includes/specialpage/SpecialPageFactory.php

   1 <?php
   2 /**
   3  * Factory for handling the special page list and generating SpecialPage objects.
   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  * @defgroup SpecialPage SpecialPage
  23  */
  24
  25 namespace MediaWiki\Special;
  26
  27 use Hooks;
  28 use IContextSource;
  29 use Language;
  30 use MediaWiki\Config\ServiceOptions;
  31 use MediaWiki\Linker\LinkRenderer;
  32 use Profiler;
  33 use RequestContext;
  34 use SpecialPage;
  35 use Title;
  36 use User;
  37
  38 /**
  39  * Factory for handling the special page list and generating SpecialPage objects.
  40  *
  41  * To add a special page in an extension, add to $wgSpecialPages either
  42  * an object instance or an array containing the name and constructor
  43  * parameters. The latter is preferred for performance reasons.
  44  *
  45  * The object instantiated must be either an instance of SpecialPage or a
  46  * sub-class thereof. It must have an execute() method, which sends the HTML
  47  * for the special page to $wgOut. The parent class has an execute() method
  48  * which distributes the call to the historical global functions. Additionally,
  49  * execute() also checks if the user has the necessary access privileges
  50  * and bails out if not.
  51  *
  52  * To add a core special page, use the similar static list in
  53  * SpecialPageFactory::$list. To remove a core static special page at runtime, use
  54  * a SpecialPage_initList hook.
  55  *
  56  * @note There are two classes called SpecialPageFactory.  You should use this first one, in
  57  * namespace MediaWiki\Special, which is a service.  \SpecialPageFactory is a deprecated collection
  58  * of static methods that forwards to the global service.
  59  *
  60  * @ingroup SpecialPage
  61  * @since 1.17
  62  */
  63 class SpecialPageFactory {
  64         /**
  65          * List of special page names to the subclass of SpecialPage which handles them.
  66          * @todo Make this a const when we drop HHVM support (T192166).  It can still be private in PHP
  67          * 7.1.
  68          */
  69         private static $coreList = [
  70                 // Maintenance Reports
  71                 'BrokenRedirects' => \BrokenRedirectsPage::class,
  72                 'Deadendpages' => \DeadendPagesPage::class,
  73                 'DoubleRedirects' => \DoubleRedirectsPage::class,
  74                 'Longpages' => \LongPagesPage::class,
  75                 'Ancientpages' => \AncientPagesPage::class,
  76                 'Lonelypages' => \LonelyPagesPage::class,
  77                 'Fewestrevisions' => \FewestrevisionsPage::class,
  78                 'Withoutinterwiki' => \WithoutInterwikiPage::class,
  79                 'Protectedpages' => \SpecialProtectedpages::class,
  80                 'Protectedtitles' => \SpecialProtectedtitles::class,
  81                 'Shortpages' => \ShortPagesPage::class,
  82                 'Uncategorizedcategories' => \UncategorizedCategoriesPage::class,
  83                 'Uncategorizedimages' => \UncategorizedImagesPage::class,
  84                 'Uncategorizedpages' => \UncategorizedPagesPage::class,
  85                 'Uncategorizedtemplates' => \UncategorizedTemplatesPage::class,
  86                 'Unusedcategories' => \UnusedCategoriesPage::class,
  87                 'Unusedimages' => \UnusedimagesPage::class,
  88                 'Unusedtemplates' => \UnusedtemplatesPage::class,
  89                 'Unwatchedpages' => \UnwatchedpagesPage::class,
  90                 'Wantedcategories' => \WantedCategoriesPage::class,
  91                 'Wantedfiles' => \WantedFilesPage::class,
  92                 'Wantedpages' => \WantedPagesPage::class,
  93                 'Wantedtemplates' => \WantedTemplatesPage::class,
  94
  95                 // List of pages
  96                 'Allpages' => \SpecialAllPages::class,
  97                 'Prefixindex' => \SpecialPrefixindex::class,
  98                 'Categories' => \SpecialCategories::class,
  99                 'Listredirects' => \ListredirectsPage::class,
 100                 'PagesWithProp' => \SpecialPagesWithProp::class,
 101                 'TrackingCategories' => \SpecialTrackingCategories::class,
 102
 103                 // Authentication
 104                 'Userlogin' => \SpecialUserLogin::class,
 105                 'Userlogout' => \SpecialUserLogout::class,
 106                 'CreateAccount' => \SpecialCreateAccount::class,
 107                 'LinkAccounts' => \SpecialLinkAccounts::class,
 108                 'UnlinkAccounts' => \SpecialUnlinkAccounts::class,
 109                 'ChangeCredentials' => \SpecialChangeCredentials::class,
 110                 'RemoveCredentials' => \SpecialRemoveCredentials::class,
