includes/specialpage/SpecialPage.php

   1 <?php
   2 /**
   3  * Parent class for all special pages.
   4  *
   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.
   9  *
  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.
  14  *
  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
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  */
  23
  24 /**
  25  * Parent class for all special pages.
  26  *
  27  * Includes some static functions for handling the special page list deprecated
  28  * in favor of SpecialPageFactory.
  29  *
  30  * @todo Turn this into a real ContextSource
  31  * @ingroup SpecialPage
  32  */
  33 class SpecialPage {
  34         // The canonical name of this special page
  35         // Also used for the default <h1> heading, @see getDescription()
  36         protected $mName;
  37
  38         // The local name of this special page
  39         private $mLocalName;
  40
  41         // Minimum user level required to access this page, or "" for anyone.
  42         // Also used to categorise the pages in Special:Specialpages
  43         private $mRestriction;
  44
  45         // Listed in Special:Specialpages?
  46         private $mListed;
  47
  48         // Function name called by the default execute()
  49         private $mFunction;
  50
  51         // File which needs to be included before the function above can be called
  52         private $mFile;
  53
  54         // Whether or not this special page is being included from an article
  55         protected $mIncluding;
  56
  57         // Whether the special page can be included in an article
  58         protected $mIncludable;
  59
  60         /**
  61          * Current request context
  62          * @var IContextSource
  63          */
  64         protected $mContext;
  65
  66         /**
  67          * Initialise the special page list
  68          * This must be called before accessing SpecialPage::$mList
  69          * @deprecated since 1.18
  70          */
  71         static function initList() {
  72                 wfDeprecated( __METHOD__, '1.18' );
  73                 // Noop
  74         }
  75
  76         /**
  77          * @deprecated since 1.18
  78          */
  79         static function initAliasList() {
  80                 wfDeprecated( __METHOD__, '1.18' );
  81                 // Noop
  82         }
  83
  84         /**
  85          * Given a special page alias, return the special page name.
  86          * Returns false if there is no such alias.
  87          *
  88          * @param $alias String
  89          * @return String or false
  90          * @deprecated since 1.18 call SpecialPageFactory method directly
  91          */
  92         static function resolveAlias( $alias ) {
  93                 wfDeprecated( __METHOD__, '1.18' );
  94                 list( $name, /*...*/ ) = SpecialPageFactory::resolveAlias( $alias );
  95                 return $name;
  96         }
  97
  98         /**
  99          * Given a special page name with a possible subpage, return an array
 100          * where the first element is the special page name and the second is the
 101          * subpage.
 102          *
 103          * @param $alias String
 104          * @return Array
 105          * @deprecated since 1.18 call SpecialPageFactory method directly
 106          */
 107         static function resolveAliasWithSubpage( $alias ) {
 108                 return SpecialPageFactory::resolveAlias( $alias );
 109         }
 110
 111         /**
 112          * Add a page to a certain display group for Special:SpecialPages
 113          *
 114          * @param $page Mixed: SpecialPage or string
 115          * @param $group String
 116          * @deprecated since 1.18 call SpecialPageFactory method directly
 117          */
 118         static function setGroup( $page, $group ) {
 119                 wfDeprecated( __METHOD__, '1.18' );
 120                 SpecialPageFactory::setGroup( $page, $group );
 121         }
 122
 123         /**
 124          * Get the group that the special page belongs in on Special:SpecialPage
 125          *
 126          * @param $page SpecialPage
 127          * @return string
 128          * @deprecated since 1.18 call SpecialPageFactory method directly
 129          */
 130         static function getGroup( &$page ) {
 131                 wfDeprecated( __METHOD__, '1.18' );
 132                 return SpecialPageFactory::getGroup( $page );
 133         }
 134
 135         /**
 136          * Remove a special page from the list
 137          * Formerly used to disable expensive or dangerous special pages. The
 138          * preferred method is now to add a SpecialPage_initList hook.
