includes/Wiki.php

   1 <?php
   2 /**
   3  * Helper class for the index.php entry point.
   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  */
  22
  23 /**
  24  * The MediaWiki class is the helper class for the index.php entry point.
  25  *
  26  * @internal documentation reviewed 15 Mar 2010
  27  */
  28 class MediaWiki {
  29
  30         /**
  31          * TODO: fold $output, etc, into this
  32          * @var IContextSource
  33          */
  34         private $context;
  35
  36         /**
  37          * @var string
  38          */
  39         private $performedAction = 'nosuchaction';
  40
  41         /**
  42          * @param $x null|WebRequest
  43          * @return WebRequest
  44          */
  45         public function request( WebRequest $x = null ) {
  46                 $old = $this->context->getRequest();
  47                 $this->context->setRequest( $x );
  48                 return $old;
  49         }
  50
  51         /**
  52          * @param $x null|OutputPage
  53          * @return OutputPage
  54          */
  55         public function output( OutputPage $x = null ) {
  56                 $old = $this->context->getOutput();
  57                 $this->context->setOutput( $x );
  58                 return $old;
  59         }
  60
  61         /**
  62          * @param IContextSource|null $context
  63          */
  64         public function __construct( IContextSource $context = null ) {
  65                 if ( !$context ) {
  66                         $context = RequestContext::getMain();
  67                 }
  68
  69                 $this->context = $context;
  70                 $this->context->setTitle( $this->parseTitle() );
  71         }
  72
  73         /**
  74          * Parse the request to get the Title object
  75          *
  76          * @return Title object to be $wgTitle
  77          */
  78         private function parseTitle() {
  79                 global $wgContLang;
  80
  81                 $request = $this->context->getRequest();
  82                 $curid = $request->getInt( 'curid' );
  83                 $title = $request->getVal( 'title' );
  84
  85                 if ( $request->getCheck( 'search' ) ) {
  86                         // Compatibility with old search URLs which didn't use Special:Search
  87                         // Just check for presence here, so blank requests still
  88                         // show the search page when using ugly URLs (bug 8054).
  89                         $ret = SpecialPage::getTitleFor( 'Search' );
  90                 } elseif ( $curid ) {
  91                         // URLs like this are generated by RC, because rc_title isn't always accurate
  92                         $ret = Title::newFromID( $curid );
  93                 } elseif ( $title == '' && $this->getAction() != 'delete' ) {
  94                         $ret = Title::newMainPage();
  95                 } else {
  96                         $ret = Title::newFromURL( $title );
  97                         // Alias NS_MEDIA page URLs to NS_FILE...we only use NS_MEDIA
  98                         // in wikitext links to tell Parser to make a direct file link
  99                         if ( !is_null( $ret ) && $ret->getNamespace() == NS_MEDIA ) {
 100                                 $ret = Title::makeTitle( NS_FILE, $ret->getDBkey() );
 101                         }
 102                         // Check variant links so that interwiki links don't have to worry
 103                         // about the possible different language variants
 104                         if ( count( $wgContLang->getVariants() ) > 1
 105                                 && !is_null( $ret ) && $ret->getArticleID() == 0 )
 106                         {
 107                                 $wgContLang->findVariantLink( $title, $ret );
 108                         }
 109                 }
 110                 // For non-special titles, check for implicit titles
 111                 if ( is_null( $ret ) || !$ret->isSpecialPage() ) {
 112                         // We can have urls with just ?diff=,?oldid= or even just ?diff=
 113                         $oldid = $request->getInt( 'oldid' );
 114                         $oldid = $oldid ? $oldid : $request->getInt( 'diff' );
 115                         // Allow oldid to override a changed or missing title
 116                         if ( $oldid ) {
 117                                 $rev = Revision::newFromId( $oldid );
 118                                 $ret = $rev ? $rev->getTitle() : $ret;
 119                         }
 120                 }
 121
 122                 if ( $ret === null || ( $ret->getDBkey() == '' && $ret->getInterwiki() == '' ) ) {
 123                         $ret = SpecialPage::getTitleFor( 'Badtitle' );
 124                 }
 125
 126                 return $ret;
 127         }
 128
 129         /**
 130          * Get the Title object that we'll be acting on, as specified in the WebRequest
 131          * @return Title
 132          */
 133         public function getTitle() {
 134                 if( $this->context->getTitle() === null ){
 135                         $this->context->setTitle( $this->parseTitle() );
 136                 }
 137                 return $this->context->getTitle();
 138         }
 139
 140         /**
 141          * Performs the request.
