Base class for all file backend classes (including multi-write backends). More...

Inheritance diagram for FileBackend:

Collaboration diagram for FileBackend:

Public Member Functions
	__construct (array $config)
	Create a new backend instance from configuration.
	clean (array $params)
	Delete a storage directory if it is empty.
	clearCache (array $paths=null)
	Invalidate any in-process file stat and property cache.
	concatenate (array $params)
	Concatenate a list of storage files into a single file system file.
	copy (array $params, array $opts=array())
	Performs a single copy operation.
	create (array $params, array $opts=array())
	Performs a single create operation.
	delete (array $params, array $opts=array())
	Performs a single delete operation.
	describe (array $params, array $opts=array())
	Performs a single describe operation.
	directoryExists (array $params)
	Check if a directory exists at a given storage path.
	doOperation (array $op, array $opts=array())
	Same as doOperations() except it takes a single operation.
	doOperations (array $ops, array $opts=array())
	This is the main entry point into the backend for write operations.
	doQuickOperation (array $op)
	Same as doQuickOperations() except it takes a single operation.
	doQuickOperations (array $ops, array $opts=array())
	Perform a set of independent file operations on some files.
	fileExists (array $params)
	Check if a file exists at a storage path in the backend.
	getContainerStoragePath ($container)
	Get the storage path for the given container for this backend.
	getDirectoryList (array $params)
	Get an iterator to list all directories under a storage directory.
	getFeatures ()
	Get the a bitfield of extra features supported by the backend medium.
	getFileContents (array $params)
	Get the contents of a file at a storage path in the backend.
	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).
	getFileHttpUrl (array $params)
	Return an HTTP URL to a given file that requires no authentication to use.
	getFileList (array $params)
	Get an iterator to list all stored files under a storage directory.
	getFileProps (array $params)
	Get the properties of the file at a storage path in the backend.
	getFileSha1Base36 (array $params)
	Get a SHA-1 hash of the file at a storage path in the backend.
	getFileSize (array $params)
	Get the size (bytes) of a file at a storage path in the backend.
	getFileStat (array $params)
	Get quick information about a file at a storage path in the backend.
	getFileTimestamp (array $params)
	Get the last-modified timestamp of the file at a storage path.
	getFileXAttributes (array $params)
	Get metadata about a file at a storage path in the backend.
	getJournal ()
	Get the file journal object for this backend.
	getLocalCopy (array $params)
	Get a local copy on disk of the file at a storage path in the backend.
	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).
	getLocalReference (array $params)
	Returns a file system file, identical to the file at a storage path.
	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).
	getName ()
	Get the unique backend name.
	getReadOnlyReason ()
	Get an explanatory message if this backend is read-only.
	getRootStoragePath ()
	Get the root storage path of this backend.
	getScopedFileLocks (array $paths, $type, Status $status, $timeout=0)
	Lock the files at the given storage paths in the backend.
	getScopedLocksForOps (array $ops, Status $status)
	Get an array of scoped locks needed for a batch of file operations.
	getTopDirectoryList (array $params)
	Same as FileBackend::getDirectoryList() except only lists directories that are immediately under the given directory.
	getTopFileList (array $params)
	Same as FileBackend::getFileList() except only lists files that are immediately under the given directory.
	getWikiId ()
	Get the wiki identifier used for this backend (possibly empty).
	hasFeatures ($bitfield)
	Check if the backend medium supports a field of extra features.
	isReadOnly ()
	Check if this backend is read-only.
	lockFiles (array $paths, $type, $timeout=0)
	Lock the files at the given storage paths in the backend.
	move (array $params, array $opts=array())
	Performs a single move operation.
	preloadCache (array $paths)
	Preload persistent file stat cache and property cache into in-process cache.
	preloadFileStat (array $params)
	Preload file stat information (concurrently if possible) into in-process cache.
	prepare (array $params)
	Prepare a storage directory for usage.
	publish (array $params)
	Remove measures to block web access to a storage directory and the container it belongs to.
	quickCopy (array $params)
	Performs a single quick copy operation.
	quickCreate (array $params)
	Performs a single quick create operation.
	quickDelete (array $params)
	Performs a single quick delete operation.
	quickDescribe (array $params)
	Performs a single quick describe operation.
	quickMove (array $params)
	Performs a single quick move operation.
	quickStore (array $params)
	Performs a single quick store operation.
	secure (array $params)
	Take measures to block web access to a storage directory and the container it belongs to.
	store (array $params, array $opts=array())
	Performs a single store operation.
	streamFile (array $params)
	Stream the file at a storage path in the backend.
	unlockFiles (array $paths, $type)
	Unlock the files at the given storage paths in the backend.
Static Public Member Functions
static	extensionFromPath ($path, $case= 'lowercase')
	Get the final extension from a storage or FS path.
static	isPathTraversalFree ($path)
	Check if a relative path has no directory traversals.
static	isStoragePath ($path)
	Check if a given path is a "mwstore://" path.
static	makeContentDisposition ($type, $filename= '')
	Build a Content-Disposition header value per RFC 6266.
static	normalizeStoragePath ($storagePath)
	Normalize a storage path by cleaning up directory separators.
static	parentStoragePath ($storagePath)
	Get the parent storage directory of a storage path.
static	splitStoragePath ($storagePath)
	Split a storage path into a backend name, a container name, and a relative file path.
Public Attributes
const	ATTR_HEADERS = 1
	Bitfield flags for supported features.
const	ATTR_METADATA = 2
const	ATTR_UNICODE_PATHS = 4
Protected Member Functions
	doClean (array $params)
	doOperationsInternal (array $ops, array $opts)
	doPrepare (array $params)
	doPublish (array $params)
	doQuickOperationsInternal (array $ops)
	doSecure (array $params)
	getScopedPHPBehaviorForOps ()
	Enter file operation scope.
Static Protected Member Functions
static	normalizeContainerPath ($path)
	Validate and normalize a relative storage path.
Protected Attributes
int	$concurrency
	How many operations can be done in parallel *.
FileJournal	$fileJournal
	*
LockManager	$lockManager
	*
string	$name
	Unique backend name *.
string	$parallelize
	When to do operations in parallel *.
string	$readOnly
	Read-only explanation message *.
string	$wikiId
	Unique wiki name *.

