3 * Localisation messages cache.
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.
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.
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
25 * MediaWiki message cache structure version.
26 * Bump this whenever the message cache format has changed.
28 define( 'MSG_CACHE_VERSION', 2 );
31 * Memcached timeout when loading a key.
32 * See MessageCache::load()
34 define( 'MSG_LOAD_TIMEOUT', 60 );
38 * Performs various MediaWiki namespace-related functions
42 const FOR_UPDATE
= 1; // force message reload
44 /** How long memcached locks last */
46 /** How long to wait for memcached locks */
50 * Process local cache of loaded messages that are defined in
51 * MediaWiki namespace. First array level is a language code,
52 * second level is message key and the values are either message
53 * content prefixed with space, or !NONEXISTENT for negative
60 * Should mean that database cannot be used, but check
66 * Lifetime for cache, used by object caching.
67 * Set on construction, see __construct().
72 * Message cache has its own parser which it uses to transform
75 protected $mParserOptions, $mParser;
78 * Variable for tracking which variables are already loaded
79 * @var array $mLoadedLanguages
81 protected $mLoadedLanguages = array();
84 * @var bool $mInParser
86 protected $mInParser = false;
90 /** @var WANObjectCache */
96 * @var MessageCache $instance
98 private static $instance;
101 * Get the signleton instance of this class
104 * @return MessageCache
106 public static function singleton() {
107 if ( is_null( self
::$instance ) ) {
108 global $wgUseDatabaseMessages, $wgMsgCacheExpiry;
109 self
::$instance = new self(
110 wfGetMessageCacheStorage(),
111 $wgUseDatabaseMessages,
116 return self
::$instance;
120 * Destroy the singleton instance
124 public static function destroyInstance() {
125 self
::$instance = null;
129 * Normalize message key input
131 * @param string $key Input message key to be normalized
132 * @return string Normalized message key
134 public static function normalizeKey( $key ) {
136 $lckey = strtr( $key, ' ', '_' );
137 if ( ord( $lckey ) < 128 ) {
138 $lckey[0] = strtolower( $lckey[0] );
140 $lckey = $wgContLang->lcfirst( $lckey );
147 * @param BagOStuff $memCached A cache instance. If none, fall back to CACHE_NONE.
149 * @param int $expiry Lifetime for cache. @see $mExpiry.
151 function __construct( $memCached, $useDB, $expiry ) {
152 global $wgUseLocalMessageCache;
155 $memCached = wfGetCache( CACHE_NONE
);
158 $this->mMemc
= $memCached;
159 $this->mDisable
= !$useDB;
160 $this->mExpiry
= $expiry;
162 if ( $wgUseLocalMessageCache ) {
163 $this->localCache
= ObjectCache
::newAccelerator( CACHE_NONE
);
165 $this->localCache
= wfGetCache( CACHE_NONE
);
168 $this->wanCache
= ObjectCache
::getMainWANInstance();
172 * ParserOptions is lazy initialised.
174 * @return ParserOptions
176 function getParserOptions() {
177 if ( !$this->mParserOptions
) {
178 $this->mParserOptions
= new ParserOptions
;
179 $this->mParserOptions
->setEditSection( false );
182 return $this->mParserOptions
;
186 * Try to load the cache from APC.
188 * @param string $code Optional language code, see documenation of load().
189 * @return array|bool The cache array, or false if not in cache.
191 protected function getLocalCache( $code ) {
192 $cacheKey = wfMemcKey( __CLASS__
, $code );
193 return $this->localCache
->get( $cacheKey );
197 * Save the cache to APC.
199 * @param string $code
200 * @param array $cache The cache array
202 protected function saveToLocalCache( $code, $cache ) {
203 $cacheKey = wfMemcKey( __CLASS__
, $code );
204 $this->localCache
->set( $cacheKey, $cache );
208 * Loads messages from caches or from database in this order:
209 * (1) local message cache (if $wgUseLocalMessageCache is enabled)
211 * (3) from the database.
213 * When succesfully loading from (2) or (3), all higher level caches are
214 * updated for the newest version.
216 * Nothing is loaded if member variable mDisable is true, either manually
217 * set by calling code or if message loading fails (is this possible?).
