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 );
32 * Performs various MediaWiki namespace-related functions
36 const FOR_UPDATE
= 1; // force message reload
38 /** How long to wait for memcached locks */
40 /** How long memcached locks last */
44 * Process local cache of loaded messages that are defined in
45 * MediaWiki namespace. First array level is a language code,
46 * second level is message key and the values are either message
47 * content prefixed with space, or !NONEXISTENT for negative
54 * Should mean that database cannot be used, but check
60 * Lifetime for cache, used by object caching.
61 * Set on construction, see __construct().
66 * Message cache has its own parser which it uses to transform
69 protected $mParserOptions, $mParser;
72 * Variable for tracking which variables are already loaded
73 * @var array $mLoadedLanguages
75 protected $mLoadedLanguages = array();
78 * @var bool $mInParser
80 protected $mInParser = false;
84 /** @var WANObjectCache */
90 * @var MessageCache $instance
92 private static $instance;
95 * Get the signleton instance of this class
98 * @return MessageCache
100 public static function singleton() {
101 if ( is_null( self
::$instance ) ) {
102 global $wgUseDatabaseMessages, $wgMsgCacheExpiry;
103 self
::$instance = new self(
104 wfGetMessageCacheStorage(),
105 $wgUseDatabaseMessages,
110 return self
::$instance;
114 * Destroy the singleton instance
118 public static function destroyInstance() {
119 self
::$instance = null;
123 * Normalize message key input
125 * @param string $key Input message key to be normalized
126 * @return string Normalized message key
128 public static function normalizeKey( $key ) {
130 $lckey = strtr( $key, ' ', '_' );
131 if ( ord( $lckey ) < 128 ) {
132 $lckey[0] = strtolower( $lckey[0] );
134 $lckey = $wgContLang->lcfirst( $lckey );
141 * @param BagOStuff $memCached A cache instance. If none, fall back to CACHE_NONE.
143 * @param int $expiry Lifetime for cache. @see $mExpiry.
145 function __construct( $memCached, $useDB, $expiry ) {
146 global $wgUseLocalMessageCache;
149 $memCached = wfGetCache( CACHE_NONE
);
152 $this->mMemc
= $memCached;
153 $this->mDisable
= !$useDB;
154 $this->mExpiry
= $expiry;
156 if ( $wgUseLocalMessageCache ) {
157 $this->localCache
= ObjectCache
::newAccelerator( CACHE_NONE
);
159 $this->localCache
= wfGetCache( CACHE_NONE
);
162 $this->wanCache
= ObjectCache
::getMainWANInstance();
166 * ParserOptions is lazy initialised.
168 * @return ParserOptions
170 function getParserOptions() {
171 if ( !$this->mParserOptions
) {
172 $this->mParserOptions
= new ParserOptions
;
173 $this->mParserOptions
->setEditSection( false );
176 return $this->mParserOptions
;
180 * Try to load the cache from APC.
182 * @param string $code Optional language code, see documenation of load().
183 * @return array|bool The cache array, or false if not in cache.
185 protected function getLocalCache( $code ) {
186 $cacheKey = wfMemcKey( __CLASS__
, $code );
188 return $this->localCache
->get( $cacheKey );
192 * Save the cache to APC.
194 * @param string $code
195 * @param array $cache The cache array
197 protected function saveToLocalCache( $code, $cache ) {
198 $cacheKey = wfMemcKey( __CLASS__
, $code );
199 $this->localCache
->set( $cacheKey, $cache );
203 * Loads messages from caches or from database in this order:
204 * (1) local message cache (if $wgUseLocalMessageCache is enabled)
206 * (3) from the database.
208 * When succesfully loading from (2) or (3), all higher level caches are
209 * updated for the newest version.
211 * Nothing is loaded if member variable mDisable is true, either manually
212 * set by calling code or if message loading fails (is this possible?).
214 * Returns true if cache is already populated or it was succesfully populated,
215 * or false if populating empty cache fails. Also returns true if MessageCache
218 * @param bool|string $code Language to which load messages
219 * @param integer $mode Use MessageCache::FOR_UPDATE to skip process cache
220 * @throws MWException
223 function load( $code = false, $mode = null ) {
224 if ( !is_string( $code ) ) {
225 # This isn't really nice, so at least make a note about it and try to
227 wfDebug( __METHOD__
. " called without providing a language code\n" );
231 # Don't do double loading...
