follow-up r98710/r104410. I personally think that forRefresh is confusing, since...
[lhc/web/wiklou.git] / includes / filerepo / file / File.php
1 <?php
2 /**
3 * Base code for files.
4 *
5 * @file
6 * @ingroup FileRepo
7 */
8
9 /**
10 * Implements some public methods and some protected utility functions which
11 * are required by multiple child classes. Contains stub functionality for
12 * unimplemented public methods.
13 *
14 * Stub functions which should be overridden are marked with STUB. Some more
15 * concrete functions are also typically overridden by child classes.
16 *
17 * Note that only the repo object knows what its file class is called. You should
18 * never name a file class explictly outside of the repo class. Instead use the
19 * repo's factory functions to generate file objects, for example:
20 *
21 * RepoGroup::singleton()->getLocalRepo()->newFile($title);
22 *
23 * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
24 * in most cases.
25 *
26 * @ingroup FileRepo
27 */
28 abstract class File {
29 const DELETED_FILE = 1;
30 const DELETED_COMMENT = 2;
31 const DELETED_USER = 4;
32 const DELETED_RESTRICTED = 8;
33
34 /** Force rendering in the current process */
35 const RENDER_NOW = 1;
36 /**
37 * Force rendering even if thumbnail already exist and using RENDER_NOW
38 * I.e. you have to pass both flags: File::RENDER_NOW | File::RENDER_FORCE
39 */
40 const RENDER_FORCE = 2;
41
42 const DELETE_SOURCE = 1;
43
44 /**
45 * Some member variables can be lazy-initialised using __get(). The
46 * initialisation function for these variables is always a function named
47 * like getVar(), where Var is the variable name with upper-case first
48 * letter.
49 *
50 * The following variables are initialised in this way in this base class:
51 * name, extension, handler, path, canRender, isSafeFile,
52 * transformScript, hashPath, pageCount, url
53 *
54 * Code within this class should generally use the accessor function
55 * directly, since __get() isn't re-entrant and therefore causes bugs that
56 * depend on initialisation order.
57 */
58
59 /**
60 * The following member variables are not lazy-initialised
61 */
62
63 /**
64 * @var FileRepo|false
65 */
66 var $repo;
67
68 /**
69 * @var Title|false
70 */
71 var $title;
72
73 var $lastError, $redirected, $redirectedTitle;
74
75 /**
76 * @var FSFile|false
77 */
78 protected $fsFile;
79
80 /**
81 * @var MediaHandler
82 */
83 protected $handler;
84
85 /**
86 * @var string
87 */
88 protected $url, $extension, $name, $path, $hashPath, $pageCount, $transformScript;
89
90 /**
91 * @var bool
92 */
93 protected $canRender, $isSafeFile;
94
95 /**
96 * @var string Required Repository class type
97 */
98 protected $repoClass = 'FileRepo';
99
100 /**
101 * Call this constructor from child classes.
102 *
103 * Both $title and $repo are optional, though some functions
104 * may return false or throw exceptions if they are not set.
105 * Most subclasses will want to call assertRepoDefined() here.
106 *
107 * @param $title Title|string|false
108 * @param $repo FileRepo|false
109 */
110 function __construct( $title, $repo ) {
111 if ( $title !== false ) { // subclasses may not use MW titles
112 $title = self::normalizeTitle( $title, 'exception' );
113 }
114 $this->title = $title;
115 $this->repo = $repo;
116 }
117
118 /**
119 * Given a string or Title object return either a
120 * valid Title object with namespace NS_FILE or null
121 *
122 * @param $title Title|string
123 * @param $exception string|false Use 'exception' to throw an error on bad titles
124 * @return Title|null
125 */
126 static function normalizeTitle( $title, $exception = false ) {
127 $ret = $title;
128 if ( $ret instanceof Title ) {
129 # Normalize NS_MEDIA -> NS_FILE
130 if ( $ret->getNamespace() == NS_MEDIA ) {
131 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
132 # Sanity check the title namespace
133 } elseif ( $ret->getNamespace() !== NS_FILE ) {
134 $ret = null;
135 }
136 } else {
137 # Convert strings to Title objects
138 $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
139 }
140 if ( !$ret && $exception !== false ) {
141 throw new MWException( "`$title` is not a valid file title." );
142 }
143 return $ret;
144 }
145
146 function __get( $name ) {
147 $function = array( $this, 'get' . ucfirst( $name ) );
148 if ( !is_callable( $function ) ) {
149 return null;
150 } else {
151 $this->$name = call_user_func( $function );
152 return $this->$name;
153 }
154 }
155
156 /**
157 * Normalize a file extension to the common form, and ensure it's clean.
158 * Extensions with non-alphanumeric characters will be discarded.
159 *
160 * @param $ext string (without the .)
161 * @return string
162 */
163 static function normalizeExtension( $ext ) {
164 $lower = strtolower( $ext );
165 $squish = array(
166 'htm' => 'html',
167 'jpeg' => 'jpg',
168 'mpeg' => 'mpg',
169 'tiff' => 'tif',
170 'ogv' => 'ogg' );
171 if( isset( $squish[$lower] ) ) {
172 return $squish[$lower];
173 } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
174 return $lower;
175 } else {
176 return '';
177 }
178 }
179
180 /**
181 * Checks if file extensions are compatible
182 *
183 * @param $old File Old file
184 * @param $new string New name
185 *
186 * @return bool|null
187 */
188 static function checkExtensionCompatibility( File $old, $new ) {
189 $oldMime = $old->getMimeType();
190 $n = strrpos( $new, '.' );
191 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
192 $mimeMagic = MimeMagic::singleton();
193 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
194 }
195
196 /**
197 * Upgrade the database row if there is one
198 * Called by ImagePage
199 * STUB
200 */
201 function upgradeRow() {}
202
203 /**
204 * Split an internet media type into its two components; if not
205 * a two-part name, set the minor type to 'unknown'.
