Merge changes Ic13414f0,I26085bfc
[lhc/web/wiklou.git] / 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 * @param $x null|WebRequest
38 * @return WebRequest
39 */
40 public function request( WebRequest $x = null ) {
41 $old = $this->context->getRequest();
42 $this->context->setRequest( $x );
43 return $old;
44 }
45
46 /**
47 * @param $x null|OutputPage
48 * @return OutputPage
49 */
50 public function output( OutputPage $x = null ) {
51 $old = $this->context->getOutput();
52 $this->context->setOutput( $x );
53 return $old;
54 }
55
56 /**
57 * @param IContextSource|null $context
58 */
59 public function __construct( IContextSource $context = null ) {
60 if ( !$context ) {
61 $context = RequestContext::getMain();
62 }
63
64 $this->context = $context;
65 }
66
67 /**
68 * Parse the request to get the Title object
69 *
70 * @return Title object to be $wgTitle
71 */
72 private function parseTitle() {
73 global $wgContLang;
74
75 $request = $this->context->getRequest();
76 $curid = $request->getInt( 'curid' );
77 $title = $request->getVal( 'title' );
78 $action = $request->getVal( 'action', 'view' );
79
80 if ( $request->getCheck( 'search' ) ) {
81 // Compatibility with old search URLs which didn't use Special:Search
82 // Just check for presence here, so blank requests still
83 // show the search page when using ugly URLs (bug 8054).
84 $ret = SpecialPage::getTitleFor( 'Search' );
85 } elseif ( $curid ) {
86 // URLs like this are generated by RC, because rc_title isn't always accurate
87 $ret = Title::newFromID( $curid );
88 } else {
89 $ret = Title::newFromURL( $title );
90 // Alias NS_MEDIA page URLs to NS_FILE...we only use NS_MEDIA
91 // in wikitext links to tell Parser to make a direct file link
92 if ( !is_null( $ret ) && $ret->getNamespace() == NS_MEDIA ) {
93 $ret = Title::makeTitle( NS_FILE, $ret->getDBkey() );
94 }
95 // Check variant links so that interwiki links don't have to worry
96 // about the possible different language variants
97 if ( count( $wgContLang->getVariants() ) > 1
98 && !is_null( $ret ) && $ret->getArticleID() == 0 )
99 {
100 $wgContLang->findVariantLink( $title, $ret );
101 }
102 }
103
104 // If title is not provided, always allow oldid and diff to set the title.
105 // If title is provided, allow oldid and diff to override the title, unless
106 // we are talking about a special page which might use these parameters for
107 // other purposes.
108 if ( $ret === null || !$ret->isSpecialPage() ) {
109 // We can have urls with just ?diff=,?oldid= or even just ?diff=
110 $oldid = $request->getInt( 'oldid' );
111 $oldid = $oldid ? $oldid : $request->getInt( 'diff' );
112 // Allow oldid to override a changed or missing title
113 if ( $oldid ) {
114 $rev = Revision::newFromId( $oldid );
115 $ret = $rev ? $rev->getTitle() : $ret;
116 }
117 }
118
119 // Use the main page as default title if nothing else has been provided
120 if ( $ret === null && strval( $title ) === '' && $action !== 'delete' ) {
121 $ret = Title::newMainPage();
122 }
123
124 if ( $ret === null || ( $ret->getDBkey() == '' && $ret->getInterwiki() == '' ) ) {
125 $ret = SpecialPage::getTitleFor( 'Badtitle' );
126 }
127
128 return $ret;
129 }
130
131 /**
132 * Get the Title object that we'll be acting on, as specified in the WebRequest
133 * @return Title
134 */
135 public function getTitle() {
136 if ( $this->context->getTitle() === null ) {
137 $this->context->setTitle( $this->parseTitle() );
138 }
139 return $this->context->getTitle();
140 }
141
142 /**
143 * Returns the name of the action that will be executed.
144 *
145 * @return string: action
146 */
147 public function getAction() {
148 static $action = null;
149
150 if ( $action === null ) {
151 $action = Action::getActionName( $this->context );
152 }
153
154 return $action;
155 }
156
157 /**
158 * Create an Article object of the appropriate class for the given page.