232 if ( isset( $this->mLoadedLanguages
[$code] ) && $mode != self
::FOR_UPDATE
) {
236 # 8 lines of code just to say (once) that message cache is disabled
237 if ( $this->mDisable
) {
238 static $shownDisabled = false;
239 if ( !$shownDisabled ) {
240 wfDebug( __METHOD__
. ": disabled\n" );
241 $shownDisabled = true;
247 # Loading code starts
248 $success = false; # Keep track of success
249 $staleCache = false; # a cache array with expired data, or false if none has been loaded
250 $where = array(); # Debug info, delayed to avoid spamming debug log too much
252 # Hash of the contents is stored in memcache, to detect if data-center cache
253 # or local cache goes out of date (e.g. due to replace() on some other server)
254 list( $hash, $hashVolatile ) = $this->getValidationHash( $code );
256 # Try the local cache and check against the cluster hash key...
257 $cache = $this->getLocalCache( $code );
259 $where[] = 'local cache is empty';
260 } elseif ( !isset( $cache['HASH'] ) ||
$cache['HASH'] !== $hash ) {
261 $where[] = 'local cache has the wrong hash';
262 $staleCache = $cache;
263 } elseif ( $this->isCacheExpired( $cache ) ) {
264 $where[] = 'local cache is expired';
265 $staleCache = $cache;
266 } elseif ( $hashVolatile ) {
267 $where[] = 'local cache validation key is expired/volatile';
268 $staleCache = $cache;
270 $where[] = 'got from local cache';
272 $this->mCache
[$code] = $cache;
276 $cacheKey = wfMemcKey( 'messages', $code ); # Key in memc for messages
277 # Try the global cache. If it is empty, try to acquire a lock. If
278 # the lock can't be acquired, wait for the other thread to finish
279 # and then try the global cache a second time.
280 for ( $failedAttempts = 0; $failedAttempts <= 1; $failedAttempts++
) {
281 if ( $hashVolatile && $staleCache ) {
282 # Do not bother fetching the whole cache blob to avoid I/O.
283 # Instead, just try to get the non-blocking $statusKey lock
284 # below, and use the local stale value if it was not acquired.
285 $where[] = 'global cache is presumed expired';
287 $cache = $this->mMemc
->get( $cacheKey );
289 $where[] = 'global cache is empty';
290 } elseif ( $this->isCacheExpired( $cache ) ) {
291 $where[] = 'global cache is expired';
292 $staleCache = $cache;
293 } elseif ( $hashVolatile ) {
294 # DB results are slave lag prone until the holdoff TTL passes.
295 # By then, updates should be reflected in loadFromDBWithLock().
296 # One thread renerates the cache while others use old values.
297 $where[] = 'global cache is expired/volatile';
298 $staleCache = $cache;
300 $where[] = 'got from global cache';
301 $this->mCache
[$code] = $cache;
302 $this->saveToCaches( $cache, 'local-only', $code );
308 # Done, no need to retry
312 # We need to call loadFromDB. Limit the concurrency to one process.
313 # This prevents the site from going down when the cache expires.
314 # Note that the DB slam protection lock here is non-blocking.
315 $loadStatus = $this->loadFromDBWithLock( $code, $where, $mode );
316 if ( $loadStatus === true ) {
319 } elseif ( $staleCache ) {
320 # Use the stale cache while some other thread constructs the new one
321 $where[] = 'using stale cache';
322 $this->mCache
[$code] = $staleCache;
325 } elseif ( $failedAttempts > 0 ) {
326 # Already blocked once, so avoid another lock/unlock cycle.
327 # This case will typically be hit if memcached is down, or if
328 # loadFromDB() takes longer than LOCK_WAIT.
329 $where[] = "could not acquire status key.";
331 } elseif ( $loadStatus === 'cantacquire' ) {
332 # Wait for the other thread to finish, then retry. Normally,
333 # the memcached get() will then yeild the other thread's result.
334 $where[] = 'waited for other thread to complete';
335 $this->getReentrantScopedLock( $cacheKey );
337 # Disable cache; $loadStatus is 'disabled'
344 $where[] = 'loading FAILED - cache is disabled';
345 $this->mDisable
= true;
346 $this->mCache
= false;
347 # This used to throw an exception, but that led to nasty side effects like
348 # the whole wiki being instantly down if the memcached server died
350 # All good, just record the success
351 $this->mLoadedLanguages
[$code] = true;
354 $info = implode( ', ', $where );
355 wfDebugLog( 'MessageCache', __METHOD__
. ": Loading $code... $info\n" );
361 * @param string $code
362 * @param array $where List of wfDebug() comments
363 * @param integer $mode Use MessageCache::FOR_UPDATE to use DB_MASTER
364 * @return bool|string True on success or one of ("cantacquire", "disabled")
366 protected function loadFromDBWithLock( $code, array &$where, $mode = null ) {
367 global $wgUseLocalMessageCache;
369 # If cache updates on all levels fail, give up on message overrides.