206 *
207 * @param string $mime "text/html" etc
208 * @return array ("text", "html") etc
209 */
210 public static function splitMime( $mime ) {
211 if( strpos( $mime, '/' ) !== false ) {
212 return explode( '/', $mime, 2 );
213 } else {
214 return array( $mime, 'unknown' );
215 }
216 }
217
218 /**
219 * Return the name of this file
220 *
221 * @return string
222 */
223 public function getName() {
224 if ( !isset( $this->name ) ) {
225 $this->assertRepoDefined();
226 $this->name = $this->repo->getNameFromTitle( $this->title );
227 }
228 return $this->name;
229 }
230
231 /**
232 * Get the file extension, e.g. "svg"
233 *
234 * @return string
235 */
236 function getExtension() {
237 if ( !isset( $this->extension ) ) {
238 $n = strrpos( $this->getName(), '.' );
239 $this->extension = self::normalizeExtension(
240 $n ? substr( $this->getName(), $n + 1 ) : '' );
241 }
242 return $this->extension;
243 }
244
245 /**
246 * Return the associated title object
247 *
248 * @return Title|false
249 */
250 public function getTitle() {
251 return $this->title;
252 }
253
254 /**
255 * Return the title used to find this file
256 *
257 * @return Title
258 */
259 public function getOriginalTitle() {
260 if ( $this->redirected ) {
261 return $this->getRedirectedTitle();
262 }
263 return $this->title;
264 }
265
266 /**
267 * Return the URL of the file
268 *
269 * @return string
270 */
271 public function getUrl() {
272 if ( !isset( $this->url ) ) {
273 $this->assertRepoDefined();
274 $this->url = $this->repo->getZoneUrl( 'public' ) . '/' . $this->getUrlRel();
275 }
276 return $this->url;
277 }
278
279 /**
280 * Return a fully-qualified URL to the file.
281 * Upload URL paths _may or may not_ be fully qualified, so
282 * we check. Local paths are assumed to belong on $wgServer.
283 *
284 * @return String
285 */
286 public function getFullUrl() {
287 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
288 }
289
290 /**
291 * @return string
292 */
293 public function getCanonicalUrl() {
294 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
295 }
296
297 /**
298 * @return string
299 */
300 function getViewURL() {
301 if( $this->mustRender()) {
302 if( $this->canRender() ) {
303 return $this->createThumb( $this->getWidth() );
304 } else {
305 wfDebug(__METHOD__.': supposed to render '.$this->getName().' ('.$this->getMimeType()."), but can't!\n");
306 return $this->getURL(); #hm... return NULL?
307 }
308 } else {
309 return $this->getURL();
310 }
311 }
312
313 /**
314 * Return the storage path to the file. Note that this does
315 * not mean that a file actually exists under that location.
316 *
317 * This path depends on whether directory hashing is active or not,
318 * i.e. whether the files are all found in the same directory,
319 * or in hashed paths like /images/3/3c.
320 *
321 * Most callers don't check the return value, but ForeignAPIFile::getPath
322 * returns false.
323 *
324 * @return string|false
325 */
326 public function getPath() {
327 if ( !isset( $this->path ) ) {
328 $this->assertRepoDefined();
329 $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
330 }
331 return $this->path;
332 }
333
334 /**
335 * Get an FS copy or original of this file and return the path.
336 * Returns false on failure. Callers must not alter the file.
337 * Temporary files are cleared automatically.
338 *
339 * @return string|false
340 */
341 public function getLocalRefPath() {
342 $this->assertRepoDefined();
343 if ( !isset( $this->fsFile ) ) {
344 $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
345 if ( !$this->fsFile ) {
346 $this->fsFile = false; // null => false; cache negative hits
347 }
348 }
349 return ( $this->fsFile )
350 ? $this->fsFile->getPath()
351 : false;
352 }
353
354 /**
355 * Return the width of the image. Returns false if the width is unknown
356 * or undefined.
357 *
358 * STUB
359 * Overridden by LocalFile, UnregisteredLocalFile
360 *
361 * @param $page int
362 *
363 * @return number
364 */
365 public function getWidth( $page = 1 ) {
366 return false;
367 }
368
369 /**
370 * Return the height of the image. Returns false if the height is unknown
371 * or undefined
372 *
373 * STUB
374 * Overridden by LocalFile, UnregisteredLocalFile
375 *
376 * @param $page int
377 *
378 * @return false|number
379 */
380 public function getHeight( $page = 1 ) {
381 return false;
382 }
383
384 /**
385 * Returns ID or name of user who uploaded the file
386 * STUB
387 *
388 * @param $type string 'text' or 'id'
389 *
390 * @return string|int
391 */
392 public function getUser( $type = 'text' ) {
393 return null;
394 }
395
396 /**
397 * Get the duration of a media file in seconds
398 *
399 * @return number
400 */
401 public function getLength() {
402 $handler = $this->getHandler();
403 if ( $handler ) {
404 return $handler->getLength( $this );
405 } else {
406 return 0;
407 }
408 }
409
410 /**
411 * Return true if the file is vectorized
412 *
413 * @return bool
414 */
415 public function isVectorized() {
416 $handler = $this->getHandler();
417 if ( $handler ) {
418 return $handler->isVectorized( $this );
419 } else {
420 return false;
421 }
422 }
423
424 /**
425 * Get handler-specific metadata
426 * Overridden by LocalFile, UnregisteredLocalFile
427 * STUB
428 */
429 public function getMetadata() {
430 return false;
431 }
432
433 /**
434 * get versioned metadata
435 *
436 * @param $metadata Mixed Array or String of (serialized) metadata
437 * @param $version integer version number.