 139          * @deprecated since 1.18
 140          *
 141          * @param string $name the page to remove
 142          */
 143         static function removePage( $name ) {
 144                 wfDeprecated( __METHOD__, '1.18' );
 145                 unset( SpecialPageFactory::getList()->$name );
 146         }
 147
 148         /**
 149          * Check if a given name exist as a special page or as a special page alias
 150          *
 151          * @param string $name name of a special page
 152          * @return Boolean: true if a special page exists with this name
 153          * @deprecated since 1.18 call SpecialPageFactory method directly
 154          */
 155         static function exists( $name ) {
 156                 wfDeprecated( __METHOD__, '1.18' );
 157                 return SpecialPageFactory::exists( $name );
 158         }
 159
 160         /**
 161          * Find the object with a given name and return it (or NULL)
 162          *
 163          * @param $name String
 164          * @return SpecialPage object or null if the page doesn't exist
 165          * @deprecated since 1.18 call SpecialPageFactory method directly
 166          */
 167         static function getPage( $name ) {
 168                 wfDeprecated( __METHOD__, '1.18' );
 169                 return SpecialPageFactory::getPage( $name );
 170         }
 171
 172         /**
 173          * Get a special page with a given localised name, or NULL if there
 174          * is no such special page.
 175          *
 176          * @param $alias String
 177          * @return SpecialPage object or null if the page doesn't exist
 178          * @deprecated since 1.18 call SpecialPageFactory method directly
 179          */
 180         static function getPageByAlias( $alias ) {
 181                 wfDeprecated( __METHOD__, '1.18' );
 182                 return SpecialPageFactory::getPage( $alias );
 183         }
 184
 185         /**
 186          * Return categorised listable special pages which are available
 187          * for the current user, and everyone.
 188          *
 189          * @param $user User object to check permissions, $wgUser will be used
 190          *              if not provided
 191          * @return array Associative array mapping page's name to its SpecialPage object
 192          * @deprecated since 1.18 call SpecialPageFactory method directly
 193          */
 194         static function getUsablePages( User $user = null ) {
 195                 wfDeprecated( __METHOD__, '1.18' );
 196                 return SpecialPageFactory::getUsablePages( $user );
 197         }
 198
 199         /**
 200          * Return categorised listable special pages for all users
 201          *
 202          * @return array Associative array mapping page's name to its SpecialPage object
 203          * @deprecated since 1.18 call SpecialPageFactory method directly
 204          */
 205         static function getRegularPages() {
 206                 wfDeprecated( __METHOD__, '1.18' );
 207                 return SpecialPageFactory::getRegularPages();
 208         }
 209
 210         /**
 211          * Return categorised listable special pages which are available
 212          * for the current user, but not for everyone
 213          *
 214          * @return array Associative array mapping page's name to its SpecialPage object
 215          * @deprecated since 1.18 call SpecialPageFactory method directly
 216          */
 217         static function getRestrictedPages() {
 218                 wfDeprecated( __METHOD__, '1.18' );
 219                 return SpecialPageFactory::getRestrictedPages();
 220         }
 221
 222         /**
 223          * Execute a special page path.
 224          * The path may contain parameters, e.g. Special:Name/Params
 225          * Extracts the special page name and call the execute method, passing the parameters
 226          *
 227          * Returns a title object if the page is redirected, false if there was no such special
 228          * page, and true if it was successful.