 111
 112                 // Users and rights
 113                 'Activeusers' => \SpecialActiveUsers::class,
 114                 'Block' => \SpecialBlock::class,
 115                 'Unblock' => \SpecialUnblock::class,
 116                 'BlockList' => \SpecialBlockList::class,
 117                 'AutoblockList' => \SpecialAutoblockList::class,
 118                 'ChangePassword' => \SpecialChangePassword::class,
 119                 'BotPasswords' => \SpecialBotPasswords::class,
 120                 'PasswordReset' => \SpecialPasswordReset::class,
 121                 'DeletedContributions' => \DeletedContributionsPage::class,
 122                 'Preferences' => \SpecialPreferences::class,
 123                 'ResetTokens' => \SpecialResetTokens::class,
 124                 'Contributions' => \SpecialContributions::class,
 125                 'Listgrouprights' => \SpecialListGroupRights::class,
 126                 'Listgrants' => \SpecialListGrants::class,
 127                 'Listusers' => \SpecialListUsers::class,
 128                 'Listadmins' => \SpecialListAdmins::class,
 129                 'Listbots' => \SpecialListBots::class,
 130                 'Userrights' => \UserrightsPage::class,
 131                 'EditWatchlist' => \SpecialEditWatchlist::class,
 132                 'PasswordPolicies' => \SpecialPasswordPolicies::class,
 133
 134                 // Recent changes and logs
 135                 'Newimages' => \SpecialNewFiles::class,
 136                 'Log' => \SpecialLog::class,
 137                 'Watchlist' => \SpecialWatchlist::class,
 138                 'Newpages' => \SpecialNewpages::class,
 139                 'Recentchanges' => \SpecialRecentChanges::class,
 140                 'Recentchangeslinked' => \SpecialRecentChangesLinked::class,
 141                 'Tags' => \SpecialTags::class,
 142
 143                 // Media reports and uploads
 144                 'Listfiles' => \SpecialListFiles::class,
 145                 'Filepath' => \SpecialFilepath::class,
 146                 'MediaStatistics' => \MediaStatisticsPage::class,
 147                 'MIMEsearch' => \MIMEsearchPage::class,
 148                 'FileDuplicateSearch' => \FileDuplicateSearchPage::class,
 149                 'Upload' => \SpecialUpload::class,
 150                 'UploadStash' => \SpecialUploadStash::class,
 151                 'ListDuplicatedFiles' => \ListDuplicatedFilesPage::class,
 152
 153                 // Data and tools
 154                 'ApiSandbox' => \SpecialApiSandbox::class,
 155                 'Statistics' => \SpecialStatistics::class,
 156                 'Allmessages' => \SpecialAllMessages::class,
 157                 'Version' => \SpecialVersion::class,
 158                 'Lockdb' => \SpecialLockdb::class,
 159                 'Unlockdb' => \SpecialUnlockdb::class,
 160
 161                 // Redirecting special pages
 162                 'LinkSearch' => \LinkSearchPage::class,
 163                 'Randompage' => \RandomPage::class,
 164                 'RandomInCategory' => \SpecialRandomInCategory::class,
 165                 'Randomredirect' => \SpecialRandomredirect::class,
 166                 'Randomrootpage' => \SpecialRandomrootpage::class,
 167                 'GoToInterwiki' => \SpecialGoToInterwiki::class,
 168
 169                 // High use pages
 170                 'Mostlinkedcategories' => \MostlinkedCategoriesPage::class,
 171                 'Mostimages' => \MostimagesPage::class,
 172                 'Mostinterwikis' => \MostinterwikisPage::class,
 173                 'Mostlinked' => \MostlinkedPage::class,
 174                 'Mostlinkedtemplates' => \MostlinkedTemplatesPage::class,
 175                 'Mostcategories' => \MostcategoriesPage::class,
 176                 'Mostrevisions' => \MostrevisionsPage::class,
 177
 178                 // Page tools
 179                 'ComparePages' => \SpecialComparePages::class,
 180                 'Export' => \SpecialExport::class,
 181                 'Import' => \SpecialImport::class,
 182                 'Undelete' => \SpecialUndelete::class,
 183                 'Whatlinkshere' => \SpecialWhatLinksHere::class,
 184                 'MergeHistory' => \SpecialMergeHistory::class,
 185                 'ExpandTemplates' => \SpecialExpandTemplates::class,
 186
 187                 // Other
 188                 'Booksources' => \SpecialBookSources::class,
 189
 190                 // Unlisted / redirects
 191                 'ApiHelp' => \SpecialApiHelp::class,
 192                 'Blankpage' => \SpecialBlankpage::class,
 193                 'Diff' => \SpecialDiff::class,
 194                 'EditTags' => \SpecialEditTags::class,
 195                 'Emailuser' => \SpecialEmailUser::class,