438 * @return Array containing metadata, or what was passed to it on fail (unserializing if not array)
439 */
440 public function convertMetadataVersion($metadata, $version) {
441 $handler = $this->getHandler();
442 if ( !is_array( $metadata ) ) {
443 // Just to make the return type consistent
444 $metadata = unserialize( $metadata );
445 }
446 if ( $handler ) {
447 return $handler->convertMetadataVersion( $metadata, $version );
448 } else {
449 return $metadata;
450 }
451 }
452
453 /**
454 * Return the bit depth of the file
455 * Overridden by LocalFile
456 * STUB
457 */
458 public function getBitDepth() {
459 return 0;
460 }
461
462 /**
463 * Return the size of the image file, in bytes
464 * Overridden by LocalFile, UnregisteredLocalFile
465 * STUB
466 */
467 public function getSize() {
468 return false;
469 }
470
471 /**
472 * Returns the mime type of the file.
473 * Overridden by LocalFile, UnregisteredLocalFile
474 * STUB
475 *
476 * @return string
477 */
478 function getMimeType() {
479 return 'unknown/unknown';
480 }
481
482 /**
483 * Return the type of the media in the file.
484 * Use the value returned by this function with the MEDIATYPE_xxx constants.
485 * Overridden by LocalFile,
486 * STUB
487 */
488 function getMediaType() {
489 return MEDIATYPE_UNKNOWN;
490 }
491
492 /**
493 * Checks if the output of transform() for this file is likely
494 * to be valid. If this is false, various user elements will
495 * display a placeholder instead.
496 *
497 * Currently, this checks if the file is an image format
498 * that can be converted to a format
499 * supported by all browsers (namely GIF, PNG and JPEG),
500 * or if it is an SVG image and SVG conversion is enabled.
501 *
502 * @return bool
503 */
504 function canRender() {
505 if ( !isset( $this->canRender ) ) {
506 $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
507 }
508 return $this->canRender;
509 }
510
511 /**
512 * Accessor for __get()
513 */
514 protected function getCanRender() {
515 return $this->canRender();
516 }
517
518 /**
519 * Return true if the file is of a type that can't be directly
520 * rendered by typical browsers and needs to be re-rasterized.
521 *
522 * This returns true for everything but the bitmap types
523 * supported by all browsers, i.e. JPEG; GIF and PNG. It will
524 * also return true for any non-image formats.
525 *
526 * @return bool
527 */
528 function mustRender() {
529 return $this->getHandler() && $this->handler->mustRender( $this );
530 }
531
532 /**
533 * Alias for canRender()
534 *
535 * @return bool
536 */
537 function allowInlineDisplay() {
538 return $this->canRender();
539 }
540
541 /**
542 * Determines if this media file is in a format that is unlikely to
543 * contain viruses or malicious content. It uses the global
544 * $wgTrustedMediaFormats list to determine if the file is safe.
545 *
546 * This is used to show a warning on the description page of non-safe files.
547 * It may also be used to disallow direct [[media:...]] links to such files.
548 *
549 * Note that this function will always return true if allowInlineDisplay()
550 * or isTrustedFile() is true for this file.
551 *
552 * @return bool
553 */
554 function isSafeFile() {
555 if ( !isset( $this->isSafeFile ) ) {
556 $this->isSafeFile = $this->_getIsSafeFile();
557 }
558 return $this->isSafeFile;
559 }
560
561 /**
562 * Accessor for __get()
563 *
564 * @return bool
565 */
566 protected function getIsSafeFile() {
567 return $this->isSafeFile();
568 }
569
570 /**
571 * Uncached accessor
572 *
573 * @return bool
574 */
575 protected function _getIsSafeFile() {
576 global $wgTrustedMediaFormats;
577
578 if ( $this->allowInlineDisplay() ) {
579 return true;
580 }
581 if ($this->isTrustedFile()) {
582 return true;
583 }
584
585 $type = $this->getMediaType();
586 $mime = $this->getMimeType();
587 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
588
589 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
590 return false; #unknown type, not trusted
591 }
592 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
593 return true;
594 }
595
596 if ( $mime === "unknown/unknown" ) {
597 return false; #unknown type, not trusted
598 }
599 if ( in_array( $mime, $wgTrustedMediaFormats) ) {
600 return true;
601 }
602
603 return false;
604 }
605
606 /**
607 * Returns true if the file is flagged as trusted. Files flagged that way
608 * can be linked to directly, even if that is not allowed for this type of
609 * file normally.
610 *
611 * This is a dummy function right now and always returns false. It could be
612 * implemented to extract a flag from the database. The trusted flag could be
613 * set on upload, if the user has sufficient privileges, to bypass script-
614 * and html-filters. It may even be coupled with cryptographics signatures
615 * or such.
616 *
617 * @return bool
618 */
619 function isTrustedFile() {
620 #this could be implemented to check a flag in the database,
621 #look for signatures, etc
622 return false;
623 }
624
625 /**
626 * Returns true if file exists in the repository.
627 *
628 * Overridden by LocalFile to avoid unnecessary stat calls.
629 *
630 * @return boolean Whether file exists in the repository.
631 */
632 public function exists() {
633 return $this->getPath() && $this->repo->fileExists( $this->path );
634 }
635
636 /**
637 * Returns true if file exists in the repository and can be included in a page.
638 * It would be unsafe to include private images, making public thumbnails inadvertently
639 *
640 * @return boolean Whether file exists in the repository and is includable.
