3 * @defgroup FileBackend File backend
5 * File backend is used to interact with file storage systems,
6 * such as the local file system, NFS, or cloud storage systems.
10 * Base class for all file backends.
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
25 * http://www.gnu.org/copyleft/gpl.html
28 * @ingroup FileBackend
30 use MediaWiki\FileBackend\FSFile\TempFSFileFactory
;
31 use Psr\Log\LoggerAwareInterface
;
32 use Psr\Log\LoggerInterface
;
33 use Wikimedia\ScopedCallback
;
34 use Psr\Log\NullLogger
;
37 * @brief Base class for all file backend classes (including multi-write backends).
39 * This class defines the methods as abstract that subclasses must implement.
40 * Outside callers can assume that all backends will have these functions.
42 * All "storage paths" are of the format "mwstore://<backend>/<container>/<path>".
43 * The "backend" portion is unique name for the application to refer to a backend, while
44 * the "container" portion is a top-level directory of the backend. The "path" portion
45 * is a relative path that uses UNIX file system (FS) notation, though any particular
46 * backend may not actually be using a local filesystem. Therefore, the relative paths
49 * Backend contents are stored under "domain"-specific container names by default.
50 * A domain is simply a logical umbrella for entities, such as those belonging to a certain
51 * application or portion of a website, for example. A domain can be local or global.
52 * Global (qualified) backends are achieved by configuring the "domain ID" to a constant.
53 * Global domains are simpler, but local domains can be used by choosing a domain ID based on
54 * the current context, such as which language of a website is being used.
56 * For legacy reasons, the FSFileBackend class allows manually setting the paths of
57 * containers to ones that do not respect the "domain ID".
59 * In key/value (object) stores, containers are the only hierarchy (the rest is emulated).
60 * FS-based backends are somewhat more restrictive due to the existence of real
61 * directory files; a regular file cannot have the same name as a directory. Other
62 * backends with virtual directories may not have this limitation. Callers should
63 * store files in such a way that no files and directories are under the same path.
65 * In general, this class allows for callers to access storage through the same
66 * interface, without regard to the underlying storage system. However, calling code
67 * must follow certain patterns and be aware of certain things to ensure compatibility:
68 * - a) Always call prepare() on the parent directory before trying to put a file there;
69 * key/value stores only need the container to exist first, but filesystems need
70 * all the parent directories to exist first (prepare() is aware of all this)
71 * - b) Always call clean() on a directory when it might become empty to avoid empty
72 * directory buildup on filesystems; key/value stores never have empty directories,
73 * so doing this helps preserve consistency in both cases
74 * - c) Likewise, do not rely on the existence of empty directories for anything;
75 * calling directoryExists() on a path that prepare() was previously called on
76 * will return false for key/value stores if there are no files under that path
77 * - d) Never alter the resulting FSFile returned from getLocalReference(), as it could
78 * either be a copy of the source file in /tmp or the original source file itself
79 * - e) Use a file layout that results in never attempting to store files over directories
80 * or directories over files; key/value stores allow this but filesystems do not
81 * - f) Use ASCII file names (e.g. base32, IDs, hashes) to avoid Unicode issues in Windows
82 * - g) Do not assume that move operations are atomic (difficult with key/value stores)
83 * - h) Do not assume that file stat or read operations always have immediate consistency;
84 * various methods have a "latest" flag that should always be used if up-to-date
85 * information is required (this trades performance for correctness as needed)
86 * - i) Do not assume that directory listings have immediate consistency
88 * Methods of subclasses should avoid throwing exceptions at all costs.
89 * As a corollary, external dependencies should be kept to a minimum.
91 * @ingroup FileBackend
94 abstract class FileBackend
implements LoggerAwareInterface
{
95 /** @var string Unique backend name */
98 /** @var string Unique domain name */
101 /** @var string Read-only explanation message */
104 /** @var string When to do operations in parallel */
105 protected $parallelize;
107 /** @var int How many operations can be done in parallel */
108 protected $concurrency;
110 /** @var TempFSFileFactory */
111 protected $tmpFileFactory;
113 /** @var LockManager */
114 protected $lockManager;
115 /** @var FileJournal */
116 protected $fileJournal;
117 /** @var LoggerInterface */
119 /** @var callable|null */
123 protected $obResetFunc;
125 protected $streamMimeFunc;
127 protected $statusWrapper;
129 /** Bitfield flags for supported features */
130 const ATTR_HEADERS
= 1; // files can be tagged with standard HTTP headers
131 const ATTR_METADATA
= 2; // files can be stored with metadata key/values
132 const ATTR_UNICODE_PATHS
= 4; // files can have Unicode paths (not just ASCII)
134 /** @var null Idiom for "could not determine due to I/O errors" */
135 const UNKNOWN
= null;
138 * Create a new backend instance from configuration.
139 * This should only be called from within FileBackendGroup.
141 * @param array $config Parameters include:
142 * - name : The unique name of this backend.
143 * This should consist of alphanumberic, '-', and '_' characters.
144 * This name should not be changed after use (e.g. with journaling).
145 * Note that the name is *not* used in actual container names.
146 * - domainId : Prefix to container names that is unique to this backend.
147 * It should only consist of alphanumberic, '-', and '_' characters.
148 * This ID is what avoids collisions if multiple logical backends
149 * use the same storage system, so this should be set carefully.
150 * - lockManager : LockManager object to use for any file locking.
151 * If not provided, then no file locking will be enforced.
152 * - fileJournal : FileJournal object to use for logging changes to files.
153 * If not provided, then change journaling will be disabled.
154 * - readOnly : Write operations are disallowed if this is a non-empty string.
155 * It should be an explanation for the backend being read-only.
156 * - parallelize : When to do file operations in parallel (when possible).
157 * Allowed values are "implicit", "explicit" and "off".
158 * - concurrency : How many file operations can be done in parallel.
159 * - tmpDirectory : Directory to use for temporary files.
160 * - tmpFileFactory : Optional TempFSFileFactory object. Only has an effect if tmpDirectory is
161 * not set. If both are unset or null, then the backend will try to discover a usable
162 * temporary directory.
163 * - obResetFunc : alternative callback to clear the output buffer
164 * - streamMimeFunc : alternative method to determine the content type from the path
165 * - logger : Optional PSR logger object.
166 * - profiler : Optional callback that takes a section name argument and returns
167 * a ScopedCallback instance that ends the profile section in its destructor.
168 * @throws InvalidArgumentException
170 public function __construct( array $config ) {
171 $this->name
= $config['name'];
172 $this->domainId
= $config['domainId'] // e.g. "my_wiki-en_"
173 ??
