includes/libs/filebackend/FileBackendMultiWrite.php
<?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
*/
use MediaWiki\Deferred\DeferredUpdates;
use Wikimedia\Timestamp\ConvertibleTimestamp;
/**
* @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.
* Except on getting list of thumbnails for write operations.
* 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;
/** @var int Compare file sizes among backends */
private const CHECK_SIZE = 1;
/** @var int Compare file mtimes among backends */
private const CHECK_TIME = 2;
/** @var int Compare file hashes among backends */
private const CHECK_SHA1 = 4;
/**
* Construct a proxy backend that consists of several internal backends.
* Locking 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.
*
* @param array $config
* @throws LogicException
*/
public function __construct( array $config ) {
parent::__construct( $config );
$this->syncChecks = $config['syncChecks'] ?? self::CHECK_SIZE;
$this->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 => $beConfig ) {
$name = $beConfig['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
unset( $beConfig['readOnly'] ); // use proxy backend setting
unset( $beConfig['lockManager'] ); // lock under proxy backend
$beConfig['domainId'] = $this->domainId; // use the proxy backend wiki ID
$beConfig['logger'] = $this->logger; // use the proxy backend logger
if ( !empty( $beConfig['isMultiMaster'] ) ) {
if ( $this->masterIndex >= 0 ) {
throw new LogicException( 'More than one master backend defined.' );
}
$this->masterIndex = $index; // this is the "master"
}
if ( !empty( $beConfig['readAffinity'] ) ) {
$this->readIndex = $index; // prefer this for reads
}
// Create sub-backend object
if ( !isset( $beConfig['class'] ) ) {
throw new InvalidArgumentException( 'No class given for a backend config.' );
}
$class = $beConfig['class'];
$this->backends[$index] = new $class( $beConfig );
}
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();
$fname = __METHOD__;
$mbe = $this->backends[$this->masterIndex]; // convenience
// Acquire any locks as needed
$scopeLock = null;
if ( empty( $opts['nonLocking'] ) ) {
$scopeLock = $this->getScopedLocksForOps( $ops, $status );
if ( !$status->isOK() ) {
return $status; // abort
}
}
// Get the list of paths to read/write
$relevantPaths = $this->fileStoragePathsForOps( $ops );
// Clear any cache entries (after locks acquired)
$this->clearCache( $relevantPaths );
$opts['preserveCache'] = true; // only locked files are cached
// 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() ) {
$this->logger->error(
"$fname: 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 everything didn't fail due to predicted errors. 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, $fname
) {
$this->logger->debug(
"$fname: '{$backend->getName()}' async replication; paths: " .
FormatJson::encode( $relevantPaths )
);
$backend->doOperations( $realOps, $opts );
}
);
} else {
$this->logger->debug(
"$fname: '{$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
*
* This method should only be called if the files are locked or the backend
* is in read-only mode
*
* @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 ] );
}
foreach ( $paths as $path ) {
$params = [ 'src' => $path, 'latest' => true ];
// Get the state of the file on the master backend
$masterBackend = $this->backends[$this->masterIndex];
$masterParams = $this->substOpPaths( $params, $masterBackend );
$masterStat = $masterBackend->getFileStat( $masterParams );
if ( $masterStat === self::STAT_ERROR ) {
$status->fatal( 'backend-fail-stat', $path );
continue;
}
if ( $this->syncChecks & self::CHECK_SHA1 ) {
$masterSha1 = $masterBackend->getFileSha1Base36( $masterParams );
if ( ( $masterSha1 !== false ) !== (bool)$masterStat ) {
$status->fatal( 'backend-fail-hash', $path );
continue;
}
} else {
$masterSha1 = null; // unused
}
// Check if all clone backends agree with the master...
foreach ( $this->backends as $index => $cloneBackend ) {
if ( $index === $this->masterIndex ) {
continue; // master
}
// Get the state of the file on the clone backend
$cloneParams = $this->substOpPaths( $params, $cloneBackend );
$cloneStat = $cloneBackend->getFileStat( $cloneParams );
if ( $masterStat ) {
// File exists in the master backend
if ( !$cloneStat ) {
// File is missing from the clone backend
$status->fatal( 'backend-fail-synced', $path );
} elseif (
( $this->syncChecks & self::CHECK_SIZE ) &&
$cloneStat['size'] !== $masterStat['size']
) {
// File in the clone backend is different
$status->fatal( 'backend-fail-synced', $path );
} elseif (
( $this->syncChecks & self::CHECK_TIME ) &&
abs(
(int)ConvertibleTimestamp::convert( TS_UNIX, $masterStat['mtime'] ) -
(int)ConvertibleTimestamp::convert( TS_UNIX, $cloneStat['mtime'] )
) > 30
) {
// File in the clone backend is significantly newer or older
$status->fatal( 'backend-fail-synced', $path );
} elseif (
( $this->syncChecks & self::CHECK_SHA1 ) &&
$cloneBackend->getFileSha1Base36( $cloneParams ) !== $masterSha1
) {
// File in the clone backend is different
$status->fatal( 'backend-fail-synced', $path );
}
} else {
// File does not exist in the master backend
if ( $cloneStat ) {
// Stray file exists in the clone backend
$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.