 142          * - bad titles
 143          * - read restriction
 144          * - local interwiki redirects
 145          * - redirect loop
 146          * - special pages
 147          * - normal pages
 148          *
 149          * @return void
 150          */
 151         private function performRequest() {
 152                 global $wgServer, $wgUsePathInfo, $wgTitle;
 153
 154                 wfProfileIn( __METHOD__ );
 155
 156                 $request = $this->context->getRequest();
 157                 $title = $this->context->getTitle();
 158                 $output = $this->context->getOutput();
 159                 $user = $this->context->getUser();
 160
 161                 if ( $request->getVal( 'printable' ) === 'yes' ) {
 162                         $output->setPrintable();
 163                 }
 164
 165                 $unused = null; // To pass it by reference
 166                 wfRunHooks( 'BeforeInitialize', array( &$title, &$unused, &$output, &$user, $request, $this ) );
 167
 168                 // Invalid titles. Bug 21776: The interwikis must redirect even if the page name is empty.
 169                 if ( is_null( $title ) || ( $title->getDBkey() == '' && $title->getInterwiki() == '' ) ||
 170                         $title->isSpecial( 'Badtitle' ) )
 171                 {
 172                         $this->context->setTitle( SpecialPage::getTitleFor( 'Badtitle' ) );
 173                         wfProfileOut( __METHOD__ );
 174                         throw new ErrorPageError( 'badtitle', 'badtitletext' );
 175                 }
 176
 177                 // Check user's permissions to read this page.
 178                 // We have to check here to catch special pages etc.
 179                 // We will check again in Article::view().
 180                 $permErrors = $title->getUserPermissionsErrors( 'read', $user );
 181                 if ( count( $permErrors ) ) {
 182                         // Bug 32276: allowing the skin to generate output with $wgTitle or
 183                         // $this->context->title set to the input title would allow anonymous users to
 184                         // determine whether a page exists, potentially leaking private data. In fact, the
 185                         // curid and oldid request  parameters would allow page titles to be enumerated even
 186                         // when they are not guessable. So we reset the title to Special:Badtitle before the
 187                         // permissions error is displayed.
 188                         //
 189                         // The skin mostly uses $this->context->getTitle() these days, but some extensions
 190                         // still use $wgTitle.
 191
 192                         $badTitle = SpecialPage::getTitleFor( 'Badtitle' );
 193                         $this->context->setTitle( $badTitle );
 194                         $wgTitle = $badTitle;
 195
 196                         wfProfileOut( __METHOD__ );
 197                         throw new PermissionsError( 'read', $permErrors );
 198                 }
 199
 200                 $pageView = false; // was an article or special page viewed?
 201
 202                 // Interwiki redirects
 203                 if ( $title->getInterwiki() != '' ) {
 204                         $rdfrom = $request->getVal( 'rdfrom' );
 205                         if ( $rdfrom ) {
 206                                 $url = $title->getFullURL( 'rdfrom=' . urlencode( $rdfrom ) );
 207                         } else {
 208                                 $query = $request->getValues();
 209                                 unset( $query['title'] );
 210                                 $url = $title->getFullURL( $query );
 211                         }
 212                         // Check for a redirect loop
 213                         if ( !preg_match( '/^' . preg_quote( $wgServer, '/' ) . '/', $url )
 214                                 && $title->isLocal() )
 215                         {
 216                                 // 301 so google et al report the target as the actual url.
 217                                 $output->redirect( $url, 301 );
 218                         } else {
 219                                 $this->context->setTitle( SpecialPage::getTitleFor( 'Badtitle' ) );
 220                                 wfProfileOut( __METHOD__ );
 221                                 throw new ErrorPageError( 'badtitle', 'badtitletext' );
 222                         }
 223                 // Redirect loops, no title in URL, $wgUsePathInfo URLs, and URLs with a variant
 224                 } elseif ( $request->getVal( 'action', 'view' ) == 'view' && !$request->wasPosted()
 225                         && ( $request->getVal( 'title' ) === null ||
 226                                 $title->getPrefixedDBKey() != $request->getVal( 'title' ) )
 227                         && !count( $request->getValueNames( array( 'action', 'title' ) ) )
 228                         && wfRunHooks( 'TestCanonicalRedirect', array( $request, $title, $output ) ) )
 229                 {
 230                         if ( $title->isSpecialPage() ) {
 231                                 list( $name, $subpage ) = SpecialPageFactory::resolveAlias( $title->getDBkey() );
 232                                 if ( $name ) {
 233                                         $title = SpecialPage::getTitleFor( $name, $subpage );
 234                                 }
 235                         }
 236                         $targetUrl = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
 237                         // Redirect to canonical url, make it a 301 to allow caching
 238                         if ( $targetUrl == $request->getFullRequestURL() ) {
 239                                 $message = "Redirect loop detected!\n\n" .
