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mediawiki_ynh/sources/mediawiki/includes/filebackend/FileBackendStore.php

1738 lines
60 KiB
PHP

<?php
/**
* Base class for all backends using particular storage medium.
*
* 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
* @author Aaron Schulz
*/
/**
* @brief Base class for all backends using particular storage medium.
*
* This class defines the methods as abstract that subclasses must implement.
* Outside callers should *not* use functions with "Internal" in the name.
*
* The FileBackend operations are implemented using basic functions
* such as storeInternal(), copyInternal(), deleteInternal() and the like.
* This class is also responsible for path resolution and sanitization.
*
* @ingroup FileBackend
* @since 1.19
*/
abstract class FileBackendStore extends FileBackend {
/** @var BagOStuff */
protected $memCache;
/** @var ProcessCacheLRU Map of paths to small (RAM/disk) cache items */
protected $cheapCache;
/** @var ProcessCacheLRU Map of paths to large (RAM/disk) cache items */
protected $expensiveCache;
/** @var Array Map of container names to sharding config */
protected $shardViaHashLevels = array();
/** @var callback Method to get the MIME type of files */
protected $mimeCallback;
protected $maxFileSize = 4294967296; // integer bytes (4GiB)
const CACHE_TTL = 10; // integer; TTL in seconds for process cache entries
const CACHE_CHEAP_SIZE = 300; // integer; max entries in "cheap cache"
const CACHE_EXPENSIVE_SIZE = 5; // integer; max entries in "expensive cache"
/**
* @see FileBackend::__construct()
* Additional $config params include:
* - mimeCallback : Callback that takes (storage path, content, file system path) and
* returns the MIME type of the file or 'unknown/unknown'. The file
* system path parameter should be used if the content one is null.
*
* @param array $config
*/
public function __construct( array $config ) {
parent::__construct( $config );
$this->mimeCallback = isset( $config['mimeCallback'] )
? $config['mimeCallback']
: function( $storagePath, $content, $fsPath ) {
// @TODO: handle the case of extension-less files using the contents
return StreamFile::contentTypeFromPath( $storagePath ) ?: 'unknown/unknown';
};
$this->memCache = new EmptyBagOStuff(); // disabled by default
$this->cheapCache = new ProcessCacheLRU( self::CACHE_CHEAP_SIZE );
$this->expensiveCache = new ProcessCacheLRU( self::CACHE_EXPENSIVE_SIZE );
}
/**
* Get the maximum allowable file size given backend
* medium restrictions and basic performance constraints.
* Do not call this function from places outside FileBackend and FileOp.
*
* @return integer Bytes
*/
final public function maxFileSizeInternal() {
return $this->maxFileSize;
}
/**
* Check if a file can be created or changed at a given storage path.
* FS backends should check if the parent directory exists, files can be
* written under it, and that any file already there is writable.
* Backends using key/value stores should check if the container exists.
*
* @param string $storagePath
* @return bool
*/
abstract public function isPathUsableInternal( $storagePath );
/**
* Create a file in the backend with the given contents.
* This will overwrite any file that exists at the destination.
* Do not call this function from places outside FileBackend and FileOp.
*
* $params include:
* - content : the raw file contents
* - dst : destination storage path
* - headers : HTTP header name/value map
* - async : Status will be returned immediately if supported.
* If the status is OK, then its value field will be
* set to a FileBackendStoreOpHandle object.
* - dstExists : Whether a file exists at the destination (optimization).
* Callers can use "false" if no existing file is being changed.
*
* @param array $params
* @return Status
*/
final public function createInternal( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
if ( strlen( $params['content'] ) > $this->maxFileSizeInternal() ) {
$status = Status::newFatal( 'backend-fail-maxsize',
$params['dst'], $this->maxFileSizeInternal() );
} else {
$status = $this->doCreateInternal( $params );
$this->clearCache( array( $params['dst'] ) );
if ( !isset( $params['dstExists'] ) || $params['dstExists'] ) {
$this->deleteFileCache( $params['dst'] ); // persistent cache
}
}
return $status;
}
/**
* @see FileBackendStore::createInternal()
* @return Status
*/
abstract protected function doCreateInternal( array $params );
/**
* Store a file into the backend from a file on disk.
* This will overwrite any file that exists at the destination.
* Do not call this function from places outside FileBackend and FileOp.
*
* $params include:
* - src : source path on disk
* - dst : destination storage path
* - headers : HTTP header name/value map
* - async : Status will be returned immediately if supported.
* If the status is OK, then its value field will be
* set to a FileBackendStoreOpHandle object.
* - dstExists : Whether a file exists at the destination (optimization).
* Callers can use "false" if no existing file is being changed.
*
* @param array $params
* @return Status
*/
final public function storeInternal( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
if ( filesize( $params['src'] ) > $this->maxFileSizeInternal() ) {
$status = Status::newFatal( 'backend-fail-maxsize',
$params['dst'], $this->maxFileSizeInternal() );
} else {
$status = $this->doStoreInternal( $params );
$this->clearCache( array( $params['dst'] ) );
if ( !isset( $params['dstExists'] ) || $params['dstExists'] ) {
$this->deleteFileCache( $params['dst'] ); // persistent cache
}
}
return $status;
}
/**
* @see FileBackendStore::storeInternal()
* @return Status
*/
abstract protected function doStoreInternal( array $params );
/**
* Copy a file from one storage path to another in the backend.
* This will overwrite any file that exists at the destination.
* Do not call this function from places outside FileBackend and FileOp.
*
* $params include:
* - src : source storage path
* - dst : destination storage path
* - ignoreMissingSource : do nothing if the source file does not exist
* - headers : HTTP header name/value map
* - async : Status will be returned immediately if supported.
* If the status is OK, then its value field will be
* set to a FileBackendStoreOpHandle object.
* - dstExists : Whether a file exists at the destination (optimization).
* Callers can use "false" if no existing file is being changed.
*
* @param array $params
* @return Status
*/
final public function copyInternal( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = $this->doCopyInternal( $params );
$this->clearCache( array( $params['dst'] ) );
if ( !isset( $params['dstExists'] ) || $params['dstExists'] ) {
$this->deleteFileCache( $params['dst'] ); // persistent cache
}
return $status;
}
/**
* @see FileBackendStore::copyInternal()
* @return Status
*/
abstract protected function doCopyInternal( array $params );
/**
* Delete a file at the storage path.
* Do not call this function from places outside FileBackend and FileOp.
*
* $params include:
* - src : source storage path
* - ignoreMissingSource : do nothing if the source file does not exist
* - async : Status will be returned immediately if supported.
* If the status is OK, then its value field will be
* set to a FileBackendStoreOpHandle object.
