MediaWiki
1.23.3
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Proxy backend that mirrors writes to several internal backends. More...
Public Member Functions | |
__construct (array $config) | |
Construct a proxy backend that consists of several internal backends. More... | |
accessibilityCheck (array $paths) | |
Check that a set of file paths are usable across all internal backends. More... | |
clearCache (array $paths=null) | |
Invalidate any in-process file stat and property cache. More... | |
concatenate (array $params) | |
Concatenate a list of storage files into a single file system file. More... | |
consistencyCheck (array $paths) | |
Check that a set of files are consistent across all internal backends. More... | |
directoryExists (array $params) | |
Check if a directory exists at a given storage path. More... | |
fileExists (array $params) | |
Check if a file exists at a storage path in the backend. More... | |
getDirectoryList (array $params) | |
Get an iterator to list all directories under a storage directory. More... | |
getFeatures () | |
Get the a bitfield of extra features supported by the backend medium. More... | |
getFileContentsMulti (array $params) | |
Like getFileContents() except it takes an array of storage paths and returns a map of storage paths to strings (or null on failure). More... | |
getFileHttpUrl (array $params) | |
Return an HTTP URL to a given file that requires no authentication to use. More... | |
getFileList (array $params) | |
Get an iterator to list all stored files under a storage directory. More... | |
getFileProps (array $params) | |
Get the properties of the file at a storage path in the backend. More... | |
getFileSha1Base36 (array $params) | |
Get a SHA-1 hash of the file at a storage path in the backend. More... | |
getFileSize (array $params) | |
Get the size (bytes) of a file at a storage path in the backend. More... | |
getFileStat (array $params) | |
Get quick information about a file at a storage path in the backend. More... | |
getFileTimestamp (array $params) | |
Get the last-modified timestamp of the file at a storage path. More... | |
getFileXAttributes (array $params) | |
Get metadata about a file at a storage path in the backend. More... | |
getLocalCopyMulti (array $params) | |
Like getLocalCopy() except it takes an array of storage paths and returns a map of storage paths to TempFSFile objects (or null on failure). More... | |
getLocalReferenceMulti (array $params) | |
Like getLocalReference() except it takes an array of storage paths and returns a map of storage paths to FSFile objects (or null on failure). More... | |
getScopedLocksForOps (array $ops, Status $status) | |
Get an array of scoped locks needed for a batch of file operations. More... | |
preloadCache (array $paths) | |
Preload persistent file stat cache and property cache into in-process cache. More... | |
preloadFileStat (array $params) | |
Preload file stat information (concurrently if possible) into in-process cache. More... | |
resyncFiles (array $paths) | |
Check that a set of files are consistent across all internal backends and re-synchronize those files againt the "multi master" if needed. More... | |
streamFile (array $params) | |
Stream the file at a storage path in the backend. More... | |
Public Member Functions inherited from FileBackend | |
clean (array $params) | |
Delete a storage directory if it is empty. More... | |
copy (array $params, array $opts=array()) | |
Performs a single copy operation. More... | |
create (array $params, array $opts=array()) | |
Performs a single create operation. More... | |
delete (array $params, array $opts=array()) | |
Performs a single delete operation. More... | |
describe (array $params, array $opts=array()) | |
Performs a single describe operation. More... | |
doOperation (array $op, array $opts=array()) | |
Same as doOperations() except it takes a single operation. More... | |
doOperations (array $ops, array $opts=array()) | |
This is the main entry point into the backend for write operations. More... | |
doQuickOperation (array $op) | |
Same as doQuickOperations() except it takes a single operation. More... | |
doQuickOperations (array $ops, array $opts=array()) | |
Perform a set of independent file operations on some files. More... | |
getContainerStoragePath ( $container) | |
Get the storage path for the given container for this backend. More... | |
getFileContents (array $params) | |
Get the contents of a file at a storage path in the backend. More... | |
getJournal () | |
Get the file journal object for this backend. More... | |
getLocalCopy (array $params) | |
Get a local copy on disk of the file at a storage path in the backend. More... | |
getLocalReference (array $params) | |
Returns a file system file, identical to the file at a storage path. More... | |
getName () | |
Get the unique backend name. More... | |
getReadOnlyReason () | |
Get an explanatory message if this backend is read-only. More... | |
getRootStoragePath () | |
Get the root storage path of this backend. More... | |
getScopedFileLocks (array $paths, $type, Status $status) | |
Lock the files at the given storage paths in the backend. More... | |