 229          *
 230          * @param $title          Title object
 231          * @param $context        IContextSource
 232          * @param $including      Bool output is being captured for use in {{special:whatever}}
 233          * @return Bool
 234          * @deprecated since 1.18 call SpecialPageFactory method directly
 235          */
 236         public static function executePath( &$title, IContextSource &$context, $including = false ) {
 237                 wfDeprecated( __METHOD__, '1.18' );
 238                 return SpecialPageFactory::executePath( $title, $context, $including );
 239         }
 240
 241         /**
 242          * Get the local name for a specified canonical name
 243          *
 244          * @param $name String
 245          * @param $subpage Mixed: boolean false, or string
 246          *
 247          * @return String
 248          * @deprecated since 1.18 call SpecialPageFactory method directly
 249          */
 250         static function getLocalNameFor( $name, $subpage = false ) {
 251                 wfDeprecated( __METHOD__, '1.18' );
 252                 return SpecialPageFactory::getLocalNameFor( $name, $subpage );
 253         }
 254
 255         /**
 256          * Get a localised Title object for a specified special page name
 257          *
 258          * @param $name String
 259          * @param string|Bool $subpage subpage string, or false to not use a subpage
 260          * @param string $fragment the link fragment (after the "#")
 261          * @throws MWException
 262          * @return Title object
 263          */
 264         public static function getTitleFor( $name, $subpage = false, $fragment = '' ) {
 265                 $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
 266                 return Title::makeTitle( NS_SPECIAL, $name, $fragment );
 267         }
 268
 269         /**
 270          * Get a localised Title object for a page name with a possibly unvalidated subpage
 271          *
 272          * @param $name String
 273          * @param string|Bool $subpage subpage string, or false to not use a subpage
 274          * @return Title object or null if the page doesn't exist
 275          */
 276         public static function getSafeTitleFor( $name, $subpage = false ) {
 277                 $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
 278                 if ( $name ) {
 279                         return Title::makeTitleSafe( NS_SPECIAL, $name );
 280                 } else {
 281                         return null;
 282                 }
 283         }
 284
 285         /**
 286          * Get a title for a given alias
 287          *
 288          * @param $alias String
 289          * @return Title or null if there is no such alias
 290          * @deprecated since 1.18 call SpecialPageFactory method directly
 291          */
 292         static function getTitleForAlias( $alias ) {
 293                 wfDeprecated( __METHOD__, '1.18' );
 294                 return SpecialPageFactory::getTitleForAlias( $alias );
 295         }
 296
 297         /**
 298          * Default constructor for special pages
 299          * Derivative classes should call this from their constructor
 300          *     Note that if the user does not have the required level, an error message will
 301          *     be displayed by the default execute() method, without the global function ever
 302          *     being called.
 303          *
 304          *     If you override execute(), you can recover the default behavior with userCanExecute()
 305          *     and displayRestrictionError()
 306          *
 307          * @param string $name Name of the special page, as seen in links and URLs
 308          * @param string $restriction User right required, e.g. "block" or "delete"
 309          * @param bool $listed Whether the page is listed in Special:Specialpages
 310          * @param Callback|Bool $function Function called by execute(). By default
 311          * it is constructed from $name
 312          * @param string $file File which is included by execute(). It is also
 313          * constructed from $name by default
 314          * @param bool $includable Whether the page can be included in normal pages
 315          */
 316         public function __construct(
 317                 $name = '', $restriction = '', $listed = true,
 318                 $function = false, $file = 'default', $includable = false
 319         ) {
 320                 $this->init( $name, $restriction, $listed, $function, $file, $includable );
 321         }
 322
 323         /**
 324          * Do the real work for the constructor, mainly so __call() can intercept
 325          * calls to SpecialPage()
 326          * @param string $name Name of the special page, as seen in links and URLs
 327          * @param string $restriction User right required, e.g. "block" or "delete"
 328          * @param bool $listed Whether the page is listed in Special:Specialpages
 329          * @param Callback|Bool $function Function called by execute(). By default
 330          * it is constructed from $name
 331          * @param string $file File which is included by execute(). It is also
 332          * constructed from $name by default
 333          * @param bool $includable Whether the page can be included in normal pages
 334          */
 335         private function init( $name, $restriction, $listed, $function, $file, $includable ) {
 336                 $this->mName = $name;
 337                 $this->mRestriction = $restriction;
 338                 $this->mListed = $listed;
 339                 $this->mIncludable = $includable;
 340                 if ( !$function ) {
 341                         $this->mFunction = 'wfSpecial' . $name;
 342                 } else {
 343                         $this->mFunction = $function;
 344                 }
 345                 if ( $file === 'default' ) {
 346                         $this->mFile = __DIR__ . "/specials/Special$name.php";
 347                 } else {
 348                         $this->mFile = $file;
 349                 }
 350         }
 351
 352         /**
 353          * Use PHP's magic __call handler to get calls to the old PHP4 constructor
 354          * because PHP E_STRICT yells at you for having __construct() and SpecialPage()
 355          *
 356          * @param string $fName Name of called method
 357          * @param array $a Arguments to the method
 358          * @throws MWException
 359          * @deprecated since 1.17, call parent::__construct()
 360          */
 361         public function __call( $fName, $a ) {
 362                 // Deprecated messages now, remove in 1.19 or 1.20?