*
* @param array $params
* @return Status
*/
final public function deleteInternal( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = $this->doDeleteInternal( $params );
$this->clearCache( array( $params['src'] ) );
$this->deleteFileCache( $params['src'] ); // persistent cache
return $status;
}
/**
* @see FileBackendStore::deleteInternal()
* @return Status
*/
abstract protected function doDeleteInternal( array $params );
/**
* Move a file from one storage path to another in the backend.
* This will overwrite any file that exists at the destination.
* Do not call this function from places outside FileBackend and FileOp.
*
* $params include:
* - src : source storage path
* - dst : destination storage path
* - ignoreMissingSource : do nothing if the source file does not exist
* - headers : HTTP header name/value map
* - async : Status will be returned immediately if supported.
* If the status is OK, then its value field will be
* set to a FileBackendStoreOpHandle object.
* - dstExists : Whether a file exists at the destination (optimization).
* Callers can use "false" if no existing file is being changed.
*
* @param array $params
* @return Status
*/
final public function moveInternal( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = $this->doMoveInternal( $params );
$this->clearCache( array( $params['src'], $params['dst'] ) );
$this->deleteFileCache( $params['src'] ); // persistent cache
if ( !isset( $params['dstExists'] ) || $params['dstExists'] ) {
$this->deleteFileCache( $params['dst'] ); // persistent cache
}
return $status;
}
/**
* @see FileBackendStore::moveInternal()
* @return Status
*/
protected function doMoveInternal( array $params ) {
unset( $params['async'] ); // two steps, won't work here :)
$nsrc = FileBackend::normalizeStoragePath( $params['src'] );
$ndst = FileBackend::normalizeStoragePath( $params['dst'] );
// Copy source to dest
$status = $this->copyInternal( $params );
if ( $nsrc !== $ndst && $status->isOK() ) {
// Delete source (only fails due to races or network problems)
$status->merge( $this->deleteInternal( array( 'src' => $params['src'] ) ) );
$status->setResult( true, $status->value ); // ignore delete() errors
}
return $status;
}
/**
* Alter metadata for a file at the storage path.
* Do not call this function from places outside FileBackend and FileOp.
*
* $params include:
* - src : source storage path
* - headers : HTTP header name/value map
* - async : Status will be returned immediately if supported.
* If the status is OK, then its value field will be
* set to a FileBackendStoreOpHandle object.
*
* @param array $params
* @return Status
*/
final public function describeInternal( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
if ( count( $params['headers'] ) ) {
$status = $this->doDescribeInternal( $params );
$this->clearCache( array( $params['src'] ) );
$this->deleteFileCache( $params['src'] ); // persistent cache
} else {
$status = Status::newGood(); // nothing to do
}
return $status;
}
/**
* @see FileBackendStore::describeInternal()
* @return Status
*/
protected function doDescribeInternal( array $params ) {
return Status::newGood();
}
/**
* No-op file operation that does nothing.
* Do not call this function from places outside FileBackend and FileOp.
*
* @param array $params
* @return Status
*/
final public function nullInternal( array $params ) {
return Status::newGood();
}
final public function concatenate( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
// Try to lock the source files for the scope of this function
$scopeLockS = $this->getScopedFileLocks( $params['srcs'], LockManager::LOCK_UW, $status );
if ( $status->isOK() ) {
// Actually do the file concatenation...
$start_time = microtime( true );
$status->merge( $this->doConcatenate( $params ) );
$sec = microtime( true ) - $start_time;
if ( !$status->isOK() ) {
wfDebugLog( 'FileOperation', get_class( $this ) . " failed to concatenate " .
count( $params['srcs'] ) . " file(s) [$sec sec]" );
}
}
return $status;
}
/**
* @see FileBackendStore::concatenate()
* @return Status
*/
protected function doConcatenate( array $params ) {
$status = Status::newGood();
$tmpPath = $params['dst']; // convenience
unset( $params['latest'] ); // sanity
// Check that the specified temp file is valid...
wfSuppressWarnings();
$ok = ( is_file( $tmpPath ) && filesize( $tmpPath ) == 0 );
wfRestoreWarnings();
if ( !$ok ) { // not present or not empty
$status->fatal( 'backend-fail-opentemp', $tmpPath );
return $status;
}
// Get local FS versions of the chunks needed for the concatenation...
$fsFiles = $this->getLocalReferenceMulti( $params );
foreach ( $fsFiles as $path => &$fsFile ) {
if ( !$fsFile ) { // chunk failed to download?
$fsFile = $this->getLocalReference( array( 'src' => $path ) );
if ( !$fsFile ) { // retry failed?
$status->fatal( 'backend-fail-read', $path );
return $status;
}
}
}
unset( $fsFile ); // unset reference so we can reuse $fsFile
// Get a handle for the destination temp file
$tmpHandle = fopen( $tmpPath, 'ab' );
if ( $tmpHandle === false ) {
$status->fatal( 'backend-fail-opentemp', $tmpPath );
return $status;
}
// Build up the temp file using the source chunks (in order)...