*
* This method should only be called if the files are locked
*
* @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();
$fname = __METHOD__;
foreach ( $paths as $path ) {
$params = [ 'src' => $path, 'latest' => true ];
// Get the state of the file on the master backend
$masterBackend = $this->backends[$this->masterIndex];
$masterParams = $this->substOpPaths( $params, $masterBackend );
$masterPath = $masterParams['src'];
$masterStat = $masterBackend->getFileStat( $masterParams );
if ( $masterStat === self::STAT_ERROR ) {
$status->fatal( 'backend-fail-stat', $path );
$this->logger->error( "$fname: file '$masterPath' is not available" );
continue;
}
$masterSha1 = $masterBackend->getFileSha1Base36( $masterParams );
if ( ( $masterSha1 !== false ) !== (bool)$masterStat ) {
$status->fatal( 'backend-fail-hash', $path );
$this->logger->error( "$fname: file '$masterPath' hash does not match stat" );
continue;
}
// Check of all clone backends agree with the master...
foreach ( $this->backends as $index => $cloneBackend ) {
if ( $index === $this->masterIndex ) {
continue; // master
}
// Get the state of the file on the clone backend
$cloneParams = $this->substOpPaths( $params, $cloneBackend );
$clonePath = $cloneParams['src'];
$cloneStat = $cloneBackend->getFileStat( $cloneParams );
if ( $cloneStat === self::STAT_ERROR ) {
$status->fatal( 'backend-fail-stat', $path );
$this->logger->error( "$fname: file '$clonePath' is not available" );
continue;
}
$cloneSha1 = $cloneBackend->getFileSha1Base36( $cloneParams );
if ( ( $cloneSha1 !== false ) !== (bool)$cloneStat ) {
$status->fatal( 'backend-fail-hash', $path );
$this->logger->error( "$fname: file '$clonePath' hash does not match stat" );
continue;
}
if ( $masterSha1 === $cloneSha1 ) {
// File is either the same in both backends or absent from both backends
$this->logger->debug( "$fname: file '$clonePath' matches '$masterPath'" );
} elseif ( $masterSha1 !== false ) {
// File is either missing from or different in the clone backend
if (
$resyncMode === 'conservative' &&
$cloneStat &&
// @phan-suppress-next-line PhanTypeArraySuspiciousNullable
$cloneStat['mtime'] > $masterStat['mtime']
) {
// Do not replace files with older ones; reduces the risk of data loss
$status->fatal( 'backend-fail-synced', $path );
} else {
// Copy the master backend file to the clone backend in overwrite mode
$fsFile = $masterBackend->getLocalReference( $masterParams );
$status->merge( $cloneBackend->quickStore( [
'src' => $fsFile,
'dst' => $clonePath
] ) );
}
} elseif ( $masterStat === false ) {
// Stray file exists in the clone backend
if ( $resyncMode === 'conservative' ) {
// Do not delete stray files; reduces the risk of data loss
$status->fatal( 'backend-fail-synced', $path );
$this->logger->error( "$fname: not allowed to delete file '$clonePath'" );
} else {
// Delete the stay file from the clone backend
$status->merge( $cloneBackend->quickDelete( [ 'src' => $clonePath ] ) );
}
}
}
}
if ( !$status->isOK() ) {
$this->logger->error( "$fname: 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::class, '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 string[]|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
* @param FileBackendStore $backend internal storage backend
* @return string[]|string
*/
protected function unsubstPaths( $paths, FileBackendStore $backend ) {
return preg_replace(
'!^mwstore://' . preg_quote( $backend->getName(), '!' ) . '/!',
StringUtils::escapeRegexReplacement( "mwstore://{$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, array $opts ) {
$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(
static 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(
static 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, $this->backends[$index] )] = $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, $this->backends[$index] )] = $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, $this->backends[$index] )] = $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 ) {
if ( isset( $params['forWrite'] ) && $params['forWrite'] ) {
return $this->getFileListForWrite( $params );
}
$realParams = $this->substOpPaths( $params, $this->backends[$this->masterIndex] );
return $this->backends[$this->masterIndex]->getFileList( $realParams );
}
private function getFileListForWrite( $params ) {
$files = [];
// Get the list of thumbnails from all backends to allow
// deleting all of them. Otherwise, old thumbnails existing on
// one backend only won't get updated in reupload (T331138).
foreach ( $this->backends as $backend ) {
$realParams = $this->substOpPaths( $params, $backend );
$iterator = $backend->getFileList( $realParams );
if ( $iterator !== null ) {
foreach ( $iterator as $file ) {
$files[] = $file;
}
}
}
return array_unique( $files );
}
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],
$this->backends[$this->masterIndex]
),
LockManager::LOCK_EX => $this->unsubstPaths(
$paths[LockManager::LOCK_EX],
$this->backends[$this->masterIndex]
)
];
// 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;
}
}