370 # This is to avoid easy site outages; see $saveSuccess comments below.
371 $statusKey = wfMemcKey( 'messages', $code, 'status' );
372 $status = $this->mMemc
->get( $statusKey );
373 if ( $status === 'error' ) {
374 $where[] = "could not load; method is still globally disabled";
378 # Now let's regenerate
379 $where[] = 'loading from database';
381 # Lock the cache to prevent conflicting writes.
382 # This lock is non-blocking so stale cache can quickly be used.
383 # Note that load() will call a blocking getReentrantScopedLock()
384 # after this if it really need to wait for any current thread.
385 $cacheKey = wfMemcKey( 'messages', $code );
386 $scopedLock = $this->getReentrantScopedLock( $cacheKey, 0 );
387 if ( !$scopedLock ) {
388 $where[] = 'could not acquire main lock';
389 return 'cantacquire';
392 $cache = $this->loadFromDB( $code, $mode );
393 $this->mCache
[$code] = $cache;
394 $saveSuccess = $this->saveToCaches( $cache, 'all', $code );
396 if ( !$saveSuccess ) {
397 # Cache save has failed.
398 # There are two main scenarios where this could be a problem:
400 # - The cache is more than the maximum size (typically
403 # - Memcached has no space remaining in the relevant slab
404 # class. This is unlikely with recent versions of
407 # Either way, if there is a local cache, nothing bad will
408 # happen. If there is no local cache, disabling the message
409 # cache for all requests avoids incurring a loadFromDB()
410 # overhead on every request, and thus saves the wiki from
411 # complete downtime under moderate traffic conditions.
412 if ( !$wgUseLocalMessageCache ) {
413 $this->mMemc
->set( $statusKey, 'error', 60 * 5 );
414 $where[] = 'could not save cache, disabled globally for 5 minutes';
416 $where[] = "could not save global cache";
424 * Loads cacheable messages from the database. Messages bigger than
425 * $wgMaxMsgCacheEntrySize are assigned a special value, and are loaded
426 * on-demand from the database later.
428 * @param string $code Language code
429 * @param integer $mode Use MessageCache::FOR_UPDATE to skip process cache
430 * @return array Loaded messages for storing in caches
432 function loadFromDB( $code, $mode = null ) {
433 global $wgMaxMsgCacheEntrySize, $wgLanguageCode, $wgAdaptiveMessageCache;
435 $dbr = wfGetDB( ( $mode == self
::FOR_UPDATE
) ? DB_MASTER
: DB_SLAVE
);
441 'page_is_redirect' => 0,
442 'page_namespace' => NS_MEDIAWIKI
,
446 if ( $wgAdaptiveMessageCache && $code !== $wgLanguageCode ) {
447 if ( !isset( $this->mCache
[$wgLanguageCode] ) ) {
448 $this->load( $wgLanguageCode );
450 $mostused = array_keys( $this->mCache
[$wgLanguageCode] );
451 foreach ( $mostused as $key => $value ) {
452 $mostused[$key] = "$value/$code";
456 if ( count( $mostused ) ) {
457 $conds['page_title'] = $mostused;
458 } elseif ( $code !== $wgLanguageCode ) {
459 $conds[] = 'page_title' . $dbr->buildLike( $dbr->anyString(), '/', $code );
461 # Effectively disallows use of '/' character in NS_MEDIAWIKI for uses
462 # other than language code.
463 $conds[] = 'page_title NOT' . $dbr->buildLike( $dbr->anyString(), '/', $dbr->anyString() );
466 # Conditions to fetch oversized pages to ignore them
468 $bigConds[] = 'page_len > ' . intval( $wgMaxMsgCacheEntrySize );
470 # Load titles for all oversized pages in the MediaWiki namespace
471 $res = $dbr->select( 'page', 'page_title', $bigConds, __METHOD__
. "($code)-big" );
472 foreach ( $res as $row ) {
473 $cache[$row->page_title
] = '!TOO BIG';
476 # Conditions to load the remaining pages with their contents
477 $smallConds = $conds;
478 $smallConds[] = 'page_latest=rev_id';
479 $smallConds[] = 'rev_text_id=old_id';
480 $smallConds[] = 'page_len <= ' . intval( $wgMaxMsgCacheEntrySize );
483 array( 'page', 'revision', 'text' ),
484 array( 'page_title', 'old_text', 'old_flags' ),
486 __METHOD__
. "($code)-small"
489 foreach ( $res as $row ) {
490 $text = Revision
::getRevisionText( $row );
491 if ( $text === false ) {
492 // Failed to fetch data; possible ES errors?