 196                 'Movepage' => \MovePageForm::class,
 197                 'Mycontributions' => \SpecialMycontributions::class,
 198                 'MyLanguage' => \SpecialMyLanguage::class,
 199                 'Mypage' => \SpecialMypage::class,
 200                 'Mytalk' => \SpecialMytalk::class,
 201                 'Myuploads' => \SpecialMyuploads::class,
 202                 'AllMyUploads' => \SpecialAllMyUploads::class,
 203                 'NewSection' => \SpecialNewSection::class,
 204                 'PermanentLink' => \SpecialPermanentLink::class,
 205                 'Redirect' => \SpecialRedirect::class,
 206                 'Revisiondelete' => \SpecialRevisionDelete::class,
 207                 'RunJobs' => \SpecialRunJobs::class,
 208                 'Specialpages' => \SpecialSpecialpages::class,
 209                 'PageData' => \SpecialPageData::class,
 210         ];
 211
 212         /** @var array Special page name => class name */
 213         private $list;
 214
 215         /** @var array */
 216         private $aliases;
 217
 218         /** @var ServiceOptions */
 219         private $options;
 220
 221         /** @var Language */
 222         private $contLang;
 223
 224         /**
 225          * TODO Make this a const when HHVM support is dropped (T192166)
 226          *
 227          * @var array
 228          * @since 1.33
 229          */
 230         public static $constructorOptions = [
 231                 'ContentHandlerUseDB',
 232                 'DisableInternalSearch',
 233                 'EmailAuthentication',
 234                 'EnableEmail',
 235                 'EnableJavaScriptTest',
 236                 'EnableSpecialMute',
 237                 'PageLanguageUseDB',
 238                 'SpecialPages',
 239         ];
 240
 241         /**
 242          * @param ServiceOptions $options
 243          * @param Language $contLang
 244          */
 245         public function __construct( ServiceOptions $options, Language $contLang ) {
 246                 $options->assertRequiredOptions( self::$constructorOptions );
 247                 $this->options = $options;
 248                 $this->contLang = $contLang;
 249         }
 250
 251         /**
 252          * Returns a list of canonical special page names.
 253          * May be used to iterate over all registered special pages.
 254          *
 255          * @return string[]
 256          */
 257         public function getNames() : array {
 258                 return array_keys( $this->getPageList() );
 259         }
 260
 261         /**
 262          * Get the special page list as an array
 263          *
 264          * @return array
 265          */
 266         private function getPageList() : array {
 267                 if ( !is_array( $this->list ) ) {
 268                         $this->list = self::$coreList;
 269
 270                         if ( !$this->options->get( 'DisableInternalSearch' ) ) {
 271                                 $this->list['Search'] = \SpecialSearch::class;
 272                         }
 273
 274                         if ( $this->options->get( 'EmailAuthentication' ) ) {
 275                                 $this->list['Confirmemail'] = \EmailConfirmation::class;
 276                                 $this->list['Invalidateemail'] = \EmailInvalidation::class;
 277                         }
 278
 279                         if ( $this->options->get( 'EnableEmail' ) ) {
 280                                 $this->list['ChangeEmail'] = \SpecialChangeEmail::class;
 281                         }
 282
 283                         if ( $this->options->get( 'EnableJavaScriptTest' ) ) {
 284                                 $this->list['JavaScriptTest'] = \SpecialJavaScriptTest::class;
 285                         }
 286
 287                         if ( $this->options->get( 'EnableSpecialMute' ) ) {
 288                                 $this->list['Mute'] = \SpecialMute::class;
 289                         }
 290
 291                         if ( $this->options->get( 'PageLanguageUseDB' ) ) {
 292                                 $this->list['PageLanguage'] = \SpecialPageLanguage::class;
 293                         }
 294
 295                         if ( $this->options->get( 'ContentHandlerUseDB' ) ) {
 296                                 $this->list['ChangeContentModel'] = \SpecialChangeContentModel::class;
 297                         }
 298
 299                         // Add extension special pages
 300                         $this->list = array_merge( $this->list, $this->options->get( 'SpecialPages' ) );
 301
 302                         // This hook can be used to disable unwanted core special pages
 303                         // or conditionally register special pages.
