Remove unused variable in ProfilerMwprof
[mediawiki.git] / includes / content / ContentHandler.php
blobac417223075ff12a7954345b547c00dd51bb4808
1 <?php
2 /**
3 * Base class for content handling.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
20 * @since 1.21
22 * @file
23 * @ingroup Content
25 * @author Daniel Kinzler
28 /**
29 * Exception representing a failure to serialize or unserialize a content object.
31 * @ingroup Content
33 class MWContentSerializationException extends MWException {
36 /**
37 * A content handler knows how do deal with a specific type of content on a wiki
38 * page. Content is stored in the database in a serialized form (using a
39 * serialization format a.k.a. MIME type) and is unserialized into its native
40 * PHP representation (the content model), which is wrapped in an instance of
41 * the appropriate subclass of Content.
43 * ContentHandler instances are stateless singletons that serve, among other
44 * things, as a factory for Content objects. Generally, there is one subclass
45 * of ContentHandler and one subclass of Content for every type of content model.
47 * Some content types have a flat model, that is, their native representation
48 * is the same as their serialized form. Examples would be JavaScript and CSS
49 * code. As of now, this also applies to wikitext (MediaWiki's default content
50 * type), but wikitext content may be represented by a DOM or AST structure in
51 * the future.
53 * @ingroup Content
55 abstract class ContentHandler {
56 /**
57 * Switch for enabling deprecation warnings. Used by ContentHandler::deprecated()
58 * and ContentHandler::runLegacyHooks().
60 * Once the ContentHandler code has settled in a bit, this should be set to true to
61 * make extensions etc. show warnings when using deprecated functions and hooks.
63 protected static $enableDeprecationWarnings = false;
65 /**
66 * Convenience function for getting flat text from a Content object. This
67 * should only be used in the context of backwards compatibility with code
68 * that is not yet able to handle Content objects!
70 * If $content is null, this method returns the empty string.
72 * If $content is an instance of TextContent, this method returns the flat
73 * text as returned by $content->getNativeData().
75 * If $content is not a TextContent object, the behavior of this method
76 * depends on the global $wgContentHandlerTextFallback:
77 * - If $wgContentHandlerTextFallback is 'fail' and $content is not a
78 * TextContent object, an MWException is thrown.
79 * - If $wgContentHandlerTextFallback is 'serialize' and $content is not a
80 * TextContent object, $content->serialize() is called to get a string
81 * form of the content.
82 * - If $wgContentHandlerTextFallback is 'ignore' and $content is not a
83 * TextContent object, this method returns null.
84 * - otherwise, the behavior is undefined.
86 * @since 1.21
88 * @param Content $content
90 * @throws MWException If the content is not an instance of TextContent and
91 * wgContentHandlerTextFallback was set to 'fail'.
92 * @return string|null Textual form of the content, if available.
94 public static function getContentText( Content $content = null ) {
95 global $wgContentHandlerTextFallback;
97 if ( is_null( $content ) ) {
98 return '';
101 if ( $content instanceof TextContent ) {
102 return $content->getNativeData();
105 wfDebugLog( 'ContentHandler', 'Accessing ' . $content->getModel() . ' content as text!' );
107 if ( $wgContentHandlerTextFallback == 'fail' ) {
108 throw new MWException(
109 "Attempt to get text from Content with model " .
110 $content->getModel()
114 if ( $wgContentHandlerTextFallback == 'serialize' ) {
115 return $content->serialize();
118 return null;
122 * Convenience function for creating a Content object from a given textual
123 * representation.
125 * $text will be deserialized into a Content object of the model specified
126 * by $modelId (or, if that is not given, $title->getContentModel()) using
127 * the given format.
129 * @since 1.21
131 * @param string $text The textual representation, will be
132 * unserialized to create the Content object
133 * @param Title $title The title of the page this text belongs to.
134 * Required if $modelId is not provided.
135 * @param string $modelId The model to deserialize to. If not provided,
136 * $title->getContentModel() is used.
137 * @param string $format The format to use for deserialization. If not
138 * given, the model's default format is used.
140 * @throws MWException If model ID or format is not supported or if the text can not be
141 * unserialized using the format.
142 * @return Content A Content object representing the text.