getTopDirectoryList (array $params) | |
Same as FileBackend::getDirectoryList() except only lists directories that are immediately under the given directory. More... | |
getTopFileList (array $params) | |
Same as FileBackend::getFileList() except only lists files that are immediately under the given directory. More... | |
getWikiId () | |
Get the wiki identifier used for this backend (possibly empty). More... | |
hasFeatures ( $bitfield) | |
Check if the backend medium supports a field of extra features. More... | |
isReadOnly () | |
Check if this backend is read-only. More... | |
lockFiles (array $paths, $type) | |
Lock the files at the given storage paths in the backend. More... | |
move (array $params, array $opts=array()) | |
Performs a single move operation. More... | |
prepare (array $params) | |
Prepare a storage directory for usage. More... | |
publish (array $params) | |
Remove measures to block web access to a storage directory and the container it belongs to. More... | |
quickCopy (array $params) | |
Performs a single quick copy operation. More... | |
quickCreate (array $params) | |
Performs a single quick create operation. More... | |
quickDelete (array $params) | |
Performs a single quick delete operation. More... | |
quickDescribe (array $params) | |
Performs a single quick describe operation. More... | |
quickMove (array $params) | |
Performs a single quick move operation. More... | |
quickStore (array $params) | |
Performs a single quick store operation. More... | |
secure (array $params) | |
Take measures to block web access to a storage directory and the container it belongs to. More... | |
store (array $params, array $opts=array()) | |
Performs a single store operation. More... | |
unlockFiles (array $paths, $type) | |
Unlock the files at the given storage paths in the backend. More... | |
Public Attributes | |
const | CHECK_SHA1 = 4 |
const | CHECK_SIZE = 1 |
const | CHECK_TIME = 2 |
Public Attributes inherited from FileBackend | |
const | ATTR_HEADERS = 1 |
Flags for supported features. More... | |
const | ATTR_METADATA = 2 |
Protected Member Functions | |
doClean (array $params) | |
doOperationsInternal (array $ops, array $opts) | |
doPrepare (array $params) | |
doPublish (array $params) | |
doQuickOperationsInternal (array $ops) | |
doSecure (array $params) | |
fileStoragePathsForOps (array $ops) | |
Get a list of file storage paths to read or write for a list of operations. More... | |
replicateContainerDirChanges ( $path) | |
substOpBatchPaths (array $ops, FileBackendStore $backend) | |
Substitute the backend name in storage path parameters for a set of operations with that of a given internal backend. More... | |
substOpPaths (array $ops, FileBackendStore $backend) | |
Same as substOpBatchPaths() but for a single operation. More... | |
substPaths ( $paths, FileBackendStore $backend) | |
Substitute the backend of storage paths with an internal backend's name. More... | |
unsubstPaths ( $paths) | |
Substitute the backend of internal storage paths with the proxy backend's name. More... | |
Protected Member Functions inherited from FileBackend | |
getScopedPHPBehaviorForOps () | |
Enter file operation scope. More... | |
Protected Attributes | |
string bool | $autoResync = false |
array | $backends = array() |
Prioritized list of FileBackendStore objects. More... | |
int | $masterIndex = -1 |
Index of master backend *. More... | |
array | $noPushDirConts = array() |
bool | $noPushQuickOps = false |
int | $syncChecks = 0 |
Bitfield *. More... | |
Protected Attributes inherited from FileBackend | |
int | $concurrency |
How many operations can be done in parallel *. More... | |
FileJournal | $fileJournal |
LockManager | $lockManager |
string | $name |
Unique backend name *. More... | |
string | $parallelize |
When to do operations in parallel *. More... | |
string | $readOnly |
Read-only explanation message *. More... | |
string | $wikiId |
Unique wiki name *. More... | |
Additional Inherited Members | |
Static Public Member Functions inherited from FileBackend | |
static | extensionFromPath ( $path) |
Get the final extension from a storage or FS path. More... | |
static | isPathTraversalFree ( $path) |
Check if a relative path has no directory traversals. More... | |
static | isStoragePath ( $path) |
Check if a given path is a "mwstore://" path. More... | |
static | makeContentDisposition ( $type, $filename='') |
Build a Content-Disposition header value per RFC 6266. More... | |
static | normalizeStoragePath ( $storagePath) |
Normalize a storage path by cleaning up directory separators. More... | |
static | parentStoragePath ( $storagePath) |
Get the parent storage directory of a storage path. More... | |
static | splitStoragePath ( $storagePath) |
Split a storage path into a backend name, a container name, and a relative file path. More... | |
Static Protected Member Functions inherited from FileBackend | |
static | normalizeContainerPath ( $path) |
Validate and normalize a relative storage path. More... | |
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, in the order defined. If an operation fails on one backend it will be rolled back from the others.