 304                         Hooks::run( 'SpecialPage_initList', [ &$this->list ] );
 305
 306                 }
 307
 308                 return $this->list;
 309         }
 310
 311         /**
 312          * Initialise and return the list of special page aliases. Returns an array where
 313          * the key is an alias, and the value is the canonical name of the special page.
 314          * All registered special pages are guaranteed to map to themselves.
 315          * @return array
 316          */
 317         private function getAliasList() : array {
 318                 if ( is_null( $this->aliases ) ) {
 319                         $aliases = $this->contLang->getSpecialPageAliases();
 320                         $pageList = $this->getPageList();
 321
 322                         $this->aliases = [];
 323                         $keepAlias = [];
 324
 325                         // Force every canonical name to be an alias for itself.
 326                         foreach ( $pageList as $name => $stuff ) {
 327                                 $caseFoldedAlias = $this->contLang->caseFold( $name );
 328                                 $this->aliases[$caseFoldedAlias] = $name;
 329                                 $keepAlias[$caseFoldedAlias] = 'canonical';
 330                         }
 331
 332                         // Check for $aliases being an array since Language::getSpecialPageAliases can return null
 333                         if ( is_array( $aliases ) ) {
 334                                 foreach ( $aliases as $realName => $aliasList ) {
 335                                         $aliasList = array_values( $aliasList );
 336                                         foreach ( $aliasList as $i => $alias ) {
 337                                                 $caseFoldedAlias = $this->contLang->caseFold( $alias );
 338
 339                                                 if ( isset( $this->aliases[$caseFoldedAlias] ) &&
 340                                                         $realName === $this->aliases[$caseFoldedAlias]
 341                                                 ) {
 342                                                         // Ignore same-realName conflicts
 343                                                         continue;
 344                                                 }
 345
 346                                                 if ( !isset( $keepAlias[$caseFoldedAlias] ) ) {
 347                                                         $this->aliases[$caseFoldedAlias] = $realName;
 348                                                         if ( !$i ) {
 349                                                                 $keepAlias[$caseFoldedAlias] = 'first';
 350                                                         }
 351                                                 } elseif ( !$i ) {
 352                                                         wfWarn( "First alias '$alias' for $realName conflicts with " .
 353                                                                 "{$keepAlias[$caseFoldedAlias]} alias for " .
 354                                                                 $this->aliases[$caseFoldedAlias]
 355                                                         );
 356                                                 }
 357                                         }
 358                                 }
 359                         }
 360                 }
 361
 362                 return $this->aliases;
 363         }
 364
 365         /**
 366          * Given a special page name with a possible subpage, return an array
 367          * where the first element is the special page name and the second is the
 368          * subpage.