$config['wikiId']; // b/c alias
174 if ( !preg_match( '!^[a-zA-Z0-9-_]{1,255}$!', $this->name
) ) {
175 throw new InvalidArgumentException( "Backend name '{$this->name}' is invalid." );
176 } elseif ( !is_string( $this->domainId
) ) {
177 throw new InvalidArgumentException(
178 "Backend domain ID not provided for '{$this->name}'." );
180 $this->lockManager
= $config['lockManager'] ??
new NullLockManager( [] );
181 $this->fileJournal
= $config['fileJournal']
182 ?? FileJournal
::factory( [ 'class' => NullFileJournal
::class ], $this->name
);
183 $this->readOnly
= isset( $config['readOnly'] )
184 ?
(string)$config['readOnly']
186 $this->parallelize
= isset( $config['parallelize'] )
187 ?
(string)$config['parallelize']
189 $this->concurrency
= isset( $config['concurrency'] )
190 ?
(int)$config['concurrency']
192 $this->obResetFunc
= $config['obResetFunc'] ??
[ $this, 'resetOutputBuffer' ];
193 $this->streamMimeFunc
= $config['streamMimeFunc'] ??
null;
194 $this->statusWrapper
= $config['statusWrapper'] ??
null;
196 $this->profiler
= $config['profiler'] ??
null;
197 if ( !is_callable( $this->profiler
) ) {
198 $this->profiler
= null;
200 $this->logger
= $config['logger'] ??
new NullLogger();
201 $this->statusWrapper
= $config['statusWrapper'] ??
null;
202 // tmpDirectory gets precedence for backward compatibility
203 if ( isset( $config['tmpDirectory'] ) ) {
204 $this->tmpFileFactory
= new TempFSFileFactory( $config['tmpDirectory'] );
206 $this->tmpFileFactory
= $config['tmpFileFactory'] ??
new TempFSFileFactory();
210 public function setLogger( LoggerInterface
$logger ) {
211 $this->logger
= $logger;
215 * Get the unique backend name
217 * We may have multiple different backends of the same type.
218 * For example, we can have two Swift backends using different proxies.
222 final public function getName() {
227 * Get the domain identifier used for this backend (possibly empty).
232 final public function getDomainId() {
233 return $this->domainId
;
237 * Alias to getDomainId()
241 * @deprecated Since 1.34 Use getDomainId()
243 final public function getWikiId() {
244 return $this->getDomainId();
248 * Check if this backend is read-only
252 final public function isReadOnly() {
253 return ( $this->readOnly
!= '' );
257 * Get an explanatory message if this backend is read-only
259 * @return string|bool Returns false if the backend is not read-only
261 final public function getReadOnlyReason() {
262 return ( $this->readOnly
!= '' ) ?
$this->readOnly
: false;
266 * Get the a bitfield of extra features supported by the backend medium
268 * @return int Bitfield of FileBackend::ATTR_* flags
271 public function getFeatures() {
272 return self
::ATTR_UNICODE_PATHS
;
276 * Check if the backend medium supports a field of extra features
278 * @param int $bitfield Bitfield of FileBackend::ATTR_* flags
282 final public function hasFeatures( $bitfield ) {
283 return ( $this->getFeatures() & $bitfield ) === $bitfield;
287 * This is the main entry point into the backend for write operations.
288 * Callers supply an ordered list of operations to perform as a transaction.
289 * Files will be locked, the stat cache cleared, and then the operations attempted.
290 * If any serious errors occur, all attempted operations will be rolled back.
292 * $ops is an array of arrays. The outer array holds a list of operations.
293 * Each inner array is a set of key value pairs that specify an operation.
295 * Supported operations and their parameters. The supported actions are:
301 * - describe (since 1.21)
304 * FSFile/TempFSFile object support was added in 1.27.
306 * a) Create a new file in storage with the contents of a string
310 * 'dst' => <storage path>,
311 * 'content' => <string of new file contents>,
312 * 'overwrite' => <boolean>,
313 * 'overwriteSame' => <boolean>,
314 * 'headers' => <HTTP header name/value map> # since 1.21
318 * b) Copy a file system file into storage
322 * 'src' => <file system path, FSFile, or TempFSFile>,
323 * 'dst' => <storage path>,
324 * 'overwrite' => <boolean>,
325 * 'overwriteSame' => <boolean>,
326 * 'headers' => <HTTP header name/value map> # since 1.21
330 * c) Copy a file within storage
334 * 'src' => <storage path>,
335 * 'dst' => <storage path>,
336 * 'overwrite' => <boolean>,
337 * 'overwriteSame' => <boolean>,
338 * 'ignoreMissingSource' => <boolean>, # since 1.21
339 * 'headers' => <HTTP header name/value map> # since 1.21
343 * d) Move a file within storage
347 * 'src' => <storage path>,
348 * 'dst' => <storage path>,
349 * 'overwrite' => <boolean>,
350 * 'overwriteSame' => <boolean>,
351 * 'ignoreMissingSource' => <boolean>, # since 1.21
352 * 'headers' => <HTTP header name/value map> # since 1.21
356 * e) Delete a file within storage
360 * 'src' => <storage path>,
361 * 'ignoreMissingSource' => <boolean>
365 * f) Update metadata for a file within storage
368 * 'op' => 'describe',
369 * 'src' => <storage path>,
370 * 'headers' => <HTTP header name/value map>
374 * g) Do nothing (no-op)
381 * Boolean flags for operations (operation-specific):
382 * - ignoreMissingSource : The operation will simply succeed and do
383 * nothing if the source file does not exist.
384 * - overwrite : Any destination file will be overwritten.
385 * - overwriteSame : If a file already exists at the destination with the
386 * same contents, then do nothing to the destination file
387 * instead of giving an error. This does not compare headers.
388 * This option is ignored if 'overwrite' is already provided.
389 * - headers : If supplied, the result of merging these headers with any
390 * existing source file headers (replacing conflicting ones)
391 * will be set as the destination file headers. Headers are
392 * deleted if their value is set to the empty string. When a
393 * file has headers they are included in responses to GET and
394 * HEAD requests to the backing store for that file.
395 * Header values should be no larger than 255 bytes, except for
396 * Content-Disposition. The system might ignore or truncate any
397 * headers that are too long to store (exact limits will vary).
398 * Backends that don't support metadata ignore this. (since 1.21)
400 * $opts is an associative of boolean flags, including:
401 * - force : Operation precondition errors no longer trigger an abort.
