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 use MediaWiki\Auth\AuthManager;
  25 use MediaWiki\Linker\LinkRenderer;
  26 use MediaWiki\MediaWikiServices;
  27 use MediaWiki\Navigation\PrevNextNavigationRenderer;
  28
  29 /**
  30  * Parent class for all special pages.
  31  *
  32  * Includes some static functions for handling the special page list deprecated
  33  * in favor of SpecialPageFactory.
  34  *
  35  * @ingroup SpecialPage
  36  */
  37 class SpecialPage implements MessageLocalizer {
  38         // The canonical name of this special page
  39         // Also used for the default <h1> heading, @see getDescription()
  40         protected $mName;
  41
  42         // The local name of this special page
  43         private $mLocalName;
  44
  45         // Minimum user level required to access this page, or "" for anyone.
  46         // Also used to categorise the pages in Special:Specialpages
  47         protected $mRestriction;
  48
  49         // Listed in Special:Specialpages?
  50         private $mListed;
  51
  52         // Whether or not this special page is being included from an article
  53         protected $mIncluding;
  54
  55         // Whether the special page can be included in an article
  56         protected $mIncludable;
  57
  58         /**
  59          * Current request context
  60          * @var IContextSource
  61          */
  62         protected $mContext;
  63
  64         /**
  65          * @var \MediaWiki\Linker\LinkRenderer|null
  66          */
  67         private $linkRenderer;
  68
  69         /**
  70          * Get a localised Title object for a specified special page name
  71          * If you don't need a full Title object, consider using TitleValue through
  72          * getTitleValueFor() below.
  73          *
  74          * @since 1.9
  75          * @since 1.21 $fragment parameter added
  76          *
  77          * @param string $name
  78          * @param string|bool $subpage Subpage string, or false to not use a subpage
  79          * @param string $fragment The link fragment (after the "#")
  80          * @return Title
  81          * @throws MWException
  82          */
  83         public static function getTitleFor( $name, $subpage = false, $fragment = '' ) {
  84                 return Title::newFromTitleValue(
  85                         self::getTitleValueFor( $name, $subpage, $fragment )
  86                 );
  87         }
  88
  89         /**
  90          * Get a localised TitleValue object for a specified special page name
  91          *
  92          * @since 1.28
  93          * @param string $name
  94          * @param string|bool $subpage Subpage string, or false to not use a subpage
  95          * @param string $fragment The link fragment (after the "#")
  96          * @return TitleValue
  97          */
  98         public static function getTitleValueFor( $name, $subpage = false, $fragment = '' ) {
  99                 $name = MediaWikiServices::getInstance()->getSpecialPageFactory()->
 100                         getLocalNameFor( $name, $subpage );
 101
 102                 return new TitleValue( NS_SPECIAL, $name, $fragment );
 103         }
 104
 105         /**
 106          * Get a localised Title object for a page name with a possibly unvalidated subpage
 107          *
 108          * @param string $name
 109          * @param string|bool $subpage Subpage string, or false to not use a subpage
 110          * @return Title|null Title object or null if the page doesn't exist
 111          */
 112         public static function getSafeTitleFor( $name, $subpage = false ) {
 113                 $name = MediaWikiServices::getInstance()->getSpecialPageFactory()->
 114                         getLocalNameFor( $name, $subpage );
 115                 if ( $name ) {
 116                         return Title::makeTitleSafe( NS_SPECIAL, $name );
 117                 } else {
 118                         return null;
 119                 }
 120         }
 121
 122         /**
 123          * Default constructor for special pages
 124          * Derivative classes should call this from their constructor
 125          *     Note that if the user does not have the required level, an error message will
 126          *     be displayed by the default execute() method, without the global function ever
 127          *     being called.