 369          *
 370          * @param string $alias
 371          * @return array [ String, String|null ], or [ null, null ] if the page is invalid
 372          */
 373         public function resolveAlias( $alias ) {
 374                 $bits = explode( '/', $alias, 2 );
 375
 376                 $caseFoldedAlias = $this->contLang->caseFold( $bits[0] );
 377                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 378                 $aliases = $this->getAliasList();
 379                 if ( !isset( $aliases[$caseFoldedAlias] ) ) {
 380                         return [ null, null ];
 381                 }
 382                 $name = $aliases[$caseFoldedAlias];
 383                 $par = $bits[1] ?? null; // T4087
 384
 385                 return [ $name, $par ];
 386         }
 387
 388         /**
 389          * Check if a given name exist as a special page or as a special page alias
 390          *
 391          * @param string $name Name of a special page
 392          * @return bool True if a special page exists with this name
 393          */
 394         public function exists( $name ) {
 395                 list( $title, /*...*/ ) = $this->resolveAlias( $name );
 396
 397                 $specialPageList = $this->getPageList();
 398                 return isset( $specialPageList[$title] );
 399         }
 400
 401         /**
 402          * Find the object with a given name and return it (or NULL)
 403          *
 404          * @param string $name Special page name, may be localised and/or an alias
 405          * @return SpecialPage|null SpecialPage object or null if the page doesn't exist
 406          */
 407         public function getPage( $name ) {
 408                 list( $realName, /*...*/ ) = $this->resolveAlias( $name );
 409
 410                 $specialPageList = $this->getPageList();
 411
 412                 if ( isset( $specialPageList[$realName] ) ) {
 413                         $rec = $specialPageList[$realName];
 414
 415                         if ( is_callable( $rec ) ) {
 416                                 // Use callback to instantiate the special page
 417                                 $page = $rec();
 418                         } elseif ( is_string( $rec ) ) {
 419                                 $className = $rec;
 420                                 $page = new $className;
 421                         } elseif ( $rec instanceof SpecialPage ) {
 422                                 $page = $rec; // XXX: we should deep clone here
 423                         } else {
 424                                 $page = null;
 425                         }
 426
 427                         if ( $page instanceof SpecialPage ) {
 428                                 return $page;
 429                         }
 430
 431                         // It's not a classname, nor a callback, nor a legacy constructor array,
 432                         // nor a special page object. Give up.
 433                         wfLogWarning( "Cannot instantiate special page $realName: bad spec!" );
 434                 }
 435
 436                 return null;
 437         }
 438
 439         /**
 440          * Return categorised listable special pages which are available
 441          * for the current user, and everyone.
 442          *
 443          * @param User $user User object to check permissions
 444          *  provided
 445          * @return array ( string => Specialpage )
 446          */
 447         public function getUsablePages( User $user ) : array {
 448                 $pages = [];
 449                 foreach ( $this->getPageList() as $name => $rec ) {
 450                         $page = $this->getPage( $name );
 451                         if ( $page ) { // not null
 452                                 $page->setContext( RequestContext::getMain() );
 453                                 if ( $page->isListed()
 454                                         && ( !$page->isRestricted() || $page->userCanExecute( $user ) )
 455                                 ) {
 456                                         $pages[$name] = $page;
 457                                 }
 458                         }
 459                 }
 460
 461                 return $pages;
 462         }
 463
 464         /**
 465          * Return categorised listable special pages for all users
 466          *
 467          * @return array ( string => Specialpage )
 468          */
 469         public function getRegularPages() : array {
 470                 $pages = [];
 471                 foreach ( $this->getPageList() as $name => $rec ) {
 472                         $page = $this->getPage( $name );
 473                         if ( $page && $page->isListed() && !$page->isRestricted() ) {
 474                                 $pages[$name] = $page;
 475                         }
 476                 }
 477
 478                 return $pages;
 479         }
 480
 481         /**
 482          * Return categorised listable special pages which are available
 483          * for the current user, but not for everyone
 484          *
 485          * @param User $user User object to use
 486          * @return array ( string => Specialpage )
 487          */
 488         public function getRestrictedPages( User $user ) : array {
 489                 $pages = [];
 490                 foreach ( $this->getPageList() as $name => $rec ) {
 491                         $page = $this->getPage( $name );
 492                         if ( $page
 493                                 && $page->isListed()
 494                                 && $page->isRestricted()
 495                                 && $page->userCanExecute( $user )
 496                         ) {
 497                                 $pages[$name] = $page;
 498                         }
 499                 }
 500
 501                 return $pages;
 502         }
 503
 504         /**
 505          * Execute a special page path.
 506          * The path may contain parameters, e.g. Special:Name/Params
 507          * Extracts the special page name and call the execute method, passing the parameters
 508          *
 509          * Returns a title object if the page is redirected, false if there was no such special
 510          * page, and true if it was successful.