 363                 wfDeprecated( __METHOD__, '1.17' );
 364
 365                 // Sometimes $fName is SpecialPage, sometimes it's specialpage. <3 PHP
 366                 if ( strtolower( $fName ) == 'specialpage' ) {
 367                         $name = isset( $a[0] ) ? $a[0] : '';
 368                         $restriction = isset( $a[1] ) ? $a[1] : '';
 369                         $listed = isset( $a[2] ) ? $a[2] : true;
 370                         $function = isset( $a[3] ) ? $a[3] : false;
 371                         $file = isset( $a[4] ) ? $a[4] : 'default';
 372                         $includable = isset( $a[5] ) ? $a[5] : false;
 373                         $this->init( $name, $restriction, $listed, $function, $file, $includable );
 374                 } else {
 375                         $className = get_class( $this );
 376                         throw new MWException( "Call to undefined method $className::$fName" );
 377                 }
 378         }
 379
 380         /**
 381          * Get the name of this Special Page.
 382          * @return String
 383          */
 384         function getName() {
 385                 return $this->mName;
 386         }
 387
 388         /**
 389          * Get the permission that a user must have to execute this page
 390          * @return String
 391          */
 392         function getRestriction() {
 393                 return $this->mRestriction;
 394         }
 395
 396         /**
 397          * Get the file which will be included by SpecialPage::execute() if your extension is
 398          * still stuck in the past and hasn't overridden the execute() method.  No modern code
 399          * should want or need to know this.
 400          * @return String
 401          * @deprecated since 1.18
 402          */
 403         function getFile() {
 404                 wfDeprecated( __METHOD__, '1.18' );
 405                 return $this->mFile;
 406         }
 407
 408         // @todo FIXME: Decide which syntax to use for this, and stick to it
 409         /**
 410          * Whether this special page is listed in Special:SpecialPages
 411          * @since r3583 (v1.3)
 412          * @return Bool
 413          */
 414         function isListed() {
 415                 return $this->mListed;
 416         }
 417         /**
 418          * Set whether this page is listed in Special:Specialpages, at run-time
 419          * @since r3583 (v1.3)
 420          * @param $listed Bool
 421          * @return Bool
 422          */
 423         function setListed( $listed ) {
 424                 return wfSetVar( $this->mListed, $listed );
 425         }
 426         /**
 427          * Get or set whether this special page is listed in Special:SpecialPages
 428          * @since r11308 (v1.6)
 429          * @param $x Bool
 430          * @return Bool
 431          */
 432         function listed( $x = null ) {
 433                 return wfSetVar( $this->mListed, $x );
 434         }
 435
 436         /**
 437          * Whether it's allowed to transclude the special page via {{Special:Foo/params}}
 438          * @return Bool
 439          */
 440         public function isIncludable() {
 441                 return $this->mIncludable;
 442         }
 443
 444         /**
 445          * These mutators are very evil, as the relevant variables should not mutate.  So
 446          * don't use them.
 447          * @param $x Mixed
 448          * @return Mixed
 449          * @deprecated since 1.18
 450          */
 451         function name( $x = null ) {
 452                 wfDeprecated( __METHOD__, '1.18' );
 453                 return wfSetVar( $this->mName, $x );
 454         }
 455
 456         /**
 457          * These mutators are very evil, as the relevant variables should not mutate.  So
 458          * don't use them.
 459          * @param $x Mixed
 460          * @return Mixed
 461          * @deprecated since 1.18
 462          */
 463         function restriction( $x = null ) {
 464                 wfDeprecated( __METHOD__, '1.18' );
 465                 return wfSetVar( $this->mRestriction, $x );
 466         }
 467
 468         /**
 469          * These mutators are very evil, as the relevant variables should not mutate.  So
 470          * don't use them.