 240                                         "This means the wiki got confused about what page was " .
 241                                         "requested; this sometimes happens when moving a wiki " .
 242                                         "to a new server or changing the server configuration.\n\n";
 243
 244                                 if ( $wgUsePathInfo ) {
 245                                         $message .= "The wiki is trying to interpret the page " .
 246                                                 "title from the URL path portion (PATH_INFO), which " .
 247                                                 "sometimes fails depending on the web server. Try " .
 248                                                 "setting \"\$wgUsePathInfo = false;\" in your " .
 249                                                 "LocalSettings.php, or check that \$wgArticlePath " .
 250                                                 "is correct.";
 251                                 } else {
 252                                         $message .= "Your web server was detected as possibly not " .
 253                                                 "supporting URL path components (PATH_INFO) correctly; " .
 254                                                 "check your LocalSettings.php for a customized " .
 255                                                 "\$wgArticlePath setting and/or toggle \$wgUsePathInfo " .
 256                                                 "to true.";
 257                                 }
 258                                 throw new HttpError( 500, $message );
 259                         } else {
 260                                 $output->setSquidMaxage( 1200 );
 261                                 $output->redirect( $targetUrl, '301' );
 262                         }
 263                 // Special pages
 264                 } elseif ( NS_SPECIAL == $title->getNamespace() ) {
 265                         $pageView = true;
 266                         // Actions that need to be made when we have a special pages
 267                         SpecialPageFactory::executePath( $title, $this->context );
 268                 } else {
 269                         // ...otherwise treat it as an article view. The article
 270                         // may be a redirect to another article or URL.
 271                         $article = $this->initializeArticle();
 272                         if ( is_object( $article ) ) {
 273                                 $pageView = true;
 274                                 /**
 275                                  * $wgArticle is deprecated, do not use it.
 276                                  * This will be removed entirely in 1.20.
 277                                  * @deprecated since 1.18
 278                                  */
 279                                 global $wgArticle;
 280                                 $wgArticle = $article;
 281
 282                                 $this->performAction( $article );
 283                         } elseif ( is_string( $article ) ) {
 284                                 $output->redirect( $article );
 285                         } else {
 286                                 wfProfileOut( __METHOD__ );
 287                                 throw new MWException( "Shouldn't happen: MediaWiki::initializeArticle() returned neither an object nor a URL" );
 288                         }
 289                 }
 290
 291                 if ( $pageView ) {
 292                         // Promote user to any groups they meet the criteria for
 293                         $user->addAutopromoteOnceGroups( 'onView' );
 294                 }
 295
 296                 wfProfileOut( __METHOD__ );
 297         }
 298
 299         /**
 300          * Create an Article object of the appropriate class for the given page.
 301          *
 302          * @deprecated in 1.18; use Article::newFromTitle() instead
 303          * @param $title Title
 304          * @param $context IContextSource
 305          * @return Article object
 306          */
 307         public static function articleFromTitle( $title, IContextSource $context ) {
 308                 wfDeprecated( __METHOD__, '1.18' );
 309                 return Article::newFromTitle( $title, $context );
 310         }
 311
 312         /**
 313          * Returns the action that will be executed, not necessarily the one passed
 314          * passed through the "action" parameter. Actions disabled in
 315          * $wgDisabledActions will be replaced by "nosuchaction".
 316          *
 317          * The return value is merely a suggestion, not the actually performed action,
 318          * which may be different. The actually performed action is determined by performAction().
 319          * Requests like action=nonsense will make this function return "nonsense".
 320          * Use getPerformedAction() to get the performed action.