foreach ( $fsFiles as $virtualSource => $fsFile ) {
// Get a handle to the local FS version
$sourceHandle = fopen( $fsFile->getPath(), 'rb' );
if ( $sourceHandle === false ) {
fclose( $tmpHandle );
$status->fatal( 'backend-fail-read', $virtualSource );
return $status;
}
// Append chunk to file (pass chunk size to avoid magic quotes)
if ( !stream_copy_to_stream( $sourceHandle, $tmpHandle ) ) {
fclose( $sourceHandle );
fclose( $tmpHandle );
$status->fatal( 'backend-fail-writetemp', $tmpPath );
return $status;
}
fclose( $sourceHandle );
}
if ( !fclose( $tmpHandle ) ) {
$status->fatal( 'backend-fail-closetemp', $tmpPath );
return $status;
}
clearstatcache(); // temp file changed
return $status;
}
final protected function doPrepare( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dir'] );
return $status; // invalid storage path
}
if ( $shard !== null ) { // confined to a single container/shard
$status->merge( $this->doPrepareInternal( $fullCont, $dir, $params ) );
} else { // directory is on several shards
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
foreach ( $this->getContainerSuffixes( $shortCont ) as $suffix ) {
$status->merge( $this->doPrepareInternal( "{$fullCont}{$suffix}", $dir, $params ) );
}
}
return $status;
}
/**
* @see FileBackendStore::doPrepare()
* @return Status
*/
protected function doPrepareInternal( $container, $dir, array $params ) {
return Status::newGood();
}
final protected function doSecure( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dir'] );
return $status; // invalid storage path
}
if ( $shard !== null ) { // confined to a single container/shard
$status->merge( $this->doSecureInternal( $fullCont, $dir, $params ) );
} else { // directory is on several shards
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
foreach ( $this->getContainerSuffixes( $shortCont ) as $suffix ) {
$status->merge( $this->doSecureInternal( "{$fullCont}{$suffix}", $dir, $params ) );
}
}
return $status;
}
/**
* @see FileBackendStore::doSecure()
* @return Status
*/
protected function doSecureInternal( $container, $dir, array $params ) {
return Status::newGood();
}
final protected function doPublish( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dir'] );
return $status; // invalid storage path
}
if ( $shard !== null ) { // confined to a single container/shard
$status->merge( $this->doPublishInternal( $fullCont, $dir, $params ) );
} else { // directory is on several shards
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
foreach ( $this->getContainerSuffixes( $shortCont ) as $suffix ) {
$status->merge( $this->doPublishInternal( "{$fullCont}{$suffix}", $dir, $params ) );
}
}
return $status;
}
/**
* @see FileBackendStore::doPublish()
* @return Status
*/
protected function doPublishInternal( $container, $dir, array $params ) {
return Status::newGood();
}
final protected function doClean( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
// Recursive: first delete all empty subdirs recursively
if ( !empty( $params['recursive'] ) && !$this->directoriesAreVirtual() ) {
$subDirsRel = $this->getTopDirectoryList( array( 'dir' => $params['dir'] ) );
if ( $subDirsRel !== null ) { // no errors
foreach ( $subDirsRel as $subDirRel ) {
$subDir = $params['dir'] . "/{$subDirRel}"; // full path
$status->merge( $this->doClean( array( 'dir' => $subDir ) + $params ) );
}
unset( $subDirsRel ); // free directory for rmdir() on Windows (for FS backends)
}
}
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dir'] );
return $status; // invalid storage path
}
// Attempt to lock this directory...
$filesLockEx = array( $params['dir'] );
$scopedLockE = $this->getScopedFileLocks( $filesLockEx, LockManager::LOCK_EX, $status );
if ( !$status->isOK() ) {
return $status; // abort
}
if ( $shard !== null ) { // confined to a single container/shard
$status->merge( $this->doCleanInternal( $fullCont, $dir, $params ) );
$this->deleteContainerCache( $fullCont ); // purge cache
} else { // directory is on several shards
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
foreach ( $this->getContainerSuffixes( $shortCont ) as $suffix ) {
$status->merge( $this->doCleanInternal( "{$fullCont}{$suffix}", $dir, $params ) );
$this->deleteContainerCache( "{$fullCont}{$suffix}" ); // purge cache
}
}
return $status;
}
/**
* @see FileBackendStore::doClean()
* @return Status
*/
protected function doCleanInternal( $container, $dir, array $params ) {
return Status::newGood();
}
final public function fileExists( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$stat = $this->getFileStat( $params );
return ( $stat === null ) ? null : (bool)$stat; // null => failure
}
final public function getFileTimestamp( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$stat = $this->getFileStat( $params );
return $stat ? $stat['mtime'] : false;
}
final public function getFileSize( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$stat = $this->getFileStat( $params );
return $stat ? $stat['size'] : false;
}
final public function getFileStat( array $params ) {
$path = self::normalizeStoragePath( $params['src'] );
if ( $path === null ) {
return false; // invalid storage path
}
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$latest = !empty( $params['latest'] ); // use latest data?
if ( !$this->cheapCache->has( $path, 'stat', self::CACHE_TTL ) ) {
$this->primeFileCache( array( $path ) ); // check persistent cache
}
if ( $this->cheapCache->has( $path, 'stat', self::CACHE_TTL ) ) {
$stat = $this->cheapCache->get( $path, 'stat' );
// If we want the latest data, check that this cached
// value was in fact fetched with the latest available data.
if ( is_array( $stat ) ) {
if ( !$latest || $stat['latest'] ) {
return $stat;
}
} elseif ( in_array( $stat, array( 'NOT_EXIST', 'NOT_EXIST_LATEST' ) ) ) {
if ( !$latest || $stat === 'NOT_EXIST_LATEST' ) {
return false;
}
}
}
wfProfileIn( __METHOD__ . '-miss' );
wfProfileIn( __METHOD__ . '-miss-' . $this->name );
$stat = $this->doGetFileStat( $params );
wfProfileOut( __METHOD__ . '-miss-' . $this->name );
wfProfileOut( __METHOD__ . '-miss' );
if ( is_array( $stat ) ) { // file exists
$stat['latest'] = $latest;
$this->cheapCache->set( $path, 'stat', $stat );
$this->setFileCache( $path, $stat ); // update persistent cache
if ( isset( $stat['sha1'] ) ) { // some backends store SHA-1 as metadata
$this->cheapCache->set( $path, 'sha1',
array( 'hash' => $stat['sha1'], 'latest' => $latest ) );
}
} elseif ( $stat === false ) { // file does not exist
$this->cheapCache->set( $path, 'stat', $latest ? 'NOT_EXIST_LATEST' : 'NOT_EXIST' );
$this->cheapCache->set( $path, 'sha1', // the SHA-1 must be false too
array( 'hash' => false, 'latest' => $latest ) );
wfDebug( __METHOD__ . ": File $path does not exist.\n" );
} else { // an error occurred
wfDebug( __METHOD__ . ": Could not stat file $path.\n" );
}
return $stat;
}
/**
* @see FileBackendStore::getFileStat()
*/
abstract protected function doGetFileStat( array $params );
public function getFileContentsMulti( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$params = $this->setConcurrencyFlags( $params );
$contents = $this->doGetFileContentsMulti( $params );
return $contents;
}
/**
* @see FileBackendStore::getFileContentsMulti()
* @return Array
*/
protected function doGetFileContentsMulti( array $params ) {
$contents = array();
foreach ( $this->doGetLocalReferenceMulti( $params ) as $path => $fsFile ) {
wfSuppressWarnings();
$contents[$path] = $fsFile ? file_get_contents( $fsFile->getPath() ) : false;
wfRestoreWarnings();
}
return $contents;
}
final public function getFileSha1Base36( array $params ) {
$path = self::normalizeStoragePath( $params['src'] );
if ( $path === null ) {
return false; // invalid storage path
}
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$latest = !empty( $params['latest'] ); // use latest data?
if ( $this->cheapCache->has( $path, 'sha1', self::CACHE_TTL ) ) {
$stat = $this->cheapCache->get( $path, 'sha1' );
// If we want the latest data, check that this cached
// value was in fact fetched with the latest available data.
if ( !$latest || $stat['latest'] ) {
return $stat['hash'];
}
}
wfProfileIn( __METHOD__ . '-miss' );
wfProfileIn( __METHOD__ . '-miss-' . $this->name );
$hash = $this->doGetFileSha1Base36( $params );
wfProfileOut( __METHOD__ . '-miss-' . $this->name );
wfProfileOut( __METHOD__ . '-miss' );
$this->cheapCache->set( $path, 'sha1', array( 'hash' => $hash, 'latest' => $latest ) );
return $hash;
}
/**
* @see FileBackendStore::getFileSha1Base36()
* @return bool|string
*/
protected function doGetFileSha1Base36( array $params ) {
$fsFile = $this->getLocalReference( $params );
if ( !$fsFile ) {
return false;
} else {
return $fsFile->getSha1Base36();
}
}
final public function getFileProps( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$fsFile = $this->getLocalReference( $params );
$props = $fsFile ? $fsFile->getProps() : FSFile::placeholderProps();
return $props;
}
final public function getLocalReferenceMulti( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$params = $this->setConcurrencyFlags( $params );
$fsFiles = array(); // (path => FSFile)
$latest = !empty( $params['latest'] ); // use latest data?