144 public static function makeContent( $text, Title $title = null,
145 $modelId = null, $format = null ) {
146 if ( is_null( $modelId ) ) {
147 if ( is_null( $title ) ) {
148 throw new MWException( "Must provide a Title object or a content model ID." );
151 $modelId = $title->getContentModel();
154 $handler = ContentHandler::getForModelID( $modelId );
156 return $handler->unserializeContent( $text, $format );
160 * Returns the name of the default content model to be used for the page
161 * with the given title.
163 * Note: There should rarely be need to call this method directly.
164 * To determine the actual content model for a given page, use
165 * Title::getContentModel().
167 * Which model is to be used by default for the page is determined based
168 * on several factors:
169 * - The global setting $wgNamespaceContentModels specifies a content model
170 * per namespace.
171 * - The hook ContentHandlerDefaultModelFor may be used to override the page's default
172 * model.
173 * - Pages in NS_MEDIAWIKI and NS_USER default to the CSS or JavaScript
174 * model if they end in .js or .css, respectively.
175 * - Pages in NS_MEDIAWIKI default to the wikitext model otherwise.
176 * - The hook TitleIsCssOrJsPage may be used to force a page to use the CSS
177 * or JavaScript model. This is a compatibility feature. The ContentHandlerDefaultModelFor
178 * hook should be used instead if possible.
179 * - The hook TitleIsWikitextPage may be used to force a page to use the
180 * wikitext model. This is a compatibility feature. The ContentHandlerDefaultModelFor
181 * hook should be used instead if possible.
183 * If none of the above applies, the wikitext model is used.
185 * Note: this is used by, and may thus not use, Title::getContentModel()
187 * @since 1.21
189 * @param Title $title
191 * @return string Default model name for the page given by $title
193 public static function getDefaultModelFor( Title $title ) {
194 // NOTE: this method must not rely on $title->getContentModel() directly or indirectly,
195 // because it is used to initialize the mContentModel member.
197 $ns = $title->getNamespace();
199 $ext = false;
200 $m = null;
201 $model = MWNamespace::getNamespaceContentModel( $ns );
203 // Hook can determine default model
204 if ( !wfRunHooks( 'ContentHandlerDefaultModelFor', array( $title, &$model ) ) ) {
205 if ( !is_null( $model ) ) {
206 return $model;
210 // Could this page contain custom CSS or JavaScript, based on the title?
211 $isCssOrJsPage = NS_MEDIAWIKI == $ns && preg_match( '!\.(css|js)$!u', $title->getText(), $m );
212 if ( $isCssOrJsPage ) {
213 $ext = $m[1];
216 // Hook can force JS/CSS
217 wfRunHooks( 'TitleIsCssOrJsPage', array( $title, &$isCssOrJsPage ) );
219 // Is this a .css subpage of a user page?
220 $isJsCssSubpage = NS_USER == $ns
221 && !$isCssOrJsPage
222 && preg_match( "/\\/.*\\.(js|css)$/", $title->getText(), $m );
223 if ( $isJsCssSubpage ) {
224 $ext = $m[1];
227 // Is this wikitext, according to $wgNamespaceContentModels or the DefaultModelFor hook?
228 $isWikitext = is_null( $model ) || $model == CONTENT_MODEL_WIKITEXT;
229 $isWikitext = $isWikitext && !$isCssOrJsPage && !$isJsCssSubpage;
231 // Hook can override $isWikitext
232 wfRunHooks( 'TitleIsWikitextPage', array( $title, &$isWikitext ) );
234 if ( !$isWikitext ) {
235 switch ( $ext ) {
236 case 'js':
237 return CONTENT_MODEL_JAVASCRIPT;
238 case 'css':
239 return CONTENT_MODEL_CSS;
240 default:
241 return is_null( $model ) ? CONTENT_MODEL_TEXT : $model;
245 // We established that it must be wikitext
247 return CONTENT_MODEL_WIKITEXT;
251 * Returns the appropriate ContentHandler singleton for the given title.
253 * @since 1.21
255 * @param Title $title
257 * @return ContentHandler
259 public static function getForTitle( Title $title ) {
260 $modelId = $title->getContentModel();
262 return ContentHandler::getForModelID( $modelId );
266 * Returns the appropriate ContentHandler singleton for the given Content
267 * object.