 128          *
 129          *     If you override execute(), you can recover the default behavior with userCanExecute()
 130          *     and displayRestrictionError()
 131          *
 132          * @param string $name Name of the special page, as seen in links and URLs
 133          * @param string $restriction User right required, e.g. "block" or "delete"
 134          * @param bool $listed Whether the page is listed in Special:Specialpages
 135          * @param callable|bool $function Unused
 136          * @param string $file Unused
 137          * @param bool $includable Whether the page can be included in normal pages
 138          */
 139         public function __construct(
 140                 $name = '', $restriction = '', $listed = true,
 141                 $function = false, $file = '', $includable = false
 142         ) {
 143                 $this->mName = $name;
 144                 $this->mRestriction = $restriction;
 145                 $this->mListed = $listed;
 146                 $this->mIncludable = $includable;
 147         }
 148
 149         /**
 150          * Get the name of this Special Page.
 151          * @return string
 152          */
 153         function getName() {
 154                 return $this->mName;
 155         }
 156
 157         /**
 158          * Get the permission that a user must have to execute this page
 159          * @return string
 160          */
 161         function getRestriction() {
 162                 return $this->mRestriction;
 163         }
 164
 165         // @todo FIXME: Decide which syntax to use for this, and stick to it
 166
 167         /**
 168          * Whether this special page is listed in Special:SpecialPages
 169          * @since 1.3 (r3583)
 170          * @return bool
 171          */
 172         function isListed() {
 173                 return $this->mListed;
 174         }
 175
 176         /**
 177          * Set whether this page is listed in Special:Specialpages, at run-time
 178          * @since 1.3
 179          * @param bool $listed
 180          * @return bool
 181          */
 182         function setListed( $listed ) {
 183                 return wfSetVar( $this->mListed, $listed );
 184         }
 185
 186         /**
 187          * Get or set whether this special page is listed in Special:SpecialPages
 188          * @since 1.6
 189          * @param bool|null $x
 190          * @return bool
 191          */
 192         function listed( $x = null ) {
 193                 return wfSetVar( $this->mListed, $x );
 194         }
 195
 196         /**
 197          * Whether it's allowed to transclude the special page via {{Special:Foo/params}}
 198          * @return bool
 199          */
 200         public function isIncludable() {
 201                 return $this->mIncludable;
 202         }
 203
 204         /**
 205          * How long to cache page when it is being included.
 206          *
 207          * @note If cache time is not 0, then the current user becomes an anon
 208          *   if you want to do any per-user customizations, than this method
 209          *   must be overriden to return 0.
 210          * @since 1.26
 211          * @return int Time in seconds, 0 to disable caching altogether,
 212          *  false to use the parent page's cache settings
 213          */
 214         public function maxIncludeCacheTime() {
 215                 return $this->getConfig()->get( 'MiserMode' ) ? $this->getCacheTTL() : 0;
 216         }
 217
 218         /**
 219          * @return int Seconds that this page can be cached
 220          */
 221         protected function getCacheTTL() {
 222                 return 60 * 60;
 223         }
 224
 225         /**
 226          * Whether the special page is being evaluated via transclusion
 227          * @param bool|null $x
 228          * @return bool
 229          */
 230         function including( $x = null ) {
 231                 return wfSetVar( $this->mIncluding, $x );
 232         }
 233
 234         /**
 235          * Get the localised name of the special page
 236          * @return string
 237          */
 238         function getLocalName() {
 239                 if ( !isset( $this->mLocalName ) ) {
 240                         $this->mLocalName = MediaWikiServices::getInstance()->getSpecialPageFactory()->
 241                                 getLocalNameFor( $this->mName );
 242                 }
 243
 244                 return $this->mLocalName;
 245         }
 246
 247         /**
 248          * Is this page expensive (for some definition of expensive)?
 249          * Expensive pages are disabled or cached in miser mode.  Originally used
 250          * (and still overridden) by QueryPage and subclasses, moved here so that
 251          * Special:SpecialPages can safely call it for all special pages.
 252          *
 253          * @return bool
 254          */
 255         public function isExpensive() {
 256                 return false;
 257         }
 258
 259         /**
 260          * Is this page cached?
 261          * Expensive pages are cached or disabled in miser mode.