219 * Returns true if cache is already populated or it was succesfully populated,
220 * or false if populating empty cache fails. Also returns true if MessageCache
223 * @param bool|string $code Language to which load messages
224 * @param integer $mode Use MessageCache::FOR_UPDATE to skip process cache
225 * @throws MWException
228 function load( $code = false, $mode = null ) {
229 global $wgUseLocalMessageCache;
231 if ( !is_string( $code ) ) {
232 # This isn't really nice, so at least make a note about it and try to
234 wfDebug( __METHOD__
. " called without providing a language code\n" );
238 # Don't do double loading...
239 if ( isset( $this->mLoadedLanguages
[$code] ) && $mode != self
::FOR_UPDATE
) {
243 # 8 lines of code just to say (once) that message cache is disabled
244 if ( $this->mDisable
) {
245 static $shownDisabled = false;
246 if ( !$shownDisabled ) {
247 wfDebug( __METHOD__
. ": disabled\n" );
248 $shownDisabled = true;
254 # Loading code starts
255 $success = false; # Keep track of success
256 $staleCache = false; # a cache array with expired data, or false if none has been loaded
257 $where = array(); # Debug info, delayed to avoid spamming debug log too much
259 # Hash of the contents is stored in memcache, to detect if data-center cache
260 # or local cache goes out of date (e.g. due to replace() on some other server)
261 list( $hash, $hashVolatile ) = $this->getValidationHash( $code );
263 if ( $wgUseLocalMessageCache && $hash ) {
264 # Try the local cache and check against the cluster hash key...
265 $cache = $this->getLocalCache( $code );
267 $where[] = 'local cache is empty';
268 } elseif ( !isset( $cache['HASH'] ) ||
$cache['HASH'] !== $hash ) {
269 $where[] = 'local cache has the wrong hash';
270 $staleCache = $cache;
271 } elseif ( $this->isCacheExpired( $cache ) ) {
272 $where[] = 'local cache is expired';
273 $staleCache = $cache;
274 } elseif ( $hashVolatile ) {
275 $where[] = 'local cache validation key is expired/volatile';
276 $staleCache = $cache;
278 $where[] = 'got from local cache';
280 $this->mCache
[$code] = $cache;
285 $cacheKey = wfMemcKey( 'messages', $code ); # Key in memc for messages
286 # Try the global cache. If it is empty, try to acquire a lock. If
287 # the lock can't be acquired, wait for the other thread to finish
288 # and then try the global cache a second time.
289 for ( $failedAttempts = 0; $failedAttempts < 2; $failedAttempts++
) {
290 if ( $hashVolatile && $staleCache ) {
291 # Do not bother fetching the whole cache blob to avoid I/O.
292 # Instead, just try to get the non-blocking $statusKey lock
293 # below, and use the local stale value if it was not acquired.
294 $where[] = 'global cache is presumed expired';
296 $cache = $this->mMemc
->get( $cacheKey );
298 $where[] = 'global cache is empty';
299 } elseif ( $this->isCacheExpired( $cache ) ) {
300 $where[] = 'global cache is expired';
301 $staleCache = $cache;
302 } elseif ( $hashVolatile ) {
303 # DB results are slave lag prone until the holdoff TTL passes.
304 # By then, updates should be reflected in loadFromDBWithLock().
305 # One thread renerates the cache while others use old values.
306 $where[] = 'global cache is expired/volatile';
307 $staleCache = $cache;
309 $where[] = 'got from global cache';
310 $this->mCache
[$code] = $cache;
311 $this->saveToCaches( $cache, 'local-only', $code );
317 # Done, no need to retry
321 # We need to call loadFromDB. Limit the concurrency to one process.
322 # This prevents the site from going down when the cache expires.
323 # Note that the slam-protection lock here is non-blocking.