641 */
642 public function isVisible() {
643 return $this->exists();
644 }
645
646 /**
647 * @return string
648 */
649 function getTransformScript() {
650 if ( !isset( $this->transformScript ) ) {
651 $this->transformScript = false;
652 if ( $this->repo ) {
653 $script = $this->repo->getThumbScriptUrl();
654 if ( $script ) {
655 $this->transformScript = "$script?f=" . urlencode( $this->getName() );
656 }
657 }
658 }
659 return $this->transformScript;
660 }
661
662 /**
663 * Get a ThumbnailImage which is the same size as the source
664 *
665 * @param $handlerParams array
666 *
667 * @return string
668 */
669 function getUnscaledThumb( $handlerParams = array() ) {
670 $hp =& $handlerParams;
671 $page = isset( $hp['page'] ) ? $hp['page'] : false;
672 $width = $this->getWidth( $page );
673 if ( !$width ) {
674 return $this->iconThumb();
675 }
676 $hp['width'] = $width;
677 return $this->transform( $hp );
678 }
679
680 /**
681 * Return the file name of a thumbnail with the specified parameters
682 *
683 * @param $params Array: handler-specific parameters
684 * @private -ish
685 *
686 * @return string
687 */
688 function thumbName( $params ) {
689 return $this->generateThumbName( $this->getName(), $params );
690 }
691
692 /**
693 * Generate a thumbnail file name from a name and specified parameters
694 *
695 * @param string $name
696 * @param array $params Parameters which will be passed to MediaHandler::makeParamString
697 *
698 * @return string
699 */
700 function generateThumbName( $name, $params ) {
701 if ( !$this->getHandler() ) {
702 return null;
703 }
704 $extension = $this->getExtension();
705 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType(
706 $extension, $this->getMimeType(), $params );
707 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
708 if ( $thumbExt != $extension ) {
709 $thumbName .= ".$thumbExt";
710 }
711 return $thumbName;
712 }
713
714 /**
715 * Create a thumbnail of the image having the specified width/height.
716 * The thumbnail will not be created if the width is larger than the
717 * image's width. Let the browser do the scaling in this case.
718 * The thumbnail is stored on disk and is only computed if the thumbnail
719 * file does not exist OR if it is older than the image.
720 * Returns the URL.
721 *
722 * Keeps aspect ratio of original image. If both width and height are
723 * specified, the generated image will be no bigger than width x height,
724 * and will also have correct aspect ratio.
725 *
726 * @param $width Integer: maximum width of the generated thumbnail
727 * @param $height Integer: maximum height of the image (optional)
728 *
729 * @return string
730 */
731 public function createThumb( $width, $height = -1 ) {
732 $params = array( 'width' => $width );
733 if ( $height != -1 ) {
734 $params['height'] = $height;
735 }
736 $thumb = $this->transform( $params );
737 if ( is_null( $thumb ) || $thumb->isError() ) {
738 return '';
739 }
740 return $thumb->getUrl();
741 }
742
743 /**
744 * Do the work of a transform (from an original into a thumb).
745 * Contains filesystem-specific functions.
746 *
747 * @param $thumbName string: the name of the thumbnail file.
748 * @param $thumbUrl string: the URL of the thumbnail file.
749 * @param $params Array: an associative array of handler-specific parameters.
750 * Typical keys are width, height and page.
751 * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
752 *
753 * @return MediaTransformOutput|null
754 */
755 protected function maybeDoTransform( $thumbName, $thumbUrl, $params, $flags = 0 ) {
756 global $wgIgnoreImageErrors, $wgThumbnailEpoch;
757
758 $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
759
760 if ( $this->repo && $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
761 wfDebug( __METHOD__ . " transformation deferred." );
762 return $this->handler->getTransform( $this, false, $thumbUrl, $params );
763 }
764
765 wfDebug( __METHOD__.": Doing stat for $thumbPath\n" );
766 $this->migrateThumbFile( $thumbName );
767 if ( $this->repo->fileExists( $thumbPath ) && !( $flags & self::RENDER_FORCE ) ) {
768 $timestamp = $this->repo->getFileTimestamp( $thumbPath );
769 if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
770 return $this->handler->getTransform( $this, false, $thumbUrl, $params );
771 }
772 } elseif ( $flags & self::RENDER_FORCE ) {
773 wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
774 }
775
776 // Create a temp FS file with the same extension
777 $tmpFile = TempFSFile::factory( 'transform_', $this->getExtension() );
778 if ( !$tmpFile ) {
779 return new MediaTransformError( 'thumbnail_error',
780 $params['width'], 0, wfMsg( 'thumbnail-temp-create' ) );
781 }
782 $tmpThumbPath = $tmpFile->getPath(); // path of 0-byte temp file
783
784 // Actually render the thumbnail
785 $thumb = $this->handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $params );
786 $tmpFile->bind( $thumb ); // keep alive with $thumb
787
788 // Ignore errors if requested
789 if ( !$thumb ) {
790 $thumb = null;
791 } elseif ( $thumb->isError() ) {
792 $this->lastError = $thumb->toText();
793 if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
794 $thumb = $this->handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $params );
795 }
796 } elseif ( $thumb->hasFile() && !$thumb->fileIsSource() ) {
797 // @TODO: use a FileRepo store function
798 $op = array( 'op' => 'store',
799 'src' => $tmpThumbPath, 'dst' => $thumbPath, 'overwriteDest' => true );
800 // Copy any thumbnail from the FS into storage at $dstpath
801 $opts = array( 'ignoreErrors' => true, 'nonLocking' => true ); // performance
802 if ( !$this->getRepo()->getBackend()->doOperation( $op, $opts )->isOK() ) {
803 return new MediaTransformError( 'thumbnail_error',
804 $params['width'], 0, wfMsg( 'thumbnail-dest-create' ) );
805 }
806 }
807
808 return $thumb;
809 }
810
811 /**
812 * Transform a media file
813 *
814 * @param $params Array: an associative array of handler-specific parameters.
815 * Typical keys are width, height and page.
816 * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
817 * @return MediaTransformOutput | false
818 */
819 function transform( $params, $flags = 0 ) {
820 global $wgUseSquid;
821
822 wfProfileIn( __METHOD__ );
823 do {
824 if ( !$this->canRender() ) {
825 // not a bitmap or renderable image, don't try.