Definition at line 42 of file FileBackendMultiWrite.php.
FileBackendMultiWrite::__construct | ( | array | $config | ) |
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:
array | $config |
FileBackendError |
Reimplemented from FileBackend.
Definition at line 91 of file FileBackendMultiWrite.php.
References FileBackend\$fileJournal, FileBackend\$name, FileBackend\$wikiId, array(), as, CHECK_SIZE, and FileBackendGroup\singleton().
FileBackendMultiWrite::accessibilityCheck | ( | array | $paths | ) |
Check that a set of file paths are usable across all internal backends.
array | $paths | List of storage paths |
Definition at line 276 of file FileBackendMultiWrite.php.
References $path, as, Status\newGood(), and substPaths().
Referenced by doOperationsInternal().
FileBackendMultiWrite::clearCache | ( | array | $paths = null | ) |
Invalidate any in-process file stat and property cache.
If $paths is given, then only the cache for those files will be cleared.
array | $paths | Storage paths (optional) |
Reimplemented from FileBackend.
Definition at line 652 of file FileBackendMultiWrite.php.
References as, and substPaths().
Referenced by doOperationsInternal().
FileBackendMultiWrite::concatenate | ( | array | $params | ) |
Concatenate a list of storage files into a single file system file.
The target path should refer to a file that is already locked or otherwise safe from modification from other processes. Normally, the file will be a new temp file, which should be adequate.
array | $params | Operation parameters, include:
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Reimplemented from FileBackend.
Definition at line 533 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::consistencyCheck | ( | array | $paths | ) |
Check that a set of files are consistent across all internal backends.
array | $paths | List of storage paths |
Definition at line 210 of file FileBackendMultiWrite.php.
References $masterIndex, $params, $path, array(), as, Status\newGood(), substOpPaths(), TS_UNIX, and wfTimestamp().
Referenced by doOperationsInternal().
FileBackendMultiWrite::directoryExists | ( | array | $params | ) |
Check if a directory exists at a given storage path.
Backends using key/value stores will check if the path is a virtual directory, meaning there are files under the given directory.
Storage backends with eventual consistency might return stale data.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 630 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
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Reimplemented from FileBackend.
Definition at line 520 of file FileBackendMultiWrite.php.
References as, Status\newGood(), replicateContainerDirChanges(), and substOpPaths().
Reimplemented from FileBackend.
Definition at line 143 of file FileBackendMultiWrite.php.
References $masterIndex, accessibilityCheck(), as, clearCache(), consistencyCheck(), FormatJson\encode(), fileStoragePathsForOps(), getScopedLocksForOps(), Status\newGood(), resyncFiles(), substOpBatchPaths(), and wfDebugLog().
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Reimplemented from FileBackend.
Definition at line 481 of file FileBackendMultiWrite.php.
References as, Status\newGood(), replicateContainerDirChanges(), and substOpPaths().
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Reimplemented from FileBackend.
Definition at line 507 of file FileBackendMultiWrite.php.
References as, Status\newGood(), replicateContainerDirChanges(), and substOpPaths().
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Reimplemented from FileBackend.
Definition at line 446 of file FileBackendMultiWrite.php.
References $masterIndex, as, Status\newGood(), and substOpBatchPaths().
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Reimplemented from FileBackend.
Definition at line 494 of file FileBackendMultiWrite.php.
References as, Status\newGood(), replicateContainerDirChanges(), and substOpPaths().
FileBackendMultiWrite::fileExists | ( | array | $params | ) |
Check if a file exists at a storage path in the backend.
This returns false if only a directory exists at the path.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 540 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
Referenced by fileStoragePathsForOps().
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Get a list of file storage paths to read or write for a list of operations.
array | $ops | Same format as doOperations() |
Definition at line 358 of file FileBackendMultiWrite.php.
References array(), as, and fileExists().
Referenced by doOperationsInternal().
FileBackendMultiWrite::getDirectoryList | ( | array | $params | ) |
Get an iterator to list all directories under a storage directory.
If the directory is of the form "mwstore://backend/container", then all directories in the container will be listed. If the directory is of form "mwstore://backend/container/dir", then all directories directly under that directory will be listed. Results will be storage directories relative to the given directory.
Storage backends with eventual consistency might return stale data.
Failures during iteration can result in FileBackendError exceptions (since 1.22).