324 if ( $this->loadFromDBWithLock( $code, $where ) ) {
327 } elseif ( $staleCache ) {
328 # Use the stale cache while some other thread constructs the new one
329 $where[] = 'using stale cache';
330 $this->mCache
[$code] = $staleCache;
333 } elseif ( $failedAttempts > 0 ) {
334 # Already retried once, still failed, so don't do another lock/unlock cycle
335 # This case will typically be hit if memcached is down, or if
336 # loadFromDB() takes longer than MSG_WAIT_TIMEOUT
337 $where[] = "could not acquire status key.";
340 $statusKey = wfMemcKey( 'messages', $code, 'status' );
341 $status = $this->mMemc
->get( $statusKey );
342 if ( $status === 'error' ) {
346 # Wait for the other thread to finish, then retry. Normally,
347 # the memcached get() will then yeild the other thread's result.
348 $where[] = 'waited for other thread to complete';
349 $this->getReentrantScopedLock( $cacheKey );
356 $where[] = 'loading FAILED - cache is disabled';
357 $this->mDisable
= true;
358 $this->mCache
= false;
359 # This used to throw an exception, but that led to nasty side effects like
360 # the whole wiki being instantly down if the memcached server died
362 # All good, just record the success
363 $this->mLoadedLanguages
[$code] = true;
366 $info = implode( ', ', $where );
367 wfDebugLog( 'MessageCache', __METHOD__
. ": Loading $code... $info\n" );
373 * @param string $code
374 * @param array $where List of wfDebug() comments
375 * @return bool Lock acquired and loadFromDB() called
377 protected function loadFromDBWithLock( $code, array &$where ) {
378 global $wgUseLocalMessageCache;
380 $memCache = $this->mMemc
;
382 # Get the non-blocking status key lock. This lets the caller quickly know
383 # to use any stale cache lying around. Otherwise, it may do a blocking
384 # lock to try to obtain the messages.
385 $statusKey = wfMemcKey( 'messages', $code, 'status' );
386 if ( !$memCache->add( $statusKey, 'loading', MSG_LOAD_TIMEOUT
) ) {
387 return false; // could not acquire lock
390 # Unlock the status key if there is an exception
391 $statusUnlocker = new ScopedCallback( function () use ( $memCache, $statusKey ) {
392 $memCache->delete( $statusKey );
395 # Now let's regenerate
396 $where[] = 'loading from database';
398 $cacheKey = wfMemcKey( 'messages', $code );
399 # Lock the cache to prevent conflicting writes
400 # If this lock fails, it doesn't really matter, it just means the
401 # write is potentially non-atomic, e.g. the results of a replace()
403 $mainUnlocker = $this->getReentrantScopedLock( $cacheKey );
404 if ( !$mainUnlocker ) {
405 $where[] = 'could not acquire main lock';
408 $cache = $this->loadFromDB( $code );
409 $this->mCache
[$code] = $cache;
410 $saveSuccess = $this->saveToCaches( $cache, 'all', $code );
413 ScopedCallback
::consume( $mainUnlocker );
414 ScopedCallback
::consume( $statusUnlocker );
416 if ( !$saveSuccess ) {
417 # Cache save has failed.
418 # There are two main scenarios where this could be a problem:
420 # - The cache is more than the maximum size (typically
423 # - Memcached has no space remaining in the relevant slab
424 # class. This is unlikely with recent versions of
427 # Either way, if there is a local cache, nothing bad will
428 # happen. If there is no local cache, disabling the message
429 # cache for all requests avoids incurring a loadFromDB()
430 # overhead on every request, and thus saves the wiki from
431 # complete downtime under moderate traffic conditions.
432 if ( !$wgUseLocalMessageCache ) {
433 $memCache->set( $statusKey, 'error', 60 * 5 );
434 $where[] = 'could not save cache, disabled globally for 5 minutes';
436 $where[] = "could not save global cache";
444 * Loads cacheable messages from the database. Messages bigger than
445 * $wgMaxMsgCacheEntrySize are assigned a special value, and are loaded
446 * on-demand from the database later.
448 * @param string $code Language code.
449 * @return array Loaded messages for storing in caches.