826 $thumb = $this->iconThumb();
827 break;
828 }
829
830 // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
831 $descriptionUrl = $this->getDescriptionUrl();
832 if ( $descriptionUrl ) {
833 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
834 }
835
836 $script = $this->getTransformScript();
837 if ( $script && !($flags & self::RENDER_NOW) ) {
838 // Use a script to transform on client request, if possible
839 $thumb = $this->handler->getScriptedTransform( $this, $script, $params );
840 if( $thumb ) {
841 break;
842 }
843 }
844
845 $normalisedParams = $params;
846 $this->handler->normaliseParams( $this, $normalisedParams );
847 $thumbName = $this->thumbName( $normalisedParams );
848 $thumbUrl = $this->getThumbUrl( $thumbName );
849
850 $thumb = $this->maybeDoTransform( $thumbName, $thumbUrl, $params, $flags );
851
852 // Purge. Useful in the event of Core -> Squid connection failure or squid
853 // purge collisions from elsewhere during failure. Don't keep triggering for
854 // "thumbs" which have the main image URL though (bug 13776)
855 if ( $wgUseSquid ) {
856 if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
857 SquidUpdate::purge( array( $thumbUrl ) );
858 }
859 }
860 } while (false);
861
862 wfProfileOut( __METHOD__ );
863 return is_object( $thumb ) ? $thumb : false;
864 }
865
866 /**
867 * Hook into transform() to allow migration of thumbnail files
868 * STUB
869 * Overridden by LocalFile
870 */
871 function migrateThumbFile( $thumbName ) {}
872
873 /**
874 * Get a MediaHandler instance for this file
875 *
876 * @return MediaHandler
877 */
878 function getHandler() {
879 if ( !isset( $this->handler ) ) {
880 $this->handler = MediaHandler::getHandler( $this->getMimeType() );
881 }
882 return $this->handler;
883 }
884
885 /**
886 * Get a ThumbnailImage representing a file type icon
887 *
888 * @return ThumbnailImage
889 */
890 function iconThumb() {
891 global $wgStylePath, $wgStyleDirectory;
892
893 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
894 foreach ( $try as $icon ) {
895 $path = '/common/images/icons/' . $icon;
896 $filepath = $wgStyleDirectory . $path;
897 if ( file_exists( $filepath ) ) { // always FS
898 return new ThumbnailImage( $this, $wgStylePath . $path, 120, 120 );
899 }
900 }
901 return null;
902 }
903
904 /**
905 * Get last thumbnailing error.
906 * Largely obsolete.
907 */
908 function getLastError() {
909 return $this->lastError;
910 }
911
912 /**
913 * Get all thumbnail names previously generated for this file
914 * STUB
915 * Overridden by LocalFile
916 */
917 function getThumbnails() {
918 return array();
919 }
920
921 /**
922 * Purge shared caches such as thumbnails and DB data caching
923 * STUB
924 * Overridden by LocalFile
925 * @param $options Array Options, which include:
926 * 'forThumbRefresh' : The purging is only to refresh thumbnails
927 */
928 function purgeCache( $options = array() ) {}
929
930 /**
931 * Purge the file description page, but don't go after
932 * pages using the file. Use when modifying file history
933 * but not the current data.
934 */
935 function purgeDescription() {
936 $title = $this->getTitle();
937 if ( $title ) {
938 $title->invalidateCache();
939 $title->purgeSquid();
940 }
941 }
942
943 /**
944 * Purge metadata and all affected pages when the file is created,
945 * deleted, or majorly updated.
946 */
947 function purgeEverything() {
948 // Delete thumbnails and refresh file metadata cache
949 $this->purgeCache();
950 $this->purgeDescription();
951
952 // Purge cache of all pages using this file
953 $title = $this->getTitle();
954 if ( $title ) {
955 $update = new HTMLCacheUpdate( $title, 'imagelinks' );
956 $update->doUpdate();
957 }
958 }
959
960 /**
961 * Return a fragment of the history of file.
962 *
963 * STUB
964 * @param $limit integer Limit of rows to return
965 * @param $start timestamp Only revisions older than $start will be returned
966 * @param $end timestamp Only revisions newer than $end will be returned
967 * @param $inc bool Include the endpoints of the time range
968 *
969 * @return array
970 */
971 function getHistory($limit = null, $start = null, $end = null, $inc=true) {
972 return array();
973 }
974
975 /**
976 * Return the history of this file, line by line. Starts with current version,
977 * then old versions. Should return an object similar to an image/oldimage
978 * database row.
979 *
980 * STUB
981 * Overridden in LocalFile
982 */
983 public function nextHistoryLine() {
984 return false;
985 }
986
987 /**
988 * Reset the history pointer to the first element of the history.
989 * Always call this function after using nextHistoryLine() to free db resources
990 * STUB
991 * Overridden in LocalFile.
992 */
993 public function resetHistory() {}
994
995 /**
996 * Get the filename hash component of the directory including trailing slash,
997 * e.g. f/fa/
998 * If the repository is not hashed, returns an empty string.
999 *
1000 * @return string
1001 */
1002 function getHashPath() {
1003 if ( !isset( $this->hashPath ) ) {
1004 $this->assertRepoDefined();
1005 $this->hashPath = $this->repo->getHashPath( $this->getName() );
1006 }
1007 return $this->hashPath;
1008 }
1009
1010 /**
1011 * Get the path of the file relative to the public zone root
1012 *
1013 * @return string
1014 */
1015 function getRel() {
1016 return $this->getHashPath() . $this->getName();
1017 }
1018
1019 /**
1020 * Get urlencoded relative path of the file
1021 *
1022 * @return string
1023 */
1024 function getUrlRel() {
1025 return $this->getHashPath() . rawurlencode( $this->getName() );
1026 }
1027
1028 /**
1029 * Get the relative path for an archived file
1030 *
1031 * @param $suffix bool|string if not false, the name of an archived thumbnail file
1032 *
1033 * @return string
1034 */
1035 function getArchiveRel( $suffix = false ) {
1036 $path = 'archive/' . $this->getHashPath();
1037 if ( $suffix === false ) {
1038 $path = substr( $path, 0, -1 );
1039 } else {
1040 $path .= $suffix;
1041 }
1042 return $path;
1043 }
1044
1045 /**
1046 * Get the relative path for an archived file's thumbs directory
1047 * or a specific thumb if the $suffix is given.