269 * @since 1.21
271 * @param Content $content
273 * @return ContentHandler
275 public static function getForContent( Content $content ) {
276 $modelId = $content->getModel();
278 return ContentHandler::getForModelID( $modelId );
282 * @var array A Cache of ContentHandler instances by model id
284 protected static $handlers;
287 * Returns the ContentHandler singleton for the given model ID. Use the
288 * CONTENT_MODEL_XXX constants to identify the desired content model.
290 * ContentHandler singletons are taken from the global $wgContentHandlers
291 * array. Keys in that array are model names, the values are either
292 * ContentHandler singleton objects, or strings specifying the appropriate
293 * subclass of ContentHandler.
295 * If a class name is encountered when looking up the singleton for a given
296 * model name, the class is instantiated and the class name is replaced by
297 * the resulting singleton in $wgContentHandlers.
299 * If no ContentHandler is defined for the desired $modelId, the
300 * ContentHandler may be provided by the ContentHandlerForModelID hook.
301 * If no ContentHandler can be determined, an MWException is raised.
303 * @since 1.21
305 * @param string $modelId The ID of the content model for which to get a
306 * handler. Use CONTENT_MODEL_XXX constants.
308 * @throws MWException If no handler is known for the model ID.
309 * @return ContentHandler The ContentHandler singleton for handling the model given by the ID.
311 public static function getForModelID( $modelId ) {
312 global $wgContentHandlers;
314 if ( isset( ContentHandler::$handlers[$modelId] ) ) {
315 return ContentHandler::$handlers[$modelId];
318 if ( empty( $wgContentHandlers[$modelId] ) ) {
319 $handler = null;
321 wfRunHooks( 'ContentHandlerForModelID', array( $modelId, &$handler ) );
323 if ( $handler === null ) {
324 throw new MWException( "No handler for model '$modelId' registered in \$wgContentHandlers" );
327 if ( !( $handler instanceof ContentHandler ) ) {
328 throw new MWException( "ContentHandlerForModelID must supply a ContentHandler instance" );
330 } else {
331 $class = $wgContentHandlers[$modelId];
332 $handler = new $class( $modelId );
334 if ( !( $handler instanceof ContentHandler ) ) {
335 throw new MWException( "$class from \$wgContentHandlers is not " .
336 "compatible with ContentHandler" );
340 wfDebugLog( 'ContentHandler', 'Created handler for ' . $modelId
341 . ': ' . get_class( $handler ) );
343 ContentHandler::$handlers[$modelId] = $handler;
345 return ContentHandler::$handlers[$modelId];
349 * Returns the localized name for a given content model.
351 * Model names are localized using system messages. Message keys
352 * have the form content-model-$name, where $name is getContentModelName( $id ).
354 * @param string $name The content model ID, as given by a CONTENT_MODEL_XXX
355 * constant or returned by Revision::getContentModel().
357 * @throws MWException If the model ID isn't known.
358 * @return string The content model's localized name.
360 public static function getLocalizedName( $name ) {
361 // Messages: content-model-wikitext, content-model-text,
362 // content-model-javascript, content-model-css
363 $key = "content-model-$name";
365 $msg = wfMessage( $key );
367 return $msg->exists() ? $msg->plain() : $name;
370 public static function getContentModels() {
371 global $wgContentHandlers;
373 return array_keys( $wgContentHandlers );
376 public static function getAllContentFormats() {
377 global $wgContentHandlers;
379 $formats = array();
381 foreach ( $wgContentHandlers as $model => $class ) {
382 $handler = ContentHandler::getForModelID( $model );
383 $formats = array_merge( $formats, $handler->getSupportedFormats() );
386 $formats = array_unique( $formats );
388 return $formats;
391 // ------------------------------------------------------------------------
394 * @var string
396 protected $mModelID;
399 * @var string[]
401 protected $mSupportedFormats;
404 * Constructor, initializing the ContentHandler instance with its model ID
405 * and a list of supported formats. Values for the parameters are typically
406 * provided as literals by subclass's constructors.
408 * @param string $modelId (use CONTENT_MODEL_XXX constants).
409 * @param string[] $formats List for supported serialization formats
410 * (typically as MIME types)
412 public function __construct( $modelId, $formats ) {
413 $this->mModelID = $modelId;
414 $this->mSupportedFormats = $formats;
416 $this->mModelName = preg_replace( '/(Content)?Handler$/', '', get_class( $this ) );
417 $this->mModelName = preg_replace( '/[_\\\\]/', '', $this->mModelName );
418 $this->mModelName = strtolower( $this->mModelName );
422 * Serializes a Content object of the type supported by this ContentHandler.