402 * Any remaining operations are still attempted. Unexpected
403 * failures may still cause remaining operations to be aborted.
404 * - nonLocking : No locks are acquired for the operations.
405 * This can increase performance for non-critical writes.
406 * This has no effect unless the 'force' flag is set.
407 * - nonJournaled : Don't log this operation batch in the file journal.
408 * This limits the ability of recovery scripts.
409 * - parallelize : Try to do operations in parallel when possible.
410 * - bypassReadOnly : Allow writes in read-only mode. (since 1.20)
411 * - preserveCache : Don't clear the process cache before checking files.
412 * This should only be used if all entries in the process
413 * cache were added after the files were already locked. (since 1.20)
415 * @note Remarks on locking:
416 * File system paths given to operations should refer to files that are
417 * already locked or otherwise safe from modification from other processes.
418 * Normally these files will be new temp files, which should be adequate.
422 * This returns a Status, which contains all warnings and fatals that occurred
423 * during the operation. The 'failCount', 'successCount', and 'success' members
424 * will reflect each operation attempted.
426 * The StatusValue will be "OK" unless:
427 * - a) unexpected operation errors occurred (network partitions, disk full...)
428 * - b) predicted operation errors occurred and 'force' was not set
430 * @param array $ops List of operations to execute in order
431 * @codingStandardsIgnoreStart
432 * @phan-param array{ignoreMissingSource?:bool,overwrite?:bool,overwriteSame?:bool,headers?:bool} $ops
433 * @param array $opts Batch operation options
434 * @phan-param array{force?:bool,nonLocking?:bool,nonJournaled?:bool,parallelize?:bool,bypassReadOnly?:bool,preserveCache?:bool} $opts
435 * @codingStandardsIgnoreEnd
436 * @return StatusValue
438 final public function doOperations( array $ops, array $opts = [] ) {
439 if ( empty( $opts['bypassReadOnly'] ) && $this->isReadOnly() ) {
440 return $this->newStatus( 'backend-fail-readonly', $this->name
, $this->readOnly
);
443 return $this->newStatus(); // nothing to do
446 $ops = $this->resolveFSFileObjects( $ops );
447 if ( empty( $opts['force'] ) ) { // sanity
448 unset( $opts['nonLocking'] );
451 /** @noinspection PhpUnusedLocalVariableInspection */
452 $scope = ScopedCallback
::newScopedIgnoreUserAbort(); // try to ignore client aborts
454 return $this->doOperationsInternal( $ops, $opts );
458 * @see FileBackend::doOperations()
461 * @return StatusValue
463 abstract protected function doOperationsInternal( array $ops, array $opts );
466 * Same as doOperations() except it takes a single operation.
467 * If you are doing a batch of operations that should either
468 * all succeed or all fail, then use that function instead.
470 * @see FileBackend::doOperations()
472 * @param array $op Operation
473 * @param array $opts Operation options
474 * @return StatusValue
476 final public function doOperation( array $op, array $opts = [] ) {
477 return $this->doOperations( [ $op ], $opts );
481 * Performs a single create operation.
482 * This sets $params['op'] to 'create' and passes it to doOperation().
484 * @see FileBackend::doOperation()
486 * @param array $params Operation parameters
487 * @param array $opts Operation options
488 * @return StatusValue
490 final public function create( array $params, array $opts = [] ) {
491 return $this->doOperation( [ 'op' => 'create' ] +
$params, $opts );
495 * Performs a single store operation.
496 * This sets $params['op'] to 'store' and passes it to doOperation().
498 * @see FileBackend::doOperation()
500 * @param array $params Operation parameters
501 * @param array $opts Operation options
502 * @return StatusValue
504 final public function store( array $params, array $opts = [] ) {
505 return $this->doOperation( [ 'op' => 'store' ] +
$params, $opts );
509 * Performs a single copy operation.
510 * This sets $params['op'] to 'copy' and passes it to doOperation().
512 * @see FileBackend::doOperation()
514 * @param array $params Operation parameters
515 * @param array $opts Operation options
516 * @return StatusValue
518 final public function copy( array $params, array $opts = [] ) {
519 return $this->doOperation( [ 'op' => 'copy' ] +
$params, $opts );
523 * Performs a single move operation.
524 * This sets $params['op'] to 'move' and passes it to doOperation().
526 * @see FileBackend::doOperation()
528 * @param array $params Operation parameters
529 * @param array $opts Operation options
530 * @return StatusValue
532 final public function move( array $params, array $opts = [] ) {
533 return $this->doOperation( [ 'op' => 'move' ] +
$params, $opts );
537 * Performs a single delete operation.
538 * This sets $params['op'] to 'delete' and passes it to doOperation().
540 * @see FileBackend::doOperation()
542 * @param array $params Operation parameters
543 * @param array $opts Operation options
544 * @return StatusValue
546 final public function delete( array $params, array $opts = [] ) {
547 return $this->doOperation( [ 'op' => 'delete' ] +
$params, $opts );
551 * Performs a single describe operation.
552 * This sets $params['op'] to 'describe' and passes it to doOperation().
554 * @see FileBackend::doOperation()
556 * @param array $params Operation parameters
557 * @param array $opts Operation options
558 * @return StatusValue
561 final public function describe( array $params, array $opts = [] ) {
562 return $this->doOperation( [ 'op' => 'describe' ] +
$params, $opts );
566 * Perform a set of independent file operations on some files.
568 * This does no locking, nor journaling, and possibly no stat calls.
569 * Any destination files that already exist will be overwritten.
570 * This should *only* be used on non-original files, like cache files.
572 * Supported operations and their parameters:
578 * - describe (since 1.21)
581 * FSFile/TempFSFile object support was added in 1.27.
583 * a) Create a new file in storage with the contents of a string
587 * 'dst' => <storage path>,
588 * 'content' => <string of new file contents>,
589 * 'headers' => <HTTP header name/value map> # since 1.21
593 * b) Copy a file system file into storage
597 * 'src' => <file system path, FSFile, or TempFSFile>,
598 * 'dst' => <storage path>,
599 * 'headers' => <HTTP header name/value map> # since 1.21
603 * c) Copy a file within storage
607 * 'src' => <storage path>,
608 * 'dst' => <storage path>,
609 * 'ignoreMissingSource' => <boolean>, # since 1.21
610 * 'headers' => <HTTP header name/value map> # since 1.21
614 * d) Move a file within storage
618 * 'src' => <storage path>,
619 * 'dst' => <storage path>,
620 * 'ignoreMissingSource' => <boolean>, # since 1.21
621 * 'headers' => <HTTP header name/value map> # since 1.21
625 * e) Delete a file within storage
629 * 'src' => <storage path>,
630 * 'ignoreMissingSource' => <boolean>
634 * f) Update metadata for a file within storage
637 * 'op' => 'describe',
638 * 'src' => <storage path>,
639 * 'headers' => <HTTP header name/value map>
643 * g) Do nothing (no-op)
650 * @par Boolean flags for operations (operation-specific):
651 * - ignoreMissingSource : The operation will simply succeed and do
652 * nothing if the source file does not exist.