 471          * @param $x Mixed
 472          * @return Mixed
 473          * @deprecated since 1.18
 474          */
 475         function func( $x = null ) {
 476                 wfDeprecated( __METHOD__, '1.18' );
 477                 return wfSetVar( $this->mFunction, $x );
 478         }
 479
 480         /**
 481          * These mutators are very evil, as the relevant variables should not mutate.  So
 482          * don't use them.
 483          * @param $x Mixed
 484          * @return Mixed
 485          * @deprecated since 1.18
 486          */
 487         function file( $x = null ) {
 488                 wfDeprecated( __METHOD__, '1.18' );
 489                 return wfSetVar( $this->mFile, $x );
 490         }
 491
 492         /**
 493          * These mutators are very evil, as the relevant variables should not mutate.  So
 494          * don't use them.
 495          * @param $x Mixed
 496          * @return Mixed
 497          * @deprecated since 1.18
 498          */
 499         function includable( $x = null ) {
 500                 wfDeprecated( __METHOD__, '1.18' );
 501                 return wfSetVar( $this->mIncludable, $x );
 502         }
 503
 504         /**
 505          * Whether the special page is being evaluated via transclusion
 506          * @param $x Bool
 507          * @return Bool
 508          */
 509         function including( $x = null ) {
 510                 return wfSetVar( $this->mIncluding, $x );
 511         }
 512
 513         /**
 514          * Get the localised name of the special page
 515          */
 516         function getLocalName() {
 517                 if ( !isset( $this->mLocalName ) ) {
 518                         $this->mLocalName = SpecialPageFactory::getLocalNameFor( $this->mName );
 519                 }
 520                 return $this->mLocalName;
 521         }
 522
 523         /**
 524          * Is this page expensive (for some definition of expensive)?
 525          * Expensive pages are disabled or cached in miser mode.  Originally used
 526          * (and still overridden) by QueryPage and subclasses, moved here so that
 527          * Special:SpecialPages can safely call it for all special pages.
 528          *
 529          * @return Boolean
 530          */
 531         public function isExpensive() {
 532                 return false;
 533         }
 534
 535         /**
 536          * Is this page cached?
 537          * Expensive pages are cached or disabled in miser mode.
 538          * Used by QueryPage and subclasses, moved here so that
 539          * Special:SpecialPages can safely call it for all special pages.
 540          *
 541          * @return Boolean
 542          * @since 1.21
 543          */
 544         public function isCached() {
 545                 return false;
 546         }
 547
 548         /**
 549          * Can be overridden by subclasses with more complicated permissions
 550          * schemes.
 551          *
 552          * @return Boolean: should the page be displayed with the restricted-access
 553          *   pages?
 554          */
 555         public function isRestricted() {
 556                 // DWIM: If anons can do something, then it is not restricted
 557                 return $this->mRestriction != '' && !User::groupHasPermission( '*', $this->mRestriction );
 558         }
 559
 560         /**
 561          * Checks if the given user (identified by an object) can execute this
 562          * special page (as defined by $mRestriction).  Can be overridden by sub-
 563          * classes with more complicated permissions schemes.
 564          *
 565          * @param $user User: the user to check
 566          * @return Boolean: does the user have permission to view the page?
 567          */
 568         public function userCanExecute( User $user ) {
 569                 return $user->isAllowed( $this->mRestriction );
 570         }
 571
 572         /**
 573          * Output an error message telling the user what access level they have to have
 574          */
 575         function displayRestrictionError() {
 576                 throw new PermissionsError( $this->mRestriction );
 577         }
 578
 579         /**
 580          * Checks if userCanExecute, and if not throws a PermissionsError
 581          *
 582          * @since 1.19
 583          */
 584         public function checkPermissions() {
 585                 if ( !$this->userCanExecute( $this->getUser() ) ) {
 586                         $this->displayRestrictionError();
 587                 }
 588         }
 589
 590         /**
 591          * If the wiki is currently in readonly mode, throws a ReadOnlyError
 592          *
 593          * @since 1.19
 594          * @throws ReadOnlyError
 595          */
 596         public function checkReadOnly() {
 597                 if ( wfReadOnly() ) {
 598                         throw new ReadOnlyError;
 599                 }
 600         }
 601
 602         /**
 603          * If the user is not logged in, throws UserNotLoggedIn error.