 262          * Used by QueryPage and subclasses, moved here so that
 263          * Special:SpecialPages can safely call it for all special pages.
 264          *
 265          * @return bool
 266          * @since 1.21
 267          */
 268         public function isCached() {
 269                 return false;
 270         }
 271
 272         /**
 273          * Can be overridden by subclasses with more complicated permissions
 274          * schemes.
 275          *
 276          * @return bool Should the page be displayed with the restricted-access
 277          *   pages?
 278          */
 279         public function isRestricted() {
 280                 // DWIM: If anons can do something, then it is not restricted
 281                 return $this->mRestriction != '' && !MediaWikiServices::getInstance()
 282                                 ->getPermissionManager()
 283                                 ->groupHasPermission( '*', $this->mRestriction );
 284         }
 285
 286         /**
 287          * Checks if the given user (identified by an object) can execute this
 288          * special page (as defined by $mRestriction).  Can be overridden by sub-
 289          * classes with more complicated permissions schemes.
 290          *
 291          * @param User $user The user to check
 292          * @return bool Does the user have permission to view the page?
 293          */
 294         public function userCanExecute( User $user ) {
 295                 return $user->isAllowed( $this->mRestriction );
 296         }
 297
 298         /**
 299          * Output an error message telling the user what access level they have to have
 300          * @throws PermissionsError
 301          */
 302         function displayRestrictionError() {
 303                 throw new PermissionsError( $this->mRestriction );
 304         }
 305
 306         /**
 307          * Checks if userCanExecute, and if not throws a PermissionsError
 308          *
 309          * @since 1.19
 310          * @return void
 311          * @throws PermissionsError
 312          */
 313         public function checkPermissions() {
 314                 if ( !$this->userCanExecute( $this->getUser() ) ) {
 315                         $this->displayRestrictionError();
 316                 }
 317         }
 318
 319         /**
 320          * If the wiki is currently in readonly mode, throws a ReadOnlyError
 321          *
 322          * @since 1.19
 323          * @return void
 324          * @throws ReadOnlyError
 325          */
 326         public function checkReadOnly() {
 327                 if ( wfReadOnly() ) {
 328                         throw new ReadOnlyError;
 329                 }
 330         }
 331
 332         /**
 333          * If the user is not logged in, throws UserNotLoggedIn error
 334          *
 335          * The user will be redirected to Special:Userlogin with the given message as an error on
 336          * the form.
 337          *
 338          * @since 1.23
 339          * @param string $reasonMsg [optional] Message key to be displayed on login page
 340          * @param string $titleMsg [optional] Passed on to UserNotLoggedIn constructor
 341          * @throws UserNotLoggedIn
 342          */
 343         public function requireLogin(
 344                 $reasonMsg = 'exception-nologin-text', $titleMsg = 'exception-nologin'
 345         ) {
 346                 if ( $this->getUser()->isAnon() ) {
 347                         throw new UserNotLoggedIn( $reasonMsg, $titleMsg );
 348                 }
 349         }
 350
 351         /**
 352          * Tells if the special page does something security-sensitive and needs extra defense against
 353          * a stolen account (e.g. a reauthentication). What exactly that will mean is decided by the
 354          * authentication framework.
 355          * @return bool|string False or the argument for AuthManager::securitySensitiveOperationStatus().
 356          *   Typically a special page needing elevated security would return its name here.
 357          */
 358         protected function getLoginSecurityLevel() {
 359                 return false;
 360         }
 361
 362         /**
 363          * Record preserved POST data after a reauthentication.
 364          *
 365          * This is called from checkLoginSecurityLevel() when returning from the
 366          * redirect for reauthentication, if the redirect had been served in
 367          * response to a POST request.
 368          *
 369          * The base SpecialPage implementation does nothing. If your subclass uses
 370          * getLoginSecurityLevel() or checkLoginSecurityLevel(), it should probably
 371          * implement this to do something with the data.