 321          *
 322          * @return string: action
 323          */
 324         public function getAction() {
 325                 global $wgDisabledActions;
 326
 327                 $request = $this->context->getRequest();
 328                 $action = $request->getVal( 'action', 'view' );
 329
 330                 // Check for disabled actions
 331                 if ( in_array( $action, $wgDisabledActions ) ) {
 332                         return 'nosuchaction';
 333                 }
 334
 335                 // Workaround for bug #20966: inability of IE to provide an action dependent
 336                 // on which submit button is clicked.
 337                 if ( $action === 'historysubmit' ) {
 338                         if ( $request->getBool( 'revisiondelete' ) ) {
 339                                 return 'revisiondelete';
 340                         } else {
 341                                 return 'view';
 342                         }
 343                 } elseif ( $action == 'editredlink' ) {
 344                         return 'edit';
 345                 }
 346
 347                 return $action;
 348         }
 349
 350         /**
 351          * Initialize the main Article object for "standard" actions (view, etc)
 352          * Create an Article object for the page, following redirects if needed.
 353          *
 354          * @return mixed an Article, or a string to redirect to another URL
 355          */
 356         private function initializeArticle() {
 357                 global $wgDisableHardRedirects;
 358
 359                 wfProfileIn( __METHOD__ );
 360
 361                 $title = $this->context->getTitle();
 362                 $article = Article::newFromTitle( $title, $this->context );
 363                 $this->context->setWikiPage( $article->getPage() );
 364                 // NS_MEDIAWIKI has no redirects.
 365                 // It is also used for CSS/JS, so performance matters here...
 366                 if ( $title->getNamespace() == NS_MEDIAWIKI ) {
 367                         wfProfileOut( __METHOD__ );
 368                         return $article;
 369                 }
 370
 371                 $request = $this->context->getRequest();
 372
 373                 // Namespace might change when using redirects
 374                 // Check for redirects ...
 375                 $action = $request->getVal( 'action', 'view' );
 376                 $file = ( $title->getNamespace() == NS_FILE ) ? $article->getFile() : null;
 377                 if ( ( $action == 'view' || $action == 'render' )       // ... for actions that show content
 378                         && !$request->getVal( 'oldid' ) &&    // ... and are not old revisions
 379                         !$request->getVal( 'diff' ) &&    // ... and not when showing diff
 380                         $request->getVal( 'redirect' ) != 'no' &&       // ... unless explicitly told not to
 381                         // ... and the article is not a non-redirect image page with associated file
 382                         !( is_object( $file ) && $file->exists() && !$file->getRedirected() ) )
 383                 {
 384                         // Give extensions a change to ignore/handle redirects as needed
 385                         $ignoreRedirect = $target = false;
 386
 387                         wfRunHooks( 'InitializeArticleMaybeRedirect',
 388                                 array( &$title, &$request, &$ignoreRedirect, &$target, &$article ) );
 389
 390                         // Follow redirects only for... redirects.
 391                         // If $target is set, then a hook wanted to redirect.
 392                         if ( !$ignoreRedirect && ( $target || $article->isRedirect() ) ) {
 393                                 // Is the target already set by an extension?
 394                                 $target = $target ? $target : $article->followRedirect();
 395                                 if ( is_string( $target ) ) {
 396                                         if ( !$wgDisableHardRedirects ) {
 397                                                 // we'll need to redirect
 398                                                 wfProfileOut( __METHOD__ );
 399                                                 return $target;
 400                                         }
 401                                 }
 402                                 if ( is_object( $target ) ) {
 403                                         // Rewrite environment to redirected article
 404                                         $rarticle = Article::newFromTitle( $target, $this->context );
 405                                         $rarticle->loadPageData();
 406                                         if ( $rarticle->exists() || ( is_object( $file ) && !$file->isLocal() ) ) {
 407                                                 $rarticle->setRedirectedFrom( $title );
 408                                                 $article = $rarticle;
 409                                                 $this->context->setTitle( $target );
 410                                                 $this->context->setWikiPage( $article->getPage() );
 411                                         }
 412                                 }
 413                         } else {
 414                                 $this->context->setTitle( $article->getTitle() );
 415                                 $this->context->setWikiPage( $article->getPage() );
 416                         }
 417                 }
 418
 419                 wfProfileOut( __METHOD__ );
 420                 return $article;
 421         }
 422
 423         /**
 424          * Cleaning up request by doing deferred updates, DB transaction, and the output
 425          */
 426         public function finalCleanup() {
 427                 wfProfileIn( __METHOD__ );
 428                 // Now commit any transactions, so that unreported errors after
 429                 // output() don't roll back the whole DB transaction
 430                 $factory = wfGetLBFactory();
 431                 $factory->commitMasterChanges();
 432                 // Output everything!