 511          *
 512          * @param Title &$title
 513          * @param IContextSource &$context
 514          * @param bool $including Bool output is being captured for use in {{special:whatever}}
 515          * @param LinkRenderer|null $linkRenderer (since 1.28)
 516          *
 517          * @return bool|Title
 518          */
 519         public function executePath( Title &$title, IContextSource &$context, $including = false,
 520                 LinkRenderer $linkRenderer = null
 521         ) {
 522                 // @todo FIXME: Redirects broken due to this call
 523                 $bits = explode( '/', $title->getDBkey(), 2 );
 524                 $name = $bits[0];
 525                 $par = $bits[1] ?? null; // T4087
 526
 527                 $page = $this->getPage( $name );
 528                 if ( !$page ) {
 529                         $context->getOutput()->setArticleRelated( false );
 530                         $context->getOutput()->setRobotPolicy( 'noindex,nofollow' );
 531
 532                         global $wgSend404Code;
 533                         if ( $wgSend404Code ) {
 534                                 $context->getOutput()->setStatusCode( 404 );
 535                         }
 536
 537                         $context->getOutput()->showErrorPage( 'nosuchspecialpage', 'nospecialpagetext' );
 538
 539                         return false;
 540                 }
 541
 542                 if ( !$including ) {
 543                         // Narrow DB query expectations for this HTTP request
 544                         $trxLimits = $context->getConfig()->get( 'TrxProfilerLimits' );
 545                         $trxProfiler = Profiler::instance()->getTransactionProfiler();
 546                         if ( $context->getRequest()->wasPosted() && !$page->doesWrites() ) {
 547                                 $trxProfiler->setExpectations( $trxLimits['POST-nonwrite'], __METHOD__ );
 548                                 $context->getRequest()->markAsSafeRequest();
 549                         }
 550                 }
 551
 552                 // Page exists, set the context
 553                 $page->setContext( $context );
 554
 555                 if ( !$including ) {
 556                         // Redirect to canonical alias for GET commands
 557                         // Not for POST, we'd lose the post data, so it's best to just distribute
 558                         // the request. Such POST requests are possible for old extensions that
 559                         // generate self-links without being aware that their default name has
 560                         // changed.
 561                         if ( $name != $page->getLocalName() && !$context->getRequest()->wasPosted() ) {
 562                                 $query = $context->getRequest()->getQueryValues();
 563                                 unset( $query['title'] );
 564                                 $title = $page->getPageTitle( $par );
 565                                 $url = $title->getFullURL( $query );
 566                                 $context->getOutput()->redirect( $url );
 567
 568                                 return $title;
 569                         }
 570
 571                         // @phan-suppress-next-line PhanUndeclaredMethod
 572                         $context->setTitle( $page->getPageTitle( $par ) );
 573                 } elseif ( !$page->isIncludable() ) {
 574                         return false;
 575                 }
 576
 577                 $page->including( $including );
 578                 if ( $linkRenderer ) {
 579                         $page->setLinkRenderer( $linkRenderer );
 580                 }
 581
 582                 // Execute special page
 583                 $page->run( $par );
 584
 585                 return true;
 586         }
 587
 588         /**
 589          * Just like executePath() but will override global variables and execute
 590          * the page in "inclusion" mode. Returns true if the execution was
 591          * successful or false if there was no such special page, or a title object
 592          * if it was a redirect.
 593          *
 594          * Also saves the current $wgTitle, $wgOut, $wgRequest, $wgUser and $wgLang
 595          * variables so that the special page will get the context it'd expect on a
 596          * normal request, and then restores them to their previous values after.