 372          *
 373          * @since 1.32
 374          * @param array $data
 375          */
 376         protected function setReauthPostData( array $data ) {
 377         }
 378
 379         /**
 380          * Verifies that the user meets the security level, possibly reauthenticating them in the process.
 381          *
 382          * This should be used when the page does something security-sensitive and needs extra defense
 383          * against a stolen account (e.g. a reauthentication). The authentication framework will make
 384          * an extra effort to make sure the user account is not compromised. What that exactly means
 385          * will depend on the system and user settings; e.g. the user might be required to log in again
 386          * unless their last login happened recently, or they might be given a second-factor challenge.
 387          *
 388          * Calling this method will result in one if these actions:
 389          * - return true: all good.
 390          * - return false and set a redirect: caller should abort; the redirect will take the user
 391          *   to the login page for reauthentication, and back.
 392          * - throw an exception if there is no way for the user to meet the requirements without using
 393          *   a different access method (e.g. this functionality is only available from a specific IP).
 394          *
 395          * Note that this does not in any way check that the user is authorized to use this special page
 396          * (use checkPermissions() for that).
 397          *
 398          * @param string|null $level A security level. Can be an arbitrary string, defaults to the page
 399          *   name.
 400          * @return bool False means a redirect to the reauthentication page has been set and processing
 401          *   of the special page should be aborted.
 402          * @throws ErrorPageError If the security level cannot be met, even with reauthentication.
 403          */
 404         protected function checkLoginSecurityLevel( $level = null ) {
 405                 $level = $level ?: $this->getName();
 406                 $key = 'SpecialPage:reauth:' . $this->getName();
 407                 $request = $this->getRequest();
 408
 409                 $securityStatus = AuthManager::singleton()->securitySensitiveOperationStatus( $level );
 410                 if ( $securityStatus === AuthManager::SEC_OK ) {
 411                         $uniqueId = $request->getVal( 'postUniqueId' );
 412                         if ( $uniqueId ) {
 413                                 $key .= ':' . $uniqueId;
 414                                 $session = $request->getSession();
 415                                 $data = $session->getSecret( $key );
 416                                 if ( $data ) {
 417                                         $session->remove( $key );
 418                                         $this->setReauthPostData( $data );
 419                                 }
 420                         }
 421                         return true;
 422                 } elseif ( $securityStatus === AuthManager::SEC_REAUTH ) {
 423                         $title = self::getTitleFor( 'Userlogin' );
 424                         $queryParams = $request->getQueryValues();
 425
 426                         if ( $request->wasPosted() ) {
 427                                 $data = array_diff_assoc( $request->getValues(), $request->getQueryValues() );
 428                                 if ( $data ) {
 429                                         // unique ID in case the same special page is open in multiple browser tabs
 430                                         $uniqueId = MWCryptRand::generateHex( 6 );
 431                                         $key .= ':' . $uniqueId;
 432                                         $queryParams['postUniqueId'] = $uniqueId;
 433                                         $session = $request->getSession();
 434                                         $session->persist(); // Just in case
 435                                         $session->setSecret( $key, $data );
 436                                 }
 437                         }
 438
 439                         $query = [
 440                                 'returnto' => $this->getFullTitle()->getPrefixedDBkey(),
 441                                 'returntoquery' => wfArrayToCgi( array_diff_key( $queryParams, [ 'title' => true ] ) ),
 442                                 'force' => $level,
 443                         ];
 444                         $url = $title->getFullURL( $query, false, PROTO_HTTPS );
 445
 446                         $this->getOutput()->redirect( $url );
 447                         return false;
 448                 }
 449
 450                 $titleMessage = wfMessage( 'specialpage-securitylevel-not-allowed-title' );
 451                 $errorMessage = wfMessage( 'specialpage-securitylevel-not-allowed' );
 452                 throw new ErrorPageError( $titleMessage, $errorMessage );
 453         }
 454
 455         /**
 456          * Return an array of subpages beginning with $search that this special page will accept.
