includes/MediaWiki.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          * @var IContextSource
  31          */
  32         private $context;
  33
  34         /**
  35          * @var Config
  36          */
  37         private $config;
  38
  39         /**
  40          * @param IContextSource|null $context
  41          */
  42         public function __construct( IContextSource $context = null ) {
  43                 if ( !$context ) {
  44                         $context = RequestContext::getMain();
  45                 }
  46
  47                 $this->context = $context;
  48                 $this->config = $context->getConfig();
  49         }
  50
  51         /**
  52          * Parse the request to get the Title object
  53          *
  54          * @return Title Title object to be $wgTitle
  55          */
  56         private function parseTitle() {
  57                 global $wgContLang;
  58
  59                 $request = $this->context->getRequest();
  60                 $curid = $request->getInt( 'curid' );
  61                 $title = $request->getVal( 'title' );
  62                 $action = $request->getVal( 'action' );
  63
  64                 if ( $request->getCheck( 'search' ) ) {
  65                         // Compatibility with old search URLs which didn't use Special:Search
  66                         // Just check for presence here, so blank requests still
  67                         // show the search page when using ugly URLs (bug 8054).
  68                         $ret = SpecialPage::getTitleFor( 'Search' );
  69                 } elseif ( $curid ) {
  70                         // URLs like this are generated by RC, because rc_title isn't always accurate
  71                         $ret = Title::newFromID( $curid );
  72                 } else {
  73                         $ret = Title::newFromURL( $title );
  74                         // Alias NS_MEDIA page URLs to NS_FILE...we only use NS_MEDIA
  75                         // in wikitext links to tell Parser to make a direct file link
  76                         if ( !is_null( $ret ) && $ret->getNamespace() == NS_MEDIA ) {
  77                                 $ret = Title::makeTitle( NS_FILE, $ret->getDBkey() );
  78                         }
  79                         // Check variant links so that interwiki links don't have to worry
  80                         // about the possible different language variants
  81                         if ( count( $wgContLang->getVariants() ) > 1
  82                                 && !is_null( $ret ) && $ret->getArticleID() == 0
  83                         ) {
  84                                 $wgContLang->findVariantLink( $title, $ret );
  85                         }
  86                 }
  87
  88                 // If title is not provided, always allow oldid and diff to set the title.
  89                 // If title is provided, allow oldid and diff to override the title, unless
  90                 // we are talking about a special page which might use these parameters for
  91                 // other purposes.
  92                 if ( $ret === null || !$ret->isSpecialPage() ) {
  93                         // We can have urls with just ?diff=,?oldid= or even just ?diff=
  94                         $oldid = $request->getInt( 'oldid' );
  95                         $oldid = $oldid ? $oldid : $request->getInt( 'diff' );
  96                         // Allow oldid to override a changed or missing title
  97                         if ( $oldid ) {
  98                                 $rev = Revision::newFromId( $oldid );
  99                                 $ret = $rev ? $rev->getTitle() : $ret;
 100                         }
 101                 }
 102
 103                 // Use the main page as default title if nothing else has been provided
 104                 if ( $ret === null
 105                         && strval( $title ) === ''
 106                         && !$request->getCheck( 'curid' )
 107                         && $action !== 'delete'
 108                 ) {
 109                         $ret = Title::newMainPage();
 110                 }
 111
 112                 if ( $ret === null || ( $ret->getDBkey() == '' && !$ret->isExternal() ) ) {
 113                         $ret = SpecialPage::getTitleFor( 'Badtitle' );
 114                 }
 115
 116                 return $ret;
 117         }
 118
 119         /**
 120          * Get the Title object that we'll be acting on, as specified in the WebRequest
 121          * @return Title
 122          */
 123         public function getTitle() {
 124                 if ( !$this->context->hasTitle() ) {
 125                         $this->context->setTitle( $this->parseTitle() );
 126                 }
 127                 return $this->context->getTitle();
 128         }
 129
 130         /**
 131          * Returns the name of the action that will be executed.