451 function loadFromDB( $code ) {
452 global $wgMaxMsgCacheEntrySize, $wgLanguageCode, $wgAdaptiveMessageCache;
454 $dbr = wfGetDB( DB_SLAVE
);
459 'page_is_redirect' => 0,
460 'page_namespace' => NS_MEDIAWIKI
,
464 if ( $wgAdaptiveMessageCache && $code !== $wgLanguageCode ) {
465 if ( !isset( $this->mCache
[$wgLanguageCode] ) ) {
466 $this->load( $wgLanguageCode );
468 $mostused = array_keys( $this->mCache
[$wgLanguageCode] );
469 foreach ( $mostused as $key => $value ) {
470 $mostused[$key] = "$value/$code";
474 if ( count( $mostused ) ) {
475 $conds['page_title'] = $mostused;
476 } elseif ( $code !== $wgLanguageCode ) {
477 $conds[] = 'page_title' . $dbr->buildLike( $dbr->anyString(), '/', $code );
479 # Effectively disallows use of '/' character in NS_MEDIAWIKI for uses
480 # other than language code.
481 $conds[] = 'page_title NOT' . $dbr->buildLike( $dbr->anyString(), '/', $dbr->anyString() );
484 # Conditions to fetch oversized pages to ignore them
486 $bigConds[] = 'page_len > ' . intval( $wgMaxMsgCacheEntrySize );
488 # Load titles for all oversized pages in the MediaWiki namespace
489 $res = $dbr->select( 'page', 'page_title', $bigConds, __METHOD__
. "($code)-big" );
490 foreach ( $res as $row ) {
491 $cache[$row->page_title
] = '!TOO BIG';
494 # Conditions to load the remaining pages with their contents
495 $smallConds = $conds;
496 $smallConds[] = 'page_latest=rev_id';
497 $smallConds[] = 'rev_text_id=old_id';
498 $smallConds[] = 'page_len <= ' . intval( $wgMaxMsgCacheEntrySize );
501 array( 'page', 'revision', 'text' ),
502 array( 'page_title', 'old_text', 'old_flags' ),
504 __METHOD__
. "($code)-small"
507 foreach ( $res as $row ) {
508 $text = Revision
::getRevisionText( $row );
509 if ( $text === false ) {
510 // Failed to fetch data; possible ES errors?
511 // Store a marker to fetch on-demand as a workaround...
516 . ": failed to load message page text for {$row->page_title} ($code)"
519 $entry = ' ' . $text;
521 $cache[$row->page_title
] = $entry;
524 $cache['VERSION'] = MSG_CACHE_VERSION
;
526 $cache['HASH'] = md5( serialize( $cache ) );
527 $cache['EXPIRY'] = wfTimestamp( TS_MW
, time() +
$this->mExpiry
);
533 * Updates cache as necessary when message page is changed
535 * @param string $title Name of the page changed.
536 * @param mixed $text New contents of the page.
538 public function replace( $title, $text ) {
539 global $wgMaxMsgCacheEntrySize, $wgContLang, $wgLanguageCode;
541 if ( $this->mDisable
) {
545 list( $msg, $code ) = $this->figureMessage( $title );
546 if ( strpos( $title, '/' ) !== false && $code === $wgLanguageCode ) {
547 # Content language overrides do not use the /<code> suffix
551 # Note that if the cache is volatile, load() may trigger a DB fetch.
552 # In that case we reenter/reuse the existing cache key lock to avoid
553 # a self-deadlock. This is safe as no reads happen *directly* in this
554 # method between getReentrantScopedLock() and load() below. There is
555 # no risk of data "changing under our feet" for replace().