159 *
160 * @deprecated in 1.18; use Article::newFromTitle() instead
161 * @param $title Title
162 * @param $context IContextSource
163 * @return Article object
164 */
165 public static function articleFromTitle( $title, IContextSource $context ) {
166 wfDeprecated( __METHOD__, '1.18' );
167 return Article::newFromTitle( $title, $context );
168 }
169
170 /**
171 * Performs the request.
172 * - bad titles
173 * - read restriction
174 * - local interwiki redirects
175 * - redirect loop
176 * - special pages
177 * - normal pages
178 *
179 * @throws MWException|PermissionsError|BadTitleError|HttpError
180 * @return void
181 */
182 private function performRequest() {
183 global $wgServer, $wgUsePathInfo, $wgTitle;
184
185 wfProfileIn( __METHOD__ );
186
187 $request = $this->context->getRequest();
188 $requestTitle = $title = $this->context->getTitle();
189 $output = $this->context->getOutput();
190 $user = $this->context->getUser();
191
192 if ( $request->getVal( 'printable' ) === 'yes' ) {
193 $output->setPrintable();
194 }
195
196 $unused = null; // To pass it by reference
197 wfRunHooks( 'BeforeInitialize', array( &$title, &$unused, &$output, &$user, $request, $this ) );
198
199 // Invalid titles. Bug 21776: The interwikis must redirect even if the page name is empty.
200 if ( is_null( $title ) || ( $title->getDBkey() == '' && $title->getInterwiki() == '' ) ||
201 $title->isSpecial( 'Badtitle' ) )
202 {
203 $this->context->setTitle( SpecialPage::getTitleFor( 'Badtitle' ) );
204 wfProfileOut( __METHOD__ );
205 throw new BadTitleError();
206 }
207
208 // Check user's permissions to read this page.
209 // We have to check here to catch special pages etc.
210 // We will check again in Article::view().
211 $permErrors = $title->getUserPermissionsErrors( 'read', $user );
212 if ( count( $permErrors ) ) {
213 // Bug 32276: allowing the skin to generate output with $wgTitle or
214 // $this->context->title set to the input title would allow anonymous users to
215 // determine whether a page exists, potentially leaking private data. In fact, the
216 // curid and oldid request parameters would allow page titles to be enumerated even
217 // when they are not guessable. So we reset the title to Special:Badtitle before the
218 // permissions error is displayed.
219 //
220 // The skin mostly uses $this->context->getTitle() these days, but some extensions
221 // still use $wgTitle.
222
223 $badTitle = SpecialPage::getTitleFor( 'Badtitle' );
224 $this->context->setTitle( $badTitle );
225 $wgTitle = $badTitle;
226
227 wfProfileOut( __METHOD__ );
228 throw new PermissionsError( 'read', $permErrors );
229 }
230
231 $pageView = false; // was an article or special page viewed?
232
233 // Interwiki redirects
234 if ( $title->getInterwiki() != '' ) {
235 $rdfrom = $request->getVal( 'rdfrom' );
236 if ( $rdfrom ) {
237 $url = $title->getFullURL( array( 'rdfrom' => $rdfrom ) );
238 } else {
239 $query = $request->getValues();
240 unset( $query['title'] );
241 $url = $title->getFullURL( $query );
242 }
243 // Check for a redirect loop
244 if ( !preg_match( '/^' . preg_quote( $wgServer, '/' ) . '/', $url )
245 && $title->isLocal() )
246 {
247 // 301 so google et al report the target as the actual url.