 132          *
 133          * @return string Action
 134          */
 135         public function getAction() {
 136                 static $action = null;
 137
 138                 if ( $action === null ) {
 139                         $action = Action::getActionName( $this->context );
 140                 }
 141
 142                 return $action;
 143         }
 144
 145         /**
 146          * Performs the request.
 147          * - bad titles
 148          * - read restriction
 149          * - local interwiki redirects
 150          * - redirect loop
 151          * - special pages
 152          * - normal pages
 153          *
 154          * @throws MWException|PermissionsError|BadTitleError|HttpError
 155          * @return void
 156          */
 157         private function performRequest() {
 158                 global $wgTitle;
 159
 160
 161                 $request = $this->context->getRequest();
 162                 $requestTitle = $title = $this->context->getTitle();
 163                 $output = $this->context->getOutput();
 164                 $user = $this->context->getUser();
 165
 166                 if ( $request->getVal( 'printable' ) === 'yes' ) {
 167                         $output->setPrintable();
 168                 }
 169
 170                 $unused = null; // To pass it by reference
 171                 Hooks::run( 'BeforeInitialize', array( &$title, &$unused, &$output, &$user, $request, $this ) );
 172
 173                 // Invalid titles. Bug 21776: The interwikis must redirect even if the page name is empty.
 174                 if ( is_null( $title ) || ( $title->getDBkey() == '' && !$title->isExternal() )
 175                         || $title->isSpecial( 'Badtitle' )
 176                 ) {
 177                         $this->context->setTitle( SpecialPage::getTitleFor( 'Badtitle' ) );
 178                         throw new BadTitleError();
 179                 }
 180
 181                 // Check user's permissions to read this page.
 182                 // We have to check here to catch special pages etc.
 183                 // We will check again in Article::view().
 184                 $permErrors = $title->isSpecial( 'RunJobs' )
 185                         ? array() // relies on HMAC key signature alone
 186                         : $title->getUserPermissionsErrors( 'read', $user );
 187                 if ( count( $permErrors ) ) {
 188                         // Bug 32276: allowing the skin to generate output with $wgTitle or
 189                         // $this->context->title set to the input title would allow anonymous users to
 190                         // determine whether a page exists, potentially leaking private data. In fact, the
 191                         // curid and oldid request  parameters would allow page titles to be enumerated even
 192                         // when they are not guessable. So we reset the title to Special:Badtitle before the
 193                         // permissions error is displayed.
 194                         //
 195                         // The skin mostly uses $this->context->getTitle() these days, but some extensions
 196                         // still use $wgTitle.
 197
 198                         $badTitle = SpecialPage::getTitleFor( 'Badtitle' );
 199                         $this->context->setTitle( $badTitle );
 200                         $wgTitle = $badTitle;
 201
 202                         throw new PermissionsError( 'read', $permErrors );
 203                 }
 204
 205                 $pageView = false; // was an article or special page viewed?
 206
 207                 // Interwiki redirects
 208                 if ( $title->isExternal() ) {
 209                         $rdfrom = $request->getVal( 'rdfrom' );
 210                         if ( $rdfrom ) {
 211                                 $url = $title->getFullURL( array( 'rdfrom' => $rdfrom ) );
 212                         } else {
 213                                 $query = $request->getValues();
 214                                 unset( $query['title'] );
 215                                 $url = $title->getFullURL( $query );
 216                         }
 217                         // Check for a redirect loop
 218                         if ( !preg_match( '/^' . preg_quote( $this->config->get( 'Server' ), '/' ) . '/', $url )
 219                                 && $title->isLocal()
 220                         ) {
 221                                 // 301 so google et al report the target as the actual url.