// Reuse any files already in process cache...
foreach ( $params['srcs'] as $src ) {
$path = self::normalizeStoragePath( $src );
if ( $path === null ) {
$fsFiles[$src] = null; // invalid storage path
} elseif ( $this->expensiveCache->has( $path, 'localRef' ) ) {
$val = $this->expensiveCache->get( $path, 'localRef' );
// If we want the latest data, check that this cached
// value was in fact fetched with the latest available data.
if ( !$latest || $val['latest'] ) {
$fsFiles[$src] = $val['object'];
}
}
}
// Fetch local references of any remaning files...
$params['srcs'] = array_diff( $params['srcs'], array_keys( $fsFiles ) );
foreach ( $this->doGetLocalReferenceMulti( $params ) as $path => $fsFile ) {
$fsFiles[$path] = $fsFile;
if ( $fsFile ) { // update the process cache...
$this->expensiveCache->set( $path, 'localRef',
array( 'object' => $fsFile, 'latest' => $latest ) );
}
}
return $fsFiles;
}
/**
* @see FileBackendStore::getLocalReferenceMulti()
* @return Array
*/
protected function doGetLocalReferenceMulti( array $params ) {
return $this->doGetLocalCopyMulti( $params );
}
final public function getLocalCopyMulti( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$params = $this->setConcurrencyFlags( $params );
$tmpFiles = $this->doGetLocalCopyMulti( $params );
return $tmpFiles;
}
/**
* @see FileBackendStore::getLocalCopyMulti()
* @return Array
*/
abstract protected function doGetLocalCopyMulti( array $params );
/**
* @see FileBackend::getFileHttpUrl()
* @return string|null
*/
public function getFileHttpUrl( array $params ) {
return null; // not supported
}
final public function streamFile( array $params ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
$info = $this->getFileStat( $params );
if ( !$info ) { // let StreamFile handle the 404
$status->fatal( 'backend-fail-notexists', $params['src'] );
}
// Set output buffer and HTTP headers for stream
$extraHeaders = isset( $params['headers'] ) ? $params['headers'] : array();
$res = StreamFile::prepareForStream( $params['src'], $info, $extraHeaders );
if ( $res == StreamFile::NOT_MODIFIED ) {
// do nothing; client cache is up to date
} elseif ( $res == StreamFile::READY_STREAM ) {
wfProfileIn( __METHOD__ . '-send' );
wfProfileIn( __METHOD__ . '-send-' . $this->name );
$status = $this->doStreamFile( $params );
wfProfileOut( __METHOD__ . '-send-' . $this->name );
wfProfileOut( __METHOD__ . '-send' );
if ( !$status->isOK() ) {
// Per bug 41113, nasty things can happen if bad cache entries get
// stuck in cache. It's also possible that this error can come up
// with simple race conditions. Clear out the stat cache to be safe.
$this->clearCache( array( $params['src'] ) );
$this->deleteFileCache( $params['src'] );
trigger_error( "Bad stat cache or race condition for file {$params['src']}." );
}
} else {
$status->fatal( 'backend-fail-stream', $params['src'] );
}
return $status;
}
/**
* @see FileBackendStore::streamFile()
* @return Status
*/
protected function doStreamFile( array $params ) {
$status = Status::newGood();
$fsFile = $this->getLocalReference( $params );
if ( !$fsFile ) {
$status->fatal( 'backend-fail-stream', $params['src'] );
} elseif ( !readfile( $fsFile->getPath() ) ) {
$status->fatal( 'backend-fail-stream', $params['src'] );
}
return $status;
}
final public function directoryExists( array $params ) {
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) {
return false; // invalid storage path
}
if ( $shard !== null ) { // confined to a single container/shard
return $this->doDirectoryExists( $fullCont, $dir, $params );
} else { // directory is on several shards
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
$res = false; // response
foreach ( $this->getContainerSuffixes( $shortCont ) as $suffix ) {
$exists = $this->doDirectoryExists( "{$fullCont}{$suffix}", $dir, $params );
if ( $exists ) {
$res = true;
break; // found one!
} elseif ( $exists === null ) { // error?
$res = null; // if we don't find anything, it is indeterminate
}
}
return $res;
}
}
/**
* @see FileBackendStore::directoryExists()
*
* @param string $container Resolved container name
* @param string $dir Resolved path relative to container
* @param array $params
* @return bool|null
*/
abstract protected function doDirectoryExists( $container, $dir, array $params );
final public function getDirectoryList( array $params ) {
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) { // invalid storage path
return null;
}
if ( $shard !== null ) {
// File listing is confined to a single container/shard
return $this->getDirectoryListInternal( $fullCont, $dir, $params );
} else {
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
// File listing spans multiple containers/shards
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
return new FileBackendStoreShardDirIterator( $this,
$fullCont, $dir, $this->getContainerSuffixes( $shortCont ), $params );
}
}
/**
* Do not call this function from places outside FileBackend
*
* @see FileBackendStore::getDirectoryList()
*
* @param string $container Resolved container name
* @param string $dir Resolved path relative to container
* @param array $params
* @return Traversable|Array|null Returns null on failure
*/
abstract public function getDirectoryListInternal( $container, $dir, array $params );
final public function getFileList( array $params ) {
list( $fullCont, $dir, $shard ) = $this->resolveStoragePath( $params['dir'] );
if ( $dir === null ) { // invalid storage path
return null;
}
if ( $shard !== null ) {
// File listing is confined to a single container/shard
return $this->getFileListInternal( $fullCont, $dir, $params );
} else {
wfDebug( __METHOD__ . ": iterating over all container shards.\n" );
// File listing spans multiple containers/shards
list( , $shortCont, ) = self::splitStoragePath( $params['dir'] );
return new FileBackendStoreShardFileIterator( $this,
$fullCont, $dir, $this->getContainerSuffixes( $shortCont ), $params );
}
}
/**
* Do not call this function from places outside FileBackend
*
* @see FileBackendStore::getFileList()
*
* @param string $container Resolved container name
* @param string $dir Resolved path relative to container
* @param array $params
* @return Traversable|Array|null Returns null on failure
*/
abstract public function getFileListInternal( $container, $dir, array $params );
/**
* Return a list of FileOp objects from a list of operations.