248 $output->redirect( $url, 301 );
249 } else {
250 $this->context->setTitle( SpecialPage::getTitleFor( 'Badtitle' ) );
251 wfProfileOut( __METHOD__ );
252 throw new BadTitleError();
253 }
254 // Redirect loops, no title in URL, $wgUsePathInfo URLs, and URLs with a variant
255 } elseif ( $request->getVal( 'action', 'view' ) == 'view' && !$request->wasPosted()
256 && ( $request->getVal( 'title' ) === null ||
257 $title->getPrefixedDBkey() != $request->getVal( 'title' ) )
258 && !count( $request->getValueNames( array( 'action', 'title' ) ) )
259 && wfRunHooks( 'TestCanonicalRedirect', array( $request, $title, $output ) ) )
260 {
261 if ( $title->isSpecialPage() ) {
262 list( $name, $subpage ) = SpecialPageFactory::resolveAlias( $title->getDBkey() );
263 if ( $name ) {
264 $title = SpecialPage::getTitleFor( $name, $subpage );
265 }
266 }
267 $targetUrl = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
268 // Redirect to canonical url, make it a 301 to allow caching
269 if ( $targetUrl == $request->getFullRequestURL() ) {
270 $message = "Redirect loop detected!\n\n" .
271 "This means the wiki got confused about what page was " .
272 "requested; this sometimes happens when moving a wiki " .
273 "to a new server or changing the server configuration.\n\n";
274
275 if ( $wgUsePathInfo ) {
276 $message .= "The wiki is trying to interpret the page " .
277 "title from the URL path portion (PATH_INFO), which " .
278 "sometimes fails depending on the web server. Try " .
279 "setting \"\$wgUsePathInfo = false;\" in your " .
280 "LocalSettings.php, or check that \$wgArticlePath " .
281 "is correct.";
282 } else {
283 $message .= "Your web server was detected as possibly not " .
284 "supporting URL path components (PATH_INFO) correctly; " .
285 "check your LocalSettings.php for a customized " .
286 "\$wgArticlePath setting and/or toggle \$wgUsePathInfo " .
287 "to true.";
288 }
289 throw new HttpError( 500, $message );
290 } else {
291 $output->setSquidMaxage( 1200 );
292 $output->redirect( $targetUrl, '301' );
293 }
294 // Special pages
295 } elseif ( NS_SPECIAL == $title->getNamespace() ) {
296 $pageView = true;
297 // Actions that need to be made when we have a special pages
298 SpecialPageFactory::executePath( $title, $this->context );
299 } else {
300 // ...otherwise treat it as an article view. The article
301 // may be a redirect to another article or URL.
302 $article = $this->initializeArticle();
303 if ( is_object( $article ) ) {
304 $pageView = true;
305 $this->performAction( $article, $requestTitle );
306 } elseif ( is_string( $article ) ) {
307 $output->redirect( $article );
308 } else {
309 wfProfileOut( __METHOD__ );
310 throw new MWException( "Shouldn't happen: MediaWiki::initializeArticle()"
311 . " returned neither an object nor a URL" );
312 }
313 }
314
315 if ( $pageView ) {
316 // Promote user to any groups they meet the criteria for
317 $user->addAutopromoteOnceGroups( 'onView' );
318 }
319
320 wfProfileOut( __METHOD__ );
321 }
322
323 /**
324 * Initialize the main Article object for "standard" actions (view, etc)
325 * Create an Article object for the page, following redirects if needed.
326 *
327 * @return mixed an Article, or a string to redirect to another URL
328 */
329 private function initializeArticle() {
330 global $wgDisableHardRedirects;
331
332 wfProfileIn( __METHOD__ );
333
334 $title = $this->context->getTitle();
335 if ( $this->context->canUseWikiPage() ) {
336 // Try to use request context wiki page, as there
337 // is already data from db saved in per process
338 // cache there from this->getAction() call.
339 $page = $this->context->getWikiPage();
340 $article = Article::newFromWikiPage( $page, $this->context );
341 } else {
342 // This case should not happen, but just in case.
343 $article = Article::newFromTitle( $title, $this->context );
344 $this->context->setWikiPage( $article->getPage() );
345 }
346
347 // NS_MEDIAWIKI has no redirects.
348 // It is also used for CSS/JS, so performance matters here...
349 if ( $title->getNamespace() == NS_MEDIAWIKI ) {
350 wfProfileOut( __METHOD__ );
351 return $article;
352 }
353
354 $request = $this->context->getRequest();
355
356 // Namespace might change when using redirects
357 // Check for redirects ...
