3 * Base classes for actions done on pages.
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23 * @defgroup Actions Action done on pages
27 * Actions are things which can be done to pages (edit, delete, rollback, etc). They
28 * are distinct from Special Pages because an action must apply to exactly one page.
30 * To add an action in an extension, create a subclass of Action, and add the key to
31 * $wgActions. There is also the deprecated UnknownAction hook
33 * Actions generally fall into two groups: the show-a-form-then-do-something-with-the-input
34 * format (protect, delete, move, etc), and the just-do-something format (watch, rollback,
35 * patrol, etc). The FormAction and FormlessAction classes represent these two groups.
37 abstract class Action implements MessageLocalizer {
40 * Page on which we're performing the action
42 * @var WikiPage|Article|ImagePage|CategoryPage|Page $page
47 * IContextSource if specified; otherwise we'll use the Context from the Page
49 * @var IContextSource $context
54 * The fields used to create the HTMLForm
61 * Get the Action subclass which should be used to handle this action, false if
62 * the action is disabled, or null if it's not recognised
63 * @param string $action
64 * @param array $overrides
65 * @return bool|null|string|callable|Action
67 final private static function getClass( $action, array $overrides ) {
69 $action = strtolower( $action );
71 if ( !isset( $wgActions[$action] ) ) {
75 if ( $wgActions[$action] === false ) {
77 } elseif ( $wgActions[$action] === true && isset( $overrides[$action] ) ) {
78 return $overrides[$action];
79 } elseif ( $wgActions[$action] === true ) {
80 return ucfirst( $action ) . 'Action';
82 return $wgActions[$action];
87 * Get an appropriate Action subclass for the given action
89 * @param string $action
91 * @param IContextSource|null $context
92 * @return Action|bool|null False if the action is disabled, null
93 * if it is not recognised
95 final public static function factory( $action, Page $page, IContextSource $context = null ) {
96 $classOrCallable = self::getClass( $action, $page->getActionOverrides() );
98 if ( is_string( $classOrCallable ) ) {
99 if ( !class_exists( $classOrCallable ) ) {
102 $obj = new $classOrCallable( $page, $context );
106 if ( is_callable( $classOrCallable ) ) {
107 return call_user_func_array( $classOrCallable, [ $page, $context ] );
110 return $classOrCallable;
114 * Get the action that will be executed, not necessarily the one passed
115 * passed through the "action" request parameter. Actions disabled in
116 * $wgActions will be replaced by "nosuchaction".
119 * @param IContextSource $context
120 * @return string Action name
122 final public static function getActionName( IContextSource $context ) {
125 $request = $context->getRequest();
126 $actionName = $request->getVal( 'action', 'view' );
128 // Check for disabled actions
129 if ( isset( $wgActions[$actionName] ) && $wgActions[$actionName] === false ) {
130 $actionName = 'nosuchaction';
133 // Workaround for bug #20966: inability of IE to provide an action dependent
134 // on which submit button is clicked.
135 if ( $actionName === 'historysubmit' ) {
136 if ( $request->getBool( 'revisiondelete' ) ) {
137 $actionName = 'revisiondelete';
138 } elseif ( $request->getBool( 'editchangetags' ) ) {
139 $actionName = 'editchangetags';
141 $actionName = 'view';
143 } elseif ( $actionName == 'editredlink' ) {
144 $actionName = 'edit';
147 // Trying to get a WikiPage for NS_SPECIAL etc. will result
148 // in WikiPage::factory throwing "Invalid or virtual namespace -1 given."
149 // For SpecialPages et al, default to action=view.
150 if ( !$context->canUseWikiPage() ) {
154 $action = self::factory( $actionName, $context->getWikiPage(), $context );
155 if ( $action instanceof Action ) {
156 return $action->getName();
159 return 'nosuchaction';
163 * Check if a given action is recognised, even if it's disabled
166 * @param string $name Name of an action
169 final public static function exists( $name ) {
170 return self::getClass( $name, [] ) !== null;
174 * Get the IContextSource in use here
176 * @return IContextSource
178 final public function getContext() {
179 if ( $this->context instanceof IContextSource ) {
180 return $this->context;
181 } elseif ( $this->page instanceof Article ) {
182 // NOTE: $this->page can be a WikiPage, which does not have a context.