Detailed Description

Base class for all file backend classes (including multi-write backends).

This class defines the methods as abstract that subclasses must implement. Outside callers can assume that all backends will have these functions.

All "storage paths" are of the format "mwstore://<backend>/<container>/<path>". The "backend" portion is unique name for MediaWiki to refer to a backend, while the "container" portion is a top-level directory of the backend. The "path" portion is a relative path that uses UNIX file system (FS) notation, though any particular backend may not actually be using a local filesystem. Therefore, the relative paths are only virtual.

Backend contents are stored under wiki-specific container names by default. Global (qualified) backends are achieved by configuring the "wiki ID" to a constant. For legacy reasons, the FSFileBackend class allows manually setting the paths of containers to ones that do not respect the "wiki ID".

In key/value (object) stores, containers are the only hierarchy (the rest is emulated). FS-based backends are somewhat more restrictive due to the existence of real directory files; a regular file cannot have the same name as a directory. Other backends with virtual directories may not have this limitation. Callers should store files in such a way that no files and directories are under the same path.

In general, this class allows for callers to access storage through the same interface, without regard to the underlying storage system. However, calling code must follow certain patterns and be aware of certain things to ensure compatibility:

a) Always call prepare() on the parent directory before trying to put a file there; key/value stores only need the container to exist first, but filesystems need all the parent directories to exist first (prepare() is aware of all this)
b) Always call clean() on a directory when it might become empty to avoid empty directory buildup on filesystems; key/value stores never have empty directories, so doing this helps preserve consistency in both cases
c) Likewise, do not rely on the existence of empty directories for anything; calling directoryExists() on a path that prepare() was previously called on will return false for key/value stores if there are no files under that path
d) Never alter the resulting FSFile returned from getLocalReference(), as it could either be a copy of the source file in /tmp or the original source file itself
e) Use a file layout that results in never attempting to store files over directories or directories over files; key/value stores allow this but filesystems do not
f) Use ASCII file names (e.g. base32, IDs, hashes) to avoid Unicode issues in Windows
g) Do not assume that move operations are atomic (difficult with key/value stores)
h) Do not assume that file stat or read operations always have immediate consistency; various methods have a "latest" flag that should always be used if up-to-date information is required (this trades performance for correctness as needed)
i) Do not assume that directory listings have immediate consistency

Methods of subclasses should avoid throwing exceptions at all costs. As a corollary, external dependencies should be kept to a minimum.

Since:: 1.19

Definition at line 85 of file FileBackend.php.

Constructor & Destructor Documentation

FileBackend::__construct ( array $ config )

Create a new backend instance from configuration.

This should only be called from within FileBackendGroup.

Parameters:

array

$config

Parameters include:

name : The unique name of this backend. This should consist of alphanumberic, '-', and '_' characters. This name should not be changed after use (e.g. with journaling). Note that the name is *not* used in actual container names.
wikiId : Prefix to container names that is unique to this backend. It should only consist of alphanumberic, '-', and '_' characters. This ID is what avoids collisions if multiple logical backends use the same storage system, so this should be set carefully.
lockManager : LockManager object to use for any file locking. If not provided, then no file locking will be enforced.
fileJournal : FileJournal object to use for logging changes to files. If not provided, then change journaling will be disabled.
readOnly : Write operations are disallowed if this is a non-empty string. It should be an explanation for the backend being read-only.
parallelize : When to do file operations in parallel (when possible). Allowed values are "implicit", "explicit" and "off".
concurrency : How many file operations can be done in parallel.

Exceptions:

FileBackendException

Reimplemented in SwiftFileBackend, FileBackendMultiWrite, FileBackendStore, and FSFileBackend.

Definition at line 129 of file FileBackend.php.

Member Function Documentation

FileBackend::clean ( array $ params ) [final]

Delete a storage directory if it is empty.

Backends using key/value stores may do nothing unless the directory is that of an empty container, in which case it will be deleted.

Parameters:

array

$params

Parameters include:

dir : storage directory
recursive : recursively delete empty subdirectories first (since 1.20)
bypassReadOnly : allow writes in read-only mode (since 1.20)

Returns:: Status

Definition at line 832 of file FileBackend.php.