 222                                 $output->redirect( $url, 301 );
 223                         } else {
 224                                 $this->context->setTitle( SpecialPage::getTitleFor( 'Badtitle' ) );
 225                                 throw new BadTitleError();
 226                         }
 227                 // Redirect loops, no title in URL, $wgUsePathInfo URLs, and URLs with a variant
 228                 } elseif ( $request->getVal( 'action', 'view' ) == 'view' && !$request->wasPosted()
 229                         && ( $request->getVal( 'title' ) === null
 230                                 || $title->getPrefixedDBkey() != $request->getVal( 'title' ) )
 231                         && !count( $request->getValueNames( array( 'action', 'title' ) ) )
 232                         && Hooks::run( 'TestCanonicalRedirect', array( $request, $title, $output ) )
 233                 ) {
 234                         if ( $title->isSpecialPage() ) {
 235                                 list( $name, $subpage ) = SpecialPageFactory::resolveAlias( $title->getDBkey() );
 236                                 if ( $name ) {
 237                                         $title = SpecialPage::getTitleFor( $name, $subpage );
 238                                 }
 239                         }
 240                         $targetUrl = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
 241                         // Redirect to canonical url, make it a 301 to allow caching
 242                         if ( $targetUrl == $request->getFullRequestURL() ) {
 243                                 $message = "Redirect loop detected!\n\n" .
 244                                         "This means the wiki got confused about what page was " .
 245                                         "requested; this sometimes happens when moving a wiki " .
 246                                         "to a new server or changing the server configuration.\n\n";
 247
 248                                 if ( $this->config->get( 'UsePathInfo' ) ) {
 249                                         $message .= "The wiki is trying to interpret the page " .
 250                                                 "title from the URL path portion (PATH_INFO), which " .
 251                                                 "sometimes fails depending on the web server. Try " .
 252                                                 "setting \"\$wgUsePathInfo = false;\" in your " .
 253                                                 "LocalSettings.php, or check that \$wgArticlePath " .
 254                                                 "is correct.";
 255                                 } else {
 256                                         $message .= "Your web server was detected as possibly not " .
 257                                                 "supporting URL path components (PATH_INFO) correctly; " .
 258                                                 "check your LocalSettings.php for a customized " .
 259                                                 "\$wgArticlePath setting and/or toggle \$wgUsePathInfo " .
 260                                                 "to true.";
 261                                 }
 262                                 throw new HttpError( 500, $message );
 263                         } else {
 264                                 $output->setSquidMaxage( 1200 );
 265                                 $output->redirect( $targetUrl, '301' );
 266                         }
 267                 // Special pages
 268                 } elseif ( NS_SPECIAL == $title->getNamespace() ) {
 269                         $pageView = true;
 270                         // Actions that need to be made when we have a special pages
 271                         SpecialPageFactory::executePath( $title, $this->context );
 272                 } else {
 273                         // ...otherwise treat it as an article view. The article
 274                         // may be a redirect to another article or URL.
 275                         $article = $this->initializeArticle();
 276                         if ( is_object( $article ) ) {
 277                                 $pageView = true;
 278                                 $this->performAction( $article, $requestTitle );
 279                         } elseif ( is_string( $article ) ) {
 280                                 $output->redirect( $article );
 281                         } else {
 282                                 throw new MWException( "Shouldn't happen: MediaWiki::initializeArticle()"
 283                                         . " returned neither an object nor a URL" );
 284                         }
 285                 }
 286
 287                 if ( $pageView ) {
 288                         // Promote user to any groups they meet the criteria for
 289                         $user->addAutopromoteOnceGroups( 'onView' );
 290                 }
 291
 292         }
 293
 294         /**
 295          * Initialize the main Article object for "standard" actions (view, etc)
 296          * Create an Article object for the page, following redirects if needed.
 297          *
 298          * @return mixed An Article, or a string to redirect to another URL
 299          */
 300         private function initializeArticle() {
 301
 302                 $title = $this->context->getTitle();
 303                 if ( $this->context->canUseWikiPage() ) {
 304                         // Try to use request context wiki page, as there
 305                         // is already data from db saved in per process
 306                         // cache there from this->getAction() call.
 307                         $page = $this->context->getWikiPage();
 308                         $article = Article::newFromWikiPage( $page, $this->context );
 309                 } else {
 310                         // This case should not happen, but just in case.