* Do not call this function from places outside FileBackend.
*
* The result must have the same number of items as the input.
* An exception is thrown if an unsupported operation is requested.
*
* @param array $ops Same format as doOperations()
* @return Array List of FileOp objects
* @throws MWException
*/
final public function getOperationsInternal( array $ops ) {
$supportedOps = array(
'store' => 'StoreFileOp',
'copy' => 'CopyFileOp',
'move' => 'MoveFileOp',
'delete' => 'DeleteFileOp',
'create' => 'CreateFileOp',
'describe' => 'DescribeFileOp',
'null' => 'NullFileOp'
);
$performOps = array(); // array of FileOp objects
// Build up ordered array of FileOps...
foreach ( $ops as $operation ) {
$opName = $operation['op'];
if ( isset( $supportedOps[$opName] ) ) {
$class = $supportedOps[$opName];
// Get params for this operation
$params = $operation;
// Append the FileOp class
$performOps[] = new $class( $this, $params );
} else {
throw new MWException( "Operation '$opName' is not supported." );
}
}
return $performOps;
}
/**
* Get a list of storage paths to lock for a list of operations
* Returns an array with LockManager::LOCK_UW (shared locks) and
* LockManager::LOCK_EX (exclusive locks) keys, each corresponding
* to a list of storage paths to be locked. All returned paths are
* normalized.
*
* @param array $performOps List of FileOp objects
* @return Array (LockManager::LOCK_UW => path list, LockManager::LOCK_EX => path list)
*/
final public function getPathsToLockForOpsInternal( array $performOps ) {
// Build up a list of files to lock...
$paths = array( 'sh' => array(), 'ex' => array() );
foreach ( $performOps as $fileOp ) {
$paths['sh'] = array_merge( $paths['sh'], $fileOp->storagePathsRead() );
$paths['ex'] = array_merge( $paths['ex'], $fileOp->storagePathsChanged() );
}
// Optimization: if doing an EX lock anyway, don't also set an SH one
$paths['sh'] = array_diff( $paths['sh'], $paths['ex'] );
// Get a shared lock on the parent directory of each path changed
$paths['sh'] = array_merge( $paths['sh'], array_map( 'dirname', $paths['ex'] ) );
return array(
LockManager::LOCK_UW => $paths['sh'],
LockManager::LOCK_EX => $paths['ex']
);
}
public function getScopedLocksForOps( array $ops, Status $status ) {
$paths = $this->getPathsToLockForOpsInternal( $this->getOperationsInternal( $ops ) );
return array( $this->getScopedFileLocks( $paths, 'mixed', $status ) );
}
final protected function doOperationsInternal( array $ops, array $opts ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
// Fix up custom header name/value pairs...
$ops = array_map( array( $this, 'stripInvalidHeadersFromOp' ), $ops );
// Build up a list of FileOps...
$performOps = $this->getOperationsInternal( $ops );
// Acquire any locks as needed...
if ( empty( $opts['nonLocking'] ) ) {
// Build up a list of files to lock...
$paths = $this->getPathsToLockForOpsInternal( $performOps );
// Try to lock those files for the scope of this function...
$scopeLock = $this->getScopedFileLocks( $paths, 'mixed', $status );
if ( !$status->isOK() ) {
return $status; // abort
}
}
// Clear any file cache entries (after locks acquired)
if ( empty( $opts['preserveCache'] ) ) {
$this->clearCache();
}
// Load from the persistent file and container caches
$this->primeFileCache( $performOps );
$this->primeContainerCache( $performOps );
// Actually attempt the operation batch...
$opts = $this->setConcurrencyFlags( $opts );
$subStatus = FileOpBatch::attempt( $performOps, $opts, $this->fileJournal );
// Merge errors into status fields
$status->merge( $subStatus );
$status->success = $subStatus->success; // not done in merge()
return $status;
}
final protected function doQuickOperationsInternal( array $ops ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$status = Status::newGood();
// Fix up custom header name/value pairs...
$ops = array_map( array( $this, 'stripInvalidHeadersFromOp' ), $ops );
// Clear any file cache entries
$this->clearCache();
$supportedOps = array( 'create', 'store', 'copy', 'move', 'delete', 'null' );
$async = ( $this->parallelize === 'implicit' && count( $ops ) > 1 );
$maxConcurrency = $this->concurrency; // throttle
$statuses = array(); // array of (index => Status)
$fileOpHandles = array(); // list of (index => handle) arrays
$curFileOpHandles = array(); // current handle batch
// Perform the sync-only ops and build up op handles for the async ops...
foreach ( $ops as $index => $params ) {
if ( !in_array( $params['op'], $supportedOps ) ) {
throw new MWException( "Operation '{$params['op']}' is not supported." );
}
$method = $params['op'] . 'Internal'; // e.g. "storeInternal"
$subStatus = $this->$method( array( 'async' => $async ) + $params );
if ( $subStatus->value instanceof FileBackendStoreOpHandle ) { // async
if ( count( $curFileOpHandles ) >= $maxConcurrency ) {
$fileOpHandles[] = $curFileOpHandles; // push this batch
$curFileOpHandles = array();
}
$curFileOpHandles[$index] = $subStatus->value; // keep index
} else { // error or completed
$statuses[$index] = $subStatus; // keep index
}
}
if ( count( $curFileOpHandles ) ) {
$fileOpHandles[] = $curFileOpHandles; // last batch
}
// Do all the async ops that can be done concurrently...
foreach ( $fileOpHandles as $fileHandleBatch ) {
$statuses = $statuses + $this->executeOpHandlesInternal( $fileHandleBatch );
}
// Marshall and merge all the responses...
foreach ( $statuses as $index => $subStatus ) {
$status->merge( $subStatus );
if ( $subStatus->isOK() ) {
$status->success[$index] = true;
++$status->successCount;
} else {
$status->success[$index] = false;
++$status->failCount;
}
}
return $status;
}
/**
* Execute a list of FileBackendStoreOpHandle handles in parallel.
* The resulting Status object fields will correspond
* to the order in which the handles where given.