FileBackend::clearCache ( array $ paths = null ) [abstract]

Invalidate any in-process file stat and property cache.

If $paths is given, then only the cache for those files will be cleared.

See also:: FileBackend::getFileStat()

Parameters:

array $paths Storage paths (optional)

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::concatenate ( array $ params ) [abstract]

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.

Parameters:

array

$params

Operation parameters, include:

srcs : ordered source storage paths (e.g. chunk1, chunk2, ...)
dst : file system path to 0-byte temp file
parallelize : try to do operations in parallel when possible

Returns:: Status

Reimplemented in FileBackendMultiWrite, and FileBackendStore.

FileBackend::copy	(	array $	params,
		array $	opts = `array()`
	)		`[final]`

Performs a single copy operation.

This sets $params['op'] to 'copy' and passes it to doOperation().

See also:: FileBackend::doOperation()

Parameters:

array	$params	Operation parameters
array	$opts	Operation options

Returns:: Status

Definition at line 438 of file FileBackend.php.

FileBackend::create	(	array $	params,
		array $	opts = `array()`
	)		`[final]`

Performs a single create operation.

This sets $params['op'] to 'create' and passes it to doOperation().

See also:: FileBackend::doOperation()

Parameters:

array	$params	Operation parameters
array	$opts	Operation options

Returns:: Status

Definition at line 410 of file FileBackend.php.

FileBackend::delete	(	array $	params,
		array $	opts = `array()`
	)		`[final]`

Performs a single delete operation.

This sets $params['op'] to 'delete' and passes it to doOperation().

See also:: FileBackend::doOperation()

Parameters:

array	$params	Operation parameters
array	$opts	Operation options

Returns:: Status

Definition at line 466 of file FileBackend.php.

FileBackend::describe	(	array $	params,
		array $	opts = `array()`
	)		`[final]`

Performs a single describe operation.

This sets $params['op'] to 'describe' and passes it to doOperation().

See also:: FileBackend::doOperation()

Parameters:

array	$params	Operation parameters
array	$opts	Operation options

Returns:: Status

Since:: 1.21

Definition at line 481 of file FileBackend.php.

FileBackend::directoryExists ( array $ params ) [abstract]

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.

Parameters:

array

$params

Parameters include:

dir : storage directory

Returns:: bool|null Returns null on failure

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::doClean ( array $ params ) [abstract, protected]

See also:: FileBackend::clean()

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::doOperation	(	array $	op,
		array $	opts = `array()`
	)		`[final]`

Same as doOperations() except it takes a single operation.

If you are doing a batch of operations that should either all succeed or all fail, then use that function instead.

See also:: FileBackend::doOperations()

Parameters:

array	$op	Operation
array	$opts	Operation options

Returns:: Status

Definition at line 396 of file FileBackend.php.

FileBackend::doOperations	(	array $	ops,
		array $	opts = `array()`
	)		`[final]`

This is the main entry point into the backend for write operations.

Callers supply an ordered list of operations to perform as a transaction. Files will be locked, the stat cache cleared, and then the operations attempted. If any serious errors occur, all attempted operations will be rolled back.

$ops is an array of arrays. The outer array holds a list of operations. Each inner array is a set of key value pairs that specify an operation.

Supported operations and their parameters. The supported actions are:

create
store
copy
move
delete
describe (since 1.21)
null

a) Create a new file in storage with the contents of a string

     array(
         'op'                  => 'create',
         'dst'                 => <storage path>,
         'content'             => <string of new file contents>,
         'overwrite'           => <boolean>,
         'overwriteSame'       => <boolean>,
         'headers'             => <HTTP header name/value map> # since 1.21
     );

b) Copy a file system file into storage

     array(
         'op'                  => 'store',
         'src'                 => <file system path>,
         'dst'                 => <storage path>,
         'overwrite'           => <boolean>,
         'overwriteSame'       => <boolean>,
         'headers'             => <HTTP header name/value map> # since 1.21
     )

c) Copy a file within storage

     array(
         'op'                  => 'copy',
         'src'                 => <storage path>,
         'dst'                 => <storage path>,
         'overwrite'           => <boolean>,
         'overwriteSame'       => <boolean>,
         'ignoreMissingSource' => <boolean>, # since 1.21
         'headers'             => <HTTP header name/value map> # since 1.21
     )

d) Move a file within storage

     array(
         'op'                  => 'move',
         'src'                 => <storage path>,
         'dst'                 => <storage path>,
         'overwrite'           => <boolean>,
         'overwriteSame'       => <boolean>,
         'ignoreMissingSource' => <boolean>, # since 1.21
         'headers'             => <HTTP header name/value map> # since 1.21
     )

e) Delete a file within storage

     array(
         'op'                  => 'delete',
         'src'                 => <storage path>,
         'ignoreMissingSource' => <boolean>
     )

f) Update metadata for a file within storage

     array(
         'op'                  => 'describe',
         'src'                 => <storage path>,
         'headers'             => <HTTP header name/value map>
     )

g) Do nothing (no-op)

     array(
         'op'                  => 'null',
     )