493 // Store a marker to fetch on-demand as a workaround...
498 . ": failed to load message page text for {$row->page_title} ($code)"
501 $entry = ' ' . $text;
503 $cache[$row->page_title
] = $entry;
506 $cache['VERSION'] = MSG_CACHE_VERSION
;
508 $cache['HASH'] = md5( serialize( $cache ) );
509 $cache['EXPIRY'] = wfTimestamp( TS_MW
, time() +
$this->mExpiry
);
515 * Updates cache as necessary when message page is changed
517 * @param string|bool $title Name of the page changed (false if deleted)
518 * @param mixed $text New contents of the page.
520 public function replace( $title, $text ) {
521 global $wgMaxMsgCacheEntrySize, $wgContLang, $wgLanguageCode;
523 if ( $this->mDisable
) {
527 list( $msg, $code ) = $this->figureMessage( $title );
528 if ( strpos( $title, '/' ) !== false && $code === $wgLanguageCode ) {
529 // Content language overrides do not use the /<code> suffix
533 // Note that if the cache is volatile, load() may trigger a DB fetch.
534 // In that case we reenter/reuse the existing cache key lock to avoid
535 // a self-deadlock. This is safe as no reads happen *directly* in this
536 // method between getReentrantScopedLock() and load() below. There is
537 // no risk of data "changing under our feet" for replace().
538 $cacheKey = wfMemcKey( 'messages', $code );
539 $scopedLock = $this->getReentrantScopedLock( $cacheKey );
540 $this->load( $code, self
::FOR_UPDATE
);
542 $titleKey = wfMemcKey( 'messages', 'individual', $title );
543 if ( $text === false ) {
544 // Article was deleted
545 $this->mCache
[$code][$title] = '!NONEXISTENT';
546 $this->wanCache
->delete( $titleKey );
547 } elseif ( strlen( $text ) > $wgMaxMsgCacheEntrySize ) {
549 $this->mCache
[$code][$title] = '!TOO BIG';
550 $this->wanCache
->set( $titleKey, ' ' . $text, $this->mExpiry
);
552 $this->mCache
[$code][$title] = ' ' . $text;
553 $this->wanCache
->delete( $titleKey );
556 // Mark this cache as definitely "latest" (non-volatile) so
557 // load() calls do try to refresh the cache with slave data
558 $this->mCache
[$code]['LATEST'] = time();
560 // Update caches if the lock was acquired
562 $this->saveToCaches( $this->mCache
[$code], 'all', $code );
565 ScopedCallback
::consume( $scopedLock );
566 // Relay the purge to APC and other DCs
567 $this->wanCache
->touchCheckKey( wfMemcKey( 'messages', $code ) );
569 // Also delete cached sidebar... just in case it is affected
570 $codes = array( $code );
571 if ( $code === 'en' ) {
572 // Delete all sidebars, like for example on action=purge on the
574 $codes = array_keys( Language
::fetchLanguageNames() );
577 foreach ( $codes as $code ) {
578 $sidebarKey = wfMemcKey( 'sidebar', $code );
579 $this->wanCache
->delete( $sidebarKey, 5 );
582 // Update the message in the message blob store
583 $blobStore = new MessageBlobStore();
584 $blobStore->updateMessage( $wgContLang->lcfirst( $msg ) );
586 Hooks
::run( 'MessageCacheReplace', array( $title, $text ) );
590 * Is the given cache array expired due to time passing or a version change?
592 * @param array $cache
595 protected function isCacheExpired( $cache ) {
596 if ( !isset( $cache['VERSION'] ) ||
!isset( $cache['EXPIRY'] ) ) {
599 if ( $cache['VERSION'] != MSG_CACHE_VERSION
) {
602 if ( wfTimestampNow() >= $cache['EXPIRY'] ) {
610 * Shortcut to update caches.
612 * @param array $cache Cached messages with a version.
613 * @param string $dest Either "local-only" to save to local caches only
614 * or "all" to save to all caches.