424 * @since 1.21
426 * @param Content $content The Content object to serialize
427 * @param string $format The desired serialization format
429 * @return string Serialized form of the content
431 abstract public function serializeContent( Content $content, $format = null );
434 * Applies transformations on export (returns the blob unchanged per default).
435 * Subclasses may override this to perform transformations such as conversion
436 * of legacy formats or filtering of internal meta-data.
438 * @param string $blob The blob to be exported
439 * @param string|null $format The blob's serialization format
441 * @return string
443 public function exportTransform( $blob, $format = null ) {
444 return $blob;
448 * Unserializes a Content object of the type supported by this ContentHandler.
450 * @since 1.21
452 * @param string $blob Serialized form of the content
453 * @param string $format The format used for serialization
455 * @return Content The Content object created by deserializing $blob
457 abstract public function unserializeContent( $blob, $format = null );
460 * Apply import transformation (per default, returns $blob unchanged).
461 * This gives subclasses an opportunity to transform data blobs on import.
463 * @since 1.24
465 * @param string $blob
466 * @param string|null $format
468 * @return string
470 public function importTransform( $blob, $format = null ) {
471 return $blob;
475 * Creates an empty Content object of the type supported by this
476 * ContentHandler.
478 * @since 1.21
480 * @return Content
482 abstract public function makeEmptyContent();
485 * Creates a new Content object that acts as a redirect to the given page,
486 * or null if redirects are not supported by this content model.
488 * This default implementation always returns null. Subclasses supporting redirects
489 * must override this method.
491 * Note that subclasses that override this method to return a Content object
492 * should also override supportsRedirects() to return true.
494 * @since 1.21
496 * @param Title $destination The page to redirect to.
497 * @param string $text Text to include in the redirect, if possible.
499 * @return Content Always null.
501 public function makeRedirectContent( Title $destination, $text = '' ) {
502 return null;
506 * Returns the model id that identifies the content model this
507 * ContentHandler can handle. Use with the CONTENT_MODEL_XXX constants.
509 * @since 1.21
511 * @return string The model ID
513 public function getModelID() {
514 return $this->mModelID;
518 * @since 1.21
520 * @param string $model_id The model to check
522 * @throws MWException If the model ID is not the ID of the content model supported by this
523 * ContentHandler.
525 protected function checkModelID( $model_id ) {
526 if ( $model_id !== $this->mModelID ) {
527 throw new MWException( "Bad content model: " .
528 "expected {$this->mModelID} " .
529 "but got $model_id." );
534 * Returns a list of serialization formats supported by the
535 * serializeContent() and unserializeContent() methods of this
536 * ContentHandler.
538 * @since 1.21
540 * @return string[] List of serialization formats as MIME type like strings
542 public function getSupportedFormats() {
543 return $this->mSupportedFormats;
547 * The format used for serialization/deserialization by default by this
548 * ContentHandler.
550 * This default implementation will return the first element of the array
551 * of formats that was passed to the constructor.
553 * @since 1.21
555 * @return string The name of the default serialization format as a MIME type
557 public function getDefaultFormat() {
558 return $this->mSupportedFormats[0];
562 * Returns true if $format is a serialization format supported by this
563 * ContentHandler, and false otherwise.
565 * Note that if $format is null, this method always returns true, because
566 * null means "use the default format".
568 * @since 1.21
570 * @param string $format The serialization format to check
572 * @return bool
574 public function isSupportedFormat( $format ) {
575 if ( !$format ) {
576 return true; // this means "use the default"
579 return in_array( $format, $this->mSupportedFormats );
583 * Convenient for checking whether a format provided as a parameter is actually supported.
585 * @param string $format The serialization format to check
587 * @throws MWException If the format is not supported by this content handler.
589 protected function checkFormat( $format ) {
590 if ( !$this->isSupportedFormat( $format ) ) {
591 throw new MWException(
592 "Format $format is not supported for content model "
593 . $this->getModelID()
599 * Returns overrides for action handlers.
600 * Classes listed here will be used instead of the default one when
601 * (and only when) $wgActions[$action] === true. This allows subclasses
602 * to override the default action handlers.
604 * @since 1.21
606 * @return array Always an empty array.