556 $cacheKey = wfMemcKey( 'messages', $code );
557 $scopedLock = $this->getReentrantScopedLock( $cacheKey );
558 $this->load( $code, self
::FOR_UPDATE
);
560 $titleKey = wfMemcKey( 'messages', 'individual', $title );
562 if ( $text === false ) {
563 # Article was deleted
564 $this->mCache
[$code][$title] = '!NONEXISTENT';
565 $this->mMemc
->delete( $titleKey );
566 } elseif ( strlen( $text ) > $wgMaxMsgCacheEntrySize ) {
568 $this->mCache
[$code][$title] = '!TOO BIG';
569 $this->mMemc
->set( $titleKey, ' ' . $text, $this->mExpiry
);
571 $this->mCache
[$code][$title] = ' ' . $text;
572 $this->mMemc
->delete( $titleKey );
576 $this->saveToCaches( $this->mCache
[$code], 'all', $code );
577 ScopedCallback
::consume( $scopedLock );
578 $this->wanCache
->touchCheckKey( wfMemcKey( 'messages', $code ) );
580 // Also delete cached sidebar... just in case it is affected
581 $codes = array( $code );
582 if ( $code === 'en' ) {
583 // Delete all sidebars, like for example on action=purge on the
585 $codes = array_keys( Language
::fetchLanguageNames() );
588 foreach ( $codes as $code ) {
589 $sidebarKey = wfMemcKey( 'sidebar', $code );
590 $this->wanCache
->delete( $sidebarKey, 5 );
593 // Update the message in the message blob store
594 $blobStore = new MessageBlobStore();
595 $blobStore->updateMessage( $wgContLang->lcfirst( $msg ) );
597 Hooks
::run( 'MessageCacheReplace', array( $title, $text ) );
601 * Is the given cache array expired due to time passing or a version change?
603 * @param array $cache
606 protected function isCacheExpired( $cache ) {
607 if ( !isset( $cache['VERSION'] ) ||
!isset( $cache['EXPIRY'] ) ) {
610 if ( $cache['VERSION'] != MSG_CACHE_VERSION
) {
613 if ( wfTimestampNow() >= $cache['EXPIRY'] ) {
621 * Shortcut to update caches.
623 * @param array $cache Cached messages with a version.
624 * @param string $dest Either "local-only" to save to local caches only
625 * or "all" to save to all caches.
626 * @param string|bool $code Language code (default: false)
629 protected function saveToCaches( $cache, $dest, $code = false ) {
630 global $wgUseLocalMessageCache;
632 if ( $dest === 'all' ) {
633 $cacheKey = wfMemcKey( 'messages', $code );
634 $success = $this->mMemc
->set( $cacheKey, $cache );
639 $this->setValidationHash( $code, $cache['HASH'] );
641 # Save to local cache
642 if ( $wgUseLocalMessageCache ) {
643 $this->saveToLocalCache( $code, $cache );
650 * Get the md5 used to validate the local disk cache
652 * @param string $code
653 * @return array (hash or false, bool expiry/volatility status)
655 protected function getValidationHash( $code ) {
657 $value = $this->wanCache
->get(
658 wfMemcKey( 'messages', $code, 'hash' ),
660 array( wfMemcKey( 'messages', $code ) )
662 $expired = ( $curTTL === null ||
$curTTL < 0 );
664 return array( $value, $expired );
668 * Set the md5 used to validate the local disk cache
670 * @param string $code
671 * @param string $hash
673 protected function setValidationHash( $code, $hash ) {
674 $this->wanCache
->set(
675 wfMemcKey( 'messages', $code, 'hash' ),
677 WANObjectCache
::TTL_NONE
682 * @param string $key A language message cache key that stores blobs
683 * @return null|ScopedCallback
685 protected function getReentrantScopedLock( $key ) {
686 return $this->mMemc
->getScopedLock( $key, self
::WAIT_SEC
, self
::LOCK_TTL
, __METHOD__
);
690 * Get a message from either the content language or the user language.
692 * First, assemble a list of languages to attempt getting the message from. This
693 * chain begins with the requested language and its fallbacks and then continues with
694 * the content language and its fallbacks. For each language in the chain, the following
695 * process will occur (in this order):
696 * 1. If a language-specific override, i.e., [[MW:msg/lang]], is available, use that.
697 * Note: for the content language, there is no /lang subpage.
698 * 2. Fetch from the static CDB cache.
699 * 3. If available, check the database for fallback language overrides.
701 * This process provides a number of guarantees. When changing this code, make sure all
702 * of these guarantees are preserved.
703 * * If the requested language is *not* the content language, then the CDB cache for that
704 * specific language will take precedence over the root database page ([[MW:msg]]).
705 * * Fallbacks will be just that: fallbacks. A fallback language will never be reached if
706 * the message is available *anywhere* in the language for which it is a fallback.
708 * @param string $key The message key
709 * @param bool $useDB If true, look for the message in the DB, false
710 * to use only the compiled l10n cache.