653 * - headers : If supplied with a header name/value map, the backend will
654 * reply with these headers when GETs/HEADs of the destination
655 * file are made. Header values should be smaller than 256 bytes.
656 * Content-Disposition headers can be longer, though the system
657 * might ignore or truncate ones that are too long to store.
658 * Existing headers will remain, but these will replace any
659 * conflicting previous headers, and headers will be removed
660 * if they are set to an empty string.
661 * Backends that don't support metadata ignore this. (since 1.21)
663 * $opts is an associative of boolean flags, including:
664 * - bypassReadOnly : Allow writes in read-only mode (since 1.20)
667 * This returns a Status, which contains all warnings and fatals that occurred
668 * during the operation. The 'failCount', 'successCount', and 'success' members
669 * will reflect each operation attempted for the given files. The StatusValue will be
670 * considered "OK" as long as no fatal errors occurred.
672 * @param array $ops Set of operations to execute
673 * @phan-param array{ignoreMissingSource?:bool,headers?:bool} $ops
674 * @param array $opts Batch operation options
675 * @phan-param array{bypassReadOnly?:bool} $opts
676 * @return StatusValue
679 final public function doQuickOperations( array $ops, array $opts = [] ) {
680 if ( empty( $opts['bypassReadOnly'] ) && $this->isReadOnly() ) {
681 return $this->newStatus( 'backend-fail-readonly', $this->name
, $this->readOnly
);
684 return $this->newStatus(); // nothing to do
687 $ops = $this->resolveFSFileObjects( $ops );
688 foreach ( $ops as &$op ) {
689 $op['overwrite'] = true; // avoids RTTs in key/value stores
692 /** @noinspection PhpUnusedLocalVariableInspection */
693 $scope = ScopedCallback
::newScopedIgnoreUserAbort(); // try to ignore client aborts
695 return $this->doQuickOperationsInternal( $ops );
699 * @see FileBackend::doQuickOperations()
701 * @return StatusValue
704 abstract protected function doQuickOperationsInternal( array $ops );
707 * Same as doQuickOperations() except it takes a single operation.
708 * If you are doing a batch of operations, then use that function instead.
710 * @see FileBackend::doQuickOperations()
712 * @param array $op Operation
713 * @return StatusValue
716 final public function doQuickOperation( array $op ) {
717 return $this->doQuickOperations( [ $op ] );
721 * Performs a single quick create operation.
722 * This sets $params['op'] to 'create' and passes it to doQuickOperation().
724 * @see FileBackend::doQuickOperation()
726 * @param array $params Operation parameters
727 * @return StatusValue
730 final public function quickCreate( array $params ) {
731 return $this->doQuickOperation( [ 'op' => 'create' ] +
$params );
735 * Performs a single quick store operation.
736 * This sets $params['op'] to 'store' and passes it to doQuickOperation().
738 * @see FileBackend::doQuickOperation()
740 * @param array $params Operation parameters
741 * @return StatusValue
744 final public function quickStore( array $params ) {
745 return $this->doQuickOperation( [ 'op' => 'store' ] +
$params );
749 * Performs a single quick copy operation.
750 * This sets $params['op'] to 'copy' and passes it to doQuickOperation().
752 * @see FileBackend::doQuickOperation()
754 * @param array $params Operation parameters
755 * @return StatusValue
758 final public function quickCopy( array $params ) {
759 return $this->doQuickOperation( [ 'op' => 'copy' ] +
$params );
763 * Performs a single quick move operation.
764 * This sets $params['op'] to 'move' and passes it to doQuickOperation().
766 * @see FileBackend::doQuickOperation()
768 * @param array $params Operation parameters
769 * @return StatusValue
772 final public function quickMove( array $params ) {
773 return $this->doQuickOperation( [ 'op' => 'move' ] +
$params );
777 * Performs a single quick delete operation.
778 * This sets $params['op'] to 'delete' and passes it to doQuickOperation().
780 * @see FileBackend::doQuickOperation()
782 * @param array $params Operation parameters
783 * @return StatusValue
786 final public function quickDelete( array $params ) {
787 return $this->doQuickOperation( [ 'op' => 'delete' ] +
$params );
791 * Performs a single quick describe operation.
792 * This sets $params['op'] to 'describe' and passes it to doQuickOperation().
794 * @see FileBackend::doQuickOperation()
796 * @param array $params Operation parameters
797 * @return StatusValue
800 final public function quickDescribe( array $params ) {
801 return $this->doQuickOperation( [ 'op' => 'describe' ] +
$params );
805 * Concatenate a list of storage files into a single file system file.
806 * The target path should refer to a file that is already locked or
807 * otherwise safe from modification from other processes. Normally,
808 * the file will be a new temp file, which should be adequate.
810 * @param array $params Operation parameters, include:
811 * - srcs : ordered source storage paths (e.g. chunk1, chunk2, ...)
812 * - dst : file system path to 0-byte temp file
813 * - parallelize : try to do operations in parallel when possible
814 * @return StatusValue
816 abstract public function concatenate( array $params );
819 * Prepare a storage directory for usage.
820 * This will create any required containers and parent directories.
821 * Backends using key/value stores only need to create the container.
823 * The 'noAccess' and 'noListing' parameters works the same as in secure(),
824 * except they are only applied *if* the directory/container had to be created.
825 * These flags should always be set for directories that have private files.
826 * However, setting them is not guaranteed to actually do anything.
827 * Additional server configuration may be needed to achieve the desired effect.