 311                         $article = Article::newFromTitle( $title, $this->context );
 312                         $this->context->setWikiPage( $article->getPage() );
 313                 }
 314
 315                 // NS_MEDIAWIKI has no redirects.
 316                 // It is also used for CSS/JS, so performance matters here...
 317                 if ( $title->getNamespace() == NS_MEDIAWIKI ) {
 318                         return $article;
 319                 }
 320
 321                 $request = $this->context->getRequest();
 322
 323                 // Namespace might change when using redirects
 324                 // Check for redirects ...
 325                 $action = $request->getVal( 'action', 'view' );
 326                 $file = ( $title->getNamespace() == NS_FILE ) ? $article->getFile() : null;
 327                 if ( ( $action == 'view' || $action == 'render' ) // ... for actions that show content
 328                         && !$request->getVal( 'oldid' ) // ... and are not old revisions
 329                         && !$request->getVal( 'diff' ) // ... and not when showing diff
 330                         && $request->getVal( 'redirect' ) != 'no' // ... unless explicitly told not to
 331                         // ... and the article is not a non-redirect image page with associated file
 332                         && !( is_object( $file ) && $file->exists() && !$file->getRedirected() )
 333                 ) {
 334                         // Give extensions a change to ignore/handle redirects as needed
 335                         $ignoreRedirect = $target = false;
 336
 337                         Hooks::run( 'InitializeArticleMaybeRedirect',
 338                                 array( &$title, &$request, &$ignoreRedirect, &$target, &$article ) );
 339
 340                         // Follow redirects only for... redirects.
 341                         // If $target is set, then a hook wanted to redirect.
 342                         if ( !$ignoreRedirect && ( $target || $article->isRedirect() ) ) {
 343                                 // Is the target already set by an extension?
 344                                 $target = $target ? $target : $article->followRedirect();
 345                                 if ( is_string( $target ) ) {
 346                                         if ( !$this->config->get( 'DisableHardRedirects' ) ) {
 347                                                 // we'll need to redirect
 348                                                 return $target;
 349                                         }
 350                                 }
 351                                 if ( is_object( $target ) ) {
 352                                         // Rewrite environment to redirected article
 353                                         $rarticle = Article::newFromTitle( $target, $this->context );
 354                                         $rarticle->loadPageData();
 355                                         if ( $rarticle->exists() || ( is_object( $file ) && !$file->isLocal() ) ) {
 356                                                 $rarticle->setRedirectedFrom( $title );
 357                                                 $article = $rarticle;
 358                                                 $this->context->setTitle( $target );
 359                                                 $this->context->setWikiPage( $article->getPage() );
 360                                         }
 361                                 }
 362                         } else {
 363                                 $this->context->setTitle( $article->getTitle() );
 364                                 $this->context->setWikiPage( $article->getPage() );
 365                         }
 366                 }
 367
 368                 return $article;
 369         }
 370
 371         /**
 372          * Perform one of the "standard" actions
 373          *
 374          * @param Page $page
 375          * @param Title $requestTitle The original title, before any redirects were applied
 376          */
 377         private function performAction( Page $page, Title $requestTitle ) {
 378
 379                 $request = $this->context->getRequest();
 380                 $output = $this->context->getOutput();
 381                 $title = $this->context->getTitle();
 382                 $user = $this->context->getUser();
 383
 384                 if ( !Hooks::run( 'MediaWikiPerformAction',
 385                                 array( $output, $page, $title, $user, $request, $this ) )
 386                 ) {
 387                         return;
 388                 }
 389
 390                 $act = $this->getAction();
 391
 392                 $action = Action::factory( $act, $page, $this->context );
 393
 394                 if ( $action instanceof Action ) {
 395                         # Let Squid cache things if we can purge them.