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 636 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFeatures | ( | ) |
Get the a bitfield of extra features supported by the backend medium.
Reimplemented from FileBackend.
Definition at line 648 of file FileBackendMultiWrite.php.
References $masterIndex.
FileBackendMultiWrite::getFileContentsMulti | ( | array | $params | ) |
Like getFileContents() except it takes an array of storage paths and returns a map of storage paths to strings (or null on failure).
The map keys (paths) are in the same order as the provided list of paths.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 570 of file FileBackendMultiWrite.php.
References $masterIndex, $path, array(), as, substOpPaths(), and unsubstPaths().
FileBackendMultiWrite::getFileHttpUrl | ( | array | $params | ) |
Return an HTTP URL to a given file that requires no authentication to use.
The URL may be pre-authenticated (via some token in the URL) and temporary. This will return null if the backend cannot make an HTTP URL for the file.
This is useful for key/value stores when using scripts that seek around large files and those scripts (and the backend) support HTTP Range headers. Otherwise, one would need to use getLocalReference(), which involves loading the entire file on to local disk.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 624 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileList | ( | array | $params | ) |
Get an iterator to list all stored files under a storage directory.
If the directory is of the form "mwstore://backend/container", then all files in the container will be listed. If the directory is of form "mwstore://backend/container/dir", then all files under that directory will be listed. Results will be storage paths relative to the given directory.
Storage backends with eventual consistency might return stale data.
Failures during iteration can result in FileBackendError exceptions (since 1.22).
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 642 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileProps | ( | array | $params | ) |
Get the properties of the file at a storage path in the backend.
This gives the result of FSFile::getProps() on a local copy of the file.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 588 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileSha1Base36 | ( | array | $params | ) |
Get a SHA-1 hash of the file at a storage path in the backend.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 582 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileSize | ( | array | $params | ) |
Get the size (bytes) of a file at a storage path in the backend.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 552 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileStat | ( | array | $params | ) |
Get quick information about a file at a storage path in the backend.
If the file does not exist, then this returns false. Otherwise, the result is an associative array that includes:
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 558 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileTimestamp | ( | array | $params | ) |
Get the last-modified timestamp of the file at a storage path.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 546 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getFileXAttributes | ( | array | $params | ) |
Get metadata about a file at a storage path in the backend.
If the file does not exist, then this returns false. Otherwise, the result is an associative array that includes:
Use FileBackend::hasFeatures() to check how well this is supported.
array | $params | $params include:
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Reimplemented from FileBackend.
Definition at line 564 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
FileBackendMultiWrite::getLocalCopyMulti | ( | array | $params | ) |
Like getLocalCopy() except it takes an array of storage paths and returns a map of storage paths to TempFSFile objects (or null on failure).
The map keys (paths) are in the same order as the provided list of paths.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 612 of file FileBackendMultiWrite.php.
References $masterIndex, $path, array(), as, substOpPaths(), and unsubstPaths().
FileBackendMultiWrite::getLocalReferenceMulti | ( | array | $params | ) |
Like getLocalReference() except it takes an array of storage paths and returns a map of storage paths to FSFile objects (or null on failure).
The map keys (paths) are in the same order as the provided list of paths.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 600 of file FileBackendMultiWrite.php.
References $masterIndex, $path, array(), as, substOpPaths(), and unsubstPaths().
Get an array of scoped locks needed for a batch of file operations.
Normally, FileBackend::doOperations() handles locking, unless the 'nonLocking' param is passed in. This function is useful if you want the files to be locked for a broader scope than just when the files are changing. For example, if you need to update DB metadata, you may want to keep the files locked until finished.
array | $ops | List of file operations to FileBackend::doOperations() |
Status | $status | Status to update on lock/unlock |
Reimplemented from FileBackend.
Definition at line 669 of file FileBackendMultiWrite.php.
References $masterIndex, array(), FileBackend\getScopedFileLocks(), LockManager\LOCK_EX, LockManager\LOCK_UW, substOpBatchPaths(), and unsubstPaths().
Referenced by doOperationsInternal().
FileBackendMultiWrite::preloadCache | ( | array | $paths | ) |
Preload persistent file stat cache and property cache into in-process cache.
This should be used when stat calls will be made on a known list of a many files.
array | $paths | Storage paths |
Reimplemented from FileBackend.
Definition at line 659 of file FileBackendMultiWrite.php.
References $masterIndex, and substPaths().
FileBackendMultiWrite::preloadFileStat | ( | array | $params | ) |
Preload file stat information (concurrently if possible) into in-process cache.