*
* @param array $handles List of FileBackendStoreOpHandle objects
* @return Array Map of Status objects
* @throws MWException
*/
final public function executeOpHandlesInternal( array $fileOpHandles ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
foreach ( $fileOpHandles as $fileOpHandle ) {
if ( !( $fileOpHandle instanceof FileBackendStoreOpHandle ) ) {
throw new MWException( "Given a non-FileBackendStoreOpHandle object." );
} elseif ( $fileOpHandle->backend->getName() !== $this->getName() ) {
throw new MWException( "Given a FileBackendStoreOpHandle for the wrong backend." );
}
}
$res = $this->doExecuteOpHandlesInternal( $fileOpHandles );
foreach ( $fileOpHandles as $fileOpHandle ) {
$fileOpHandle->closeResources();
}
return $res;
}
/**
* @see FileBackendStore::executeOpHandlesInternal()
* @param array $fileOpHandles
* @throws MWException
* @return Array List of corresponding Status objects
*/
protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
foreach ( $fileOpHandles as $fileOpHandle ) { // OK if empty
throw new MWException( "This backend supports no asynchronous operations." );
}
return array();
}
/**
* Strip long HTTP headers from a file operation.
* Most headers are just numbers, but some are allowed to be long.
* This function is useful for cleaning up headers and avoiding backend
* specific errors, especially in the middle of batch file operations.
*
* @param array $op Same format as doOperation()
* @return Array
*/
protected function stripInvalidHeadersFromOp( array $op ) {
static $longs = array( 'Content-Disposition' );
if ( isset( $op['headers'] ) ) { // op sets HTTP headers
foreach ( $op['headers'] as $name => $value ) {
$maxHVLen = in_array( $name, $longs ) ? INF : 255;
if ( strlen( $name ) > 255 || strlen( $value ) > $maxHVLen ) {
trigger_error( "Header '$name: $value' is too long." );
unset( $op['headers'][$name] );
} elseif ( !strlen( $value ) ) {
$op['headers'][$name] = ''; // null/false => ""
}
}
}
return $op;
}
final public function preloadCache( array $paths ) {
$fullConts = array(); // full container names
foreach ( $paths as $path ) {
list( $fullCont, , ) = $this->resolveStoragePath( $path );
$fullConts[] = $fullCont;
}
// Load from the persistent file and container caches
$this->primeContainerCache( $fullConts );
$this->primeFileCache( $paths );
}
final public function clearCache( array $paths = null ) {
if ( is_array( $paths ) ) {
$paths = array_map( 'FileBackend::normalizeStoragePath', $paths );
$paths = array_filter( $paths, 'strlen' ); // remove nulls
}
if ( $paths === null ) {
$this->cheapCache->clear();
$this->expensiveCache->clear();
} else {
foreach ( $paths as $path ) {
$this->cheapCache->clear( $path );
$this->expensiveCache->clear( $path );
}
}
$this->doClearCache( $paths );
}
/**
* Clears any additional stat caches for storage paths
*
* @see FileBackend::clearCache()
*
* @param array $paths Storage paths (optional)
* @return void
*/
protected function doClearCache( array $paths = null ) {}
/**
* Is this a key/value store where directories are just virtual?
* Virtual directories exists in so much as files exists that are
* prefixed with the directory path followed by a forward slash.
*
* @return bool
*/
abstract protected function directoriesAreVirtual();
/**
* Check if a container name is valid.
* This checks for for length and illegal characters.
*
* @param string $container
* @return bool
*/
final protected static function isValidContainerName( $container ) {
// This accounts for Swift and S3 restrictions while leaving room
// for things like '.xxx' (hex shard chars) or '.seg' (segments).
// This disallows directory separators or traversal characters.
// Note that matching strings URL encode to the same string;
// in Swift, the length restriction is *after* URL encoding.
return preg_match( '/^[a-z0-9][a-z0-9-_]{0,199}$/i', $container );
}
/**
* Splits a storage path into an internal container name,
* an internal relative file name, and a container shard suffix.
* Any shard suffix is already appended to the internal container name.
* This also checks that the storage path is valid and within this backend.
*
* If the container is sharded but a suffix could not be determined,
* this means that the path can only refer to a directory and can only
* be scanned by looking in all the container shards.
*
* @param string $storagePath
* @return Array (container, path, container suffix) or (null, null, null) if invalid
*/
final protected function resolveStoragePath( $storagePath ) {
list( $backend, $container, $relPath ) = self::splitStoragePath( $storagePath );
if ( $backend === $this->name ) { // must be for this backend
$relPath = self::normalizeContainerPath( $relPath );
if ( $relPath !== null ) {
// Get shard for the normalized path if this container is sharded
$cShard = $this->getContainerShard( $container, $relPath );
// Validate and sanitize the relative path (backend-specific)
$relPath = $this->resolveContainerPath( $container, $relPath );
if ( $relPath !== null ) {
// Prepend any wiki ID prefix to the container name
$container = $this->fullContainerName( $container );
if ( self::isValidContainerName( $container ) ) {
// Validate and sanitize the container name (backend-specific)
$container = $this->resolveContainerName( "{$container}{$cShard}" );
if ( $container !== null ) {
return array( $container, $relPath, $cShard );
}
}
}
}
}
return array( null, null, null );
}
/**
* Like resolveStoragePath() except null values are returned if
* the container is sharded and the shard could not be determined
* or if the path ends with '/'. The later case is illegal for FS
* backends and can confuse listings for object store backends.
*
* This function is used when resolving paths that must be valid
* locations for files. Directory and listing functions should
* generally just use resolveStoragePath() instead.
*
* @see FileBackendStore::resolveStoragePath()
*
* @param string $storagePath
* @return Array (container, path) or (null, null) if invalid
*/
final protected function resolveStoragePathReal( $storagePath ) {
list( $container, $relPath, $cShard ) = $this->resolveStoragePath( $storagePath );
if ( $cShard !== null && substr( $relPath, -1 ) !== '/' ) {
return array( $container, $relPath );
}
return array( null, null );
}
/**
* Get the container name shard suffix for a given path.
* Any empty suffix means the container is not sharded.
*
* @param string $container Container name
* @param string $relPath Storage path relative to the container
* @return string|null Returns null if shard could not be determined
*/
final protected function getContainerShard( $container, $relPath ) {
list( $levels, $base, $repeat ) = $this->getContainerHashLevels( $container );
if ( $levels == 1 || $levels == 2 ) {
// Hash characters are either base 16 or 36
$char = ( $base == 36 ) ? '[0-9a-z]' : '[0-9a-f]';
// Get a regex that represents the shard portion of paths.