 457          *
 458          * For example, if a page supports subpages "foo", "bar" and "baz" (as in Special:PageName/foo,
 459          * etc.):
 460          *
 461          *   - `prefixSearchSubpages( "ba" )` should return `[ "bar", "baz" ]`
 462          *   - `prefixSearchSubpages( "f" )` should return `[ "foo" ]`
 463          *   - `prefixSearchSubpages( "z" )` should return `[]`
 464          *   - `prefixSearchSubpages( "" )` should return `[ foo", "bar", "baz" ]`
 465          *
 466          * @param string $search Prefix to search for
 467          * @param int $limit Maximum number of results to return (usually 10)
 468          * @param int $offset Number of results to skip (usually 0)
 469          * @return string[] Matching subpages
 470          */
 471         public function prefixSearchSubpages( $search, $limit, $offset ) {
 472                 $subpages = $this->getSubpagesForPrefixSearch();
 473                 if ( !$subpages ) {
 474                         return [];
 475                 }
 476
 477                 return self::prefixSearchArray( $search, $limit, $subpages, $offset );
 478         }
 479
 480         /**
 481          * Return an array of subpages that this special page will accept for prefix
 482          * searches. If this method requires a query you might instead want to implement
 483          * prefixSearchSubpages() directly so you can support $limit and $offset. This
 484          * method is better for static-ish lists of things.
 485          *
 486          * @return string[] subpages to search from
 487          */
 488         protected function getSubpagesForPrefixSearch() {
 489                 return [];
 490         }
 491
 492         /**
 493          * Perform a regular substring search for prefixSearchSubpages
 494          * @param string $search Prefix to search for
 495          * @param int $limit Maximum number of results to return (usually 10)
 496          * @param int $offset Number of results to skip (usually 0)
 497          * @return string[] Matching subpages
 498          */
 499         protected function prefixSearchString( $search, $limit, $offset ) {
 500                 $title = Title::newFromText( $search );
 501                 if ( !$title || !$title->canExist() ) {
 502                         // No prefix suggestion in special and media namespace
 503                         return [];
 504                 }
 505
 506                 $searchEngine = MediaWikiServices::getInstance()->newSearchEngine();
 507                 $searchEngine->setLimitOffset( $limit, $offset );
 508                 $searchEngine->setNamespaces( [] );
 509                 $result = $searchEngine->defaultPrefixSearch( $search );
 510                 return array_map( function ( Title $t ) {
 511                         return $t->getPrefixedText();
 512                 }, $result );
 513         }
 514
 515         /**
 516          * Helper function for implementations of prefixSearchSubpages() that
 517          * filter the values in memory (as opposed to making a query).
 518          *
 519          * @since 1.24
 520          * @param string $search
 521          * @param int $limit
 522          * @param array $subpages
 523          * @param int $offset
 524          * @return string[]
 525          */
 526         protected static function prefixSearchArray( $search, $limit, array $subpages, $offset ) {
 527                 $escaped = preg_quote( $search, '/' );
 528                 return array_slice( preg_grep( "/^$escaped/i",
 529                         array_slice( $subpages, $offset ) ), 0, $limit );
 530         }
 531
 532         /**
 533          * Sets headers - this should be called from the execute() method of all derived classes!
 534          */
 535         function setHeaders() {
 536                 $out = $this->getOutput();
 537                 $out->setArticleRelated( false );
 538                 $out->setRobotPolicy( $this->getRobotPolicy() );
 539                 $out->setPageTitle( $this->getDescription() );
 540                 if ( $this->getConfig()->get( 'UseMediaWikiUIEverywhere' ) ) {
 541                         $out->addModuleStyles( [
 542                                 'mediawiki.ui.input',
 543                                 'mediawiki.ui.radio',
 544                                 'mediawiki.ui.checkbox',
 545                         ] );
 546                 }
 547         }
 548
 549         /**
 550          * Entry point.
 551          *
 552          * @since 1.20
 553          *
 554          * @param string|null $subPage
 555          */
 556         final public function run( $subPage ) {
 557                 /**
 558                  * Gets called before @see SpecialPage::execute.