608 public function getActionOverrides() {
609 return array();
613 * Factory for creating an appropriate DifferenceEngine for this content model.
615 * @since 1.21
617 * @param IContextSource $context Context to use, anything else will be ignored.
618 * @param int $old Revision ID we want to show and diff with.
619 * @param int|string $new Either a revision ID or one of the strings 'cur', 'prev' or 'next'.
620 * @param int $rcid FIXME: Deprecated, no longer used. Defaults to 0.
621 * @param bool $refreshCache If set, refreshes the diff cache. Defaults to false.
622 * @param bool $unhide If set, allow viewing deleted revs. Defaults to false.
624 * @return DifferenceEngine
626 public function createDifferenceEngine( IContextSource $context, $old = 0, $new = 0,
627 $rcid = 0, //FIXME: Deprecated, no longer used
628 $refreshCache = false, $unhide = false ) {
629 $diffEngineClass = $this->getDiffEngineClass();
631 return new $diffEngineClass( $context, $old, $new, $rcid, $refreshCache, $unhide );
635 * Get the language in which the content of the given page is written.
637 * This default implementation just returns $wgContLang (except for pages
638 * in the MediaWiki namespace)
640 * Note that the pages language is not cacheable, since it may in some
641 * cases depend on user settings.
643 * Also note that the page language may or may not depend on the actual content of the page,
644 * that is, this method may load the content in order to determine the language.
646 * @since 1.21
648 * @param Title $title The page to determine the language for.
649 * @param Content $content The page's content, if you have it handy, to avoid reloading it.
651 * @return Language The page's language
653 public function getPageLanguage( Title $title, Content $content = null ) {
654 global $wgContLang, $wgLang;
655 $pageLang = $wgContLang;
657 if ( $title->getNamespace() == NS_MEDIAWIKI ) {
658 // Parse mediawiki messages with correct target language
659 list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $title->getText() );
660 $pageLang = wfGetLangObj( $lang );
663 wfRunHooks( 'PageContentLanguage', array( $title, &$pageLang, $wgLang ) );
665 return wfGetLangObj( $pageLang );
669 * Get the language in which the content of this page is written when
670 * viewed by user. Defaults to $this->getPageLanguage(), but if the user
671 * specified a preferred variant, the variant will be used.
673 * This default implementation just returns $this->getPageLanguage( $title, $content ) unless
674 * the user specified a preferred variant.
676 * Note that the pages view language is not cacheable, since it depends on user settings.
678 * Also note that the page language may or may not depend on the actual content of the page,
679 * that is, this method may load the content in order to determine the language.
681 * @since 1.21
683 * @param Title $title The page to determine the language for.
684 * @param Content $content The page's content, if you have it handy, to avoid reloading it.
686 * @return Language The page's language for viewing
688 public function getPageViewLanguage( Title $title, Content $content = null ) {
689 $pageLang = $this->getPageLanguage( $title, $content );
691 if ( $title->getNamespace() !== NS_MEDIAWIKI ) {
692 // If the user chooses a variant, the content is actually
693 // in a language whose code is the variant code.
694 $variant = $pageLang->getPreferredVariant();
695 if ( $pageLang->getCode() !== $variant ) {
696 $pageLang = Language::factory( $variant );
700 return $pageLang;
704 * Determines whether the content type handled by this ContentHandler
705 * can be used on the given page.
707 * This default implementation always returns true.
708 * Subclasses may override this to restrict the use of this content model to specific locations,
709 * typically based on the namespace or some other aspect of the title, such as a special suffix
710 * (e.g. ".svg" for SVG content).
712 * @note this calls the ContentHandlerCanBeUsedOn hook which may be used to override which
713 * content model can be used where.
715 * @param Title $title The page's title.
717 * @return bool True if content of this kind can be used on the given page, false otherwise.
719 public function canBeUsedOn( Title $title ) {
720 $ok = true;
722 wfRunHooks( 'ContentModelCanBeUsedOn', array( $this->getModelID(), $title, &$ok ) );
724 return $ok;
728 * Returns the name of the diff engine to use.
730 * @since 1.21
732 * @return string
734 protected function getDiffEngineClass() {
735 return 'DifferenceEngine';
739 * Attempts to merge differences between three versions. Returns a new
740 * Content object for a clean merge and false for failure or a conflict.
742 * This default implementation always returns false.
744 * @since 1.21
746 * @param Content $oldContent The page's previous content.