This should be used when stat calls will be made on a known list of a many files.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 664 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
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string | $path | Storage path |
Definition at line 475 of file FileBackendMultiWrite.php.
References $path, list, and FileBackend\splitStoragePath().
Referenced by doClean(), doPrepare(), doPublish(), and doSecure().
FileBackendMultiWrite::resyncFiles | ( | array | $paths | ) |
Check that a set of files are consistent across all internal backends and re-synchronize those files againt the "multi master" if needed.
array | $paths | List of storage paths |
Definition at line 301 of file FileBackendMultiWrite.php.
References $masterIndex, $path, array(), as, name, Status\newGood(), and substPaths().
Referenced by doOperationsInternal().
FileBackendMultiWrite::streamFile | ( | array | $params | ) |
Stream the file at a storage path in the backend.
If the file does not exists, an HTTP 404 error will be given. Appropriate HTTP headers (Status, Content-Type, Content-Length) will be sent if streaming began, while none will be sent otherwise. Implementations should flush the output buffer before sending data.
array | $params | Parameters include:
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Reimplemented from FileBackend.
Definition at line 594 of file FileBackendMultiWrite.php.
References $masterIndex, and substOpPaths().
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Substitute the backend name in storage path parameters for a set of operations with that of a given internal backend.
array | $ops | List of file operation arrays |
FileBackendStore | $backend |
Definition at line 389 of file FileBackendMultiWrite.php.
References array(), as, and substPaths().
Referenced by doOperationsInternal(), doQuickOperationsInternal(), getScopedLocksForOps(), and substOpPaths().
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Same as substOpBatchPaths() but for a single operation.
array | $ops | File operation array |
FileBackendStore | $backend |
Definition at line 411 of file FileBackendMultiWrite.php.
References array(), and substOpBatchPaths().
Referenced by concatenate(), consistencyCheck(), directoryExists(), doClean(), doPrepare(), doPublish(), doSecure(), fileExists(), getDirectoryList(), getFileContentsMulti(), getFileHttpUrl(), getFileList(), getFileProps(), getFileSha1Base36(), getFileSize(), getFileStat(), getFileTimestamp(), getFileXAttributes(), getLocalCopyMulti(), getLocalReferenceMulti(), preloadFileStat(), and streamFile().
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Substitute the backend of storage paths with an internal backend's name.
array | string | $paths | List of paths or single string path |
FileBackendStore | $backend |
Definition at line 424 of file FileBackendMultiWrite.php.
References StringUtils\escapeRegexReplacement(), and name.
Referenced by accessibilityCheck(), clearCache(), preloadCache(), resyncFiles(), and substOpBatchPaths().
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Substitute the backend of internal storage paths with the proxy backend's name.
array | string | $paths | List of paths or single string path |
Definition at line 438 of file FileBackendMultiWrite.php.
References StringUtils\escapeRegexReplacement().
Referenced by getFileContentsMulti(), getLocalCopyMulti(), getLocalReferenceMulti(), and getScopedLocksForOps().
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Definition at line 51 of file FileBackendMultiWrite.php.
Prioritized list of FileBackendStore objects.
array of (backend index => backends)
Definition at line 45 of file FileBackendMultiWrite.php.
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Index of master backend *.
Definition at line 47 of file FileBackendMultiWrite.php.
Referenced by concatenate(), consistencyCheck(), directoryExists(), doOperationsInternal(), doQuickOperationsInternal(), fileExists(), getDirectoryList(), getFeatures(), getFileContentsMulti(), getFileHttpUrl(), getFileList(), getFileProps(), getFileSha1Base36(), getFileSize(), getFileStat(), getFileTimestamp(), getFileXAttributes(), getLocalCopyMulti(), getLocalReferenceMulti(), getScopedLocksForOps(), preloadCache(), preloadFileStat(), resyncFiles(), and streamFile().
Definition at line 53 of file FileBackendMultiWrite.php.
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Definition at line 55 of file FileBackendMultiWrite.php.
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Bitfield *.
Definition at line 49 of file FileBackendMultiWrite.php.
const FileBackendMultiWrite::CHECK_SHA1 = 4 |
Definition at line 60 of file FileBackendMultiWrite.php.
const FileBackendMultiWrite::CHECK_SIZE = 1 |
Definition at line 58 of file FileBackendMultiWrite.php.
Referenced by __construct().
const FileBackendMultiWrite::CHECK_TIME = 2 |
Definition at line 59 of file FileBackendMultiWrite.php.