 396                         if ( $this->config->get( 'UseSquid' ) &&
 397                                 in_array( $request->getFullRequestURL(), $requestTitle->getSquidURLs() )
 398                         ) {
 399                                 $output->setSquidMaxage( $this->config->get( 'SquidMaxage' ) );
 400                         }
 401
 402                         $action->show();
 403                         return;
 404                 }
 405
 406                 if ( Hooks::run( 'UnknownAction', array( $request->getVal( 'action', 'view' ), $page ) ) ) {
 407                         $output->setStatusCode( 404 );
 408                         $output->showErrorPage( 'nosuchaction', 'nosuchactiontext' );
 409                 }
 410
 411         }
 412
 413         /**
 414          * Run the current MediaWiki instance
 415          * index.php just calls this
 416          */
 417         public function run() {
 418                 try {
 419                         $this->checkMaxLag();
 420                         try {
 421                                 $this->main();
 422                         } catch ( ErrorPageError $e ) {
 423                                 // Bug 62091: while exceptions are convenient to bubble up GUI errors,
 424                                 // they are not internal application faults. As with normal requests, this
 425                                 // should commit, print the output, do deferred updates, jobs, and profiling.
 426                                 wfGetLBFactory()->commitMasterChanges();
 427                                 $e->report(); // display the GUI error
 428                         }
 429                         if ( function_exists( 'fastcgi_finish_request' ) ) {
 430                                 fastcgi_finish_request();
 431                         }
 432                         $this->triggerJobs();
 433                         $this->restInPeace();
 434                 } catch ( Exception $e ) {
 435                         MWExceptionHandler::handleException( $e );
 436                 }
 437         }
 438
 439         /**
 440          * Checks if the request should abort due to a lagged server,
 441          * for given maxlag parameter.
 442          * @return bool
 443          */
 444         private function checkMaxLag() {
 445                 $maxLag = $this->context->getRequest()->getVal( 'maxlag' );
 446                 if ( !is_null( $maxLag ) ) {
 447                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 448                         if ( $lag > $maxLag ) {
 449                                 $resp = $this->context->getRequest()->response();
 450                                 $resp->header( 'HTTP/1.1 503 Service Unavailable' );
 451                                 $resp->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 452                                 $resp->header( 'X-Database-Lag: ' . intval( $lag ) );
 453                                 $resp->header( 'Content-Type: text/plain' );
 454                                 if ( $this->config->get( 'ShowHostnames' ) ) {
 455                                         echo "Waiting for $host: $lag seconds lagged\n";
 456                                 } else {
 457                                         echo "Waiting for a database server: $lag seconds lagged\n";
 458                                 }
 459
 460
 461                                 exit;
 462                         }
 463                 }
 464                 return true;
 465         }
 466
 467         private function main() {
 468                 global $wgTitle;
 469
 470
 471                 $request = $this->context->getRequest();
 472
 473                 // Send Ajax requests to the Ajax dispatcher.
 474                 if ( $this->config->get( 'UseAjax' ) && $request->getVal( 'action' ) === 'ajax' ) {
 475                         // Set a dummy title, because $wgTitle == null might break things
 476                         $title = Title::makeTitle( NS_MAIN, 'AJAX' );
 477                         $this->context->setTitle( $title );
 478                         $wgTitle = $title;
 479
 480                         $dispatcher = new AjaxDispatcher( $this->config );
 481                         $dispatcher->performAction( $this->context->getUser() );
 482                         return;
 483                 }
 484
 485                 // Get title from request parameters,
 486                 // is set on the fly by parseTitle the first time.
 487                 $title = $this->getTitle();
 488                 $action = $this->getAction();
 489                 $wgTitle = $title;
 490
 491                 // If the user has forceHTTPS set to true, or if the user
 492                 // is in a group requiring HTTPS, or if they have the HTTPS
 493                 // preference set, redirect them to HTTPS.
 494                 // Note: Do this after $wgTitle is setup, otherwise the hooks run from
 495                 // isLoggedIn() will do all sorts of weird stuff.
 496                 if (
 497                         $request->getProtocol() == 'http' &&
 498                         (
 499                                 $request->getCookie( 'forceHTTPS', '' ) ||
 500                                 // check for prefixed version for currently logged in users
 501                                 $request->getCookie( 'forceHTTPS' ) ||
 502                                 // Avoid checking the user and groups unless it's enabled.