// The concatenation of the captures gives us the shard.
if ( $levels === 1 ) { // 16 or 36 shards per container
$hashDirRegex = '(' . $char . ')';
} else { // 256 or 1296 shards per container
if ( $repeat ) { // verbose hash dir format (e.g. "a/ab/abc")
$hashDirRegex = $char . '/(' . $char . '{2})';
} else { // short hash dir format (e.g. "a/b/c")
$hashDirRegex = '(' . $char . ')/(' . $char . ')';
}
}
// Allow certain directories to be above the hash dirs so as
// to work with FileRepo (e.g. "archive/a/ab" or "temp/a/ab").
// They must be 2+ chars to avoid any hash directory ambiguity.
$m = array();
if ( preg_match( "!^(?:[^/]{2,}/)*$hashDirRegex(?:/|$)!", $relPath, $m ) ) {
return '.' . implode( '', array_slice( $m, 1 ) );
}
return null; // failed to match
}
return ''; // no sharding
}
/**
* Check if a storage path maps to a single shard.
* Container dirs like "a", where the container shards on "x/xy",
* can reside on several shards. Such paths are tricky to handle.
*
* @param string $storagePath Storage path
* @return bool
*/
final public function isSingleShardPathInternal( $storagePath ) {
list( , , $shard ) = $this->resolveStoragePath( $storagePath );
return ( $shard !== null );
}
/**
* Get the sharding config for a container.
* If greater than 0, then all file storage paths within
* the container are required to be hashed accordingly.
*
* @param string $container
* @return Array (integer levels, integer base, repeat flag) or (0, 0, false)
*/
final protected function getContainerHashLevels( $container ) {
if ( isset( $this->shardViaHashLevels[$container] ) ) {
$config = $this->shardViaHashLevels[$container];
$hashLevels = (int)$config['levels'];
if ( $hashLevels == 1 || $hashLevels == 2 ) {
$hashBase = (int)$config['base'];
if ( $hashBase == 16 || $hashBase == 36 ) {
return array( $hashLevels, $hashBase, $config['repeat'] );
}
}
}
return array( 0, 0, false ); // no sharding
}
/**
* Get a list of full container shard suffixes for a container
*
* @param string $container
* @return Array
*/
final protected function getContainerSuffixes( $container ) {
$shards = array();
list( $digits, $base ) = $this->getContainerHashLevels( $container );
if ( $digits > 0 ) {
$numShards = pow( $base, $digits );
for ( $index = 0; $index < $numShards; $index++ ) {
$shards[] = '.' . wfBaseConvert( $index, 10, $base, $digits );
}
}
return $shards;
}
/**
* Get the full container name, including the wiki ID prefix
*
* @param string $container
* @return string
*/
final protected function fullContainerName( $container ) {
if ( $this->wikiId != '' ) {
return "{$this->wikiId}-$container";
} else {
return $container;
}
}
/**
* Resolve a container name, checking if it's allowed by the backend.
* This is intended for internal use, such as encoding illegal chars.
* Subclasses can override this to be more restrictive.
*
* @param string $container
* @return string|null
*/
protected function resolveContainerName( $container ) {
return $container;
}
/**
* Resolve a relative storage path, checking if it's allowed by the backend.
* This is intended for internal use, such as encoding illegal chars or perhaps
* getting absolute paths (e.g. FS based backends). Note that the relative path
* may be the empty string (e.g. the path is simply to the container).
*
* @param string $container Container name
* @param string $relStoragePath Storage path relative to the container
* @return string|null Path or null if not valid
*/
protected function resolveContainerPath( $container, $relStoragePath ) {
return $relStoragePath;
}
/**
* Get the cache key for a container
*
* @param string $container Resolved container name
* @return string
*/
private function containerCacheKey( $container ) {
return wfMemcKey( 'backend', $this->getName(), 'container', $container );
}
/**
* Set the cached info for a container
*
* @param string $container Resolved container name
* @param array $val Information to cache
* @return void
*/
final protected function setContainerCache( $container, array $val ) {
$this->memCache->add( $this->containerCacheKey( $container ), $val, 14 * 86400 );
}
/**
* Delete the cached info for a container.
* The cache key is salted for a while to prevent race conditions.
*
* @param string $container Resolved container name
* @return void
*/
final protected function deleteContainerCache( $container ) {
if ( !$this->memCache->set( $this->containerCacheKey( $container ), 'PURGED', 300 ) ) {
trigger_error( "Unable to delete stat cache for container $container." );
}
}
/**
* Do a batch lookup from cache for container stats for all containers
* used in a list of container names, storage paths, or FileOp objects.
* This loads the persistent cache values into the process cache.
*
* @param Array $items
* @return void
*/
final protected function primeContainerCache( array $items ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$paths = array(); // list of storage paths
$contNames = array(); // (cache key => resolved container name)
// Get all the paths/containers from the items...
foreach ( $items as $item ) {
if ( $item instanceof FileOp ) {
$paths = array_merge( $paths, $item->storagePathsRead() );
$paths = array_merge( $paths, $item->storagePathsChanged() );
} elseif ( self::isStoragePath( $item ) ) {
$paths[] = $item;
} elseif ( is_string( $item ) ) { // full container name
$contNames[$this->containerCacheKey( $item )] = $item;
}
}
// Get all the corresponding cache keys for paths...
foreach ( $paths as $path ) {
list( $fullCont, , ) = $this->resolveStoragePath( $path );
if ( $fullCont !== null ) { // valid path for this backend
$contNames[$this->containerCacheKey( $fullCont )] = $fullCont;
}
}
$contInfo = array(); // (resolved container name => cache value)
// Get all cache entries for these container cache keys...
$values = $this->memCache->getMulti( array_keys( $contNames ) );
foreach ( $values as $cacheKey => $val ) {
$contInfo[$contNames[$cacheKey]] = $val;
}
// Populate the container process cache for the backend...
$this->doPrimeContainerCache( array_filter( $contInfo, 'is_array' ) );
}
/**
* Fill the backend-specific process cache given an array of
* resolved container names and their corresponding cached info.
* Only containers that actually exist should appear in the map.
*
* @param array $containerInfo Map of resolved container names to cached info
* @return void
*/
protected function doPrimeContainerCache( array $containerInfo ) {}
/**
* Get the cache key for a file path
*
* @param string $path Normalized storage path
* @return string
*/
private function fileCacheKey( $path ) {
return wfMemcKey( 'backend', $this->getName(), 'file', sha1( $path ) );
}
/**
* Set the cached stat info for a file path.
* Negatives (404s) are not cached. By not caching negatives, we can skip cache
* salting for the case when a file is created at a path were there was none before.
*
* @param string $path Storage path
* @param array $val Stat information to cache
* @return void
*/
final protected function setFileCache( $path, array $val ) {
$path = FileBackend::normalizeStoragePath( $path );
if ( $path === null ) {
return; // invalid storage path
}
$age = time() - wfTimestamp( TS_UNIX, $val['mtime'] );
$ttl = min( 7 * 86400, max( 300, floor( .1 * $age ) ) );
$this->memCache->add( $this->fileCacheKey( $path ), $val, $ttl );
}
/**
* Delete the cached stat info for a file path.