 597          *
 598          * @param Title $title
 599          * @param IContextSource $context
 600          * @param LinkRenderer|null $linkRenderer (since 1.28)
 601          * @return string HTML fragment
 602          */
 603         public function capturePath(
 604                 Title $title, IContextSource $context, LinkRenderer $linkRenderer = null
 605         ) {
 606                 global $wgTitle, $wgOut, $wgRequest, $wgUser, $wgLang;
 607                 $main = RequestContext::getMain();
 608
 609                 // Save current globals and main context
 610                 $glob = [
 611                         'title' => $wgTitle,
 612                         'output' => $wgOut,
 613                         'request' => $wgRequest,
 614                         'user' => $wgUser,
 615                         'language' => $wgLang,
 616                 ];
 617                 $ctx = [
 618                         'title' => $main->getTitle(),
 619                         'output' => $main->getOutput(),
 620                         'request' => $main->getRequest(),
 621                         'user' => $main->getUser(),
 622                         'language' => $main->getLanguage(),
 623                 ];
 624                 if ( $main->canUseWikiPage() ) {
 625                         $ctx['wikipage'] = $main->getWikiPage();
 626                 }
 627
 628                 // Override
 629                 $wgTitle = $title;
 630                 $wgOut = $context->getOutput();
 631                 $wgRequest = $context->getRequest();
 632                 $wgUser = $context->getUser();
 633                 $wgLang = $context->getLanguage();
 634                 $main->setTitle( $title );
 635                 $main->setOutput( $context->getOutput() );
 636                 $main->setRequest( $context->getRequest() );
 637                 $main->setUser( $context->getUser() );
 638                 $main->setLanguage( $context->getLanguage() );
 639
 640                 // The useful part
 641                 $ret = $this->executePath( $title, $context, true, $linkRenderer );
 642
 643                 // Restore old globals and context
 644                 $wgTitle = $glob['title'];
 645                 $wgOut = $glob['output'];
 646                 $wgRequest = $glob['request'];
 647                 $wgUser = $glob['user'];
 648                 $wgLang = $glob['language'];
 649                 $main->setTitle( $ctx['title'] );
 650                 $main->setOutput( $ctx['output'] );
 651                 $main->setRequest( $ctx['request'] );
 652                 $main->setUser( $ctx['user'] );
 653                 $main->setLanguage( $ctx['language'] );
 654                 if ( isset( $ctx['wikipage'] ) ) {
 655                         $main->setWikiPage( $ctx['wikipage'] );
 656                 }
 657
 658                 return $ret;
 659         }
 660
 661         /**
 662          * Get the local name for a specified canonical name
 663          *
 664          * @param string $name
 665          * @param string|bool $subpage
 666          * @return string
 667          */
 668         public function getLocalNameFor( $name, $subpage = false ) {
 669                 $aliases = $this->contLang->getSpecialPageAliases();
 670                 $aliasList = $this->getAliasList();
 671
 672                 // Find the first alias that maps back to $name
 673                 if ( isset( $aliases[$name] ) ) {
 674                         $found = false;
 675                         foreach ( $aliases[$name] as $alias ) {
 676                                 $caseFoldedAlias = $this->contLang->caseFold( $alias );
 677                                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 678                                 if ( isset( $aliasList[$caseFoldedAlias] ) &&
 679                                         $aliasList[$caseFoldedAlias] === $name
 680                                 ) {
 681                                         $name = $alias;
 682                                         $found = true;
 683                                         break;
 684                                 }
 685                         }
 686                         if ( !$found ) {
 687                                 wfWarn( "Did not find a usable alias for special page '$name'. " .
 688                                         "It seems all defined aliases conflict?" );
 689                         }
 690                 } else {
 691                         // Check if someone misspelled the correct casing
 692                         if ( is_array( $aliases ) ) {
 693                                 foreach ( $aliases as $n => $values ) {
 694                                         if ( strcasecmp( $name, $n ) === 0 ) {
 695                                                 wfWarn( "Found alias defined for $n when searching for " .
 696                                                         "special page aliases for $name. Case mismatch?" );
 697                                                 return $this->getLocalNameFor( $n, $subpage );
 698                                         }
 699                                 }
 700                         }
 701
 702                         wfWarn( "Did not find alias for special page '$name'. " .
 703                                 "Perhaps no aliases are defined for it?" );
 704                 }
 705
 706                 if ( $subpage !== false && !is_null( $subpage ) ) {
 707                         // Make sure it's in dbkey form
 708                         $subpage = str_replace( ' ', '_', $subpage );
 709                         $name = "$name/$subpage";
 710                 }
 711
 712                 return $this->contLang->ucfirst( $name );
 713         }
 714
 715         /**
 716          * Get a title for a given alias
 717          *
 718          * @param string $alias
 719          * @return Title|null Title or null if there is no such alias
 720          */
 721         public function getTitleForAlias( $alias ) {
 722                 list( $name, $subpage ) = $this->resolveAlias( $alias );
 723                 if ( $name != null ) {
 724                         return SpecialPage::getTitleFor( $name, $subpage );
 725                 }
 726
 727                 return null;
 728         }
 729 }