1048 *
1049 * @param $archiveName string the timestamped name of an archived image
1050 * @param $suffix bool|string if not false, the name of a thumbnail file
1051 *
1052 * @return string
1053 */
1054 function getArchiveThumbRel( $archiveName, $suffix = false ) {
1055 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1056 if ( $suffix === false ) {
1057 $path = substr( $path, 0, -1 );
1058 } else {
1059 $path .= $suffix;
1060 }
1061 return $path;
1062 }
1063
1064 /**
1065 * Get the path of the archived file.
1066 *
1067 * @param $suffix bool|string if not false, the name of an archived file.
1068 *
1069 * @return string
1070 */
1071 function getArchivePath( $suffix = false ) {
1072 $this->assertRepoDefined();
1073 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1074 }
1075
1076 /**
1077 * Get the path of the archived file's thumbs, or a particular thumb if $suffix is specified
1078 *
1079 * @param $archiveName string the timestamped name of an archived image
1080 * @param $suffix bool|string if not false, the name of a thumbnail file
1081 *
1082 * @return string
1083 */
1084 function getArchiveThumbPath( $archiveName, $suffix = false ) {
1085 $this->assertRepoDefined();
1086 return $this->repo->getZonePath( 'thumb' ) . '/' .
1087 $this->getArchiveThumbRel( $archiveName, $suffix );
1088 }
1089
1090 /**
1091 * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1092 *
1093 * @param $suffix bool|string if not false, the name of a thumbnail file
1094 *
1095 * @return string
1096 */
1097 function getThumbPath( $suffix = false ) {
1098 $this->assertRepoDefined();
1099 $path = $this->repo->getZonePath( 'thumb' ) . '/' . $this->getRel();
1100 if ( $suffix !== false ) {
1101 $path .= '/' . $suffix;
1102 }
1103 return $path;
1104 }
1105
1106 /**
1107 * Get the URL of the archive directory, or a particular file if $suffix is specified
1108 *
1109 * @param $suffix bool|string if not false, the name of an archived file
1110 *
1111 * @return string
1112 */
1113 function getArchiveUrl( $suffix = false ) {
1114 $this->assertRepoDefined();
1115 $path = $this->repo->getZoneUrl( 'public' ) . '/archive/' . $this->getHashPath();
1116 if ( $suffix === false ) {
1117 $path = substr( $path, 0, -1 );
1118 } else {
1119 $path .= rawurlencode( $suffix );
1120 }
1121 return $path;
1122 }
1123
1124 /**
1125 * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1126 *
1127 * @param $archiveName string the timestamped name of an archived image
1128 * @param $suffix bool|string if not false, the name of a thumbnail file
1129 *
1130 * @return string
1131 */
1132 function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1133 $this->assertRepoDefined();
1134 $path = $this->repo->getZoneUrl( 'thumb' ) . '/archive/' .
1135 $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1136 if ( $suffix === false ) {
1137 $path = substr( $path, 0, -1 );
1138 } else {
1139 $path .= rawurlencode( $suffix );
1140 }
1141 return $path;
1142 }
1143
1144 /**
1145 * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1146 *
1147 * @param $suffix bool|string if not false, the name of a thumbnail file
1148 *
1149 * @return path
1150 */
1151 function getThumbUrl( $suffix = false ) {
1152 $this->assertRepoDefined();
1153 $path = $this->repo->getZoneUrl( 'thumb' ) . '/' . $this->getUrlRel();
1154 if ( $suffix !== false ) {
1155 $path .= '/' . rawurlencode( $suffix );
1156 }
1157 return $path;
1158 }
1159
1160 /**
1161 * Get the public zone virtual URL for a current version source file
1162 *
1163 * @param $suffix bool|string if not false, the name of a thumbnail file
1164 *
1165 * @return string
1166 */
1167 function getVirtualUrl( $suffix = false ) {
1168 $this->assertRepoDefined();
1169 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1170 if ( $suffix !== false ) {
1171 $path .= '/' . rawurlencode( $suffix );
1172 }
1173 return $path;
1174 }
1175
1176 /**
1177 * Get the public zone virtual URL for an archived version source file
1178 *
1179 * @param $suffix bool|string if not false, the name of a thumbnail file
1180 *
1181 * @return string
1182 */
1183 function getArchiveVirtualUrl( $suffix = false ) {
1184 $this->assertRepoDefined();
1185 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1186 if ( $suffix === false ) {
1187 $path = substr( $path, 0, -1 );
1188 } else {
1189 $path .= rawurlencode( $suffix );
1190 }
1191 return $path;
1192 }
1193
1194 /**
1195 * Get the virtual URL for a thumbnail file or directory
1196 *
1197 * @param $suffix bool|string if not false, the name of a thumbnail file
1198 *
1199 * @return string
1200 */
1201 function getThumbVirtualUrl( $suffix = false ) {
1202 $this->assertRepoDefined();
1203 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1204 if ( $suffix !== false ) {
1205 $path .= '/' . rawurlencode( $suffix );
1206 }
1207 return $path;
1208 }
1209
1210 /**
1211 * @return bool
1212 */
1213 function isHashed() {
1214 $this->assertRepoDefined();
1215 return $this->repo->isHashed();
1216 }
1217
1218 /**
1219 * @throws MWException
1220 */
1221 function readOnlyError() {
1222 throw new MWException( get_class($this) . ': write operations are not supported' );
1223 }
1224
1225 /**
1226 * Record a file upload in the upload log and the image table
1227 * STUB
1228 * Overridden by LocalFile
1229 * @param $oldver
1230 * @param $desc
1231 * @param $license string
1232 * @param $copyStatus string
1233 * @param $source string
1234 * @param $watch bool
1235 */
1236 function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
1237 $this->readOnlyError();
1238 }
1239
1240 /**
1241 * Move or copy a file to its public location. If a file exists at the
1242 * destination, move it to an archive. Returns a FileRepoStatus object with
1243 * the archive name in the "value" member on success.