829 * @param array $params Parameters include:
830 * - dir : storage directory
831 * - noAccess : try to deny file access (since 1.20)
832 * - noListing : try to deny file listing (since 1.20)
833 * - bypassReadOnly : allow writes in read-only mode (since 1.20)
834 * @return StatusValue
836 final public function prepare( array $params ) {
837 if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) {
838 return $this->newStatus( 'backend-fail-readonly', $this->name
, $this->readOnly
);
840 /** @noinspection PhpUnusedLocalVariableInspection */
841 $scope = ScopedCallback
::newScopedIgnoreUserAbort(); // try to ignore client aborts
842 return $this->doPrepare( $params );
846 * @see FileBackend::prepare()
847 * @param array $params
848 * @return StatusValue
850 abstract protected function doPrepare( array $params );
853 * Take measures to block web access to a storage directory and
854 * the container it belongs to. FS backends might add .htaccess
855 * files whereas key/value store backends might revoke container
856 * access to the storage user representing end-users in web requests.
858 * This is not guaranteed to actually make files or listings publicly hidden.
859 * Additional server configuration may be needed to achieve the desired effect.
861 * @param array $params Parameters include:
862 * - dir : storage directory
863 * - noAccess : try to deny file access
864 * - noListing : try to deny file listing
865 * - bypassReadOnly : allow writes in read-only mode (since 1.20)
866 * @return StatusValue
868 final public function secure( array $params ) {
869 if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) {
870 return $this->newStatus( 'backend-fail-readonly', $this->name
, $this->readOnly
);
872 /** @noinspection PhpUnusedLocalVariableInspection */
873 $scope = ScopedCallback
::newScopedIgnoreUserAbort(); // try to ignore client aborts
874 return $this->doSecure( $params );
878 * @see FileBackend::secure()
879 * @param array $params
880 * @return StatusValue
882 abstract protected function doSecure( array $params );
885 * Remove measures to block web access to a storage directory and
886 * the container it belongs to. FS backends might remove .htaccess
887 * files whereas key/value store backends might grant container
888 * access to the storage user representing end-users in web requests.
889 * This essentially can undo the result of secure() calls.
891 * This is not guaranteed to actually make files or listings publicly viewable.
892 * Additional server configuration may be needed to achieve the desired effect.
894 * @param array $params Parameters include:
895 * - dir : storage directory
896 * - access : try to allow file access
897 * - listing : try to allow file listing
898 * - bypassReadOnly : allow writes in read-only mode (since 1.20)
899 * @return StatusValue
902 final public function publish( array $params ) {
903 if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) {
904 return $this->newStatus( 'backend-fail-readonly', $this->name
, $this->readOnly
);
906 /** @noinspection PhpUnusedLocalVariableInspection */
907 $scope = ScopedCallback
::newScopedIgnoreUserAbort(); // try to ignore client aborts
908 return $this->doPublish( $params );
912 * @see FileBackend::publish()
913 * @param array $params
914 * @return StatusValue
916 abstract protected function doPublish( array $params );
919 * Delete a storage directory if it is empty.
920 * Backends using key/value stores may do nothing unless the directory
921 * is that of an empty container, in which case it will be deleted.
923 * @param array $params Parameters include:
924 * - dir : storage directory
925 * - recursive : recursively delete empty subdirectories first (since 1.20)
926 * - bypassReadOnly : allow writes in read-only mode (since 1.20)
927 * @return StatusValue
929 final public function clean( array $params ) {
930 if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) {
931 return $this->newStatus( 'backend-fail-readonly', $this->name
, $this->readOnly
);
933 /** @noinspection PhpUnusedLocalVariableInspection */
934 $scope = ScopedCallback
::newScopedIgnoreUserAbort(); // try to ignore client aborts
935 return $this->doClean( $params );
939 * @see FileBackend::clean()
940 * @param array $params
941 * @return StatusValue
943 abstract protected function doClean( array $params );
946 * Check if a file exists at a storage path in the backend.
947 * This returns false if only a directory exists at the path.
949 * @param array $params Parameters include:
950 * - src : source storage path
951 * - latest : use the latest available data
952 * @return bool|null Returns null on failure
954 abstract public function fileExists( array $params );
957 * Get the last-modified timestamp of the file at a storage path.
959 * @param array $params Parameters include:
960 * - src : source storage path
961 * - latest : use the latest available data
962 * @return string|bool TS_MW timestamp or false on failure
964 abstract public function getFileTimestamp( array $params );
967 * Get the contents of a file at a storage path in the backend.
968 * This should be avoided for potentially large files.
970 * @param array $params Parameters include:
971 * - src : source storage path
972 * - latest : use the latest available data
973 * @return string|bool Returns false on failure
975 final public function getFileContents( array $params ) {
976 $contents = $this->getFileContentsMulti(
977 [ 'srcs' => [ $params['src'] ] ] +
$params );
979 return $contents[$params['src']];
983 * Like getFileContents() except it takes an array of storage paths
984 * and returns a map of storage paths to strings (or null on failure).
985 * The map keys (paths) are in the same order as the provided list of paths.
987 * @see FileBackend::getFileContents()
989 * @param array $params Parameters include:
990 * - srcs : list of source storage paths
991 * - latest : use the latest available data
992 * - parallelize : try to do operations in parallel when possible
993 * @return array Map of (path name => string or false on failure)
996 abstract public function getFileContentsMulti( array $params );
999 * Get metadata about a file at a storage path in the backend.
1000 * If the file does not exist, then this returns false.
1001 * Otherwise, the result is an associative array that includes:
1002 * - headers : map of HTTP headers used for GET/HEAD requests (name => value)
1003 * - metadata : map of file metadata (name => value)
1004 * Metadata keys and headers names will be returned in all lower-case.
1005 * Additional values may be included for internal use only.
1007 * Use FileBackend::hasFeatures() to check how well this is supported.
1009 * @param array $params
1011 * - src : source storage path
1012 * - latest : use the latest available data
1013 * @return array|bool Returns false on failure
1016 abstract public function getFileXAttributes( array $params );
1019 * Get the size (bytes) of a file at a storage path in the backend.
1021 * @param array $params Parameters include:
1022 * - src : source storage path
1023 * - latest : use the latest available data
1024 * @return int|bool Returns false on failure
1026 abstract public function getFileSize( array $params );
1029 * Get quick information about a file at a storage path in the backend.
1030 * If the file does not exist, then this returns false.
1031 * Otherwise, the result is an associative array that includes:
1032 * - mtime : the last-modified timestamp (TS_MW)
1033 * - size : the file size (bytes)
1034 * Additional values may be included for internal use only.
1036 * @param array $params Parameters include:
1037 * - src : source storage path
1038 * - latest : use the latest available data
1039 * @return array|bool|null Returns null on failure
1041 abstract public function getFileStat( array $params );
1044 * Get a SHA-1 hash of the file at a storage path in the backend.