Boolean flags for operations (operation-specific):

ignoreMissingSource : The operation will simply succeed and do nothing if the source file does not exist.
overwrite : Any destination file will be overwritten.
overwriteSame : If a file already exists at the destination with the same contents, then do nothing to the destination file instead of giving an error. This does not compare headers. This option is ignored if 'overwrite' is already provided.
headers : If supplied, the result of merging these headers with any existing source file headers (replacing conflicting ones) will be set as the destination file headers. Headers are deleted if their value is set to the empty string. When a file has headers they are included in responses to GET and HEAD requests to the backing store for that file. Header values should be no larger than 255 bytes, except for Content-Disposition. The system might ignore or truncate any headers that are too long to store (exact limits will vary). Backends that don't support metadata ignore this. (since 1.21)

$opts is an associative of boolean flags, including:

force : Operation precondition errors no longer trigger an abort. Any remaining operations are still attempted. Unexpected failures may still cause remaining operations to be aborted.
nonLocking : No locks are acquired for the operations. This can increase performance for non-critical writes. This has no effect unless the 'force' flag is set.
nonJournaled : Don't log this operation batch in the file journal. This limits the ability of recovery scripts.
parallelize : Try to do operations in parallel when possible.
bypassReadOnly : Allow writes in read-only mode. (since 1.20)
preserveCache : Don't clear the process cache before checking files. This should only be used if all entries in the process cache were added after the files were already locked. (since 1.20)

Remarks:: Remarks on locking: File system paths given to operations should refer to files that are already locked or otherwise safe from modification from other processes. Normally these files will be new temp files, which should be adequate.

Return value:

This returns a Status, which contains all warnings and fatals that occurred during the operation. The 'failCount', 'successCount', and 'success' members will reflect each operation attempted.

The status will be "OK" unless:

a) unexpected operation errors occurred (network partitions, disk full...)
b) significant operation errors occurred and 'force' was not set

Parameters:

array	$ops	List of operations to execute in order
array	$opts	Batch operation options

Returns:: Status

Definition at line 361 of file FileBackend.php.

Referenced by FileRepo\storeBatch().

FileBackend::doOperationsInternal	(	array $	ops,
		array $	opts
	)		`[abstract, protected]`

See also:: FileBackend::doOperations()

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::doPrepare ( array $ params ) [abstract, protected]

See also:: FileBackend::prepare()

Reimplemented in FileBackendMultiWrite, and FileBackendStore.

FileBackend::doPublish ( array $ params ) [abstract, protected]

See also:: FileBackend::publish()

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::doQuickOperation ( array $ op ) [final]

Same as doQuickOperations() except it takes a single operation.

If you are doing a batch of operations, then use that function instead.

See also:: FileBackend::doQuickOperations()

Parameters:

array $op Operation

Returns:: Status

Since:: 1.20

Definition at line 628 of file FileBackend.php.

FileBackend::doQuickOperations	(	array $	ops,
		array $	opts = `array()`
	)		`[final]`

Perform a set of independent file operations on some files.

This does no locking, nor journaling, and possibly no stat calls. Any destination files that already exist will be overwritten. This should *only* be used on non-original files, like cache files.

Supported operations and their parameters:

create
store
copy
move
delete
describe (since 1.21)
null

a) Create a new file in storage with the contents of a string

     array(
         'op'                  => 'create',
         'dst'                 => <storage path>,
         'content'             => <string of new file contents>,
         'headers'             => <HTTP header name/value map> # since 1.21
     )

b) Copy a file system file into storage

     array(
         'op'                  => 'store',
         'src'                 => <file system path>,
         'dst'                 => <storage path>,
         'headers'             => <HTTP header name/value map> # since 1.21
     )

c) Copy a file within storage

     array(
         'op'                  => 'copy',
         'src'                 => <storage path>,
         'dst'                 => <storage path>,
         'ignoreMissingSource' => <boolean>, # since 1.21
         'headers'             => <HTTP header name/value map> # since 1.21
     )

d) Move a file within storage

     array(
         'op'                  => 'move',
         'src'                 => <storage path>,
         'dst'                 => <storage path>,
         'ignoreMissingSource' => <boolean>, # since 1.21
         'headers'             => <HTTP header name/value map> # since 1.21
     )

e) Delete a file within storage

     array(
         'op'                  => 'delete',
         'src'                 => <storage path>,
         'ignoreMissingSource' => <boolean>
     )

f) Update metadata for a file within storage

     array(
         'op'                  => 'describe',
         'src'                 => <storage path>,
         'headers'             => <HTTP header name/value map>
     )

g) Do nothing (no-op)

     array(
         'op'                  => 'null',
     )

Boolean flags for operations (operation-specific):

ignoreMissingSource : The operation will simply succeed and do nothing if the source file does not exist.
headers : If supplied with a header name/value map, the backend will reply with these headers when GETs/HEADs of the destination file are made. Header values should be smaller than 256 bytes. Content-Disposition headers can be longer, though the system might ignore or truncate ones that are too long to store. Existing headers will remain, but these will replace any conflicting previous headers, and headers will be removed if they are set to an empty string. Backends that don't support metadata ignore this. (since 1.21)

$opts is an associative of boolean flags, including:

bypassReadOnly : Allow writes in read-only mode (since 1.20)

Return value:: This returns a Status, which contains all warnings and fatals that occurred during the operation. The 'failCount', 'successCount', and 'success' members will reflect each operation attempted for the given files. The status will be considered "OK" as long as no fatal errors occurred.