747 * @param Content $myContent One of the page's conflicting contents.
748 * @param Content $yourContent One of the page's conflicting contents.
750 * @return Content|bool Always false.
752 public function merge3( Content $oldContent, Content $myContent, Content $yourContent ) {
753 return false;
757 * Return an applicable auto-summary if one exists for the given edit.
759 * @since 1.21
761 * @param Content $oldContent The previous text of the page.
762 * @param Content $newContent The submitted text of the page.
763 * @param int $flags Bit mask: a bit mask of flags submitted for the edit.
765 * @return string An appropriate auto-summary, or an empty string.
767 public function getAutosummary( Content $oldContent = null, Content $newContent = null,
768 $flags ) {
769 // Decide what kind of auto-summary is needed.
771 // Redirect auto-summaries
774 * @var $ot Title
775 * @var $rt Title
778 $ot = !is_null( $oldContent ) ? $oldContent->getRedirectTarget() : null;
779 $rt = !is_null( $newContent ) ? $newContent->getRedirectTarget() : null;
781 if ( is_object( $rt ) ) {
782 if ( !is_object( $ot )
783 || !$rt->equals( $ot )
784 || $ot->getFragment() != $rt->getFragment()
786 $truncatedtext = $newContent->getTextForSummary(
788 - strlen( wfMessage( 'autoredircomment' )->inContentLanguage()->text() )
789 - strlen( $rt->getFullText() ) );
791 return wfMessage( 'autoredircomment', $rt->getFullText() )
792 ->rawParams( $truncatedtext )->inContentLanguage()->text();
796 // New page auto-summaries
797 if ( $flags & EDIT_NEW && $newContent->getSize() > 0 ) {
798 // If they're making a new article, give its text, truncated, in
799 // the summary.
801 $truncatedtext = $newContent->getTextForSummary(
802 200 - strlen( wfMessage( 'autosumm-new' )->inContentLanguage()->text() ) );
804 return wfMessage( 'autosumm-new' )->rawParams( $truncatedtext )
805 ->inContentLanguage()->text();
808 // Blanking auto-summaries
809 if ( !empty( $oldContent ) && $oldContent->getSize() > 0 && $newContent->getSize() == 0 ) {
810 return wfMessage( 'autosumm-blank' )->inContentLanguage()->text();
811 } elseif ( !empty( $oldContent )
812 && $oldContent->getSize() > 10 * $newContent->getSize()
813 && $newContent->getSize() < 500
815 // Removing more than 90% of the article
817 $truncatedtext = $newContent->getTextForSummary(
818 200 - strlen( wfMessage( 'autosumm-replace' )->inContentLanguage()->text() ) );
820 return wfMessage( 'autosumm-replace' )->rawParams( $truncatedtext )
821 ->inContentLanguage()->text();
824 // New blank article auto-summary
825 if ( $flags & EDIT_NEW && $newContent->isEmpty() ) {
826 return wfMessage( 'autosumm-newblank' )->inContentLanguage()->text();
829 // If we reach this point, there's no applicable auto-summary for our
830 // case, so our auto-summary is empty.
831 return '';
835 * Auto-generates a deletion reason
837 * @since 1.21
839 * @param Title $title The page's title
840 * @param bool &$hasHistory Whether the page has a history
842 * @return mixed String containing deletion reason or empty string, or
843 * boolean false if no revision occurred
845 * @todo &$hasHistory is extremely ugly, it's here because
846 * WikiPage::getAutoDeleteReason() and Article::generateReason()
847 * have it / want it.