1244 *
1245 * The archive name should be passed through to recordUpload for database
1246 * registration.
1247 *
1248 * @param $srcPath String: local filesystem path to the source image
1249 * @param $flags Integer: a bitwise combination of:
1250 * File::DELETE_SOURCE Delete the source file, i.e. move
1251 * rather than copy
1252 * @return FileRepoStatus object. On success, the value member contains the
1253 * archive name, or an empty string if it was a new file.
1254 *
1255 * STUB
1256 * Overridden by LocalFile
1257 */
1258 function publish( $srcPath, $flags = 0 ) {
1259 $this->readOnlyError();
1260 }
1261
1262 /**
1263 * @return bool
1264 */
1265 function formatMetadata() {
1266 if ( !$this->getHandler() ) {
1267 return false;
1268 }
1269 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1270 }
1271
1272 /**
1273 * Returns true if the file comes from the local file repository.
1274 *
1275 * @return bool
1276 */
1277 function isLocal() {
1278 $repo = $this->getRepo();
1279 return $repo && $repo->isLocal();
1280 }
1281
1282 /**
1283 * Returns the name of the repository.
1284 *
1285 * @return string
1286 */
1287 function getRepoName() {
1288 return $this->repo ? $this->repo->getName() : 'unknown';
1289 }
1290
1291 /**
1292 * Returns the repository
1293 *
1294 * @return FileRepo|false
1295 */
1296 function getRepo() {
1297 return $this->repo;
1298 }
1299
1300 /**
1301 * Returns true if the image is an old version
1302 * STUB
1303 *
1304 * @return bool
1305 */
1306 function isOld() {
1307 return false;
1308 }
1309
1310 /**
1311 * Is this file a "deleted" file in a private archive?
1312 * STUB
1313 *
1314 * @param $field
1315 *
1316 * @return bool
1317 */
1318 function isDeleted( $field ) {
1319 return false;
1320 }
1321
1322 /**
1323 * Return the deletion bitfield
1324 * STUB
1325 */
1326 function getVisibility() {
1327 return 0;
1328 }
1329
1330 /**
1331 * Was this file ever deleted from the wiki?
1332 *
1333 * @return bool
1334 */
1335 function wasDeleted() {
1336 $title = $this->getTitle();
1337 return $title && $title->isDeletedQuick();
1338 }
1339
1340 /**
1341 * Move file to the new title
1342 *
1343 * Move current, old version and all thumbnails
1344 * to the new filename. Old file is deleted.
1345 *
1346 * Cache purging is done; checks for validity
1347 * and logging are caller's responsibility
1348 *
1349 * @param $target Title New file name
1350 * @return FileRepoStatus object.
1351 */
1352 function move( $target ) {
1353 $this->readOnlyError();
1354 }
1355
1356 /**
1357 * Delete all versions of the file.
1358 *
1359 * Moves the files into an archive directory (or deletes them)
1360 * and removes the database rows.
1361 *
1362 * Cache purging is done; logging is caller's responsibility.
1363 *
1364 * @param $reason String
1365 * @param $suppress Boolean: hide content from sysops?
1366 * @return true on success, false on some kind of failure
1367 * STUB
1368 * Overridden by LocalFile
1369 */
1370 function delete( $reason, $suppress = false ) {
1371 $this->readOnlyError();
1372 }
1373
1374 /**
1375 * Restore all or specified deleted revisions to the given file.
1376 * Permissions and logging are left to the caller.
1377 *
1378 * May throw database exceptions on error.
1379 *
1380 * @param $versions array set of record ids of deleted items to restore,
1381 * or empty to restore all revisions.
1382 * @param $unsuppress bool remove restrictions on content upon restoration?
1383 * @return int|false the number of file revisions restored if successful,
1384 * or false on failure
1385 * STUB
1386 * Overridden by LocalFile
1387 */
1388 function restore( $versions = array(), $unsuppress = false ) {
1389 $this->readOnlyError();
1390 }
1391
1392 /**
1393 * Returns 'true' if this file is a type which supports multiple pages,
1394 * e.g. DJVU or PDF. Note that this may be true even if the file in
1395 * question only has a single page.
1396 *
1397 * @return Bool
1398 */
1399 function isMultipage() {
1400 return $this->getHandler() && $this->handler->isMultiPage( $this );
1401 }
1402
1403 /**
1404 * Returns the number of pages of a multipage document, or false for
1405 * documents which aren't multipage documents
1406 *
1407 * @return false|int
1408 */
1409 function pageCount() {
1410 if ( !isset( $this->pageCount ) ) {
1411 if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1412 $this->pageCount = $this->handler->pageCount( $this );
1413 } else {
1414 $this->pageCount = false;
1415 }
1416 }
1417 return $this->pageCount;
1418 }
1419
1420 /**
1421 * Calculate the height of a thumbnail using the source and destination width
1422 *
1423 * @param $srcWidth
1424 * @param $srcHeight
1425 * @param $dstWidth
1426 *
1427 * @return int
1428 */
1429 static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1430 // Exact integer multiply followed by division
1431 if ( $srcWidth == 0 ) {
1432 return 0;
1433 } else {
1434 return round( $srcHeight * $dstWidth / $srcWidth );
1435 }
1436 }
1437
1438 /**
1439 * Get an image size array like that returned by getImageSize(), or false if it
1440 * can't be determined.
1441 *
1442 * @param $fileName String: The filename
1443 * @return Array
1444 */
1445 function getImageSize( $fileName ) {
1446 if ( !$this->getHandler() ) {
1447 return false;
1448 }
1449 return $this->handler->getImageSize( $this, $fileName );
1450 }
1451
1452 /**
1453 * Get the URL of the image description page. May return false if it is
1454 * unknown or not applicable.