Parameters:

array	$ops	Set of operations to execute
array	$opts	Batch operation options

Returns:: Status

Since:: 1.20

Definition at line 595 of file FileBackend.php.

Referenced by SyncFileBackend\syncFileBatch().

FileBackend::doQuickOperationsInternal ( array $ ops ) [abstract, protected]

See also:: FileBackend::doQuickOperations()

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::doSecure ( array $ params ) [abstract, protected]

See also:: FileBackend::secure()

Reimplemented in FileBackendMultiWrite, and FileBackendStore.

static FileBackend::extensionFromPath	(	$	path,
		$	case = `'lowercase'`
	)		`[static, final]`

Get the final extension from a storage or FS path.

Parameters:

string	$path
string	$case	One of (rawcase, uppercase, lowercase) (since 1.24)

Returns:: string

Definition at line 1397 of file FileBackend.php.

Referenced by MemoryFileBackend\doGetLocalCopyMulti(), and FileRepo\isLocal().

FileBackend::fileExists ( array $ params ) [abstract]

Check if a file exists at a storage path in the backend.

This returns false if only a directory exists at the path.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: bool|null Returns null on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

Referenced by SyncFileBackend\syncFileBatch().

FileBackend::getContainerStoragePath ( $ container ) [final]

Get the storage path for the given container for this backend.

Parameters:

string $container Container name

Returns:: string Storage path

Since:: 1.21

Definition at line 1306 of file FileBackend.php.

FileBackend::getDirectoryList ( array $ params ) [abstract]

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).

Parameters:

array

$params

Parameters include:

dir : storage directory
topOnly : only return direct child dirs of the directory

Returns:: Traversable|array|null Returns null on failure

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFeatures ( )

Get the a bitfield of extra features supported by the backend medium.

Returns:: int Bitfield of FileBackend::ATTR_* flags

Since:: 1.23

Reimplemented in FileBackendMultiWrite, SwiftFileBackend, and FSFileBackend.

Definition at line 200 of file FileBackend.php.

References ATTR_UNICODE_PATHS.

FileBackend::getFileContents ( array $ params ) [final]

Get the contents of a file at a storage path in the backend.

This should be avoided for potentially large files.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: string|bool Returns false on failure

Definition at line 893 of file FileBackend.php.

FileBackend::getFileContentsMulti ( array $ params ) [abstract]

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.

See also:: FileBackend::getFileContents()

Parameters:

array

$params

Parameters include:

srcs : list of source storage paths
latest : use the latest available data
parallelize : try to do operations in parallel when possible

Returns:: array Map of (path name => string or false on failure)

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFileHttpUrl ( array $ params ) [abstract]

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.

Parameters:

array

$params

Parameters include:

src : source storage path
ttl : lifetime (seconds) if pre-authenticated; default is 1 day

Returns:: string|null

Since:: 1.21

Reimplemented in SwiftFileBackend, FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFileList ( array $ params ) [abstract]

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).

Parameters:

array

$params

Parameters include:

dir : storage directory
topOnly : only return direct child files of the directory (since 1.20)
adviseStat : set to true if stat requests will be made on the files (since 1.22)

Returns:: Traversable|array|null Returns null on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFileProps ( array $ params ) [abstract]

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.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: array Returns FSFile::placeholderProps() on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFileSha1Base36 ( array $ params ) [abstract]

Get a SHA-1 hash of the file at a storage path in the backend.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: string|bool Hash string or false on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

Referenced by SyncFileBackend\filesAreSame().

FileBackend::getFileSize ( array $ params ) [abstract]

Get the size (bytes) of a file at a storage path in the backend.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: int|bool Returns false on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

Referenced by SyncFileBackend\filesAreSame().

FileBackend::getFileStat ( array $ params ) [abstract]

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:

mtime : the last-modified timestamp (TS_MW)
size : the file size (bytes) Additional values may be included for internal use only.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: array|bool|null Returns null on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFileTimestamp ( array $ params ) [abstract]

Get the last-modified timestamp of the file at a storage path.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: string|bool TS_MW timestamp or false on failure

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getFileXAttributes ( array $ params ) [abstract]

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:

headers : map of HTTP headers used for GET/HEAD requests (name => value)
metadata : map of file metadata (name => value) Metadata keys and headers names will be returned in all lower-case. Additional values may be included for internal use only.

Use FileBackend::hasFeatures() to check how well this is supported.

Parameters:

array

$params

$params include:

src : source storage path
latest : use the latest available data

Returns:: array|bool Returns false on failure

Since:: 1.23

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getJournal ( ) [final]

Get the file journal object for this backend.

Returns:: FileJournal

Definition at line 1315 of file FileBackend.php.

Referenced by SyncFileBackend\syncBackends().

FileBackend::getLocalCopy ( array $ params ) [final]

Get a local copy on disk of the file at a storage path in the backend.

The temporary copy will have the same file extension as the source. Temporary files may be purged when the file object falls out of scope.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: TempFSFile|null Returns null on failure

Definition at line 1048 of file FileBackend.php.