 604          *
 605          * Default error message includes a link to Special:Userlogin with properly set 'returnto' query
 606          * parameter.
 607          *
 608          * @since 1.23
 609          * @param string|Message $reasonMsg [optional] Passed on to UserNotLoggedIn constructor. Strings
 610          *     will be used as message keys. If a string is given, the message will also receive a
 611          *     formatted login link (generated using the 'loginreqlink' message) as first parameter. If a
 612          *     Message is given, it will be passed on verbatim.
 613          * @param string|Message $titleMsg [optional] Passed on to UserNotLoggedIn constructor. Strings
 614          *     will be used as message keys.
 615          * @throws UserNotLoggedIn
 616          */
 617         public function requireLogin( $reasonMsg = null, $titleMsg = null ) {
 618                 if ( $this->getUser()->isAnon() ) {
 619                         // Use default messages if not given or explicit null passed
 620                         if ( !$reasonMsg ) {
 621                                 $reasonMsg = 'exception-nologin-text-manual';
 622                         }
 623                         if ( !$titleMsg ) {
 624                                 $titleMsg = 'exception-nologin';
 625                         }
 626
 627                         // Convert to Messages with current context
 628                         if ( is_string( $reasonMsg ) ) {
 629                                 $loginreqlink = Linker::linkKnown(
 630                                         SpecialPage::getTitleFor( 'Userlogin' ),
 631                                         $this->msg( 'loginreqlink' )->escaped(),
 632                                         array(),
 633                                         array( 'returnto' => $this->getPageTitle()->getPrefixedText() )
 634                                 );
 635                                 $reasonMsg = $this->msg( $reasonMsg )->rawParams( $loginreqlink );
 636                         }
 637                         if ( is_string( $titleMsg ) ) {
 638                                 $titleMsg = $this->msg( $titleMsg );
 639                         }
 640
 641                         throw new UserNotLoggedIn( $reasonMsg, $titleMsg );
 642                 }
 643         }
 644
 645         /**
 646          * Sets headers - this should be called from the execute() method of all derived classes!
 647          */
 648         function setHeaders() {
 649                 $out = $this->getOutput();
 650                 $out->setArticleRelated( false );
 651                 $out->setRobotPolicy( "noindex,nofollow" );
 652                 $out->setPageTitle( $this->getDescription() );
 653         }
 654
 655         /**
 656          * Entry point.
 657          *
 658          * @since 1.20
 659          *
 660          * @param $subPage string|null
 661          */
 662         final public function run( $subPage ) {
 663                 /**
 664                  * Gets called before @see SpecialPage::execute.
 665                  *
 666                  * @since 1.20
 667                  *
 668                  * @param $special SpecialPage
 669                  * @param $subPage string|null
 670                  */
 671                 wfRunHooks( 'SpecialPageBeforeExecute', array( $this, $subPage ) );
 672
 673                 $this->beforeExecute( $subPage );
 674                 $this->execute( $subPage );
 675                 $this->afterExecute( $subPage );
 676
 677                 /**
 678                  * Gets called after @see SpecialPage::execute.
 679                  *
 680                  * @since 1.20
 681                  *
 682                  * @param $special SpecialPage
 683                  * @param $subPage string|null
 684                  */
 685                 wfRunHooks( 'SpecialPageAfterExecute', array( $this, $subPage ) );
 686         }
 687
 688         /**
 689          * Gets called before @see SpecialPage::execute.
 690          *
 691          * @since 1.20
 692          *
 693          * @param $subPage string|null
 694          */
 695         protected function beforeExecute( $subPage ) {
 696                 // No-op
 697         }
 698
 699         /**
 700          * Gets called after @see SpecialPage::execute.