1046 * @param array $params Parameters include:
1047 * - src : source storage path
1048 * - latest : use the latest available data
1049 * @return string|bool Hash string or false on failure
1051 abstract public function getFileSha1Base36( array $params );
1054 * Get the properties of the file at a storage path in the backend.
1055 * This gives the result of FSFile::getProps() on a local copy of the file.
1057 * @param array $params Parameters include:
1058 * - src : source storage path
1059 * - latest : use the latest available data
1060 * @return array Returns FSFile::placeholderProps() on failure
1062 abstract public function getFileProps( array $params );
1065 * Stream the file at a storage path in the backend.
1067 * If the file does not exists, an HTTP 404 error will be given.
1068 * Appropriate HTTP headers (Status, Content-Type, Content-Length)
1069 * will be sent if streaming began, while none will be sent otherwise.
1070 * Implementations should flush the output buffer before sending data.
1072 * @param array $params Parameters include:
1073 * - src : source storage path
1074 * - headers : list of additional HTTP headers to send if the file exists
1075 * - options : HTTP request header map with lower case keys (since 1.28). Supports:
1076 * range : format is "bytes=(\d*-\d*)"
1077 * if-modified-since : format is an HTTP date
1078 * - headless : only include the body (and headers from "headers") (since 1.28)
1079 * - latest : use the latest available data
1080 * - allowOB : preserve any output buffers (since 1.28)
1081 * @return StatusValue
1083 abstract public function streamFile( array $params );
1086 * Returns a file system file, identical to the file at a storage path.
1087 * The file returned is either:
1088 * - a) A local copy of the file at a storage path in the backend.
1089 * The temporary copy will have the same extension as the source.
1090 * - b) An original of the file at a storage path in the backend.
1091 * Temporary files may be purged when the file object falls out of scope.
1093 * Write operations should *never* be done on this file as some backends
1094 * may do internal tracking or may be instances of FileBackendMultiWrite.
1095 * In that latter case, there are copies of the file that must stay in sync.
1096 * Additionally, further calls to this function may return the same file.
1098 * @param array $params Parameters include:
1099 * - src : source storage path
1100 * - latest : use the latest available data
1101 * @return FSFile|null Returns null on failure
1103 final public function getLocalReference( array $params ) {
1104 $fsFiles = $this->getLocalReferenceMulti(
1105 [ 'srcs' => [ $params['src'] ] ] +
$params );
1107 return $fsFiles[$params['src']];
1111 * Like getLocalReference() except it takes an array of storage paths
1112 * and returns a map of storage paths to FSFile objects (or null on failure).
1113 * The map keys (paths) are in the same order as the provided list of paths.
1115 * @see FileBackend::getLocalReference()
1117 * @param array $params Parameters include:
1118 * - srcs : list of source storage paths
1119 * - latest : use the latest available data
1120 * - parallelize : try to do operations in parallel when possible
1121 * @return array Map of (path name => FSFile or null on failure)
1124 abstract public function getLocalReferenceMulti( array $params );
1127 * Get a local copy on disk of the file at a storage path in the backend.
1128 * The temporary copy will have the same file extension as the source.
1129 * Temporary files may be purged when the file object falls out of scope.
1131 * @param array $params Parameters include:
1132 * - src : source storage path
1133 * - latest : use the latest available data
1134 * @return TempFSFile|null Returns null on failure
1136 final public function getLocalCopy( array $params ) {
1137 $tmpFiles = $this->getLocalCopyMulti(
1138 [ 'srcs' => [ $params['src'] ] ] +
$params );
1140 return $tmpFiles[$params['src']];
1144 * Like getLocalCopy() except it takes an array of storage paths and
1145 * returns a map of storage paths to TempFSFile objects (or null on failure).
1146 * The map keys (paths) are in the same order as the provided list of paths.
1148 * @see FileBackend::getLocalCopy()
1150 * @param array $params Parameters include:
1151 * - srcs : list of source storage paths
1152 * - latest : use the latest available data
1153 * - parallelize : try to do operations in parallel when possible
1154 * @return array Map of (path name => TempFSFile or null on failure)
1157 abstract public function getLocalCopyMulti( array $params );
1160 * Return an HTTP URL to a given file that requires no authentication to use.
1161 * The URL may be pre-authenticated (via some token in the URL) and temporary.
1162 * This will return null if the backend cannot make an HTTP URL for the file.
1164 * This is useful for key/value stores when using scripts that seek around
1165 * large files and those scripts (and the backend) support HTTP Range headers.
1166 * Otherwise, one would need to use getLocalReference(), which involves loading
1167 * the entire file on to local disk.
1169 * @param array $params Parameters include:
1170 * - src : source storage path
1171 * - ttl : lifetime (seconds) if pre-authenticated; default is 1 day
1172 * @return string|null
1175 abstract public function getFileHttpUrl( array $params );
1178 * Check if a directory exists at a given storage path
1180 * For backends using key/value stores, a directory is said to exist whenever
1181 * there exist any files with paths using the given directory path as a prefix
1182 * followed by a forward slash. For example, if there is a file called
1183 * "mwstore://backend/container/dir/path.svg" then directories are said to exist
1184 * at "mwstore://backend/container" and "mwstore://backend/container/dir". These
1185 * can be thought of as "virtual" directories.
1187 * Backends that directly use a filesystem layer might enumerate empty directories.
1188 * The clean() method should always be used when files are deleted or moved if this
1189 * is a concern. This is a trade-off to avoid write amplication/contention on file
1190 * changes or read amplification when calling this method.
1192 * Storage backends with eventual consistency might return stale data.
1194 * @see FileBackend::clean()
1196 * @param array $params Parameters include:
1197 * - dir : storage directory
1198 * @return bool|null Whether a directory exists or null on failure
1201 abstract public function directoryExists( array $params );
1204 * Get an iterator to list *all* directories under a storage directory
1206 * If the directory is of the form "mwstore://backend/container",
1207 * then all directories in the container will be listed.
1208 * If the directory is of form "mwstore://backend/container/dir",
1209 * then all directories directly under that directory will be listed.
1210 * Results will be storage directories relative to the given directory.
1212 * Storage backends with eventual consistency might return stale data.
1214 * Failures during iteration can result in FileBackendError exceptions (since 1.22).
1216 * @see FileBackend::directoryExists()
1218 * @param array $params Parameters include:
1219 * - dir : storage directory
1220 * - topOnly : only return direct child dirs of the directory
1221 * @return Traversable|array|null Directory list enumerator null on failure
1224 abstract public function getDirectoryList( array $params );
1227 * Same as FileBackend::getDirectoryList() except only lists
1228 * directories that are immediately under the given directory.