FileBackend::getLocalCopyMulti ( array $ params ) [abstract]

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.

See also:: FileBackend::getLocalCopy()

Parameters:

array

$params

Parameters include:

srcs : list of source storage paths
latest : use the latest available data
parallelize : try to do operations in parallel when possible

Returns:: array Map of (path name => TempFSFile or null on failure)

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getLocalReference ( array $ params ) [final]

Returns a file system file, identical to the file at a storage path.

The file returned is either:

a) A local copy of the file at a storage path in the backend. The temporary copy will have the same extension as the source.
b) An original of the file at a storage path in the backend. Temporary files may be purged when the file object falls out of scope.

Write operations should *never* be done on this file as some backends may do internal tracking or may be instances of FileBackendMultiWrite. In that later case, there are copies of the file that must stay in sync. Additionally, further calls to this function may return the same file.

Parameters:

array

$params

Parameters include:

src : source storage path
latest : use the latest available data

Returns:: FSFile|null Returns null on failure

Definition at line 1015 of file FileBackend.php.

Referenced by SyncFileBackend\syncFileBatch().

FileBackend::getLocalReferenceMulti ( array $ params ) [abstract]

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.

See also:: FileBackend::getLocalReference()

Parameters:

array

$params

Parameters include:

srcs : list of source storage paths
latest : use the latest available data
parallelize : try to do operations in parallel when possible

Returns:: array Map of (path name => FSFile or null on failure)

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getName ( ) [final]

Get the unique backend name.

We may have multiple different backends of the same type. For example, we can have two Swift backends using different proxies.

Returns:: string

Definition at line 161 of file FileBackend.php.

Referenced by TestFileOpPerformance\doPerfTest(), SyncFileBackend\replaceNamePaths(), and SyncFileBackend\syncFileBatch().

FileBackend::getReadOnlyReason ( ) [final]

Get an explanatory message if this backend is read-only.

Returns:: string|bool Returns false if the backend is not read-only

Definition at line 190 of file FileBackend.php.

FileBackend::getRootStoragePath ( ) [final]

Get the root storage path of this backend.

All container paths are "subdirectories" of this path.

Returns:: string Storage path

Since:: 1.20

Definition at line 1295 of file FileBackend.php.

FileBackend::getScopedFileLocks	(	array $	paths,
		$	type,
		Status $	status,
		$	timeout = `0`
	)		`[final]`

Lock the files at the given storage paths in the backend.

This will either lock all the files or none (on failure). On failure, the status object will be updated with errors.

Once the return value goes out scope, the locks will be released and the status updated. Unlock fatals will not change the status "OK" value.

See also:: ScopedLock::factory()

Parameters:

array	$paths	List of storage paths or map of lock types to path lists
int \| string	$type	LockManager::LOCK_* constant or "mixed"
Status	$status	Status to update on lock/unlock
int	$timeout	Timeout in seconds (0 means non-blocking) (since 1.24)

Returns:: ScopedLock|null Returns null on failure

Definition at line 1258 of file FileBackend.php.

Referenced by SyncFileBackend\syncFileBatch().

FileBackend::getScopedLocksForOps	(	array $	ops,
		Status $	status
	)		`[abstract]`

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.

See also:: FileBackend::doOperations()

Parameters:

array	$ops	List of file operations to FileBackend::doOperations()
Status	$status	Status to update on lock/unlock

Returns:: array List of ScopedFileLocks or null values

Since:: 1.20

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::getScopedPHPBehaviorForOps ( ) [final, protected]

Enter file operation scope.

This just makes PHP ignore user aborts/disconnects until the return value leaves scope. This returns null and does nothing in CLI mode.

Returns:: ScopedCallback|null

Definition at line 852 of file FileBackend.php.

FileBackend::getTopDirectoryList ( array $ params ) [final]

Same as FileBackend::getDirectoryList() except only lists directories that are immediately under the given directory.

Storage backends with eventual consistency might return stale data.

Failures during iteration can result in FileBackendError exceptions (since 1.22).

Parameters:

array

$params

Parameters include:

dir : storage directory

Returns:: Traversable|array|null Returns null on failure

Since:: 1.20

Definition at line 1136 of file FileBackend.php.

FileBackend::getTopFileList ( array $ params ) [final]

Same as FileBackend::getFileList() except only lists files that are immediately under the given directory.

Storage backends with eventual consistency might return stale data.

Failures during iteration can result in FileBackendError exceptions (since 1.22).

Parameters:

array

$params

Parameters include:

dir : storage directory
adviseStat : set to true if stat requests will be made on the files (since 1.22)

Returns:: Traversable|array|null Returns null on failure

Since:: 1.20

Definition at line 1174 of file FileBackend.php.

FileBackend::getWikiId ( ) [final]

Get the wiki identifier used for this backend (possibly empty).

Note that this might *not* be in the same format as wfWikiID().

Returns:: string

Since:: 1.20

Definition at line 172 of file FileBackend.php.

FileBackend::hasFeatures ( $ bitfield ) [final]

Check if the backend medium supports a field of extra features.