 559                  * Return false to prevent calling execute() (since 1.27+).
 560                  *
 561                  * @since 1.20
 562                  *
 563                  * @param SpecialPage $this
 564                  * @param string|null $subPage
 565                  */
 566                 if ( !Hooks::run( 'SpecialPageBeforeExecute', [ $this, $subPage ] ) ) {
 567                         return;
 568                 }
 569
 570                 if ( $this->beforeExecute( $subPage ) === false ) {
 571                         return;
 572                 }
 573                 $this->execute( $subPage );
 574                 $this->afterExecute( $subPage );
 575
 576                 /**
 577                  * Gets called after @see SpecialPage::execute.
 578                  *
 579                  * @since 1.20
 580                  *
 581                  * @param SpecialPage $this
 582                  * @param string|null $subPage
 583                  */
 584                 Hooks::run( 'SpecialPageAfterExecute', [ $this, $subPage ] );
 585         }
 586
 587         /**
 588          * Gets called before @see SpecialPage::execute.
 589          * Return false to prevent calling execute() (since 1.27+).
 590          *
 591          * @since 1.20
 592          *
 593          * @param string|null $subPage
 594          * @return bool|void
 595          */
 596         protected function beforeExecute( $subPage ) {
 597                 // No-op
 598         }
 599
 600         /**
 601          * Gets called after @see SpecialPage::execute.
 602          *
 603          * @since 1.20
 604          *
 605          * @param string|null $subPage
 606          */
 607         protected function afterExecute( $subPage ) {
 608                 // No-op
 609         }
 610
 611         /**
 612          * Default execute method
 613          * Checks user permissions
 614          *
 615          * This must be overridden by subclasses; it will be made abstract in a future version
 616          *
 617          * @param string|null $subPage
 618          */
 619         public function execute( $subPage ) {
 620                 $this->setHeaders();
 621                 $this->checkPermissions();
 622                 $securityLevel = $this->getLoginSecurityLevel();
 623                 if ( $securityLevel !== false && !$this->checkLoginSecurityLevel( $securityLevel ) ) {
 624                         return;
 625                 }
 626                 $this->outputHeader();
 627         }
 628
 629         /**
 630          * Outputs a summary message on top of special pages
 631          * Per default the message key is the canonical name of the special page
 632          * May be overridden, i.e. by extensions to stick with the naming conventions
 633          * for message keys: 'extensionname-xxx'
 634          *
 635          * @param string $summaryMessageKey Message key of the summary
 636          */
 637         function outputHeader( $summaryMessageKey = '' ) {
 638                 if ( $summaryMessageKey == '' ) {
 639                         $msg = MediaWikiServices::getInstance()->getContentLanguage()->lc( $this->getName() ) .
 640                                 '-summary';
 641                 } else {
 642                         $msg = $summaryMessageKey;
 643                 }
 644                 if ( !$this->msg( $msg )->isDisabled() && !$this->including() ) {
 645                         $this->getOutput()->wrapWikiMsg(
 646                                 "<div class='mw-specialpage-summary'>\n$1\n</div>", $msg );
 647                 }
 648         }
 649
 650         /**
 651          * Returns the name that goes in the \<h1\> in the special page itself, and
 652          * also the name that will be listed in Special:Specialpages
 653          *
 654          * Derived classes can override this, but usually it is easier to keep the
 655          * default behavior.
 656          *
 657          * @return string
 658          */
 659         function getDescription() {
 660                 return $this->msg( strtolower( $this->mName ) )->text();
 661         }
 662
 663         /**
 664          * Get a self-referential title object
 665          *
 666          * @param string|bool $subpage
 667          * @return Title
 668          * @since 1.23
 669          */
 670         function getPageTitle( $subpage = false ) {
 671                 return self::getTitleFor( $this->mName, $subpage );
 672         }
 673
 674         /**
 675          * Sets the context this SpecialPage is executed in
 676          *
 677          * @param IContextSource $context
 678          * @since 1.18
 679          */
 680         public function setContext( $context ) {
 681                 $this->mContext = $context;
 682         }
 683
 684         /**
 685          * Gets the context this SpecialPage is executed in
 686          *
 687          * @return IContextSource|RequestContext
 688          * @since 1.18
 689          */
 690         public function getContext() {
 691                 if ( $this->mContext instanceof IContextSource ) {
 692                         return $this->mContext;
 693                 } else {
 694                         wfDebug( __METHOD__ . " called and \$mContext is null. " .