849 public function getAutoDeleteReason( Title $title, &$hasHistory ) {
850 $dbw = wfGetDB( DB_MASTER );
852 // Get the last revision
853 $rev = Revision::newFromTitle( $title );
855 if ( is_null( $rev ) ) {
856 return false;
859 // Get the article's contents
860 $content = $rev->getContent();
861 $blank = false;
863 // If the page is blank, use the text from the previous revision,
864 // which can only be blank if there's a move/import/protect dummy
865 // revision involved
866 if ( !$content || $content->isEmpty() ) {
867 $prev = $rev->getPrevious();
869 if ( $prev ) {
870 $rev = $prev;
871 $content = $rev->getContent();
872 $blank = true;
876 $this->checkModelID( $rev->getContentModel() );
878 // Find out if there was only one contributor
879 // Only scan the last 20 revisions
880 $res = $dbw->select( 'revision', 'rev_user_text',
881 array(
882 'rev_page' => $title->getArticleID(),
883 $dbw->bitAnd( 'rev_deleted', Revision::DELETED_USER ) . ' = 0'
885 __METHOD__,
886 array( 'LIMIT' => 20 )
889 if ( $res === false ) {
890 // This page has no revisions, which is very weird
891 return false;
894 $hasHistory = ( $res->numRows() > 1 );
895 $row = $dbw->fetchObject( $res );
897 if ( $row ) { // $row is false if the only contributor is hidden
898 $onlyAuthor = $row->rev_user_text;
899 // Try to find a second contributor
900 foreach ( $res as $row ) {
901 if ( $row->rev_user_text != $onlyAuthor ) { // Bug 22999
902 $onlyAuthor = false;
903 break;
906 } else {
907 $onlyAuthor = false;
910 // Generate the summary with a '$1' placeholder
911 if ( $blank ) {
912 // The current revision is blank and the one before is also
913 // blank. It's just not our lucky day
914 $reason = wfMessage( 'exbeforeblank', '$1' )->inContentLanguage()->text();
915 } else {
916 if ( $onlyAuthor ) {
917 $reason = wfMessage(
918 'excontentauthor',
919 '$1',
920 $onlyAuthor
921 )->inContentLanguage()->text();
922 } else {
923 $reason = wfMessage( 'excontent', '$1' )->inContentLanguage()->text();
927 if ( $reason == '-' ) {
928 // Allow these UI messages to be blanked out cleanly
929 return '';
932 // Max content length = max comment length - length of the comment (excl. $1)
933 $text = $content ? $content->getTextForSummary( 255 - ( strlen( $reason ) - 2 ) ) : '';
935 // Now replace the '$1' placeholder
936 $reason = str_replace( '$1', $text, $reason );
938 return $reason;
942 * Get the Content object that needs to be saved in order to undo all revisions
943 * between $undo and $undoafter. Revisions must belong to the same page,
944 * must exist and must not be deleted.
946 * @since 1.21
948 * @param Revision $current The current text
949 * @param Revision $undo The revision to undo
950 * @param Revision $undoafter Must be an earlier revision than $undo
952 * @return mixed String on success, false on failure
954 public function getUndoContent( Revision $current, Revision $undo, Revision $undoafter ) {
955 $cur_content = $current->getContent();
957 if ( empty( $cur_content ) ) {
958 return false; // no page
961 $undo_content = $undo->getContent();
962 $undoafter_content = $undoafter->getContent();
964 if ( !$undo_content || !$undoafter_content ) {
965 return false; // no content to undo
968 $this->checkModelID( $cur_content->getModel() );
969 $this->checkModelID( $undo_content->getModel() );
970 $this->checkModelID( $undoafter_content->getModel() );
972 if ( $cur_content->equals( $undo_content ) ) {
973 // No use doing a merge if it's just a straight revert.
974 return $undoafter_content;
977 $undone_content = $this->merge3( $undo_content, $undoafter_content, $cur_content );
979 return $undone_content;
983 * Get parser options suitable for rendering and caching the article
985 * @param IContextSource|User|string $context One of the following:
986 * - IContextSource: Use the User and the Language of the provided
987 * context
988 * - User: Use the provided User object and $wgLang for the language,
989 * so use an IContextSource object if possible.
990 * - 'canonical': Canonical options (anonymous user with default
991 * preferences and content language).
993 * @throws MWException
994 * @return ParserOptions
996 public function makeParserOptions( $context ) {
997 global $wgContLang, $wgEnableParserLimitReporting;
999 if ( $context instanceof IContextSource ) {
1000 $options = ParserOptions::newFromContext( $context );
1001 } elseif ( $context instanceof User ) { // settings per user (even anons)
1002 $options = ParserOptions::newFromUser( $context );
1003 } elseif ( $context === 'canonical' ) { // canonical settings
1004 $options = ParserOptions::newFromUserAndLang( new User, $wgContLang );
1005 } else {
1006 throw new MWException( "Bad context for parser options: $context" );
1009 $options->enableLimitReport( $wgEnableParserLimitReporting ); // show inclusion/loop reports
1010 $options->setTidy( true ); // fix bad HTML
1012 return $options;
1016 * Returns true for content models that support caching using the
1017 * ParserCache mechanism. See WikiPage::isParserCacheUsed().