1455 *
1456 * @return string
1457 */
1458 function getDescriptionUrl() {
1459 if ( $this->repo ) {
1460 return $this->repo->getDescriptionUrl( $this->getName() );
1461 } else {
1462 return false;
1463 }
1464 }
1465
1466 /**
1467 * Get the HTML text of the description page, if available
1468 *
1469 * @return string
1470 */
1471 function getDescriptionText() {
1472 global $wgMemc, $wgLang;
1473 if ( !$this->repo || !$this->repo->fetchDescription ) {
1474 return false;
1475 }
1476 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1477 if ( $renderUrl ) {
1478 if ( $this->repo->descriptionCacheExpiry > 0 ) {
1479 wfDebug("Attempting to get the description from cache...");
1480 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1481 $this->getName() );
1482 $obj = $wgMemc->get($key);
1483 if ($obj) {
1484 wfDebug("success!\n");
1485 return $obj;
1486 }
1487 wfDebug("miss\n");
1488 }
1489 wfDebug( "Fetching shared description from $renderUrl\n" );
1490 $res = Http::get( $renderUrl );
1491 if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1492 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1493 }
1494 return $res;
1495 } else {
1496 return false;
1497 }
1498 }
1499
1500 /**
1501 * Get discription of file revision
1502 * STUB
1503 *
1504 * @return string
1505 */
1506 function getDescription() {
1507 return null;
1508 }
1509
1510 /**
1511 * Get the 14-character timestamp of the file upload
1512 *
1513 * @return string|false TS_MW timestamp or false on failure
1514 */
1515 function getTimestamp() {
1516 $this->assertRepoDefined();
1517 return $this->repo->getFileTimestamp( $this->getPath() );
1518 }
1519
1520 /**
1521 * Get the SHA-1 base 36 hash of the file
1522 *
1523 * @return string
1524 */
1525 function getSha1() {
1526 $this->assertRepoDefined();
1527 return $this->repo->getFileSha1( $this->getPath() );
1528 }
1529
1530 /**
1531 * Get the deletion archive key, <sha1>.<ext>
1532 *
1533 * @return string
1534 */
1535 function getStorageKey() {
1536 $hash = $this->getSha1();
1537 if ( !$hash ) {
1538 return false;
1539 }
1540 $ext = $this->getExtension();
1541 $dotExt = $ext === '' ? '' : ".$ext";
1542 return $hash . $dotExt;
1543 }
1544
1545 /**
1546 * Determine if the current user is allowed to view a particular
1547 * field of this file, if it's marked as deleted.
1548 * STUB
1549 * @param $field Integer
1550 * @param $user User object to check, or null to use $wgUser
1551 * @return Boolean
1552 */
1553 function userCan( $field, User $user = null ) {
1554 return true;
1555 }
1556
1557 /**
1558 * Get an associative array containing information about a file in the local filesystem.
1559 *
1560 * @param $path String: absolute local filesystem path
1561 * @param $ext Mixed: the file extension, or true to extract it from the filename.
1562 * Set it to false to ignore the extension.
1563 *
1564 * @return array
1565 */
1566 static function getPropsFromPath( $path, $ext = true ) {
1567 wfDebug( __METHOD__.": Getting file info for $path\n" );
1568 wfDeprecated( __METHOD__, '1.19' );
1569
1570 $fsFile = new FSFile( $path );
1571 return $fsFile->getProps();
1572 }
1573
1574 /**
1575 * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1576 * encoding, zero padded to 31 digits.
1577 *
1578 * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1579 * fairly neatly.
1580 *
1581 * @param $path string
1582 *
1583 * @return false|string False on failure
1584 */
1585 static function sha1Base36( $path ) {
1586 wfDeprecated( __METHOD__, '1.19' );
1587
1588 $fsFile = new FSFile( $path );
1589 return $fsFile->getSha1Base36();
1590 }
1591
1592 /**
1593 * @return string
1594 */
1595 function getLongDesc() {
1596 $handler = $this->getHandler();
1597 if ( $handler ) {
1598 return $handler->getLongDesc( $this );
1599 } else {
1600 return MediaHandler::getGeneralLongDesc( $this );
1601 }
1602 }
1603
1604 /**
1605 * @return string
1606 */
1607 function getShortDesc() {
1608 $handler = $this->getHandler();
1609 if ( $handler ) {
1610 return $handler->getShortDesc( $this );
1611 } else {
1612 return MediaHandler::getGeneralShortDesc( $this );
1613 }
1614 }
1615
1616 /**
1617 * @return string
1618 */
1619 function getDimensionsString() {
1620 $handler = $this->getHandler();
1621 if ( $handler ) {
1622 return $handler->getDimensionsString( $this );
1623 } else {
1624 return '';
1625 }
1626 }
1627
1628 /**
1629 * @return
1630 */
1631 function getRedirected() {
1632 return $this->redirected;
1633 }
1634
1635 /**
1636 * @return Title
1637 */
1638 function getRedirectedTitle() {
1639 if ( $this->redirected ) {
1640 if ( !$this->redirectTitle ) {
1641 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1642 }
1643 return $this->redirectTitle;
1644 }
1645 }
1646
1647 /**
1648 * @param $from
1649 * @return void
1650 */
1651 function redirectedFrom( $from ) {
1652 $this->redirected = $from;
1653 }
1654
1655 /**
1656 * @return bool
1657 */
1658 function isMissing() {
1659 return false;
1660 }
1661
1662 /**
1663 * Assert that $this->repo is set to a valid FileRepo instance
1664 * @throws MWException
1665 */
1666 protected function assertRepoDefined() {
1667 if ( !( $this->repo instanceof $this->repoClass ) ) {
1668 throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
1669 }
1670 }
1671
1672 /**
1673 * Assert that $this->title is set to a Title
1674 * @throws MWException
1675 */
1676 protected function assertTitleDefined() {
1677 if ( !( $this->title instanceof Title ) ) {
1678 throw new MWException( "A Title object is not set for this File.\n" );
1679 }
1680 }
1681 }