 433                 $this->context->getOutput()->output();
 434                 // Do any deferred jobs
 435                 DeferredUpdates::doUpdates( 'commit' );
 436                 $this->doJobs();
 437                 wfProfileOut( __METHOD__ );
 438         }
 439
 440         /**
 441          * Do a job from the job queue
 442          */
 443         private function doJobs() {
 444                 global $wgJobRunRate;
 445
 446                 if ( $wgJobRunRate <= 0 || wfReadOnly() ) {
 447                         return;
 448                 }
 449                 if ( $wgJobRunRate < 1 ) {
 450                         $max = mt_getrandmax();
 451                         if ( mt_rand( 0, $max ) > $max * $wgJobRunRate ) {
 452                                 return;
 453                         }
 454                         $n = 1;
 455                 } else {
 456                         $n = intval( $wgJobRunRate );
 457                 }
 458
 459                 while ( $n-- && false != ( $job = Job::pop() ) ) {
 460                         $output = $job->toString() . "\n";
 461                         $t = -wfTime();
 462                         $success = $job->run();
 463                         $t += wfTime();
 464                         $t = round( $t * 1000 );
 465                         if ( !$success ) {
 466                                 $output .= "Error: " . $job->getLastError() . ", Time: $t ms\n";
 467                         } else {
 468                                 $output .= "Success, Time: $t ms\n";
 469                         }
 470                         wfDebugLog( 'jobqueue', $output );
 471                 }
 472         }
 473
 474         /**
 475          * Ends this task peacefully
 476          */
 477         public function restInPeace() {
 478                 MessageCache::logMessages();
 479                 wfLogProfilingData();
 480                 // Commit and close up!
 481                 $factory = wfGetLBFactory();
 482                 $factory->commitMasterChanges();
 483                 $factory->shutdown();
 484                 wfDebug( "Request ended normally\n" );
 485         }
 486
 487         /**
 488          * Perform one of the "standard" actions
 489          *
 490          * @param $article Article
 491          */
 492         private function performAction( Page $article ) {
 493                 global $wgSquidMaxage;
 494
 495                 wfProfileIn( __METHOD__ );
 496
 497                 $request = $this->context->getRequest();
 498                 $output = $this->context->getOutput();
 499                 $title = $this->context->getTitle();
 500                 $user = $this->context->getUser();
 501
 502                 if ( !wfRunHooks( 'MediaWikiPerformAction',
 503                         array( $output, $article, $title, $user, $request, $this ) ) )
 504                 {
 505                         wfProfileOut( __METHOD__ );
 506                         return;
 507                 }
 508
 509                 $act = $this->getAction();
 510
 511                 $action = Action::factory( $act, $article );
 512                 if ( $action instanceof Action ) {
 513                         $this->performedAction = $act;
 514                         $action->show();
 515                         wfProfileOut( __METHOD__ );
 516                         return;
 517                 }
 518
 519                 switch( $act ) {
 520                         case 'view':
 521                                 $output->setSquidMaxage( $wgSquidMaxage );
 522                                 $this->performedAction = $act;
 523                                 $article->view();
 524                                 break;
 525                         case 'delete':
 526                         case 'protect':
 527                         case 'unprotect':
 528                         case 'render':
 529                                 $this->performedAction = $act;
 530                                 $article->$act();
 531                                 break;
 532                         case 'submit':
 533                                 if ( session_id() == '' ) {
 534                                         // Send a cookie so anons get talk message notifications
 535                                         wfSetupSession();
 536                                 }
 537                                 // Continue...
 538                         case 'edit':
 539                                 if ( wfRunHooks( 'CustomEditor', array( $article, $user ) ) ) {
 540                                         $this->performedAction = 'edit';
 541                                         if ( ExternalEdit::useExternalEngine( $this->context, 'edit' )
 542                                                 && $act == 'edit' && !$request->getVal( 'section' )
 543                                                 && !$request->getVal( 'oldid' ) )
 544                                         {
 545                                                 $extedit = new ExternalEdit( $this->context );
 546                                                 $extedit->execute();
 547                                         } else {
 548                                                 $editor = new EditPage( $article );
 549                                                 $editor->edit();
 550                                         }
 551                                 }
 552                                 break;
 553                         default:
 554                                 if ( wfRunHooks( 'UnknownAction', array( $act, $article ) ) ) {
 555                                         $this->performedAction = 'nosuchaction';
 556                                         $output->showErrorPage( 'nosuchaction', 'nosuchactiontext' );
 557                                 }
 558                 }
 559                 wfProfileOut( __METHOD__ );
 560         }
 561
 562         /**
 563          * Returns the real action as determined by performAction.