1230 * Storage backends with eventual consistency might return stale data.
1232 * Failures during iteration can result in FileBackendError exceptions (since 1.22).
1234 * @see FileBackend::directoryExists()
1236 * @param array $params Parameters include:
1237 * - dir : storage directory
1238 * @return Traversable|array|null Directory list enumerator or null on failure
1241 final public function getTopDirectoryList( array $params ) {
1242 return $this->getDirectoryList( [ 'topOnly' => true ] +
$params );
1246 * Get an iterator to list *all* stored files under a storage directory
1248 * If the directory is of the form "mwstore://backend/container", then all
1249 * files in the container will be listed. If the directory is of form
1250 * "mwstore://backend/container/dir", then all files under that directory will
1251 * be listed. Results will be storage paths relative to the given directory.
1253 * Storage backends with eventual consistency might return stale data.
1255 * Failures during iteration can result in FileBackendError exceptions (since 1.22).
1257 * @param array $params Parameters include:
1258 * - dir : storage directory
1259 * - topOnly : only return direct child files of the directory (since 1.20)
1260 * - adviseStat : set to true if stat requests will be made on the files (since 1.22)
1261 * @return Traversable|array|null File list enumerator or null on failure
1263 abstract public function getFileList( array $params );
1266 * Same as FileBackend::getFileList() except only lists
1267 * files that are immediately under the given directory.
1269 * Storage backends with eventual consistency might return stale data.
1271 * Failures during iteration can result in FileBackendError exceptions (since 1.22).
1273 * @param array $params Parameters include:
1274 * - dir : storage directory
1275 * - adviseStat : set to true if stat requests will be made on the files (since 1.22)
1276 * @return Traversable|array|null File list enumerator or null on failure
1279 final public function getTopFileList( array $params ) {
1280 return $this->getFileList( [ 'topOnly' => true ] +
$params );
1284 * Preload persistent file stat cache and property cache into in-process cache.
1285 * This should be used when stat calls will be made on a known list of a many files.
1287 * @see FileBackend::getFileStat()
1289 * @param array $paths Storage paths
1291 abstract public function preloadCache( array $paths );
1294 * Invalidate any in-process file stat and property cache.
1295 * If $paths is given, then only the cache for those files will be cleared.
1297 * @see FileBackend::getFileStat()
1299 * @param array|null $paths Storage paths (optional)
1301 abstract public function clearCache( array $paths = null );
1304 * Preload file stat information (concurrently if possible) into in-process cache.
1306 * This should be used when stat calls will be made on a known list of a many files.
1307 * This does not make use of the persistent file stat cache.
1309 * @see FileBackend::getFileStat()
1311 * @param array $params Parameters include:
1312 * - srcs : list of source storage paths
1313 * - latest : use the latest available data
1314 * @return bool Whether all requests proceeded without I/O errors (since 1.24)
1317 abstract public function preloadFileStat( array $params );
1320 * Lock the files at the given storage paths in the backend.
1321 * This will either lock all the files or none (on failure).
1323 * Callers should consider using getScopedFileLocks() instead.
1325 * @param array $paths Storage paths
1326 * @param int $type LockManager::LOCK_* constant
1327 * @param int $timeout Timeout in seconds (0 means non-blocking) (since 1.24)
1328 * @return StatusValue
1330 final public function lockFiles( array $paths, $type, $timeout = 0 ) {
1331 $paths = array_map( 'FileBackend::normalizeStoragePath', $paths );
1333 return $this->wrapStatus( $this->lockManager
->lock( $paths, $type, $timeout ) );
1337 * Unlock the files at the given storage paths in the backend.
1339 * @param array $paths Storage paths
1340 * @param int $type LockManager::LOCK_* constant
1341 * @return StatusValue
1343 final public function unlockFiles( array $paths, $type ) {
1344 $paths = array_map( 'FileBackend::normalizeStoragePath', $paths );
1346 return $this->wrapStatus( $this->lockManager
->unlock( $paths, $type ) );
1350 * Lock the files at the given storage paths in the backend.
1351 * This will either lock all the files or none (on failure).
1352 * On failure, the StatusValue object will be updated with errors.
1354 * Once the return value goes out scope, the locks will be released and
1355 * the StatusValue updated. Unlock fatals will not change the StatusValue "OK" value.
1357 * @see ScopedLock::factory()
1359 * @param array $paths List of storage paths or map of lock types to path lists
1360 * @param int|string $type LockManager::LOCK_* constant or "mixed"
1361 * @param StatusValue $status StatusValue to update on lock/unlock
1362 * @param int $timeout Timeout in seconds (0 means non-blocking) (since 1.24)
1363 * @return ScopedLock|null Returns null on failure
1365 final public function getScopedFileLocks(
1366 array $paths, $type, StatusValue
$status, $timeout = 0
1368 if ( $type === 'mixed' ) {
1369 foreach ( $paths as &$typePaths ) {
1370 $typePaths = array_map( 'FileBackend::normalizeStoragePath', $typePaths );
1373 $paths = array_map( 'FileBackend::normalizeStoragePath', $paths );
1376 return ScopedLock
::factory( $this->lockManager
, $paths, $type, $status, $timeout );
1380 * Get an array of scoped locks needed for a batch of file operations.
1382 * Normally, FileBackend::doOperations() handles locking, unless
1383 * the 'nonLocking' param is passed in. This function is useful if you
1384 * want the files to be locked for a broader scope than just when the
1385 * files are changing. For example, if you need to update DB metadata,
1386 * you may want to keep the files locked until finished.
1388 * @see FileBackend::doOperations()
1390 * @param array $ops List of file operations to FileBackend::doOperations()
1391 * @param StatusValue $status StatusValue to update on lock/unlock
1392 * @return ScopedLock|null
1395 abstract public function getScopedLocksForOps( array $ops, StatusValue
$status );
1398 * Get the root storage path of this backend.
1399 * All container paths are "subdirectories" of this path.