 503                                 (
 504                                         $this->context->getUser()->isLoggedIn()
 505                                         && $this->context->getUser()->requiresHTTPS()
 506                                 )
 507                         )
 508                 ) {
 509                         $oldUrl = $request->getFullRequestURL();
 510                         $redirUrl = preg_replace( '#^http://#', 'https://', $oldUrl );
 511
 512                         // ATTENTION: This hook is likely to be removed soon due to overall design of the system.
 513                         if ( Hooks::run( 'BeforeHttpsRedirect', array( $this->context, &$redirUrl ) ) ) {
 514
 515                                 if ( $request->wasPosted() ) {
 516                                         // This is weird and we'd hope it almost never happens. This
 517                                         // means that a POST came in via HTTP and policy requires us
 518                                         // redirecting to HTTPS. It's likely such a request is going
 519                                         // to fail due to post data being lost, but let's try anyway
 520                                         // and just log the instance.
 521                                         //
 522                                         // @todo FIXME: See if we could issue a 307 or 308 here, need
 523                                         // to see how clients (automated & browser) behave when we do
 524                                         wfDebugLog( 'RedirectedPosts', "Redirected from HTTP to HTTPS: $oldUrl" );
 525                                 }
 526                                 // Setup dummy Title, otherwise OutputPage::redirect will fail
 527                                 $title = Title::newFromText( NS_MAIN, 'REDIR' );
 528                                 $this->context->setTitle( $title );
 529                                 $output = $this->context->getOutput();
 530                                 // Since we only do this redir to change proto, always send a vary header
 531                                 $output->addVaryHeader( 'X-Forwarded-Proto' );
 532                                 $output->redirect( $redirUrl );
 533                                 $output->output();
 534                                 return;
 535                         }
 536                 }
 537
 538                 if ( $this->config->get( 'UseFileCache' ) && $title->getNamespace() >= 0 ) {
 539                         if ( HTMLFileCache::useFileCache( $this->context ) ) {
 540                                 // Try low-level file cache hit
 541                                 $cache = new HTMLFileCache( $title, $action );
 542                                 if ( $cache->isCacheGood( /* Assume up to date */ ) ) {
 543                                         // Check incoming headers to see if client has this cached
 544                                         $timestamp = $cache->cacheTimestamp();
 545                                         if ( !$this->context->getOutput()->checkLastModified( $timestamp ) ) {
 546                                                 $cache->loadFromFileCache( $this->context );
 547                                         }
 548                                         // Do any stats increment/watchlist stuff
 549                                         // Assume we're viewing the latest revision (this should always be the case with file cache)
 550                                         $this->context->getWikiPage()->doViewUpdates( $this->context->getUser() );
 551                                         // Tell OutputPage that output is taken care of
 552                                         $this->context->getOutput()->disable();
 553                                         return;
 554                                 }
 555                         }
 556                 }
 557
 558                 // Actually do the work of the request and build up any output
 559                 $this->performRequest();
 560
 561                 // Either all DB and deferred updates should happen or none.
 562                 // The later should not be cancelled due to client disconnect.
 563                 ignore_user_abort( true );
 564                 // Now commit any transactions, so that unreported errors after
 565                 // output() don't roll back the whole DB transaction
 566                 wfGetLBFactory()->commitMasterChanges();
 567
 568                 // Output everything!
 569                 $this->context->getOutput()->output();
 570
 571         }
 572
 573         /**
 574          * Ends this task peacefully
 575          */
 576         public function restInPeace() {
 577                 // Do any deferred jobs
 578                 DeferredUpdates::doUpdates( 'commit' );
 579
 580                 // Log profiling data, e.g. in the database or UDP
 581                 wfLogProfilingData();
 582
 583                 // Commit and close up!
 584                 $factory = wfGetLBFactory();
 585                 $factory->commitMasterChanges();
 586                 $factory->shutdown();
 587
 588                 wfDebug( "Request ended normally\n" );
 589         }
 590
 591         /**
 592          * Potentially open a socket and sent an HTTP request back to the server
 593          * to run a specified number of jobs. This registers a callback to cleanup
 594          * the socket once it's done.