1019 * @since 1.21
1021 * @return bool Always false.
1023 public function isParserCacheSupported() {
1024 return false;
1028 * Returns true if this content model supports sections.
1029 * This default implementation returns false.
1031 * Content models that return true here should also implement
1032 * Content::getSection, Content::replaceSection, etc. to handle sections..
1034 * @return bool Always false.
1036 public function supportsSections() {
1037 return false;
1041 * Returns true if this content model supports redirects.
1042 * This default implementation returns false.
1044 * Content models that return true here should also implement
1045 * ContentHandler::makeRedirectContent to return a Content object.
1047 * @return bool Always false.
1049 public function supportsRedirects() {
1050 return false;
1054 * Logs a deprecation warning, visible if $wgDevelopmentWarnings, but only if
1055 * self::$enableDeprecationWarnings is set to true.
1057 * @param string $func The name of the deprecated function
1058 * @param string $version The version since the method is deprecated. Usually 1.21
1059 * for ContentHandler related stuff.
1060 * @param string|bool $component : Component to which the function belongs.
1061 * If false, it is assumed the function is in MediaWiki core.
1063 * @see ContentHandler::$enableDeprecationWarnings
1064 * @see wfDeprecated
1066 public static function deprecated( $func, $version, $component = false ) {
1067 if ( self::$enableDeprecationWarnings ) {
1068 wfDeprecated( $func, $version, $component, 3 );
1073 * Call a legacy hook that uses text instead of Content objects.
1074 * Will log a warning when a matching hook function is registered.
1075 * If the textual representation of the content is changed by the
1076 * hook function, a new Content object is constructed from the new
1077 * text.
1079 * @param string $event Event name
1080 * @param array $args Parameters passed to hook functions
1081 * @param bool $warn Whether to log a warning.
1082 * Default to self::$enableDeprecationWarnings.
1083 * May be set to false for testing.
1085 * @return bool True if no handler aborted the hook
1087 * @see ContentHandler::$enableDeprecationWarnings
1089 public static function runLegacyHooks( $event, $args = array(),
1090 $warn = null
1093 if ( $warn === null ) {
1094 $warn = self::$enableDeprecationWarnings;
1097 if ( !Hooks::isRegistered( $event ) ) {
1098 return true; // nothing to do here
1101 if ( $warn ) {
1102 // Log information about which handlers are registered for the legacy hook,
1103 // so we can find and fix them.
1105 $handlers = Hooks::getHandlers( $event );
1106 $handlerInfo = array();
1108 wfSuppressWarnings();
1110 foreach ( $handlers as $handler ) {
1111 if ( is_array( $handler ) ) {
1112 if ( is_object( $handler[0] ) ) {
1113 $info = get_class( $handler[0] );
1114 } else {
1115 $info = $handler[0];
1118 if ( isset( $handler[1] ) ) {
1119 $info .= '::' . $handler[1];
1121 } elseif ( is_object( $handler ) ) {
1122 $info = get_class( $handler[0] );
1123 $info .= '::on' . $event;
1124 } else {
1125 $info = $handler;
1128 $handlerInfo[] = $info;
1131 wfRestoreWarnings();
1133 wfWarn( "Using obsolete hook $event via ContentHandler::runLegacyHooks()! Handlers: " .
1134 implode( ', ', $handlerInfo ), 2 );
1137 // convert Content objects to text
1138 $contentObjects = array();
1139 $contentTexts = array();
1141 foreach ( $args as $k => $v ) {
1142 if ( $v instanceof Content ) {
1143 /* @var Content $v */
1145 $contentObjects[$k] = $v;
1147 $v = $v->serialize();
1148 $contentTexts[$k] = $v;
1149 $args[$k] = $v;
1153 // call the hook functions
1154 $ok = wfRunHooks( $event, $args );
1156 // see if the hook changed the text
1157 foreach ( $contentTexts as $k => $orig ) {
1158 /* @var Content $content */
1160 $modified = $args[$k];
1161 $content = $contentObjects[$k];
1163 if ( $modified !== $orig ) {
1164 // text was changed, create updated Content object
1165 $content = $content->getContentHandler()->unserializeContent( $modified );
1168 $args[$k] = $content;
1171 return $ok;