1401 * @return string Storage path
1404 final public function getRootStoragePath() {
1405 return "mwstore://{$this->name}";
1409 * Get the storage path for the given container for this backend
1411 * @param string $container Container name
1412 * @return string Storage path
1415 final public function getContainerStoragePath( $container ) {
1416 return $this->getRootStoragePath() . "/{$container}";
1420 * Get the file journal object for this backend
1422 * @return FileJournal
1424 final public function getJournal() {
1425 return $this->fileJournal
;
1429 * Convert FSFile 'src' paths to string paths (with an 'srcRef' field set to the FSFile)
1431 * The 'srcRef' field keeps any TempFSFile objects in scope for the backend to have it
1432 * around as long it needs (which may vary greatly depending on configuration)
1434 * @param array $ops File operation batch for FileBaclend::doOperations()
1435 * @return array File operation batch
1437 protected function resolveFSFileObjects( array $ops ) {
1438 foreach ( $ops as &$op ) {
1439 $src = $op['src'] ??
null;
1440 if ( $src instanceof FSFile
) {
1441 $op['srcRef'] = $src;
1442 $op['src'] = $src->getPath();
1451 * Check if a given path is a "mwstore://" path.
1452 * This does not do any further validation or any existence checks.
1454 * @param string $path
1457 final public static function isStoragePath( $path ) {
1458 return ( strpos( $path, 'mwstore://' ) === 0 );
1462 * Split a storage path into a backend name, a container name,
1463 * and a relative file path. The relative path may be the empty string.
1464 * This does not do any path normalization or traversal checks.
1466 * @param string $storagePath
1467 * @return array (backend, container, rel object) or (null, null, null)
1469 final public static function splitStoragePath( $storagePath ) {
1470 if ( self
::isStoragePath( $storagePath ) ) {
1471 // Remove the "mwstore://" prefix and split the path
1472 $parts = explode( '/', substr( $storagePath, 10 ), 3 );
1473 if ( count( $parts ) >= 2 && $parts[0] != '' && $parts[1] != '' ) {
1474 if ( count( $parts ) == 3 ) {
1475 return $parts; // e.g. "backend/container/path"
1477 return [ $parts[0], $parts[1], '' ]; // e.g. "backend/container"
1482 return [ null, null, null ];
1486 * Normalize a storage path by cleaning up directory separators.
1487 * Returns null if the path is not of the format of a valid storage path.
1489 * @param string $storagePath
1490 * @return string|null
1492 final public static function normalizeStoragePath( $storagePath ) {
1493 list( $backend, $container, $relPath ) = self
::splitStoragePath( $storagePath );
1494 if ( $relPath !== null ) { // must be for this backend
1495 $relPath = self
::normalizeContainerPath( $relPath );
1496 if ( $relPath !== null ) {
1497 return ( $relPath != '' )
1498 ?
"mwstore://{$backend}/{$container}/{$relPath}"
1499 : "mwstore://{$backend}/{$container}";
1507 * Get the parent storage directory of a storage path.
1508 * This returns a path like "mwstore://backend/container",
1509 * "mwstore://backend/container/...", or null if there is no parent.
1511 * @param string $storagePath
1512 * @return string|null
1514 final public static function parentStoragePath( $storagePath ) {
1515 $storagePath = dirname( $storagePath );
1516 list( , , $rel ) = self
::splitStoragePath( $storagePath );
1518 return ( $rel === null ) ?
null : $storagePath;
1522 * Get the final extension from a storage or FS path
1524 * @param string $path
1525 * @param string $case One of (rawcase, uppercase, lowercase) (since 1.24)
1528 final public static function extensionFromPath( $path, $case = 'lowercase' ) {
1529 $i = strrpos( $path, '.' );
1530 $ext = $i ?
substr( $path, $i +
1 ) : '';
1532 if ( $case === 'lowercase' ) {
1533 $ext = strtolower( $ext );
1534 } elseif ( $case === 'uppercase' ) {
1535 $ext = strtoupper( $ext );
1542 * Check if a relative path has no directory traversals
1544 * @param string $path
1548 final public static function isPathTraversalFree( $path ) {
1549 return ( self
::normalizeContainerPath( $path ) !== null );
1553 * Build a Content-Disposition header value per RFC 6266.
1555 * @param string $type One of (attachment, inline)
1556 * @param string $filename Suggested file name (should not contain slashes)
1557 * @throws InvalidArgumentException
1561 final public static function makeContentDisposition( $type, $filename = '' ) {
1564 $type = strtolower( $type );
1565 if ( !in_array( $type, [ 'inline', 'attachment' ] ) ) {
1566 throw new InvalidArgumentException( "Invalid Content-Disposition type '$type'." );
1570 if ( strlen( $filename ) ) {
1571 $parts[] = "filename*=UTF-8''" . rawurlencode( basename( $filename ) );
1574 return implode( ';', $parts );
1578 * Validate and normalize a relative storage path.
1579 * Null is returned if the path involves directory traversal.
1580 * Traversal is insecure for FS backends and broken for others.
1582 * This uses the same traversal protection as Title::secureAndSplit().
1584 * @param string $path Storage path relative to a container
1585 * @return string|null
1587 final protected static function normalizeContainerPath( $path ) {
1588 // Normalize directory separators
1589 $path = strtr( $path, '\\', '/' );
1590 // Collapse any consecutive directory separators
1591 $path = preg_replace( '![/]{2,}!', '/', $path );
1592 // Remove any leading directory separator
1593 $path = ltrim( $path, '/' );
1594 // Use the same traversal protection as Title::secureAndSplit()
1595 if ( strpos( $path, '.' ) !== false ) {
1599 strpos( $path, './' ) === 0 ||
1600 strpos( $path, '../' ) === 0 ||
1601 strpos( $path, '/./' ) !== false ||
1602 strpos( $path, '/../' ) !== false
1612 * Yields the result of the status wrapper callback on either:
1613 * - StatusValue::newGood() if this method is called without parameters
1614 * - StatusValue::newFatal() with all parameters to this method if passed in
1616 * @param string ...$args
1617 * @return StatusValue
1619 final protected function newStatus( ...$args ) {
1620 if ( count( $args ) ) {
1621 $sv = StatusValue
::newFatal( ...$args );
1623 $sv = StatusValue
::newGood();
1626 return $this->wrapStatus( $sv );
1630 * @param StatusValue $sv
1631 * @return StatusValue Modified status or StatusValue subclass
1633 final protected function wrapStatus( StatusValue
$sv ) {
1634 return $this->statusWrapper ?
call_user_func( $this->statusWrapper
, $sv ) : $sv;
1638 * @param string $section
1639 * @return ScopedCallback|null
1641 protected function scopedProfileSection( $section ) {
1642 return $this->profiler ?
( $this->profiler
)( $section ) : null;
1645 protected function resetOutputBuffer() {
1646 while ( ob_get_status() ) {
1647 if ( !ob_end_clean() ) {
1648 // Could not remove output buffer handler; abort now
1649 // to avoid getting in some kind of infinite loop.