358 $action = $request->getVal( 'action', 'view' );
359 $file = ( $title->getNamespace() == NS_FILE ) ? $article->getFile() : null;
360 if ( ( $action == 'view' || $action == 'render' ) // ... for actions that show content
361 && !$request->getVal( 'oldid' ) && // ... and are not old revisions
362 !$request->getVal( 'diff' ) && // ... and not when showing diff
363 $request->getVal( 'redirect' ) != 'no' && // ... unless explicitly told not to
364 // ... and the article is not a non-redirect image page with associated file
365 !( is_object( $file ) && $file->exists() && !$file->getRedirected() ) )
366 {
367 // Give extensions a change to ignore/handle redirects as needed
368 $ignoreRedirect = $target = false;
369
370 wfRunHooks( 'InitializeArticleMaybeRedirect',
371 array( &$title, &$request, &$ignoreRedirect, &$target, &$article ) );
372
373 // Follow redirects only for... redirects.
374 // If $target is set, then a hook wanted to redirect.
375 if ( !$ignoreRedirect && ( $target || $article->isRedirect() ) ) {
376 // Is the target already set by an extension?
377 $target = $target ? $target : $article->followRedirect();
378 if ( is_string( $target ) ) {
379 if ( !$wgDisableHardRedirects ) {
380 // we'll need to redirect
381 wfProfileOut( __METHOD__ );
382 return $target;
383 }
384 }
385 if ( is_object( $target ) ) {
386 // Rewrite environment to redirected article
387 $rarticle = Article::newFromTitle( $target, $this->context );
388 $rarticle->loadPageData();
389 if ( $rarticle->exists() || ( is_object( $file ) && !$file->isLocal() ) ) {
390 $rarticle->setRedirectedFrom( $title );
391 $article = $rarticle;
392 $this->context->setTitle( $target );
393 $this->context->setWikiPage( $article->getPage() );
394 }
395 }
396 } else {
397 $this->context->setTitle( $article->getTitle() );
398 $this->context->setWikiPage( $article->getPage() );
399 }
400 }
401
402 wfProfileOut( __METHOD__ );
403 return $article;
404 }
405
406 /**
407 * Perform one of the "standard" actions
408 *
409 * @param $page Page
410 * @param $requestTitle The original title, before any redirects were applied
411 */
412 private function performAction( Page $page, Title $requestTitle ) {
413 global $wgUseSquid, $wgSquidMaxage;
414
415 wfProfileIn( __METHOD__ );
416
417 $request = $this->context->getRequest();
418 $output = $this->context->getOutput();
419 $title = $this->context->getTitle();
420 $user = $this->context->getUser();
421
422 if ( !wfRunHooks( 'MediaWikiPerformAction',
423 array( $output, $page, $title, $user, $request, $this ) ) )
424 {
425 wfProfileOut( __METHOD__ );
426 return;
427 }
428
429 $act = $this->getAction();
430
431 $action = Action::factory( $act, $page, $this->context );
432
433 if ( $action instanceof Action ) {
434 # Let Squid cache things if we can purge them.
435 if ( $wgUseSquid &&
436 in_array( $request->getFullRequestURL(), $requestTitle->getSquidURLs() )
437 ) {
438 $output->setSquidMaxage( $wgSquidMaxage );
439 }
440
441 $action->show();
442 wfProfileOut( __METHOD__ );
443 return;
444 }
445
446 if ( wfRunHooks( 'UnknownAction', array( $request->getVal( 'action', 'view' ), $page ) ) ) {
447 $output->showErrorPage( 'nosuchaction', 'nosuchactiontext' );
448 }
449
450 wfProfileOut( __METHOD__ );
451 }
452
453 /**
454 * Run the current MediaWiki instance
455 * index.php just calls this
456 */
457 public function run() {
458 try {
459 $this->checkMaxLag();
460 $this->main();
461 $this->restInPeace();
462 } catch ( Exception $e ) {
463 MWExceptionHandler::handle( $e );
464 }
465 }
466
467 /**
468 * Checks if the request should abort due to a lagged server,
469 * for given maxlag parameter.
470 * @return bool
471 */
472 private function checkMaxLag() {
473 global $wgShowHostnames;
474
475 wfProfileIn( __METHOD__ );
476 $maxLag = $this->context->getRequest()->getVal( 'maxlag' );
477 if ( !is_null( $maxLag ) ) {
478 list( $host, $lag ) = wfGetLB()->getMaxLag();
479 if ( $lag > $maxLag ) {
480 $resp = $this->context->getRequest()->response();
481 $resp->header( 'HTTP/1.1 503 Service Unavailable' );
482 $resp->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
483 $resp->header( 'X-Database-Lag: ' . intval( $lag ) );
484 $resp->header( 'Content-Type: text/plain' );
485 if ( $wgShowHostnames ) {
486 echo "Waiting for $host: $lag seconds lagged\n";
487 } else {
488 echo "Waiting for a database server: $lag seconds lagged\n";
489 }
490
491 wfProfileOut( __METHOD__ );
492
493 exit;
494 }
495 }
496 wfProfileOut( __METHOD__ );
497 return true;
498 }
499
500 private function main() {
501 global $wgUseFileCache, $wgTitle, $wgUseAjax;
502
503 wfProfileIn( __METHOD__ );
504
505 $request = $this->context->getRequest();
506
507 // Send Ajax requests to the Ajax dispatcher.
508 if ( $wgUseAjax && $request->getVal( 'action', 'view' ) == 'ajax' ) {
509
510 // Set a dummy title, because $wgTitle == null might break things
511 $title = Title::makeTitle( NS_MAIN, 'AJAX' );
512 $this->context->setTitle( $title );
513 $wgTitle = $title;
514
515 $dispatcher = new AjaxDispatcher();
516 $dispatcher->performAction();
517 wfProfileOut( __METHOD__ );
518 return;
519 }
520
521 // Get title from request parameters,
522 // is set on the fly by parseTitle the first time.
523 $title = $this->getTitle();
524 $action = $this->getAction();
525 $wgTitle = $title;
526
527 // If the user has forceHTTPS set to true, or if the user
528 // is in a group requiring HTTPS, or if they have the HTTPS
529 // preference set, redirect them to HTTPS.
530 // Note: Do this after $wgTitle is setup, otherwise the hooks run from
531 // isLoggedIn() will do all sorts of weird stuff.
532 if (
533 (
534 $request->getCookie( 'forceHTTPS', '' ) ||
535 // check for prefixed version for currently logged in users
536 $request->getCookie( 'forceHTTPS' ) ||
537 // Avoid checking the user and groups unless it's enabled.
538 (
539 $this->context->getUser()->isLoggedIn()
540 && $this->context->getUser()->requiresHTTPS()
541 )
542 ) &&
543 $request->getProtocol() == 'http'
544 ) {
545 $oldUrl = $request->getFullRequestURL();
546 $redirUrl = str_replace( 'http://', 'https://', $oldUrl );
547
548 if ( $request->wasPosted() ) {
549 // This is weird and we'd hope it almost never happens. This
550 // means that a POST came in via HTTP and policy requires us
551 // redirecting to HTTPS. It's likely such a request is going
552 // to fail due to post data being lost, but let's try anyway
553 // and just log the instance.
554 //
555 // @todo @fixme See if we could issue a 307 or 308 here, need
556 // to see how clients (automated & browser) behave when we do
557 wfDebugLog( 'RedirectedPosts', "Redirected from HTTP to HTTPS: $oldUrl" );
558 }
559
560 // Setup dummy Title, otherwise OutputPage::redirect will fail
561 $title = Title::newFromText( NS_MAIN, 'REDIR' );
562 $this->context->setTitle( $title );
563 $output = $this->context->getOutput();
564 // Since we only do this redir to change proto, always send a vary header
565 $output->addVaryHeader( 'X-Forwarded-Proto' );
566 $output->redirect( $redirUrl );
567 $output->output();
568 wfProfileOut( __METHOD__ );
569 return;
570 }
571
572 if ( $wgUseFileCache && $title->getNamespace() >= 0 ) {
573 wfProfileIn( 'main-try-filecache' );
574 if ( HTMLFileCache::useFileCache( $this->context ) ) {
575 // Try low-level file cache hit
576 $cache = HTMLFileCache::newFromTitle( $title, $action );
577 if ( $cache->isCacheGood( /* Assume up to date */ ) ) {
578 // Check incoming headers to see if client has this cached
579 $timestamp = $cache->cacheTimestamp();
580 if ( !$this->context->getOutput()->checkLastModified( $timestamp ) ) {
581 $cache->loadFromFileCache( $this->context );
582 }
583 // Do any stats increment/watchlist stuff
584 // Assume we're viewing the latest revision (this should always be the case with file cache)
585 $this->context->getWikiPage()->doViewUpdates( $this->context->getUser() );
586 // Tell OutputPage that output is taken care of
587 $this->context->getOutput()->disable();
588 wfProfileOut( 'main-try-filecache' );
589 wfProfileOut( __METHOD__ );
590 return;
591 }
592 }
593 wfProfileOut( 'main-try-filecache' );
594 }
595
596 $this->performRequest();
597
598 // Now commit any transactions, so that unreported errors after
599 // output() don't roll back the whole DB transaction
600 wfGetLBFactory()->commitMasterChanges();
601
602 // Output everything!
603 $this->context->getOutput()->output();
604
605 wfProfileOut( __METHOD__ );
606 }
607
608 /**
609 * Ends this task peacefully
610 */
611 public function restInPeace() {
612 // Do any deferred jobs
613 DeferredUpdates::doUpdates( 'commit' );
614
615 // Execute a job from the queue
616 $this->doJobs();
617
618 // Log profiling data, e.g. in the database or UDP
619 wfLogProfilingData();
620
621 // Commit and close up!
622 $factory = wfGetLBFactory();
623 $factory->commitMasterChanges();
624 $factory->shutdown();
625
626 wfDebug( "Request ended normally\n" );
627 }
628
629 /**
630 * Do a job from the job queue
631 */
632 private function doJobs() {
633 global $wgJobRunRate, $wgPhpCli, $IP;
634
635 if ( $wgJobRunRate <= 0 || wfReadOnly() ) {
636 return;
637 }
638
639 if ( $wgJobRunRate < 1 ) {
640 $max = mt_getrandmax();
641 if ( mt_rand( 0, $max ) > $max * $wgJobRunRate ) {
642 return; // the higher $wgJobRunRate, the less likely we return here
643 }
644 $n = 1;
645 } else {
646 $n = intval( $wgJobRunRate );
647 }
648
649 if ( !wfShellExecDisabled() && is_executable( $wgPhpCli ) ) {
650 // Start a background process to run some of the jobs.
651 // This will be asynchronous on *nix though not on Windows.
652 wfProfileIn( __METHOD__ . '-exec' );
653 $retVal = 1;
654 $cmd = wfShellWikiCmd( "$IP/maintenance/runJobs.php", array( '--maxjobs', $n ) );
655 wfShellExec( "$cmd &", $retVal );
656 wfProfileOut( __METHOD__ . '-exec' );
657 } else {
658 try {
659 // Fallback to running the jobs here while the user waits
660 $group = JobQueueGroup::singleton();
661 do {
662 $job = $group->pop( JobQueueGroup::USE_CACHE ); // job from any queue
663 if ( $job ) {
664 $output = $job->toString() . "\n";
665 $t = - microtime( true );
666 wfProfileIn( __METHOD__ . '-' . get_class( $job ) );
667 $success = $job->run();
668 wfProfileOut( __METHOD__ . '-' . get_class( $job ) );
669 $group->ack( $job ); // done
670 $t += microtime( true );
671 $t = round( $t * 1000 );
672 if ( $success === false ) {
673 $output .= "Error: " . $job->getLastError() . ", Time: $t ms\n";
674 } else {
675 $output .= "Success, Time: $t ms\n";
676 }
677 wfDebugLog( 'jobqueue', $output );
678 }
679 } while ( --$n && $job );
680 } catch ( MWException $e ) {
681 // We don't want exceptions thrown during job execution to
682 // be reported to the user since the output is already sent.
683 // Instead we just log them.
684 MWExceptionHandler::logException( $e );
685 }
686 }
687 }
688 }