 695                                 "Return RequestContext::getMain(); for sanity\n" );
 696
 697                         return RequestContext::getMain();
 698                 }
 699         }
 700
 701         /**
 702          * Get the WebRequest being used for this instance
 703          *
 704          * @return WebRequest
 705          * @since 1.18
 706          */
 707         public function getRequest() {
 708                 return $this->getContext()->getRequest();
 709         }
 710
 711         /**
 712          * Get the OutputPage being used for this instance
 713          *
 714          * @return OutputPage
 715          * @since 1.18
 716          */
 717         public function getOutput() {
 718                 return $this->getContext()->getOutput();
 719         }
 720
 721         /**
 722          * Shortcut to get the User executing this instance
 723          *
 724          * @return User
 725          * @since 1.18
 726          */
 727         public function getUser() {
 728                 return $this->getContext()->getUser();
 729         }
 730
 731         /**
 732          * Shortcut to get the skin being used for this instance
 733          *
 734          * @return Skin
 735          * @since 1.18
 736          */
 737         public function getSkin() {
 738                 return $this->getContext()->getSkin();
 739         }
 740
 741         /**
 742          * Shortcut to get user's language
 743          *
 744          * @return Language
 745          * @since 1.19
 746          */
 747         public function getLanguage() {
 748                 return $this->getContext()->getLanguage();
 749         }
 750
 751         /**
 752          * Shortcut to get main config object
 753          * @return Config
 754          * @since 1.24
 755          */
 756         public function getConfig() {
 757                 return $this->getContext()->getConfig();
 758         }
 759
 760         /**
 761          * Return the full title, including $par
 762          *
 763          * @return Title
 764          * @since 1.18
 765          */
 766         public function getFullTitle() {
 767                 return $this->getContext()->getTitle();
 768         }
 769
 770         /**
 771          * Return the robot policy. Derived classes that override this can change
 772          * the robot policy set by setHeaders() from the default 'noindex,nofollow'.
 773          *
 774          * @return string
 775          * @since 1.23
 776          */
 777         protected function getRobotPolicy() {
 778                 return 'noindex,nofollow';
 779         }
 780
 781         /**
 782          * Wrapper around wfMessage that sets the current context.
 783          *
 784          * @since 1.16
 785          * @return Message
 786          * @see wfMessage
 787          */
 788         public function msg( $key /* $args */ ) {
 789                 $message = $this->getContext()->msg( ...func_get_args() );
 790                 // RequestContext passes context to wfMessage, and the language is set from
 791                 // the context, but setting the language for Message class removes the
 792                 // interface message status, which breaks for example usernameless gender
 793                 // invocations. Restore the flag when not including special page in content.
 794                 if ( $this->including() ) {
 795                         $message->setInterfaceMessageFlag( false );
 796                 }
 797
 798                 return $message;
 799         }
 800
 801         /**
 802          * Adds RSS/atom links
 803          *
 804          * @param array $params
 805          */
 806         protected function addFeedLinks( $params ) {
 807                 $feedTemplate = wfScript( 'api' );
 808
 809                 foreach ( $this->getConfig()->get( 'FeedClasses' ) as $format => $class ) {
 810                         $theseParams = $params + [ 'feedformat' => $format ];
 811                         $url = wfAppendQuery( $feedTemplate, $theseParams );
 812                         $this->getOutput()->addFeedLink( $format, $url );
 813                 }
 814         }
 815
 816         /**
 817          * Adds help link with an icon via page indicators.
 818          * Link target can be overridden by a local message containing a wikilink:
 819          * the message key is: lowercase special page name + '-helppage'.