711 * @param bool|string|object $langcode Code of the language to get the message for.
712 * - If string and a valid code, will create a standard language object
713 * - If string but not a valid code, will create a basic language object
714 * - If boolean and false, create object from the current users language
715 * - If boolean and true, create object from the wikis content language
716 * - If language object, use it as given
717 * @param bool $isFullKey Specifies whether $key is a two part key "msg/lang".
719 * @throws MWException When given an invalid key
720 * @return string|bool False if the message doesn't exist, otherwise the
721 * message (which can be empty)
723 function get( $key, $useDB = true, $langcode = true, $isFullKey = false ) {
726 if ( is_int( $key ) ) {
727 // Fix numerical strings that somehow become ints
730 } elseif ( !is_string( $key ) ) {
731 throw new MWException( 'Non-string key given' );
732 } elseif ( $key === '' ) {
733 // Shortcut: the empty key is always missing
737 // For full keys, get the language code from the key
738 $pos = strrpos( $key, '/' );
739 if ( $isFullKey && $pos !== false ) {
740 $langcode = substr( $key, $pos +
1 );
741 $key = substr( $key, 0, $pos );
744 // Normalise title-case input (with some inlining)
745 $lckey = MessageCache
::normalizeKey( $key );
747 Hooks
::run( 'MessageCache::get', array( &$lckey ) );
749 if ( ord( $lckey ) < 128 ) {
750 $uckey = ucfirst( $lckey );
752 $uckey = $wgContLang->ucfirst( $lckey );
755 // Loop through each language in the fallback list until we find something useful
756 $lang = wfGetLangObj( $langcode );
757 $message = $this->getMessageFromFallbackChain(
761 !$this->mDisable
&& $useDB
764 // If we still have no message, maybe the key was in fact a full key so try that
765 if ( $message === false ) {
766 $parts = explode( '/', $lckey );
767 // We may get calls for things that are http-urls from sidebar
768 // Let's not load nonexistent languages for those
769 // They usually have more than one slash.
770 if ( count( $parts ) == 2 && $parts[1] !== '' ) {
771 $message = Language
::getMessageFor( $parts[0], $parts[1] );
772 if ( $message === null ) {
778 // Post-processing if the message exists
779 if ( $message !== false ) {
781 $message = str_replace(
783 # Fix for trailing whitespace, removed by textarea
785 # Fix for NBSP, converted to space by firefox
802 * Given a language, try and fetch a message from that language, then the
803 * fallbacks of that language, then the site language, then the fallbacks for the
806 * @param Language $lang Requested language
807 * @param string $lckey Lowercase key for the message
808 * @param string $uckey Uppercase key for the message
809 * @param bool $useDB Whether to use the database
811 * @see MessageCache::get
812 * @return string|bool The message, or false if not found
814 protected function getMessageFromFallbackChain( $lang, $lckey, $uckey, $useDB ) {
815 global $wgLanguageCode, $wgContLang;
817 $langcode = $lang->getCode();
820 // First try the requested language.
822 if ( $langcode === $wgLanguageCode ) {
823 // Messages created in the content language will not have the /lang extension
824 $message = $this->getMsgFromNamespace( $uckey, $langcode );
826 $message = $this->getMsgFromNamespace( "$uckey/$langcode", $langcode );
830 if ( $message !== false ) {
834 // Check the CDB cache
835 $message = $lang->getMessage( $lckey );
836 if ( $message !== null ) {
840 list( $fallbackChain, $siteFallbackChain ) =
841 Language
::getFallbacksIncludingSiteLanguage( $langcode );
843 // Next try checking the database for all of the fallback languages of the requested language.
845 foreach ( $fallbackChain as $code ) {
846 if ( $code === $wgLanguageCode ) {
847 // Messages created in the content language will not have the /lang extension
848 $message = $this->getMsgFromNamespace( $uckey, $code );
850 $message = $this->getMsgFromNamespace( "$uckey/$code", $code );
853 if ( $message !== false ) {
854 // Found the message.
860 // Now try checking the site language.