Parameters:

int $bitfield Bitfield of FileBackend::ATTR_* flags

Returns:: bool

Since:: 1.23

Definition at line 211 of file FileBackend.php.

static FileBackend::isPathTraversalFree ( $ path ) [static, final]

Check if a relative path has no directory traversals.

Parameters:

string $path

Returns:: bool

Since:: 1.20

Definition at line 1417 of file FileBackend.php.

FileBackend::isReadOnly ( ) [final]

Check if this backend is read-only.

Returns:: bool

Definition at line 181 of file FileBackend.php.

static FileBackend::isStoragePath ( $ path ) [static, final]

Check if a given path is a "mwstore://" path.

This does not do any further validation or any existence checks.

Parameters:

string $path

Returns:: bool

Definition at line 1326 of file FileBackend.php.

Referenced by UploadBase\initializePathInfo(), FileRepo\storeBatch(), StreamFile\stream(), and wfMkdirParents().

FileBackend::lockFiles	(	array $	paths,
		$	type,
		$	timeout = `0`
	)		`[final]`

Lock the files at the given storage paths in the backend.

This will either lock all the files or none (on failure).

Callers should consider using getScopedFileLocks() instead.

Parameters:

array	$paths	Storage paths
int	$type	LockManager::LOCK_* constant
int	$timeout	Timeout in seconds (0 means non-blocking) (since 1.24)

Returns:: Status

Definition at line 1223 of file FileBackend.php.

static FileBackend::makeContentDisposition	(	$	type,
		$	filename = `''`
	)		`[static, final]`

Build a Content-Disposition header value per RFC 6266.

Parameters:

string	$type	One of (attachment, inline)
string	$filename	Suggested file name (should not contain slashes)

Exceptions:

FileBackendError

Returns:: string

Since:: 1.20

Definition at line 1430 of file FileBackend.php.

FileBackend::move	(	array $	params,
		array $	opts = `array()`
	)		`[final]`

Performs a single move operation.

This sets $params['op'] to 'move' and passes it to doOperation().

See also:: FileBackend::doOperation()

Parameters:

array	$params	Operation parameters
array	$opts	Operation options

Returns:: Status

Definition at line 452 of file FileBackend.php.

static FileBackend::normalizeContainerPath ( $ path ) [static, final, protected]

Validate and normalize a relative storage path.

Null is returned if the path involves directory traversal. Traversal is insecure for FS backends and broken for others.

This uses the same traversal protection as Title::secureAndSplit().

Parameters:

string $path Storage path relative to a container

Returns:: string|null

Definition at line 1456 of file FileBackend.php.

static FileBackend::normalizeStoragePath ( $ storagePath ) [static, final]

Normalize a storage path by cleaning up directory separators.

Returns null if the path is not of the format of a valid storage path.

Parameters:

string $storagePath

Returns:: string|null

Definition at line 1361 of file FileBackend.php.

static FileBackend::parentStoragePath ( $ storagePath ) [static, final]

Get the parent storage directory of a storage path.

This returns a path like "mwstore://backend/container", "mwstore://backend/container/...", or null if there is no parent.

Parameters:

string $storagePath

Returns:: string|null

Definition at line 1383 of file FileBackend.php.

Referenced by StoreBatchTest\tearDown().

FileBackend::preloadCache ( array $ paths ) [abstract]

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.

See also:: FileBackend::getFileStat()

Parameters:

array $paths Storage paths

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::preloadFileStat ( array $ params ) [abstract]

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.

See also:: FileBackend::getFileStat()

Parameters:

array

$params

Parameters include:

srcs : list of source storage paths
latest : use the latest available data

Returns:: bool All requests proceeded without I/O errors (since 1.24)

Since:: 1.23

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

Referenced by SyncFileBackend\syncFileBatch().

FileBackend::prepare ( array $ params ) [final]

Prepare a storage directory for usage.

This will create any required containers and parent directories. Backends using key/value stores only need to create the container.

The 'noAccess' and 'noListing' parameters works the same as in secure(), except they are only applied *if* the directory/container had to be created. These flags should always be set for directories that have private files. However, setting them is not guaranteed to actually do anything. Additional server configuration may be needed to achieve the desired effect.

Parameters:

array

$params

Parameters include:

dir : storage directory
noAccess : try to deny file access (since 1.20)
noListing : try to deny file listing (since 1.20)
bypassReadOnly : allow writes in read-only mode (since 1.20)

Returns:: Status

Definition at line 748 of file FileBackend.php.

Referenced by TestFileOpPerformance\doPerfTest(), and SyncFileBackend\syncFileBatch().

FileBackend::publish ( array $ params ) [final]

Remove measures to block web access to a storage directory and the container it belongs to.

FS backends might remove .htaccess files whereas key/value store backends might grant container access to the storage user representing end-users in web requests. This essentially can undo the result of secure() calls.

This is not guaranteed to actually make files or listings publically viewable. Additional server configuration may be needed to achieve the desired effect.

Parameters:

array

$params

Parameters include:

dir : storage directory
access : try to allow file access
listing : try to allow file listing
bypassReadOnly : allow writes in read-only mode (since 1.20)

Returns:: Status

Since:: 1.20

Definition at line 808 of file FileBackend.php.

FileBackend::quickCopy ( array $ params ) [final]

Performs a single quick copy operation.