183 wfDebug( __METHOD__ . ": no context known, falling back to Article's context.\n" );
184 return $this->page->getContext();
187 wfWarn( __METHOD__ . ': no context known, falling back to RequestContext::getMain().' );
188 return RequestContext::getMain();
192 * Get the WebRequest being used for this instance
197 final public function getRequest() {
198 return $this->getContext()->getRequest();
202 * Get the OutputPage being used for this instance
207 final public function getOutput() {
208 return $this->getContext()->getOutput();
212 * Shortcut to get the User being used for this instance
217 final public function getUser() {
218 return $this->getContext()->getUser();
222 * Shortcut to get the Skin being used for this instance
227 final public function getSkin() {
228 return $this->getContext()->getSkin();
232 * Shortcut to get the user Language being used for this instance
236 final public function getLanguage() {
237 return $this->getContext()->getLanguage();
241 * Shortcut to get the Title object from the page
246 final public function getTitle() {
247 return $this->page->getTitle();
251 * Get a Message object with context set
252 * Parameters are the same as wfMessage()
256 final public function msg( $key ) {
257 $params = func_get_args();
258 return call_user_func_array( [ $this->getContext(), 'msg' ], $params );
262 * Only public since 1.21
265 * @param IContextSource|null $context
267 public function __construct( Page $page, IContextSource $context = null ) {
268 if ( $context === null ) {
269 wfWarn( __METHOD__ . ' called without providing a Context object.' );
270 // NOTE: We could try to initialize $context using $page->getContext(),
271 // if $page is an Article. That however seems to not work seamlessly.
275 $this->context = $context;
279 * Return the name of the action this object responds to
282 * @return string Lowercase name
284 abstract public function getName();
287 * Get the permission required to perform this action. Often, but not always,
288 * the same as the action name
291 * @return string|null
293 public function getRestriction() {
298 * Checks if the given user (identified by an object) can perform this action. Can be
299 * overridden by sub-classes with more complicated permissions schemes. Failures here
300 * must throw subclasses of ErrorPageError
303 * @param User $user The user to check, or null to use the context user
304 * @throws UserBlockedError|ReadOnlyError|PermissionsError
306 protected function checkCanExecute( User $user ) {
307 $right = $this->getRestriction();
308 if ( $right !== null ) {
309 $errors = $this->getTitle()->getUserPermissionsErrors( $right, $user );
310 if ( count( $errors ) ) {
311 throw new PermissionsError( $right, $errors );
315 if ( $this->requiresUnblock() && $user->isBlocked() ) {
316 $block = $user->getBlock();
317 throw new UserBlockedError( $block );
320 // This should be checked at the end so that the user won't think the
321 // error is only temporary when he also don't have the rights to execute
323 if ( $this->requiresWrite() && wfReadOnly() ) {
324 throw new ReadOnlyError();
329 * Whether this action requires the wiki not to be locked
334 public function requiresWrite() {
339 * Whether this action can still be executed by a blocked user
344 public function requiresUnblock() {
349 * Set output headers for noindexing etc. This function will not be called through
350 * the execute() entry point, so only put UI-related stuff in here.
353 protected function setHeaders() {
354 $out = $this->getOutput();
355 $out->setRobotPolicy( "noindex,nofollow" );
356 $out->setPageTitle( $this->getPageTitle() );
357 $out->setSubtitle( $this->getDescription() );
358 $out->setArticleRelated( true );
362 * Returns the name that goes in the \<h1\> page title
366 protected function getPageTitle() {
367 return $this->getTitle()->getPrefixedText();
371 * Returns the description that goes below the \<h1\> tag
374 * @return string HTML
376 protected function getDescription() {
377 return $this->msg( strtolower( $this->getName() ) )->escaped();
381 * Adds help link with an icon via page indicators.
382 * Link target can be overridden by a local message containing a wikilink:
383 * the message key is: lowercase action name + '-helppage'.
384 * @param string $to Target MediaWiki.org page title or encoded URL.
385 * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
388 public function addHelpLink( $to, $overrideBaseUrl = false ) {
390 $msg = wfMessage( $wgContLang->lc(
391 self::getActionName( $this->getContext() )
394 if ( !$msg->isDisabled() ) {
395 $helpUrl = Skin::makeUrl( $msg->plain() );
396 $this->getOutput()->addHelpLink( $helpUrl, true );
398 $this->getOutput()->addHelpLink( $to, $overrideBaseUrl );
403 * The main action entry point. Do all output for display and send it to the context
404 * output. Do not use globals $wgOut, $wgRequest, etc, in implementations; use
405 * $this->getOutput(), etc.
408 * @throws ErrorPageError
410 abstract public function show();
413 * Call wfTransactionalTimeLimit() if this request was POSTed
416 protected function useTransactionalTimeLimit() {
417 if ( $this->getRequest()->wasPosted() ) {
418 wfTransactionalTimeLimit();
423 * Indicates whether this action may perform database writes
427 public function doesWrites() {