862 $message = $this->getMsgFromNamespace( $uckey, $wgLanguageCode );
863 if ( $message !== false ) {
868 $message = $wgContLang->getMessage( $lckey );
869 if ( $message !== null ) {
873 // Finally try the DB for the site language's fallbacks.
875 foreach ( $siteFallbackChain as $code ) {
876 $message = $this->getMsgFromNamespace( "$uckey/$code", $code );
877 if ( $message === false && $code === $wgLanguageCode ) {
878 // Messages created in the content language will not have the /lang extension
879 $message = $this->getMsgFromNamespace( $uckey, $code );
882 if ( $message !== false ) {
883 // Found the message.
893 * Get a message from the MediaWiki namespace, with caching. The key must
894 * first be converted to two-part lang/msg form if necessary.
896 * Unlike self::get(), this function doesn't resolve fallback chains, and
897 * some callers require this behavior. LanguageConverter::parseCachedTable()
898 * and self::get() are some examples in core.
900 * @param string $title Message cache key with initial uppercase letter.
901 * @param string $code Code denoting the language to try.
902 * @return string|bool The message, or false if it does not exist or on error
904 function getMsgFromNamespace( $title, $code ) {
905 $this->load( $code );
906 if ( isset( $this->mCache
[$code][$title] ) ) {
907 $entry = $this->mCache
[$code][$title];
908 if ( substr( $entry, 0, 1 ) === ' ' ) {
909 // The message exists, so make sure a string
911 return (string)substr( $entry, 1 );
912 } elseif ( $entry === '!NONEXISTENT' ) {
914 } elseif ( $entry === '!TOO BIG' ) {
915 // Fall through and try invididual message cache below
918 // XXX: This is not cached in process cache, should it?
920 Hooks
::run( 'MessagesPreLoad', array( $title, &$message ) );
921 if ( $message !== false ) {
928 # Try the individual message cache
929 $titleKey = wfMemcKey( 'messages', 'individual', $title );
930 $entry = $this->mMemc
->get( $titleKey );
932 if ( substr( $entry, 0, 1 ) === ' ' ) {
933 $this->mCache
[$code][$title] = $entry;
935 // The message exists, so make sure a string
937 return (string)substr( $entry, 1 );
938 } elseif ( $entry === '!NONEXISTENT' ) {
939 $this->mCache
[$code][$title] = '!NONEXISTENT';
943 # Corrupt/obsolete entry, delete it
944 $this->mMemc
->delete( $titleKey );
948 # Try loading it from the database
949 $revision = Revision
::newFromTitle(
950 Title
::makeTitle( NS_MEDIAWIKI
, $title ), false, Revision
::READ_LATEST
953 $content = $revision->getContent();
955 // A possibly temporary loading failure.
958 __METHOD__
. ": failed to load message page text for {$title} ($code)"
960 $message = null; // no negative caching
962 // XXX: Is this the right way to turn a Content object into a message?
963 // NOTE: $content is typically either WikitextContent, JavaScriptContent or
964 // CssContent. MessageContent is *not* used for storing messages, it's
965 // only used for wrapping them when needed.