* The cache key is salted for a while to prevent race conditions.
* Since negatives (404s) are not cached, this does not need to be called when
* a file is created at a path were there was none before.
*
* @param string $path Storage path
* @return void
*/
final protected function deleteFileCache( $path ) {
$path = FileBackend::normalizeStoragePath( $path );
if ( $path === null ) {
return; // invalid storage path
}
if ( !$this->memCache->set( $this->fileCacheKey( $path ), 'PURGED', 300 ) ) {
trigger_error( "Unable to delete stat cache for file $path." );
}
}
/**
* Do a batch lookup from cache for file stats for all paths
* used in a list of storage paths or FileOp objects.
* This loads the persistent cache values into the process cache.
*
* @param array $items List of storage paths or FileOps
* @return void
*/
final protected function primeFileCache( array $items ) {
$section = new ProfileSection( __METHOD__ . "-{$this->name}" );
$paths = array(); // list of storage paths
$pathNames = array(); // (cache key => storage path)
// Get all the paths/containers from the items...
foreach ( $items as $item ) {
if ( $item instanceof FileOp ) {
$paths = array_merge( $paths, $item->storagePathsRead() );
$paths = array_merge( $paths, $item->storagePathsChanged() );
} elseif ( self::isStoragePath( $item ) ) {
$paths[] = FileBackend::normalizeStoragePath( $item );
}
}
// Get rid of any paths that failed normalization...
$paths = array_filter( $paths, 'strlen' ); // remove nulls
// Get all the corresponding cache keys for paths...
foreach ( $paths as $path ) {
list( , $rel, ) = $this->resolveStoragePath( $path );
if ( $rel !== null ) { // valid path for this backend
$pathNames[$this->fileCacheKey( $path )] = $path;
}
}
// Get all cache entries for these container cache keys...
$values = $this->memCache->getMulti( array_keys( $pathNames ) );
foreach ( $values as $cacheKey => $val ) {
if ( is_array( $val ) ) {
$path = $pathNames[$cacheKey];
$this->cheapCache->set( $path, 'stat', $val );
if ( isset( $val['sha1'] ) ) { // some backends store SHA-1 as metadata
$this->cheapCache->set( $path, 'sha1',
array( 'hash' => $val['sha1'], 'latest' => $val['latest'] ) );
}
}
}
}
/**
* Set the 'concurrency' option from a list of operation options
*
* @param array $opts Map of operation options
* @return Array
*/
final protected function setConcurrencyFlags( array $opts ) {
$opts['concurrency'] = 1; // off
if ( $this->parallelize === 'implicit' ) {
if ( !isset( $opts['parallelize'] ) || $opts['parallelize'] ) {
$opts['concurrency'] = $this->concurrency;
}
} elseif ( $this->parallelize === 'explicit' ) {
if ( !empty( $opts['parallelize'] ) ) {
$opts['concurrency'] = $this->concurrency;
}
}
return $opts;
}
/**
* Get the content type to use in HEAD/GET requests for a file
*
* @param string $storagePath
* @param string|null $content File data
* @param string|null $fsPath File system path
* @return MIME type
*/
protected function getContentType( $storagePath, $content, $fsPath ) {
return call_user_func_array( $this->mimeCallback, func_get_args() );
}
}
/**
* FileBackendStore helper class for performing asynchronous file operations.
*
* For example, calling FileBackendStore::createInternal() with the "async"
* param flag may result in a Status that contains this object as a value.
* This class is largely backend-specific and is mostly just "magic" to be
* passed to FileBackendStore::executeOpHandlesInternal().
*/
abstract class FileBackendStoreOpHandle {
/** @var Array */
public $params = array(); // params to caller functions
/** @var FileBackendStore */
public $backend;
/** @var Array */
public $resourcesToClose = array();
public $call; // string; name that identifies the function called
/**
* Close all open file handles
*
* @return void
*/
public function closeResources() {
array_map( 'fclose', $this->resourcesToClose );
}
}
/**
* FileBackendStore helper function to handle listings that span container shards.
* Do not use this class from places outside of FileBackendStore.
*
* @ingroup FileBackend
*/
abstract class FileBackendStoreShardListIterator extends FilterIterator {
/** @var FileBackendStore */
protected $backend;
/** @var Array */
protected $params;
protected $container; // string; full container name
protected $directory; // string; resolved relative path
/** @var Array */
protected $multiShardPaths = array(); // (rel path => 1)
/**
* @param FileBackendStore $backend
* @param string $container Full storage container name
* @param string $dir Storage directory relative to container
* @param array $suffixes List of container shard suffixes
* @param array $params
*/
public function __construct(
FileBackendStore $backend, $container, $dir, array $suffixes, array $params
) {
$this->backend = $backend;
$this->container = $container;
$this->directory = $dir;
$this->params = $params;
$iter = new AppendIterator();
foreach ( $suffixes as $suffix ) {
$iter->append( $this->listFromShard( $this->container . $suffix ) );
}
parent::__construct( $iter );
}
public function accept() {
$rel = $this->getInnerIterator()->current(); // path relative to given directory
$path = $this->params['dir'] . "/{$rel}"; // full storage path
if ( $this->backend->isSingleShardPathInternal( $path ) ) {
return true; // path is only on one shard; no issue with duplicates
} elseif ( isset( $this->multiShardPaths[$rel] ) ) {
// Don't keep listing paths that are on multiple shards
return false;
} else {
$this->multiShardPaths[$rel] = 1;
return true;
}
}
public function rewind() {
parent::rewind();
$this->multiShardPaths = array();
}
/**
* Get the list for a given container shard
*
* @param string $container Resolved container name
* @return Iterator
*/
abstract protected function listFromShard( $container );
}
/**
* Iterator for listing directories
*/
class FileBackendStoreShardDirIterator extends FileBackendStoreShardListIterator {
protected function listFromShard( $container ) {
$list = $this->backend->getDirectoryListInternal(
$container, $this->directory, $this->params );
if ( $list === null ) {
return new ArrayIterator( array() );
} else {
return is_array( $list ) ? new ArrayIterator( $list ) : $list;
}
}
}
/**
* Iterator for listing regular files
*/
class FileBackendStoreShardFileIterator extends FileBackendStoreShardListIterator {
protected function listFromShard( $container ) {
$list = $this->backend->getFileListInternal(
$container, $this->directory, $this->params );
if ( $list === null ) {
return new ArrayIterator( array() );
} else {
return is_array( $list ) ? new ArrayIterator( $list ) : $list;
}
}
}