 701          *
 702          * @since 1.20
 703          *
 704          * @param $subPage string|null
 705          */
 706         protected function afterExecute( $subPage ) {
 707                 // No-op
 708         }
 709
 710         /**
 711          * Default execute method
 712          * Checks user permissions, calls the function given in mFunction
 713          *
 714          * This must be overridden by subclasses; it will be made abstract in a future version
 715          *
 716          * @param $subPage string|null
 717          */
 718         public function execute( $subPage ) {
 719                 $this->setHeaders();
 720                 $this->checkPermissions();
 721
 722                 $func = $this->mFunction;
 723                 // only load file if the function does not exist
 724                 if ( !is_callable( $func ) && $this->mFile ) {
 725                         require_once $this->mFile;
 726                 }
 727                 $this->outputHeader();
 728                 call_user_func( $func, $subPage, $this );
 729         }
 730
 731         /**
 732          * Outputs a summary message on top of special pages
 733          * Per default the message key is the canonical name of the special page
 734          * May be overridden, i.e. by extensions to stick with the naming conventions
 735          * for message keys: 'extensionname-xxx'
 736          *
 737          * @param string $summaryMessageKey message key of the summary
 738          */
 739         function outputHeader( $summaryMessageKey = '' ) {
 740                 global $wgContLang;
 741
 742                 if ( $summaryMessageKey == '' ) {
 743                         $msg = $wgContLang->lc( $this->getName() ) . '-summary';
 744                 } else {
 745                         $msg = $summaryMessageKey;
 746                 }
 747                 if ( !$this->msg( $msg )->isDisabled() && !$this->including() ) {
 748                         $this->getOutput()->wrapWikiMsg(
 749                                 "<div class='mw-specialpage-summary'>\n$1\n</div>", $msg );
 750                 }
 751
 752         }
 753
 754         /**
 755          * Returns the name that goes in the \<h1\> in the special page itself, and
 756          * also the name that will be listed in Special:Specialpages
 757          *
 758          * Derived classes can override this, but usually it is easier to keep the
 759          * default behavior.
 760          *
 761          * @return string
 762          */
 763         function getDescription() {
 764                 return $this->msg( strtolower( $this->mName ) )->text();
 765         }
 766
 767         /**
 768          * Get a self-referential title object
 769          *
 770          * @param $subpage String|Bool
 771          * @return Title object
 772          * @deprecated in 1.23, use SpecialPage::getPageTitle
 773          */
 774         function getTitle( $subpage = false ) {
 775                 wfDeprecated( __METHOD__, '1.23' );
 776                 return $this->getPageTitle( $subpage );
 777         }
 778
 779         /**
 780          * Get a self-referential title object
 781          *
 782          * @param $subpage String|Bool
 783          * @return Title object
 784          */
 785         function getPageTitle( $subpage = false ) {
 786                 return self::getTitleFor( $this->mName, $subpage );
 787         }
 788
 789         /**
 790          * Sets the context this SpecialPage is executed in
 791          *
 792          * @param $context IContextSource
 793          * @since 1.18
 794          */
 795         public function setContext( $context ) {
 796                 $this->mContext = $context;
 797         }
 798
 799         /**
 800          * Gets the context this SpecialPage is executed in
 801          *
 802          * @return IContextSource|RequestContext
 803          * @since 1.18
 804          */
 805         public function getContext() {
 806                 if ( $this->mContext instanceof IContextSource ) {
 807                         return $this->mContext;
 808                 } else {
 809                         wfDebug( __METHOD__ . " called and \$mContext is null. " .