 564          * Do not use internally in this class as it depends on the actions by this class.
 565          *
 566          * @since 1.19
 567          *
 568          * @return string: action
 569          */
 570         public function getPerformedAction() {
 571                 return $this->performedAction;
 572         }
 573
 574         /**
 575          * Run the current MediaWiki instance
 576          * index.php just calls this
 577          */
 578         public function run() {
 579                 try {
 580                         $this->checkMaxLag();
 581                         $this->main();
 582                         $this->restInPeace();
 583                 } catch ( Exception $e ) {
 584                         MWExceptionHandler::handle( $e );
 585                 }
 586         }
 587
 588         /**
 589          * Checks if the request should abort due to a lagged server,
 590          * for given maxlag parameter.
 591          * @return bool
 592          */
 593         private function checkMaxLag() {
 594                 global $wgShowHostnames;
 595
 596                 wfProfileIn( __METHOD__ );
 597                 $maxLag = $this->context->getRequest()->getVal( 'maxlag' );
 598                 if ( !is_null( $maxLag ) ) {
 599                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 600                         if ( $lag > $maxLag ) {
 601                                 $resp = $this->context->getRequest()->response();
 602                                 $resp->header( 'HTTP/1.1 503 Service Unavailable' );
 603                                 $resp->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 604                                 $resp->header( 'X-Database-Lag: ' . intval( $lag ) );
 605                                 $resp->header( 'Content-Type: text/plain' );
 606                                 if( $wgShowHostnames ) {
 607                                         echo "Waiting for $host: $lag seconds lagged\n";
 608                                 } else {
 609                                         echo "Waiting for a database server: $lag seconds lagged\n";
 610                                 }
 611
 612                                 wfProfileOut( __METHOD__ );
 613
 614                                 exit;
 615                         }
 616                 }
 617                 wfProfileOut( __METHOD__ );
 618                 return true;
 619         }
 620
 621         private function main() {
 622                 global $wgUseFileCache, $wgTitle, $wgUseAjax;
 623
 624                 wfProfileIn( __METHOD__ );
 625
 626                 # Set title from request parameters
 627                 $wgTitle = $this->getTitle();
 628                 $action = $this->getAction();
 629
 630                 # Send Ajax requests to the Ajax dispatcher.
 631                 if ( $wgUseAjax && $action == 'ajax' ) {
 632                         $dispatcher = new AjaxDispatcher();
 633                         $dispatcher->performAction();
 634                         wfProfileOut( __METHOD__ );
 635                         return;
 636                 }
 637
 638                 if ( $wgUseFileCache && $this->getTitle()->getNamespace() >= 0 ) {
 639                         wfProfileIn( 'main-try-filecache' );
 640                         if ( HTMLFileCache::useFileCache( $this->context ) ) {
 641                                 /* Try low-level file cache hit */
 642                                 $cache = HTMLFileCache::newFromTitle( $this->getTitle(), $action );
 643                                 if ( $cache->isCacheGood( /* Assume up to date */ ) ) {
 644                                         /* Check incoming headers to see if client has this cached */
 645                                         $timestamp = $cache->cacheTimestamp();
 646                                         if ( !$this->context->getOutput()->checkLastModified( $timestamp ) ) {
 647                                                 $cache->loadFromFileCache( $this->context );
 648                                         }
 649                                         # Do any stats increment/watchlist stuff
 650                                         $this->context->getWikiPage()->doViewUpdates( $this->context->getUser() );
 651                                         # Tell OutputPage that output is taken care of
 652                                         $this->context->getOutput()->disable();
 653                                         wfProfileOut( 'main-try-filecache' );
 654                                         wfProfileOut( __METHOD__ );
 655                                         return;
 656                                 }
 657                         }
 658                         wfProfileOut( 'main-try-filecache' );
 659                 }
 660
 661                 $this->performRequest();
 662                 $this->finalCleanup();
 663
 664                 wfProfileOut( __METHOD__ );
 665         }
 666 }