 820          * @param string $to Target MediaWiki.org page title or encoded URL.
 821          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
 822          * @since 1.25
 823          */
 824         public function addHelpLink( $to, $overrideBaseUrl = false ) {
 825                 if ( $this->including() ) {
 826                         return;
 827                 }
 828
 829                 $msg = $this->msg(
 830                         MediaWikiServices::getInstance()->getContentLanguage()->lc( $this->getName() ) .
 831                         '-helppage' );
 832
 833                 if ( !$msg->isDisabled() ) {
 834                         $helpUrl = Skin::makeUrl( $msg->plain() );
 835                         $this->getOutput()->addHelpLink( $helpUrl, true );
 836                 } else {
 837                         $this->getOutput()->addHelpLink( $to, $overrideBaseUrl );
 838                 }
 839         }
 840
 841         /**
 842          * Get the group that the special page belongs in on Special:SpecialPage
 843          * Use this method, instead of getGroupName to allow customization
 844          * of the group name from the wiki side
 845          *
 846          * @return string Group of this special page
 847          * @since 1.21
 848          */
 849         public function getFinalGroupName() {
 850                 $name = $this->getName();
 851
 852                 // Allow overriding the group from the wiki side
 853                 $msg = $this->msg( 'specialpages-specialpagegroup-' . strtolower( $name ) )->inContentLanguage();
 854                 if ( !$msg->isBlank() ) {
 855                         $group = $msg->text();
 856                 } else {
 857                         // Than use the group from this object
 858                         $group = $this->getGroupName();
 859                 }
 860
 861                 return $group;
 862         }
 863
 864         /**
 865          * Indicates whether this special page may perform database writes
 866          *
 867          * @return bool
 868          * @since 1.27
 869          */
 870         public function doesWrites() {
 871                 return false;
 872         }
 873
 874         /**
 875          * Under which header this special page is listed in Special:SpecialPages
 876          * See messages 'specialpages-group-*' for valid names
 877          * This method defaults to group 'other'
 878          *
 879          * @return string
 880          * @since 1.21
 881          */
 882         protected function getGroupName() {
 883                 return 'other';
 884         }
 885
 886         /**
 887          * Call wfTransactionalTimeLimit() if this request was POSTed
 888          * @since 1.26
 889          */
 890         protected function useTransactionalTimeLimit() {
 891                 if ( $this->getRequest()->wasPosted() ) {
 892                         wfTransactionalTimeLimit();
 893                 }
 894         }
 895
 896         /**
 897          * @since 1.28
 898          * @return \MediaWiki\Linker\LinkRenderer
 899          */
 900         public function getLinkRenderer() {
 901                 if ( $this->linkRenderer ) {
 902                         return $this->linkRenderer;
 903                 } else {
 904                         return MediaWikiServices::getInstance()->getLinkRenderer();
 905                 }
 906         }
 907
 908         /**
 909          * @since 1.28
 910          * @param \MediaWiki\Linker\LinkRenderer $linkRenderer
 911          */
 912         public function setLinkRenderer( LinkRenderer $linkRenderer ) {
 913                 $this->linkRenderer = $linkRenderer;
 914         }
 915
 916         /**
 917          * Generate (prev x| next x) (20|50|100...) type links for paging
 918          *
 919          * @param int $offset
 920          * @param int $limit
 921          * @param array $query Optional URL query parameter string
 922          * @param bool $atend Optional param for specified if this is the last page
 923          * @param string|bool $subpage Optional param for specifying subpage
 924          * @return string
 925          */
 926         protected function buildPrevNextNavigation( $offset, $limit,
 927                                                                                          array $query = [], $atend = false, $subpage = false
 928         ) {
 929                 $title = $this->getPageTitle( $subpage );
 930                 $prevNext = new PrevNextNavigationRenderer( $this );
 931
 932                 return $prevNext->buildPrevNextNavigation( $title, $offset, $limit, $query,  $atend );
 933         }
 934 }