 810                                 "Return RequestContext::getMain(); for sanity\n" );
 811                         return RequestContext::getMain();
 812                 }
 813         }
 814
 815         /**
 816          * Get the WebRequest being used for this instance
 817          *
 818          * @return WebRequest
 819          * @since 1.18
 820          */
 821         public function getRequest() {
 822                 return $this->getContext()->getRequest();
 823         }
 824
 825         /**
 826          * Get the OutputPage being used for this instance
 827          *
 828          * @return OutputPage
 829          * @since 1.18
 830          */
 831         public function getOutput() {
 832                 return $this->getContext()->getOutput();
 833         }
 834
 835         /**
 836          * Shortcut to get the User executing this instance
 837          *
 838          * @return User
 839          * @since 1.18
 840          */
 841         public function getUser() {
 842                 return $this->getContext()->getUser();
 843         }
 844
 845         /**
 846          * Shortcut to get the skin being used for this instance
 847          *
 848          * @return Skin
 849          * @since 1.18
 850          */
 851         public function getSkin() {
 852                 return $this->getContext()->getSkin();
 853         }
 854
 855         /**
 856          * Shortcut to get user's language
 857          *
 858          * @deprecated since 1.19 Use getLanguage instead
 859          * @return Language
 860          * @since 1.18
 861          */
 862         public function getLang() {
 863                 wfDeprecated( __METHOD__, '1.19' );
 864                 return $this->getLanguage();
 865         }
 866
 867         /**
 868          * Shortcut to get user's language
 869          *
 870          * @return Language
 871          * @since 1.19
 872          */
 873         public function getLanguage() {
 874                 return $this->getContext()->getLanguage();
 875         }
 876
 877         /**
 878          * Return the full title, including $par
 879          *
 880          * @return Title
 881          * @since 1.18
 882          */
 883         public function getFullTitle() {
 884                 return $this->getContext()->getTitle();
 885         }
 886
 887         /**
 888          * Wrapper around wfMessage that sets the current context.
 889          *
 890          * @return Message
 891          * @see wfMessage
 892          */
 893         public function msg( /* $args */ ) {
 894                 $message = call_user_func_array(
 895                         array( $this->getContext(), 'msg' ),
 896                         func_get_args()
 897                 );
 898                 // RequestContext passes context to wfMessage, and the language is set from
 899                 // the context, but setting the language for Message class removes the
 900                 // interface message status, which breaks for example usernameless gender
 901                 // invocations. Restore the flag when not including special page in content.
 902                 if ( $this->including() ) {
 903                         $message->setInterfaceMessageFlag( false );
 904                 }
 905                 return $message;
 906         }
 907
 908         /**
 909          * Adds RSS/atom links
 910          *
 911          * @param $params array
 912          */
 913         protected function addFeedLinks( $params ) {
 914                 global $wgFeedClasses;
 915
 916                 $feedTemplate = wfScript( 'api' );
 917
 918                 foreach ( $wgFeedClasses as $format => $class ) {
 919                         $theseParams = $params + array( 'feedformat' => $format );
 920                         $url = wfAppendQuery( $feedTemplate, $theseParams );
 921                         $this->getOutput()->addFeedLink( $format, $url );
 922                 }
 923         }
 924
 925         /**
 926          * Get the group that the special page belongs in on Special:SpecialPage
 927          * Use this method, instead of getGroupName to allow customization
 928          * of the group name from the wiki side
 929          *
 930          * @return string Group of this special page
 931          * @since 1.21
 932          */
 933         public function getFinalGroupName() {
 934                 global $wgSpecialPageGroups;
 935                 $name = $this->getName();
 936
 937                 // Allow overbidding the group from the wiki side
 938                 $msg = $this->msg( 'specialpages-specialpagegroup-' . strtolower( $name ) )->inContentLanguage();
 939                 if ( !$msg->isBlank() ) {
 940                         $group = $msg->text();
 941                 } else {
 942                         // Than use the group from this object
 943                         $group = $this->getGroupName();
 944
 945                         // Group '-' is used as default to have the chance to determine,
 946                         // if the special pages overrides this method,
 947                         // if not overridden, $wgSpecialPageGroups is checked for b/c
 948                         if ( $group === '-' && isset( $wgSpecialPageGroups[$name] ) ) {
 949                                 $group = $wgSpecialPageGroups[$name];
 950                         }
 951                 }
 952
 953                 // never give '-' back, change to 'other'
 954                 if ( $group === '-' ) {
 955                         $group = 'other';
 956                 }
 957
 958                 return $group;
 959         }
 960
 961         /**
 962          * Under which header this special page is listed in Special:SpecialPages
 963          * See messages 'specialpages-group-*' for valid names
 964          * This method defaults to group 'other'
 965          *
 966          * @return string
 967          * @since 1.21
 968          */
 969         protected function getGroupName() {
 970                 // '-' used here to determine, if this group is overridden or has a hardcoded 'other'
 971                 // Needed for b/c in getFinalGroupName
 972                 return '-';
 973         }
 974 }