files (does not include directories) + */ + protected function fileStoragePathsForOps( array $ops ) { + $paths = []; + foreach ( $ops as $op ) { + if ( isset( $op['src'] ) ) { + // For things like copy/move/delete with "ignoreMissingSource" and there + // is no source file, nothing should happen and there should be no errors. + if ( empty( $op['ignoreMissingSource'] ) + || $this->fileExists( [ 'src' => $op['src'] ] ) + ) { + $paths[] = $op['src']; + } + } + if ( isset( $op['srcs'] ) ) { + $paths = array_merge( $paths, $op['srcs'] ); + } + if ( isset( $op['dst'] ) ) { + $paths[] = $op['dst']; + } + } + + return array_values( array_unique( array_filter( $paths, 'FileBackend::isStoragePath' ) ) ); + } + + /** + * Substitute the backend name in storage path parameters + * for a set of operations with that of a given internal backend. + * + * @param array $ops List of file operation arrays + * @param FileBackendStore $backend + * @return array + */ + protected function substOpBatchPaths( array $ops, FileBackendStore $backend ) { + $newOps = []; // operations + foreach ( $ops as $op ) { + $newOp = $op; // operation + foreach ( [ 'src', 'srcs', 'dst', 'dir' ] as $par ) { + if ( isset( $newOp[$par] ) ) { // string or array + $newOp[$par] = $this->substPaths( $newOp[$par], $backend ); + } + } + $newOps[] = $newOp; + } + + return $newOps; + } + + /** + * Same as substOpBatchPaths() but for a single operation + * + * @param array $ops File operation array + * @param FileBackendStore $backend + * @return array + */ + protected function substOpPaths( array $ops, FileBackendStore $backend ) { + $newOps = $this->substOpBatchPaths( [ $ops ], $backend ); + + return $newOps[0]; + } + + /** + * Substitute the backend of storage paths with an internal backend's name + * + * @param array|string $paths List of paths or single string path + * @param FileBackendStore $backend + * @return array|string + */ + protected function substPaths( $paths, FileBackendStore $backend ) { + return preg_replace( + '!^mwstore://' . preg_quote( $this->name, '!' ) . '/!', + StringUtils::escapeRegexReplacement( "mwstore://{$backend->getName()}/" ), + $paths // string or array + ); + } + + /** + * Substitute the backend of internal storage paths with the proxy backend's name + * + * @param array|string $paths List of paths or single string path + * @return array|string + */ + protected function unsubstPaths( $paths ) { + return preg_replace( + '!^mwstore://([^/]+)!', + StringUtils::escapeRegexReplacement( "mwstore://{$this->name}" ), + $paths // string or array + ); + } + + /** + * @param array $ops File operations for FileBackend::doOperations() + * @return bool Whether there are file path sources with outside lifetime/ownership + */ + protected function hasVolatileSources( array $ops ) { + foreach ( $ops as $op ) { + if ( $op['op'] === 'store' && !isset( $op['srcRef'] ) ) { + return true; // source file might be deleted anytime after do*Operations() + } + } + + return false; + } + + protected function doQuickOperationsInternal( array $ops ) { + $status = $this->newStatus(); + // Do the operations on the master backend; setting StatusValue fields... + $realOps = $this->substOpBatchPaths( $ops, $this->backends[$this->masterIndex] ); + $masterStatus = $this->backends[$this->masterIndex]->doQuickOperations( $realOps ); + $status->merge( $masterStatus ); + // Propagate the operations to the clone backends... + foreach ( $this->backends as $index => $backend ) { + if ( $index === $this->masterIndex ) { + continue; // done already + } + + $realOps = $this->substOpBatchPaths( $ops, $backend ); + if ( $this->asyncWrites && !$this->hasVolatileSources( $ops ) ) { + DeferredUpdates::addCallableUpdate( + function () use ( $backend, $realOps ) { + $backend->doQuickOperations( $realOps ); + } + ); + } else { + $status->merge( $backend->doQuickOperations( $realOps ) ); + } + } + // Make 'success', 'successCount', and 'failCount' fields reflect + // the overall operation, rather than all the batches for each backend. + // Do this by only using success values from the master backend's batch. + $status->success = $masterStatus->success; + $status->successCount = $masterStatus->successCount; + $status->failCount = $masterStatus->failCount; + + return $status; + } + + protected function doPrepare( array $params ) { + return $this->doDirectoryOp( 'prepare', $params ); + } + + protected function doSecure( array $params ) { + return $this->doDirectoryOp( 'secure', $params ); + } + + protected function doPublish( array $params ) { + return $this->doDirectoryOp( 'publish', $params ); + } + + protected function doClean( array $params ) { + return $this->doDirectoryOp( 'clean', $params ); + } + + /** + * @param string $method One of (doPrepare,doSecure,doPublish,doClean) + * @param array $params Method arguments + * @return StatusValue + */ + protected function doDirectoryOp( $method, array $params ) { + $status = $this->newStatus(); + + $realParams = $this->substOpPaths( $params, $this->backends[$this->masterIndex] ); + $masterStatus = $this->backends[$this->masterIndex]->$method( $realParams ); + $status->merge( $masterStatus ); + + foreach ( $this->backends as $index => $backend ) { + if ( $index === $this->masterIndex ) { + continue; // already done + } + + $realParams = $this->substOpPaths( $params, $backend ); + if ( $this->asyncWrites ) { + DeferredUpdates::addCallableUpdate( + function () use ( $backend, $method, $realParams ) { + $backend->$method( $realParams ); + } + ); + } else { + $status->merge( $backend->$method( $realParams ) ); + } + } + + return $status; + } + + public function concatenate( array $params ) { + $status = $this->newStatus(); + // We are writing to an FS file, so we don't need to do this per-backend + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + $status->merge( $this->backends[$index]->concatenate( $realParams ) ); + + return $status; + } + + public function fileExists( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->fileExists( $realParams ); + } + + public function getFileTimestamp( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileTimestamp( $realParams ); + } + + public function getFileSize( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileSize( $realParams ); + } + + public function getFileStat( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileStat( $realParams ); + } + + public function getFileXAttributes( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileXAttributes( $realParams ); + } + + public function getFileContentsMulti( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + $contentsM = $this->backends[$index]->getFileContentsMulti( $realParams ); + + $contents = []; // (path => FSFile) mapping using the proxy backend's name + foreach ( $contentsM as $path => $data ) { + $contents[$this->unsubstPaths( $path )] = $data; + } + + return $contents; + } + + public function getFileSha1Base36( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileSha1Base36( $realParams ); + } + + public function getFileProps( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileProps( $realParams ); + } + + public function streamFile( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->streamFile( $realParams ); + } + + public function getLocalReferenceMulti( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + $fsFilesM = $this->backends[$index]->getLocalReferenceMulti( $realParams ); + + $fsFiles = []; // (path => FSFile) mapping using the proxy backend's name + foreach ( $fsFilesM as $path => $fsFile ) { + $fsFiles[$this->unsubstPaths( $path )] = $fsFile; + } + + return $fsFiles; + } + + public function getLocalCopyMulti( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + $tempFilesM = $this->backends[$index]->getLocalCopyMulti( $realParams ); + + $tempFiles = []; // (path => TempFSFile) mapping using the proxy backend's name + foreach ( $tempFilesM as $path => $tempFile ) { + $tempFiles[$this->unsubstPaths( $path )] = $tempFile; + } + + return $tempFiles; + } + + public function getFileHttpUrl( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->getFileHttpUrl( $realParams ); + } + + public function directoryExists( array $params ) { + $realParams = $this->substOpPaths( $params, $this->backends[$this->masterIndex] ); + + return $this->backends[$this->masterIndex]->directoryExists( $realParams ); + } + + public function getDirectoryList( array $params ) { + $realParams = $this->substOpPaths( $params, $this->backends[$this->masterIndex] ); + + return $this->backends[$this->masterIndex]->getDirectoryList( $realParams ); + } + + public function getFileList( array $params ) { + $realParams = $this->substOpPaths( $params, $this->backends[$this->masterIndex] ); + + return $this->backends[$this->masterIndex]->getFileList( $realParams ); + } + + public function getFeatures() { + return $this->backends[$this->masterIndex]->getFeatures(); + } + + public function clearCache( array $paths = null ) { + foreach ( $this->backends as $backend ) { + $realPaths = is_array( $paths ) ? $this->substPaths( $paths, $backend ) : null; + $backend->clearCache( $realPaths ); + } + } + + public function preloadCache( array $paths ) { + $realPaths = $this->substPaths( $paths, $this->backends[$this->readIndex] ); + $this->backends[$this->readIndex]->preloadCache( $realPaths ); + } + + public function preloadFileStat( array $params ) { + $index = $this->getReadIndexFromParams( $params ); + $realParams = $this->substOpPaths( $params, $this->backends[$index] ); + + return $this->backends[$index]->preloadFileStat( $realParams ); + } + + public function getScopedLocksForOps( array $ops, StatusValue $status ) { + $realOps = $this->substOpBatchPaths( $ops, $this->backends[$this->masterIndex] ); + $fileOps = $this->backends[$this->masterIndex]->getOperationsInternal( $realOps ); + // Get the paths to lock from the master backend + $paths = $this->backends[$this->masterIndex]->getPathsToLockForOpsInternal( $fileOps ); + // Get the paths under the proxy backend's name + $pbPaths = [ + LockManager::LOCK_UW => $this->unsubstPaths( $paths[LockManager::LOCK_UW] ), + LockManager::LOCK_EX => $this->unsubstPaths( $paths[LockManager::LOCK_EX] ) + ]; + + // Actually acquire the locks + return $this->getScopedFileLocks( $pbPaths, 'mixed', $status ); + } + + /** + * @param array $params + * @return int The master or read affinity backend index, based on $params['latest'] + */ + protected function getReadIndexFromParams( array $params ) { + return !empty( $params['latest'] ) ? $this->masterIndex : $this->readIndex; + } +} |