This sets $params['op'] to 'copy' and passes it to doQuickOperation().

See also:: FileBackend::doQuickOperation()

Parameters:

array $params Operation parameters

Returns:: Status

Since:: 1.20

Definition at line 670 of file FileBackend.php.

FileBackend::quickCreate ( array $ params ) [final]

Performs a single quick create operation.

This sets $params['op'] to 'create' and passes it to doQuickOperation().

See also:: FileBackend::doQuickOperation()

Parameters:

array $params Operation parameters

Returns:: Status

Since:: 1.20

Definition at line 642 of file FileBackend.php.

FileBackend::quickDelete ( array $ params ) [final]

Performs a single quick delete operation.

This sets $params['op'] to 'delete' and passes it to doQuickOperation().

See also:: FileBackend::doQuickOperation()

Parameters:

array $params Operation parameters

Returns:: Status

Since:: 1.20

Definition at line 698 of file FileBackend.php.

FileBackend::quickDescribe ( array $ params ) [final]

Performs a single quick describe operation.

This sets $params['op'] to 'describe' and passes it to doQuickOperation().

See also:: FileBackend::doQuickOperation()

Parameters:

array $params Operation parameters

Returns:: Status

Since:: 1.21

Definition at line 712 of file FileBackend.php.

FileBackend::quickMove ( array $ params ) [final]

Performs a single quick move operation.

This sets $params['op'] to 'move' and passes it to doQuickOperation().

See also:: FileBackend::doQuickOperation()

Parameters:

array $params Operation parameters

Returns:: Status

Since:: 1.20

Definition at line 684 of file FileBackend.php.

FileBackend::quickStore ( array $ params ) [final]

Performs a single quick store operation.

This sets $params['op'] to 'store' and passes it to doQuickOperation().

See also:: FileBackend::doQuickOperation()

Parameters:

array $params Operation parameters

Returns:: Status

Since:: 1.20

Definition at line 656 of file FileBackend.php.

FileBackend::secure ( array $ params ) [final]

Take measures to block web access to a storage directory and the container it belongs to.

FS backends might add .htaccess files whereas key/value store backends might revoke container access to the storage user representing end-users in web requests.

This is not guaranteed to actually make files or listings publically hidden. Additional server configuration may be needed to achieve the desired effect.

Parameters:

array

$params

Parameters include:

dir : storage directory
noAccess : try to deny file access
noListing : try to deny file listing
bypassReadOnly : allow writes in read-only mode (since 1.20)

Returns:: Status

Definition at line 777 of file FileBackend.php.

static FileBackend::splitStoragePath ( $ storagePath ) [static, final]

Split a storage path into a backend name, a container name, and a relative file path.

The relative path may be the empty string. This does not do any path normalization or traversal checks.

Parameters:

string $storagePath

Returns:: array (backend, container, rel object) or (null, null, null)

Definition at line 1338 of file FileBackend.php.

Referenced by FileBackendMultiWrite\doPrepare().

FileBackend::store	(	array $	params,
		array $	opts = `array()`
	)		`[final]`

Performs a single store operation.

This sets $params['op'] to 'store' and passes it to doOperation().

See also:: FileBackend::doOperation()

Parameters:

array	$params	Operation parameters
array	$opts	Operation options

Returns:: Status

Definition at line 424 of file FileBackend.php.

FileBackend::streamFile ( array $ params ) [abstract]

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.

Parameters:

array

$params

Parameters include:

src : source storage path
headers : list of additional HTTP headers to send on success
latest : use the latest available data

Returns:: Status

Reimplemented in FileBackendStore, and FileBackendMultiWrite.

FileBackend::unlockFiles	(	array $	paths,
		$	type
	)		`[final]`

Unlock the files at the given storage paths in the backend.

Parameters:

array	$paths	Storage paths
int	$type	LockManager::LOCK_* constant

Returns:: Status

Definition at line 1236 of file FileBackend.php.

Member Data Documentation

int FileBackend::$concurrency [protected]

How many operations can be done in parallel *.

Definition at line 94 of file FileBackend.php.

FileJournal FileBackend::$fileJournal [protected]

*

Definition at line 98 of file FileBackend.php.

LockManager FileBackend::$lockManager [protected]

*

Definition at line 96 of file FileBackend.php.

string FileBackend::$name [protected]

Unique backend name *.

Definition at line 86 of file FileBackend.php.

string FileBackend::$parallelize [protected]

When to do operations in parallel *.

Definition at line 92 of file FileBackend.php.

string FileBackend::$readOnly [protected]

Read-only explanation message *.

Definition at line 90 of file FileBackend.php.

string FileBackend::$wikiId [protected]

Unique wiki name *.

Definition at line 88 of file FileBackend.php.

const FileBackend::ATTR_HEADERS = 1

Bitfield flags for supported features.

Definition at line 101 of file FileBackend.php.

const FileBackend::ATTR_METADATA = 2

Definition at line 102 of file FileBackend.php.

const FileBackend::ATTR_UNICODE_PATHS = 4

Definition at line 103 of file FileBackend.php.

Referenced by getFeatures().

The documentation for this class was generated from the following file:

includes/filebackend/FileBackend.php

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation