MediaWiki  1.27.2
MessageCache.php
Go to the documentation of this file.
1 <?php
28 define( 'MSG_CACHE_VERSION', 2 );
29 
35 class MessageCache {
36  const FOR_UPDATE = 1; // force message reload
37 
39  const WAIT_SEC = 15;
41  const LOCK_TTL = 30;
42 
51  protected $mCache;
52 
57  protected $mDisable;
58 
63  protected $mExpiry;
64 
70 
75  protected $mLoadedLanguages = [];
76 
80  protected $mInParser = false;
81 
83  protected $mMemc;
85  protected $wanCache;
86 
92  private static $instance;
93 
100  public static function singleton() {
101  if ( self::$instance === null ) {
103  self::$instance = new self(
107  );
108  }
109 
110  return self::$instance;
111  }
112 
118  public static function destroyInstance() {
119  self::$instance = null;
120  }
121 
128  public static function normalizeKey( $key ) {
130  $lckey = strtr( $key, ' ', '_' );
131  if ( ord( $lckey ) < 128 ) {
132  $lckey[0] = strtolower( $lckey[0] );
133  } else {
134  $lckey = $wgContLang->lcfirst( $lckey );
135  }
136 
137  return $lckey;
138  }
139 
145  function __construct( $memCached, $useDB, $expiry ) {
147 
148  if ( !$memCached ) {
149  $memCached = wfGetCache( CACHE_NONE );
150  }
151 
152  $this->mMemc = $memCached;
153  $this->mDisable = !$useDB;
154  $this->mExpiry = $expiry;
155 
156  if ( $wgUseLocalMessageCache ) {
157  $this->localCache = ObjectCache::getLocalServerInstance( CACHE_NONE );
158  } else {
159  $this->localCache = wfGetCache( CACHE_NONE );
160  }
161 
162  $this->wanCache = ObjectCache::getMainWANInstance();
163  }
164 
170  function getParserOptions() {
171  global $wgUser;
172 
173  if ( !$this->mParserOptions ) {
174  if ( !$wgUser->isSafeToLoad() ) {
175  // $wgUser isn't unstubbable yet, so don't try to get a
176  // ParserOptions for it. And don't cache this ParserOptions
177  // either.
179  $po->setEditSection( false );
180  $po->setAllowUnsafeRawHtml( false );
181  return $po;
182  }
183 
184  $this->mParserOptions = new ParserOptions;
185  $this->mParserOptions->setEditSection( false );
186  // Messages may take parameters that could come
187  // from malicious sources. As a precaution, disable
188  // the <html> parser tag when parsing messages.
189  $this->mParserOptions->setAllowUnsafeRawHtml( false );
190  }
191 
192  return $this->mParserOptions;
193  }
194 
201  protected function getLocalCache( $code ) {
202  $cacheKey = wfMemcKey( __CLASS__, $code );
203 
204  return $this->localCache->get( $cacheKey );
205  }
206 
213  protected function saveToLocalCache( $code, $cache ) {
214  $cacheKey = wfMemcKey( __CLASS__, $code );
215  $this->localCache->set( $cacheKey, $cache );
216  }
217 
239  function load( $code = false, $mode = null ) {
240  if ( !is_string( $code ) ) {
241  # This isn't really nice, so at least make a note about it and try to
242  # fall back
243  wfDebug( __METHOD__ . " called without providing a language code\n" );
244  $code = 'en';
245  }
246 
247  # Don't do double loading...
248  if ( isset( $this->mLoadedLanguages[$code] ) && $mode != self::FOR_UPDATE ) {
249  return true;
250  }
251 
252  # 8 lines of code just to say (once) that message cache is disabled
253  if ( $this->mDisable ) {
254  static $shownDisabled = false;
255  if ( !$shownDisabled ) {
256  wfDebug( __METHOD__ . ": disabled\n" );
257  $shownDisabled = true;
258  }
259 
260  return true;
261  }
262 
263  # Loading code starts
264  $success = false; # Keep track of success
265  $staleCache = false; # a cache array with expired data, or false if none has been loaded
266  $where = []; # Debug info, delayed to avoid spamming debug log too much
267 
268  # Hash of the contents is stored in memcache, to detect if data-center cache
269  # or local cache goes out of date (e.g. due to replace() on some other server)
270  list( $hash, $hashVolatile ) = $this->getValidationHash( $code );
271 
272  # Try the local cache and check against the cluster hash key...
273  $cache = $this->getLocalCache( $code );
274  if ( !$cache ) {
275  $where[] = 'local cache is empty';
276  } elseif ( !isset( $cache['HASH'] ) || $cache['HASH'] !== $hash ) {
277  $where[] = 'local cache has the wrong hash';
278  $staleCache = $cache;
279  } elseif ( $this->isCacheExpired( $cache ) ) {
280  $where[] = 'local cache is expired';
281  $staleCache = $cache;
282  } elseif ( $hashVolatile ) {
283  $where[] = 'local cache validation key is expired/volatile';
284  $staleCache = $cache;
285  } else {
286  $where[] = 'got from local cache';
287  $success = true;
288  $this->mCache[$code] = $cache;
289  }
290 
291  if ( !$success ) {
292  $cacheKey = wfMemcKey( 'messages', $code ); # Key in memc for messages
293  # Try the global cache. If it is empty, try to acquire a lock. If
294  # the lock can't be acquired, wait for the other thread to finish
295  # and then try the global cache a second time.
296  for ( $failedAttempts = 0; $failedAttempts <= 1; $failedAttempts++ ) {
297  if ( $hashVolatile && $staleCache ) {
298  # Do not bother fetching the whole cache blob to avoid I/O.
299  # Instead, just try to get the non-blocking $statusKey lock
300  # below, and use the local stale value if it was not acquired.
301  $where[] = 'global cache is presumed expired';
302  } else {
303  $cache = $this->mMemc->get( $cacheKey );
304  if ( !$cache ) {
305  $where[] = 'global cache is empty';
306  } elseif ( $this->isCacheExpired( $cache ) ) {
307  $where[] = 'global cache is expired';
308  $staleCache = $cache;
309  } elseif ( $hashVolatile ) {
310  # DB results are slave lag prone until the holdoff TTL passes.
311  # By then, updates should be reflected in loadFromDBWithLock().
312  # One thread renerates the cache while others use old values.
313  $where[] = 'global cache is expired/volatile';
314  $staleCache = $cache;
315  } else {
316  $where[] = 'got from global cache';
317  $this->mCache[$code] = $cache;
318  $this->saveToCaches( $cache, 'local-only', $code );
319  $success = true;
320  }
321  }
322 
323  if ( $success ) {
324  # Done, no need to retry
325  break;
326  }
327 
328  # We need to call loadFromDB. Limit the concurrency to one process.
329  # This prevents the site from going down when the cache expires.
330  # Note that the DB slam protection lock here is non-blocking.
331  $loadStatus = $this->loadFromDBWithLock( $code, $where, $mode );
332  if ( $loadStatus === true ) {
333  $success = true;
334  break;
335  } elseif ( $staleCache ) {
336  # Use the stale cache while some other thread constructs the new one
337  $where[] = 'using stale cache';
338  $this->mCache[$code] = $staleCache;
339  $success = true;
340  break;
341  } elseif ( $failedAttempts > 0 ) {
342  # Already blocked once, so avoid another lock/unlock cycle.
343  # This case will typically be hit if memcached is down, or if
344  # loadFromDB() takes longer than LOCK_WAIT.
345  $where[] = "could not acquire status key.";
346  break;
347  } elseif ( $loadStatus === 'cantacquire' ) {
348  # Wait for the other thread to finish, then retry. Normally,
349  # the memcached get() will then yeild the other thread's result.
350  $where[] = 'waited for other thread to complete';
351  $this->getReentrantScopedLock( $cacheKey );
352  } else {
353  # Disable cache; $loadStatus is 'disabled'
354  break;
355  }
356  }
357  }
358 
359  if ( !$success ) {
360  $where[] = 'loading FAILED - cache is disabled';
361  $this->mDisable = true;
362  $this->mCache = false;
363  wfDebugLog( 'MessageCacheError', __METHOD__ . ": Failed to load $code\n" );
364  # This used to throw an exception, but that led to nasty side effects like
365  # the whole wiki being instantly down if the memcached server died
366  } else {
367  # All good, just record the success
368  $this->mLoadedLanguages[$code] = true;
369  }
370 
371  $info = implode( ', ', $where );
372  wfDebugLog( 'MessageCache', __METHOD__ . ": Loading $code... $info\n" );
373 
374  return $success;
375  }
376 
383  protected function loadFromDBWithLock( $code, array &$where, $mode = null ) {
385 
386  # If cache updates on all levels fail, give up on message overrides.
387  # This is to avoid easy site outages; see $saveSuccess comments below.
388  $statusKey = wfMemcKey( 'messages', $code, 'status' );
389  $status = $this->mMemc->get( $statusKey );
390  if ( $status === 'error' ) {
391  $where[] = "could not load; method is still globally disabled";
392  return 'disabled';
393  }
394 
395  # Now let's regenerate
396  $where[] = 'loading from database';
397 
398  # Lock the cache to prevent conflicting writes.
399  # This lock is non-blocking so stale cache can quickly be used.
400  # Note that load() will call a blocking getReentrantScopedLock()
401  # after this if it really need to wait for any current thread.
402  $cacheKey = wfMemcKey( 'messages', $code );
403  $scopedLock = $this->getReentrantScopedLock( $cacheKey, 0 );
404  if ( !$scopedLock ) {
405  $where[] = 'could not acquire main lock';
406  return 'cantacquire';
407  }
408 
409  $cache = $this->loadFromDB( $code, $mode );
410  $this->mCache[$code] = $cache;
411  $saveSuccess = $this->saveToCaches( $cache, 'all', $code );
412 
413  if ( !$saveSuccess ) {
427  if ( !$wgUseLocalMessageCache ) {
428  $this->mMemc->set( $statusKey, 'error', 60 * 5 );
429  $where[] = 'could not save cache, disabled globally for 5 minutes';
430  } else {
431  $where[] = "could not save global cache";
432  }
433  }
434 
435  return true;
436  }
437 
447  function loadFromDB( $code, $mode = null ) {
449 
450  $dbr = wfGetDB( ( $mode == self::FOR_UPDATE ) ? DB_MASTER : DB_SLAVE );
451 
452  $cache = [];
453 
454  # Common conditions
455  $conds = [
456  'page_is_redirect' => 0,
457  'page_namespace' => NS_MEDIAWIKI,
458  ];
459 
460  $mostused = [];
461  if ( $wgAdaptiveMessageCache && $code !== $wgLanguageCode ) {
462  if ( !isset( $this->mCache[$wgLanguageCode] ) ) {
463  $this->load( $wgLanguageCode );
464  }
465  $mostused = array_keys( $this->mCache[$wgLanguageCode] );
466  foreach ( $mostused as $key => $value ) {
467  $mostused[$key] = "$value/$code";
468  }
469  }
470 
471  if ( count( $mostused ) ) {
472  $conds['page_title'] = $mostused;
473  } elseif ( $code !== $wgLanguageCode ) {
474  $conds[] = 'page_title' . $dbr->buildLike( $dbr->anyString(), '/', $code );
475  } else {
476  # Effectively disallows use of '/' character in NS_MEDIAWIKI for uses
477  # other than language code.
478  $conds[] = 'page_title NOT' . $dbr->buildLike( $dbr->anyString(), '/', $dbr->anyString() );
479  }
480 
481  # Conditions to fetch oversized pages to ignore them
482  $bigConds = $conds;
483  $bigConds[] = 'page_len > ' . intval( $wgMaxMsgCacheEntrySize );
484 
485  # Load titles for all oversized pages in the MediaWiki namespace
486  $res = $dbr->select( 'page', 'page_title', $bigConds, __METHOD__ . "($code)-big" );
487  foreach ( $res as $row ) {
488  $cache[$row->page_title] = '!TOO BIG';
489  }
490 
491  # Conditions to load the remaining pages with their contents
492  $smallConds = $conds;
493  $smallConds[] = 'page_latest=rev_id';
494  $smallConds[] = 'rev_text_id=old_id';
495  $smallConds[] = 'page_len <= ' . intval( $wgMaxMsgCacheEntrySize );
496 
497  $res = $dbr->select(
498  [ 'page', 'revision', 'text' ],
499  [ 'page_title', 'old_text', 'old_flags' ],
500  $smallConds,
501  __METHOD__ . "($code)-small"
502  );
503 
504  foreach ( $res as $row ) {
505  $text = Revision::getRevisionText( $row );
506  if ( $text === false ) {
507  // Failed to fetch data; possible ES errors?
508  // Store a marker to fetch on-demand as a workaround...
509  $entry = '!TOO BIG';
510  wfDebugLog(
511  'MessageCache',
512  __METHOD__
513  . ": failed to load message page text for {$row->page_title} ($code)"
514  );
515  } else {
516  $entry = ' ' . $text;
517  }
518  $cache[$row->page_title] = $entry;
519  }
520 
521  $cache['VERSION'] = MSG_CACHE_VERSION;
522  ksort( $cache );
523  $cache['HASH'] = md5( serialize( $cache ) );
524  $cache['EXPIRY'] = wfTimestamp( TS_MW, time() + $this->mExpiry );
525 
526  return $cache;
527  }
528 
535  public function replace( $title, $text ) {
537 
538  if ( $this->mDisable ) {
539  return;
540  }
541 
542  list( $msg, $code ) = $this->figureMessage( $title );
543  if ( strpos( $title, '/' ) !== false && $code === $wgLanguageCode ) {
544  // Content language overrides do not use the /<code> suffix
545  return;
546  }
547 
548  // Note that if the cache is volatile, load() may trigger a DB fetch.
549  // In that case we reenter/reuse the existing cache key lock to avoid
550  // a self-deadlock. This is safe as no reads happen *directly* in this
551  // method between getReentrantScopedLock() and load() below. There is
552  // no risk of data "changing under our feet" for replace().
553  $cacheKey = wfMemcKey( 'messages', $code );
554  $scopedLock = $this->getReentrantScopedLock( $cacheKey );
555  $this->load( $code, self::FOR_UPDATE );
556 
557  $titleKey = wfMemcKey( 'messages', 'individual', $title );
558  if ( $text === false ) {
559  // Article was deleted
560  $this->mCache[$code][$title] = '!NONEXISTENT';
561  $this->wanCache->delete( $titleKey );
562  } elseif ( strlen( $text ) > $wgMaxMsgCacheEntrySize ) {
563  // Check for size
564  $this->mCache[$code][$title] = '!TOO BIG';
565  $this->wanCache->set( $titleKey, ' ' . $text, $this->mExpiry );
566  } else {
567  $this->mCache[$code][$title] = ' ' . $text;
568  $this->wanCache->delete( $titleKey );
569  }
570 
571  // Mark this cache as definitely "latest" (non-volatile) so
572  // load() calls do try to refresh the cache with slave data
573  $this->mCache[$code]['LATEST'] = time();
574 
575  // Update caches if the lock was acquired
576  if ( $scopedLock ) {
577  $this->saveToCaches( $this->mCache[$code], 'all', $code );
578  }
579 
580  ScopedCallback::consume( $scopedLock );
581  // Relay the purge to APC and other DCs
582  $this->wanCache->touchCheckKey( wfMemcKey( 'messages', $code ) );
583 
584  // Also delete cached sidebar... just in case it is affected
585  $codes = [ $code ];
586  if ( $code === 'en' ) {
587  // Delete all sidebars, like for example on action=purge on the
588  // sidebar messages
589  $codes = array_keys( Language::fetchLanguageNames() );
590  }
591 
592  foreach ( $codes as $code ) {
593  $sidebarKey = wfMemcKey( 'sidebar', $code );
594  $this->wanCache->delete( $sidebarKey );
595  }
596 
597  // Update the message in the message blob store
598  $resourceloader = RequestContext::getMain()->getOutput()->getResourceLoader();
599  $blobStore = $resourceloader->getMessageBlobStore();
600  $blobStore->updateMessage( $wgContLang->lcfirst( $msg ) );
601 
602  Hooks::run( 'MessageCacheReplace', [ $title, $text ] );
603  }
604 
611  protected function isCacheExpired( $cache ) {
612  if ( !isset( $cache['VERSION'] ) || !isset( $cache['EXPIRY'] ) ) {
613  return true;
614  }
615  if ( $cache['VERSION'] != MSG_CACHE_VERSION ) {
616  return true;
617  }
618  if ( wfTimestampNow() >= $cache['EXPIRY'] ) {
619  return true;
620  }
621 
622  return false;
623  }
624 
634  protected function saveToCaches( array $cache, $dest, $code = false ) {
635  if ( $dest === 'all' ) {
636  $cacheKey = wfMemcKey( 'messages', $code );
637  $success = $this->mMemc->set( $cacheKey, $cache );
638  } else {
639  $success = true;
640  }
641 
642  $this->setValidationHash( $code, $cache );
643  $this->saveToLocalCache( $code, $cache );
644 
645  return $success;
646  }
647 
654  protected function getValidationHash( $code ) {
655  $curTTL = null;
656  $value = $this->wanCache->get(
657  wfMemcKey( 'messages', $code, 'hash', 'v1' ),
658  $curTTL,
659  [ wfMemcKey( 'messages', $code ) ]
660  );
661 
662  if ( !$value ) {
663  // No hash found at all; cache must regenerate to be safe
664  $hash = false;
665  $expired = true;
666  } else {
667  $hash = $value['hash'];
668  if ( ( time() - $value['latest'] ) < WANObjectCache::HOLDOFF_TTL ) {
669  // Cache was recently updated via replace() and should be up-to-date
670  $expired = false;
671  } else {
672  // See if the "check" key was bumped after the hash was generated
673  $expired = ( $curTTL < 0 );
674  }
675  }
676 
677  return [ $hash, $expired ];
678  }
679 
689  protected function setValidationHash( $code, array $cache ) {
690  $this->wanCache->set(
691  wfMemcKey( 'messages', $code, 'hash', 'v1' ),
692  [
693  'hash' => $cache['HASH'],
694  'latest' => isset( $cache['LATEST'] ) ? $cache['LATEST'] : 0
695  ],
697  );
698  }
699 
705  protected function getReentrantScopedLock( $key, $timeout = self::WAIT_SEC ) {
706  return $this->mMemc->getScopedLock( $key, $timeout, self::LOCK_TTL, __METHOD__ );
707  }
708 
743  function get( $key, $useDB = true, $langcode = true, $isFullKey = false ) {
744  if ( is_int( $key ) ) {
745  // Fix numerical strings that somehow become ints
746  // on their way here
747  $key = (string)$key;
748  } elseif ( !is_string( $key ) ) {
749  throw new MWException( 'Non-string key given' );
750  } elseif ( $key === '' ) {
751  // Shortcut: the empty key is always missing
752  return false;
753  }
754 
755  // For full keys, get the language code from the key
756  $pos = strrpos( $key, '/' );
757  if ( $isFullKey && $pos !== false ) {
758  $langcode = substr( $key, $pos + 1 );
759  $key = substr( $key, 0, $pos );
760  }
761 
762  // Normalise title-case input (with some inlining)
763  $lckey = MessageCache::normalizeKey( $key );
764 
765  Hooks::run( 'MessageCache::get', [ &$lckey ] );
766 
767  // Loop through each language in the fallback list until we find something useful
768  $lang = wfGetLangObj( $langcode );
769  $message = $this->getMessageFromFallbackChain(
770  $lang,
771  $lckey,
772  !$this->mDisable && $useDB
773  );
774 
775  // If we still have no message, maybe the key was in fact a full key so try that
776  if ( $message === false ) {
777  $parts = explode( '/', $lckey );
778  // We may get calls for things that are http-urls from sidebar
779  // Let's not load nonexistent languages for those
780  // They usually have more than one slash.
781  if ( count( $parts ) == 2 && $parts[1] !== '' ) {
782  $message = Language::getMessageFor( $parts[0], $parts[1] );
783  if ( $message === null ) {
784  $message = false;
785  }
786  }
787  }
788 
789  // Post-processing if the message exists
790  if ( $message !== false ) {
791  // Fix whitespace
792  $message = str_replace(
793  [
794  # Fix for trailing whitespace, removed by textarea
795  '&#32;',
796  # Fix for NBSP, converted to space by firefox
797  '&nbsp;',
798  '&#160;',
799  '&shy;'
800  ],
801  [
802  ' ',
803  "\xc2\xa0",
804  "\xc2\xa0",
805  "\xc2\xad"
806  ],
807  $message
808  );
809  }
810 
811  return $message;
812  }
813 
826  protected function getMessageFromFallbackChain( $lang, $lckey, $useDB ) {
828 
829  $alreadyTried = [];
830 
831  // First try the requested language.
832  $message = $this->getMessageForLang( $lang, $lckey, $useDB, $alreadyTried );
833  if ( $message !== false ) {
834  return $message;
835  }
836 
837  // Now try checking the site language.
838  $message = $this->getMessageForLang( $wgContLang, $lckey, $useDB, $alreadyTried );
839  return $message;
840  }
841 
852  private function getMessageForLang( $lang, $lckey, $useDB, &$alreadyTried ) {
854  $langcode = $lang->getCode();
855 
856  // Try checking the database for the requested language
857  if ( $useDB ) {
858  $uckey = $wgContLang->ucfirst( $lckey );
859 
860  if ( !isset( $alreadyTried[ $langcode ] ) ) {
861  $message = $this->getMsgFromNamespace(
862  $this->getMessagePageName( $langcode, $uckey ),
863  $langcode
864  );
865 
866  if ( $message !== false ) {
867  return $message;
868  }
869  $alreadyTried[ $langcode ] = true;
870  }
871  }
872 
873  // Check the CDB cache
874  $message = $lang->getMessage( $lckey );
875  if ( $message !== null ) {
876  return $message;
877  }
878 
879  // Try checking the database for all of the fallback languages
880  if ( $useDB ) {
881  $fallbackChain = Language::getFallbacksFor( $langcode );
882 
883  foreach ( $fallbackChain as $code ) {
884  if ( isset( $alreadyTried[ $code ] ) ) {
885  continue;
886  }
887 
888  $message = $this->getMsgFromNamespace( $this->getMessagePageName( $code, $uckey ), $code );
889 
890  if ( $message !== false ) {
891  return $message;
892  }
893  $alreadyTried[ $code ] = true;
894  }
895  }
896 
897  return false;
898  }
899 
907  private function getMessagePageName( $langcode, $uckey ) {
909  if ( $langcode === $wgLanguageCode ) {
910  // Messages created in the content language will not have the /lang extension
911  return $uckey;
912  } else {
913  return "$uckey/$langcode";
914  }
915  }
916 
929  public function getMsgFromNamespace( $title, $code ) {
930  $this->load( $code );
931  if ( isset( $this->mCache[$code][$title] ) ) {
932  $entry = $this->mCache[$code][$title];
933  if ( substr( $entry, 0, 1 ) === ' ' ) {
934  // The message exists, so make sure a string
935  // is returned.
936  return (string)substr( $entry, 1 );
937  } elseif ( $entry === '!NONEXISTENT' ) {
938  return false;
939  } elseif ( $entry === '!TOO BIG' ) {
940  // Fall through and try invididual message cache below
941  }
942  } else {
943  // XXX: This is not cached in process cache, should it?
944  $message = false;
945  Hooks::run( 'MessagesPreLoad', [ $title, &$message ] );
946  if ( $message !== false ) {
947  return $message;
948  }
949 
950  return false;
951  }
952 
953  # Try the individual message cache
954  $titleKey = wfMemcKey( 'messages', 'individual', $title );
955  $entry = $this->wanCache->get( $titleKey );
956  if ( $entry ) {
957  if ( substr( $entry, 0, 1 ) === ' ' ) {
958  $this->mCache[$code][$title] = $entry;
959 
960  // The message exists, so make sure a string
961  // is returned.
962  return (string)substr( $entry, 1 );
963  } elseif ( $entry === '!NONEXISTENT' ) {
964  $this->mCache[$code][$title] = '!NONEXISTENT';
965 
966  return false;
967  } else {
968  # Corrupt/obsolete entry, delete it
969  $this->wanCache->delete( $titleKey );
970  }
971  }
972 
973  # Try loading it from the database
974  $revision = Revision::newFromTitle( Title::makeTitle( NS_MEDIAWIKI, $title ) );
975  if ( $revision ) {
976  $content = $revision->getContent();
977  if ( !$content ) {
978  // A possibly temporary loading failure.
979  wfDebugLog(
980  'MessageCache',
981  __METHOD__ . ": failed to load message page text for {$title} ($code)"
982  );
983  $message = null; // no negative caching
984  } else {
985  // XXX: Is this the right way to turn a Content object into a message?
986  // NOTE: $content is typically either WikitextContent, JavaScriptContent or
987  // CssContent. MessageContent is *not* used for storing messages, it's
988  // only used for wrapping them when needed.
989  $message = $content->getWikitextForTransclusion();
990 
991  if ( $message === false || $message === null ) {
992  wfDebugLog(
993  'MessageCache',
994  __METHOD__ . ": message content doesn't provide wikitext "
995  . "(content model: " . $content->getModel() . ")"
996  );
997 
998  $message = false; // negative caching
999  } else {
1000  $this->mCache[$code][$title] = ' ' . $message;
1001  $this->wanCache->set( $titleKey, ' ' . $message, $this->mExpiry );
1002  }
1003  }
1004  } else {
1005  $message = false; // negative caching
1006  }
1007 
1008  if ( $message === false ) { // negative caching
1009  $this->mCache[$code][$title] = '!NONEXISTENT';
1010  $this->wanCache->set( $titleKey, '!NONEXISTENT', $this->mExpiry );
1011  }
1012 
1013  return $message;
1014  }
1015 
1023  function transform( $message, $interface = false, $language = null, $title = null ) {
1024  // Avoid creating parser if nothing to transform
1025  if ( strpos( $message, '{{' ) === false ) {
1026  return $message;
1027  }
1028 
1029  if ( $this->mInParser ) {
1030  return $message;
1031  }
1032 
1033  $parser = $this->getParser();
1034  if ( $parser ) {
1035  $popts = $this->getParserOptions();
1036  $popts->setInterfaceMessage( $interface );
1037  $popts->setTargetLanguage( $language );
1038 
1039  $userlang = $popts->setUserLang( $language );
1040  $this->mInParser = true;
1041  $message = $parser->transformMsg( $message, $popts, $title );
1042  $this->mInParser = false;
1043  $popts->setUserLang( $userlang );
1044  }
1045 
1046  return $message;
1047  }
1048 
1052  function getParser() {
1053  global $wgParser, $wgParserConf;
1054  if ( !$this->mParser && isset( $wgParser ) ) {
1055  # Do some initialisation so that we don't have to do it twice
1056  $wgParser->firstCallInit();
1057  # Clone it and store it
1058  $class = $wgParserConf['class'];
1059  if ( $class == 'ParserDiffTest' ) {
1060  # Uncloneable
1061  $this->mParser = new $class( $wgParserConf );
1062  } else {
1063  $this->mParser = clone $wgParser;
1064  }
1065  }
1066 
1067  return $this->mParser;
1068  }
1069 
1078  public function parse( $text, $title = null, $linestart = true,
1079  $interface = false, $language = null
1080  ) {
1081  if ( $this->mInParser ) {
1082  return htmlspecialchars( $text );
1083  }
1084 
1085  $parser = $this->getParser();
1086  $popts = $this->getParserOptions();
1087  $popts->setInterfaceMessage( $interface );
1088 
1089  if ( is_string( $language ) ) {
1090  $language = Language::factory( $language );
1091  }
1092  $popts->setTargetLanguage( $language );
1093 
1094  if ( !$title || !$title instanceof Title ) {
1095  global $wgTitle;
1096  wfDebugLog( 'GlobalTitleFail', __METHOD__ . ' called by ' .
1097  wfGetAllCallers( 5 ) . ' with no title set.' );
1098  $title = $wgTitle;
1099  }
1100  // Sometimes $wgTitle isn't set either...
1101  if ( !$title ) {
1102  # It's not uncommon having a null $wgTitle in scripts. See r80898
1103  # Create a ghost title in such case
1104  $title = Title::makeTitle( NS_SPECIAL, 'Badtitle/title not set in ' . __METHOD__ );
1105  }
1106 
1107  $this->mInParser = true;
1108  $res = $parser->parse( $text, $title, $popts, $linestart );
1109  $this->mInParser = false;
1110 
1111  return $res;
1112  }
1113 
1114  function disable() {
1115  $this->mDisable = true;
1116  }
1117 
1118  function enable() {
1119  $this->mDisable = false;
1120  }
1121 
1134  public function isDisabled() {
1135  return $this->mDisable;
1136  }
1137 
1141  function clear() {
1142  $langs = Language::fetchLanguageNames( null, 'mw' );
1143  foreach ( array_keys( $langs ) as $code ) {
1144  # Global and local caches
1145  $this->wanCache->touchCheckKey( wfMemcKey( 'messages', $code ) );
1146  }
1147 
1148  $this->mLoadedLanguages = [];
1149  }
1150 
1155  public function figureMessage( $key ) {
1157 
1158  $pieces = explode( '/', $key );
1159  if ( count( $pieces ) < 2 ) {
1160  return [ $key, $wgLanguageCode ];
1161  }
1162 
1163  $lang = array_pop( $pieces );
1164  if ( !Language::fetchLanguageName( $lang, null, 'mw' ) ) {
1165  return [ $key, $wgLanguageCode ];
1166  }
1167 
1168  $message = implode( '/', $pieces );
1169 
1170  return [ $message, $lang ];
1171  }
1172 
1181  public function getAllMessageKeys( $code ) {
1183  $this->load( $code );
1184  if ( !isset( $this->mCache[$code] ) ) {
1185  // Apparently load() failed
1186  return null;
1187  }
1188  // Remove administrative keys
1189  $cache = $this->mCache[$code];
1190  unset( $cache['VERSION'] );
1191  unset( $cache['EXPIRY'] );
1192  // Remove any !NONEXISTENT keys
1193  $cache = array_diff( $cache, [ '!NONEXISTENT' ] );
1194 
1195  // Keys may appear with a capital first letter. lcfirst them.
1196  return array_map( [ $wgContLang, 'lcfirst' ], array_keys( $cache ) );
1197  }
1198 }
saveToCaches(array $cache, $dest, $code=false)
Shortcut to update caches.
and how to run hooks for an and one after Each event has a preferably in CamelCase For ArticleDelete hook A clump of code and data that should be run when an event happens This can be either a function and a chunk of data
Definition: hooks.txt:6
static getMainWANInstance()
Get the main WAN cache object.
getMessageFromFallbackChain($lang, $lckey, $useDB)
Given a language, try and fetch messages from that language.
deferred txt A few of the database updates required by various functions here can be deferred until after the result page is displayed to the user For updating the view updating the linked to tables after a etc PHP does not yet have any way to tell the server to actually return and disconnect while still running these but it might have such a feature in the future We handle these by creating a deferred update object and putting those objects on a global list
Definition: deferred.txt:11
wfGetDB($db, $groups=[], $wiki=false)
Get a Database object.
const MSG_CACHE_VERSION
MediaWiki message cache structure version.
the array() calling protocol came about after MediaWiki 1.4rc1.
static getRevisionText($row, $prefix= 'old_', $wiki=false)
Get revision text associated with an old or archive row $row is usually an object from wfFetchRow()...
Definition: Revision.php:1231
I won t presume to tell you how to I m just describing the methods I chose to use for myself If you do choose to follow these it will probably be easier for you to collaborate with others on the but if you want to contribute without by all means do which work well I also use K &R brace matching style I know that s a religious issue for so if you want to use a style that puts opening braces on the next that s OK too
Definition: design.txt:79
magic word the default is to use $key to get the and $key value or $key value text $key value html to format the value $key
Definition: hooks.txt:2321
$success
load($code=false, $mode=null)
Loads messages from caches or from database in this order: (1) local message cache (if $wgUseLocalMes...
isCacheExpired($cache)
Is the given cache array expired due to time passing or a version change?
static getMessageFor($key, $code)
Get a message for a given language.
Definition: Language.php:4384
Set options of the Parser.
$wgParser
Definition: Setup.php:809
globals txt Globals are evil The original MediaWiki code relied on globals for processing context far too often MediaWiki development since then has been a story of slowly moving context out of global variables and into objects Storing processing context in object member variables allows those objects to be reused in a much more flexible way Consider the elegance of
database rows
Definition: globals.txt:10
if(!isset($args[0])) $lang
processing should stop and the error should be shown to the user * false
Definition: hooks.txt:189
static destroyInstance()
Destroy the singleton instance.
null for the local wiki Added in
Definition: hooks.txt:1418
This code would result in ircNotify being run twice when an article is and once for brion Hooks can return three possible true was required This is the default since MediaWiki *some string
Definition: hooks.txt:177
$value
const NS_SPECIAL
Definition: Defines.php:58
Represents a title within MediaWiki.
Definition: Title.php:34
when a variable name is used in a it is silently declared as a new local masking the global
Definition: design.txt:93
static getFallbacksFor($code)
Get the ordered list of fallback languages.
Definition: Language.php:4324
static newFromTitle(LinkTarget $linkTarget, $id=0, $flags=0)
Load either the current, or a specified, revision that's attached to a given link target...
Definition: Revision.php:117
magic word & $parser
Definition: hooks.txt:2321
wfGetMessageCacheStorage()
Get the cache object used by the message cache.
Message cache Performs various MediaWiki namespace-related functions.
transform($message, $interface=false, $language=null, $title=null)
$wgUseLocalMessageCache
Set this to true to maintain a copy of the message cache on the local server.
getMsgFromNamespace($title, $code)
Get a message from the MediaWiki namespace, with caching.
wfDebug($text, $dest= 'all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
static fetchLanguageNames($inLanguage=null, $include= 'mw')
Get an array of language names, indexed by code.
Definition: Language.php:798
getParserOptions()
ParserOptions is lazy initialised.
getLocalCache($code)
Try to load the cache from APC.
you have access to all of the normal MediaWiki so you can get a DB use the cache
Definition: maintenance.txt:52
wfTimestamp($outputtype=TS_UNIX, $ts=0)
Get a timestamp string in one of various formats.
static normalizeKey($key)
Normalize message key input.
$wgLanguageCode
Site language code.
wfDebugLog($logGroup, $text, $dest= 'all', array $context=[])
Send a line to a supplementary debug log file, if configured, or main debug log if not...
saveToLocalCache($code, $cache)
Save the cache to APC.
$wgMaxMsgCacheEntrySize
Maximum entry size in the message cache, in bytes.
static getMain()
Static methods.
wfGetCache($cacheType)
Get a specific cache object.
$wgAdaptiveMessageCache
Instead of caching everything, only cache those messages which have been customised in the site conte...
$res
Definition: database.txt:21
$wgUseDatabaseMessages
Translation using MediaWiki: namespace.
wfTimestampNow()
Convenience function; returns MediaWiki timestamp for the present time.
$cache
Definition: mcc.php:33
$mParserOptions
Message cache has its own parser which it uses to transform messages.
$mLoadedLanguages
Variable for tracking which variables are already loaded.
const DB_SLAVE
Definition: Defines.php:46
namespace and then decline to actually register it file or subcat img or subcat $title
Definition: hooks.txt:912
static $instance
Singleton instance.
getAllMessageKeys($code)
Get all message keys stored in the message cache for a given language.
static run($event, array $args=[], $deprecatedVersion=null)
Call hook functions defined in Hooks::register and $wgHooks.
Definition: Hooks.php:131
getValidationHash($code)
Get the md5 used to validate the local APC cache.
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for and distribution as defined by Sections through of this document Licensor shall mean the copyright owner or entity authorized by the copyright owner that is granting the License Legal Entity shall mean the union of the acting entity and all other entities that control are controlled by or are under common control with that entity For the purposes of this definition control direct or to cause the direction or management of such whether by contract or including but not limited to software source documentation and configuration files Object form shall mean any form resulting from mechanical transformation or translation of a Source including but not limited to compiled object generated and conversions to other media types Work shall mean the work of whether in Source or Object made available under the as indicated by a copyright notice that is included in or attached to the whether in Source or Object that is based or other modifications as a an original work of authorship For the purposes of this Derivative Works shall not include works that remain separable or merely the Work and Derivative Works thereof Contribution shall mean any work of including the original version of the Work and any modifications or additions to that Work or Derivative Works that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner For the purposes of this submitted means any form of or written communication sent to the Licensor or its including but not limited to communication on electronic mailing source code control and issue tracking systems that are managed by
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
Definition: distributors.txt:9
this hook is for auditing only or null if authentication failed before getting that far or null if we can t even determine that probably a stub it is not rendered in wiki pages or galleries in category pages allow injecting custom HTML after the section Any uses of the hook need to handle escaping see BaseTemplate::getToolbox and BaseTemplate::makeListItem for details on the format of individual items inside of this array or by returning and letting standard HTTP rendering take place modifiable or by returning false and taking over the output modifiable & $code
Definition: hooks.txt:762
const NS_MEDIAWIKI
Definition: Defines.php:77
static fetchLanguageName($code, $inLanguage=null, $include= 'all')
Definition: Language.php:886
static newFromAnon()
Get a ParserOptions object for an anonymous user.
__construct($memCached, $useDB, $expiry)
const WAIT_SEC
How long to wait for memcached locks.
const TS_MW
MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
const HOLDOFF_TTL
Seconds to tombstone keys on delete()
wfGetAllCallers($limit=3)
Return a string consisting of callers in the stack.
this hook is for auditing only RecentChangesLinked and Watchlist RecentChangesLinked and Watchlist e g Watchlist removed from all revisions and log entries to which it was applied This gives extensions a chance to take it off their books as the deletion has already been partly carried out by this point or something similar the user will be unable to create the tag set and then return false from the hook function Ensure you consume the ChangeTagAfterDelete hook to carry out custom deletion actions as context called by AbstractContent::getParserOutput May be used to override the normal model specific rendering of page content as context as context the output can only depend on parameters provided to this hook not on global state indicating whether full HTML should be generated If generation of HTML may be but other information should still be present in the ParserOutput object to manipulate or replace but no entry for that model exists in $wgContentHandlers if desired whether it is OK to use $contentModel on $title Handler functions that modify $ok should generally return false to prevent further hooks from further modifying $ok inclusive false for true for descending in case the handler function wants to provide a converted Content object Note that $result getContentModel() must return $toModel. 'CustomEditor'you ll need to handle error messages
Definition: hooks.txt:1099
const FOR_UPDATE
isDisabled()
Whether DB/cache usage is disabled for determining messages.
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:35
$mExpiry
Lifetime for cache, used by object caching.
parse($text, $title=null, $linestart=true, $interface=false, $language=null)
static getLocalServerInstance($fallback=CACHE_NONE)
Factory function for CACHE_ACCEL (referenced from DefaultSettings.php)
this hook is for auditing only RecentChangesLinked and Watchlist RecentChangesLinked and Watchlist e g Watchlist removed from all revisions and log entries to which it was applied This gives extensions a chance to take it off their books as the deletion has already been partly carried out by this point or something similar the user will be unable to create the tag set and then return false from the hook function Ensure you consume the ChangeTagAfterDelete hook to carry out custom deletion actions as context called by AbstractContent::getParserOutput May be used to override the normal model specific rendering of page content $content
Definition: hooks.txt:1004
$wgMsgCacheExpiry
Expiry time for the message cache key.
$mCache
Process local cache of loaded messages that are defined in MediaWiki namespace.
loadFromDBWithLock($code, array &$where, $mode=null)
this class mediates it Skin Encapsulates a look and feel for the wiki All of the functions that render HTML and make choices about how to render it are here and are called from various other places when and is meant to be subclassed with other skins that may override some of its functions The User object contains a reference to a and so rather than having a global skin object we just rely on the global User and get the skin with $wgUser and also has some character encoding functions and other locale stuff The current user interface language is instantiated as and the local content language as $wgContLang
Definition: design.txt:56
getReentrantScopedLock($key, $timeout=self::WAIT_SEC)
this hook is for auditing only RecentChangesLinked and Watchlist RecentChangesLinked and Watchlist e g Watchlist removed from all revisions and log entries to which it was applied This gives extensions a chance to take it off their books as the deletion has already been partly carried out by this point or something similar the user will be unable to create the tag set $status
Definition: hooks.txt:1004
static consume(ScopedCallback &$sc=null)
Trigger a scoped callback and destroy it.
loadFromDB($code, $mode=null)
Loads cacheable messages from the database.
clear()
Clear all stored messages.
setValidationHash($code, array $cache)
Set the md5 used to validate the local disk cache.
wfMemcKey()
Make a cache key for the local wiki.
const DB_MASTER
Definition: Defines.php:47
serialize()
Definition: ApiMessage.php:94
if(!$wgRequest->checkUrlExtension()) if(!$wgEnableAPI) $wgTitle
Definition: api.php:57
$mDisable
Should mean that database cannot be used, but check.
const CACHE_NONE
Definition: Defines.php:102
static factory($code)
Get a cached or new language object for a given language code.
Definition: Language.php:179
getMessageForLang($lang, $lckey, $useDB, &$alreadyTried)
Given a language, try and fetch messages from that language and its fallbacks.
WANObjectCache $wanCache
BagOStuff $mMemc
const LOCK_TTL
How long memcached locks last.
static & makeTitle($ns, $title, $fragment= '', $interwiki= '')
Create a new Title from a namespace index and a DB key.
Definition: Title.php:524
static singleton()
Get the signleton instance of this class.
replace($title, $text)
Updates cache as necessary when message page is changed.
getMessagePageName($langcode, $uckey)
Get the message page name for a given language.
wfGetLangObj($langcode=false)
Return a Language object from $langcode.
$wgUser
Definition: Setup.php:794