 595          */
 596         protected function triggerJobs() {
 597                 $jobRunRate = $this->config->get( 'JobRunRate' );
 598                 if ( $jobRunRate <= 0 || wfReadOnly() ) {
 599                         return;
 600                 } elseif ( $this->getTitle()->isSpecial( 'RunJobs' ) ) {
 601                         return; // recursion guard
 602                 }
 603
 604
 605                 if ( $jobRunRate < 1 ) {
 606                         $max = mt_getrandmax();
 607                         if ( mt_rand( 0, $max ) > $max * $jobRunRate ) {
 608                                 return; // the higher the job run rate, the less likely we return here
 609                         }
 610                         $n = 1;
 611                 } else {
 612                         $n = intval( $jobRunRate );
 613                 }
 614
 615                 if ( !$this->config->get( 'RunJobsAsync' ) ) {
 616                         // Fall back to running the job here while the user waits
 617                         $runner = new JobRunner();
 618                         $runner->run( array( 'maxJobs'  => $n ) );
 619                         return;
 620                 }
 621
 622                 try {
 623                         if ( !JobQueueGroup::singleton()->queuesHaveJobs( JobQueueGroup::TYPE_DEFAULT ) ) {
 624                                 return; // do not send request if there are probably no jobs
 625                         }
 626                 } catch ( JobQueueError $e ) {
 627                         MWExceptionHandler::logException( $e );
 628                         return; // do not make the site unavailable
 629                 }
 630
 631                 $query = array( 'title' => 'Special:RunJobs',
 632                         'tasks' => 'jobs', 'maxjobs' => $n, 'sigexpiry' => time() + 5 );
 633                 $query['signature'] = SpecialRunJobs::getQuerySignature(
 634                         $query, $this->config->get( 'SecretKey' ) );
 635
 636                 $errno = $errstr = null;
 637                 $info = wfParseUrl( $this->config->get( 'Server' ) );
 638                 wfSuppressWarnings();
 639                 $sock = fsockopen(
 640                         $info['host'],
 641                         isset( $info['port'] ) ? $info['port'] : 80,
 642                         $errno,
 643                         $errstr,
 644                         // If it takes more than 100ms to connect to ourselves there
 645                         // is a problem elsewhere.
 646                         0.1
 647                 );
 648                 wfRestoreWarnings();
 649                 if ( !$sock ) {
 650                         wfDebugLog( 'runJobs', "Failed to start cron API (socket error $errno): $errstr\n" );
 651                         // Fall back to running the job here while the user waits
 652                         $runner = new JobRunner();
 653                         $runner->run( array( 'maxJobs'  => $n ) );
 654                         return;
 655                 }
 656
 657                 $url = wfAppendQuery( wfScript( 'index' ), $query );
 658                 $req = "POST $url HTTP/1.1\r\nHost: {$info['host']}\r\nConnection: Close\r\nContent-Length: 0\r\n\r\n";
 659
 660                 wfDebugLog( 'runJobs', "Running $n job(s) via '$url'\n" );
 661                 // Send a cron API request to be performed in the background.
 662                 // Give up if this takes too long to send (which should be rare).
 663                 stream_set_timeout( $sock, 1 );
 664                 $bytes = fwrite( $sock, $req );
 665                 if ( $bytes !== strlen( $req ) ) {
 666                         wfDebugLog( 'runJobs', "Failed to start cron API (socket write error)\n" );
 667                 } else {
 668                         // Do not wait for the response (the script should handle client aborts).
 669                         // Make sure that we don't close before that script reaches ignore_user_abort().
 670                         $status = fgets( $sock );
 671                         if ( !preg_match( '#^HTTP/\d\.\d 202 #', $status ) ) {
 672                                 wfDebugLog( 'runJobs', "Failed to start cron API: received '$status'\n" );
 673                         }
 674                 }
 675                 fclose( $sock );
 676         }
 677 }