966 $message = $content->getWikitextForTransclusion();
968 if ( $message === false ||
$message === null ) {
971 __METHOD__
. ": message content doesn't provide wikitext "
972 . "(content model: " . $content->getContentHandler() . ")"
975 $message = false; // negative caching
977 $this->mCache
[$code][$title] = ' ' . $message;
978 $this->mMemc
->set( $titleKey, ' ' . $message, $this->mExpiry
);
982 $message = false; // negative caching
985 if ( $message === false ) { // negative caching
986 $this->mCache
[$code][$title] = '!NONEXISTENT';
987 $this->mMemc
->set( $titleKey, '!NONEXISTENT', $this->mExpiry
);
994 * @param string $message
995 * @param bool $interface
996 * @param string $language Language code
997 * @param Title $title
1000 function transform( $message, $interface = false, $language = null, $title = null ) {
1001 // Avoid creating parser if nothing to transform
1002 if ( strpos( $message, '{{' ) === false ) {
1006 if ( $this->mInParser
) {
1010 $parser = $this->getParser();
1012 $popts = $this->getParserOptions();
1013 $popts->setInterfaceMessage( $interface );
1014 $popts->setTargetLanguage( $language );
1016 $userlang = $popts->setUserLang( $language );
1017 $this->mInParser
= true;
1018 $message = $parser->transformMsg( $message, $popts, $title );
1019 $this->mInParser
= false;
1020 $popts->setUserLang( $userlang );
1029 function getParser() {
1030 global $wgParser, $wgParserConf;
1031 if ( !$this->mParser
&& isset( $wgParser ) ) {
1032 # Do some initialisation so that we don't have to do it twice
1033 $wgParser->firstCallInit();
1034 # Clone it and store it
1035 $class = $wgParserConf['class'];
1036 if ( $class == 'ParserDiffTest' ) {
1038 $this->mParser
= new $class( $wgParserConf );
1040 $this->mParser
= clone $wgParser;
1044 return $this->mParser
;
1048 * @param string $text
1049 * @param Title $title
1050 * @param bool $linestart Whether or not this is at the start of a line
1051 * @param bool $interface Whether this is an interface message
1052 * @param string $language Language code
1053 * @return ParserOutput|string
1055 public function parse( $text, $title = null, $linestart = true,
1056 $interface = false, $language = null
1058 if ( $this->mInParser
) {
1059 return htmlspecialchars( $text );
1062 $parser = $this->getParser();
1063 $popts = $this->getParserOptions();
1064 $popts->setInterfaceMessage( $interface );
1065 $popts->setTargetLanguage( $language );
1067 if ( !$title ||
!$title instanceof Title
) {
1069 wfDebugLog( 'GlobalTitleFail', __METHOD__
. ' called by ' .
1070 wfGetAllCallers( 5 ) . ' with no title set.' );
1073 // Sometimes $wgTitle isn't set either...
1075 # It's not uncommon having a null $wgTitle in scripts. See r80898
1076 # Create a ghost title in such case
1077 $title = Title
::makeTitle( NS_SPECIAL
, 'Badtitle/title not set in ' . __METHOD__
);
1080 $this->mInParser
= true;
1081 $res = $parser->parse( $text, $title, $popts, $linestart );
1082 $this->mInParser
= false;
1087 function disable() {
1088 $this->mDisable
= true;
1092 $this->mDisable
= false;
1096 * Clear all stored messages. Mainly used after a mass rebuild.
1099 $langs = Language
::fetchLanguageNames( null, 'mw' );
1100 foreach ( array_keys( $langs ) as $code ) {
1101 # Global and local caches
1102 $this->wanCache
->touchCheckKey( wfMemcKey( 'messages', $code ) );
1105 $this->mLoadedLanguages
= array();
1109 * @param string $key
1112 public function figureMessage( $key ) {
1113 global $wgLanguageCode;
1115 $pieces = explode( '/', $key );
1116 if ( count( $pieces ) < 2 ) {
1117 return array( $key, $wgLanguageCode );
1120 $lang = array_pop( $pieces );
1121 if ( !Language
::fetchLanguageName( $lang, null, 'mw' ) ) {
1122 return array( $key, $wgLanguageCode );
1125 $message = implode( '/', $pieces );
1127 return array( $message, $lang );
1131 * Get all message keys stored in the message cache for a given language.
1132 * If $code is the content language code, this will return all message keys
1133 * for which MediaWiki:msgkey exists. If $code is another language code, this
1134 * will ONLY return message keys for which MediaWiki:msgkey/$code exists.
1135 * @param string $code Language code
1136 * @return array Array of message keys (strings)
1138 public function getAllMessageKeys( $code ) {
1140 $this->load( $code );
1141 if ( !isset( $this->mCache
[$code] ) ) {
1142 // Apparently load() failed
1145 // Remove administrative keys
1146 $cache = $this->mCache
[$code];
1147 unset( $cache['VERSION'] );
1148 unset( $cache['EXPIRY'] );
1149 // Remove any !NONEXISTENT keys
1150 $cache = array_diff( $cache, array( '!NONEXISTENT' ) );
1152 // Keys may appear with a capital first letter. lcfirst them.
1153 return array_map( array( $wgContLang, 'lcfirst' ), array_keys( $cache ) );