615 * @param string|bool $code Language code (default: false)
618 protected function saveToCaches( array $cache, $dest, $code = false ) {
619 if ( $dest === 'all' ) {
620 $cacheKey = wfMemcKey( 'messages', $code );
621 $success = $this->mMemc
->set( $cacheKey, $cache );
626 $this->setValidationHash( $code, $cache );
627 $this->saveToLocalCache( $code, $cache );
633 * Get the md5 used to validate the local APC cache
635 * @param string $code
636 * @return array (hash or false, bool expiry/volatility status)
638 protected function getValidationHash( $code ) {
640 $value = $this->wanCache
->get(
641 wfMemcKey( 'messages', $code, 'hash', 'v1' ),
643 array( wfMemcKey( 'messages', $code ) )
647 // No hash found at all; cache must regenerate to be safe
651 $hash = $value['hash'];
652 if ( ( time() - $value['latest'] ) < WANObjectCache
::HOLDOFF_TTL
) {
653 // Cache was recently updated via replace() and should be up-to-date
656 // See if the "check" key was bumped after the hash was generated
657 $expired = ( $curTTL < 0 );
661 return array( $hash, $expired );
665 * Set the md5 used to validate the local disk cache
667 * If $cache has a 'LATEST' UNIX timestamp key, then the hash will not
668 * be treated as "volatile" by getValidationHash() for the next few seconds
670 * @param string $code
671 * @param array $cache Cached messages with a version
673 protected function setValidationHash( $code, array $cache ) {
674 $this->wanCache
->set(
675 wfMemcKey( 'messages', $code, 'hash', 'v1' ),
677 'hash' => $cache['HASH'],
678 'latest' => isset( $cache['LATEST'] ) ?
$cache['LATEST'] : 0
680 WANObjectCache
::TTL_NONE
685 * @param string $key A language message cache key that stores blobs
686 * @param integer $timeout Wait timeout in seconds
687 * @return null|ScopedCallback
689 protected function getReentrantScopedLock( $key, $timeout = self
::WAIT_SEC
) {
690 return $this->mMemc
->getScopedLock( $key, $timeout, self
::LOCK_TTL
, __METHOD__
);
694 * Get a message from either the content language or the user language.
696 * First, assemble a list of languages to attempt getting the message from. This
697 * chain begins with the requested language and its fallbacks and then continues with
698 * the content language and its fallbacks. For each language in the chain, the following
699 * process will occur (in this order):
700 * 1. If a language-specific override, i.e., [[MW:msg/lang]], is available, use that.
701 * Note: for the content language, there is no /lang subpage.
702 * 2. Fetch from the static CDB cache.
703 * 3. If available, check the database for fallback language overrides.
705 * This process provides a number of guarantees. When changing this code, make sure all
706 * of these guarantees are preserved.
707 * * If the requested language is *not* the content language, then the CDB cache for that
708 * specific language will take precedence over the root database page ([[MW:msg]]).
709 * * Fallbacks will be just that: fallbacks. A fallback language will never be reached if
710 * the message is available *anywhere* in the language for which it is a fallback.
712 * @param string $key The message key
713 * @param bool $useDB If true, look for the message in the DB, false
714 * to use only the compiled l10n cache.
715 * @param bool|string|object $langcode Code of the language to get the message for.
716 * - If string and a valid code, will create a standard language object
717 * - If string but not a valid code, will create a basic language object
718 * - If boolean and false, create object from the current users language
719 * - If boolean and true, create object from the wikis content language
720 * - If language object, use it as given
721 * @param bool $isFullKey Specifies whether $key is a two part key "msg/lang".
723 * @throws MWException When given an invalid key
724 * @return string|bool False if the message doesn't exist, otherwise the
725 * message (which can be empty)
727 function get( $key, $useDB = true, $langcode = true, $isFullKey = false ) {
730 if ( is_int( $key ) ) {
731 // Fix numerical strings that somehow become ints
734 } elseif ( !is_string( $key ) ) {
735 throw new MWException( 'Non-string key given' );
736 } elseif ( $key === '' ) {
737 // Shortcut: the empty key is always missing
741 // For full keys, get the language code from the key
742 $pos = strrpos( $key, '/' );
743 if ( $isFullKey && $pos !== false ) {
744 $langcode = substr( $key, $pos +
1 );
745 $key = substr( $key, 0, $pos );
748 // Normalise title-case input (with some inlining)
749 $lckey = MessageCache
::normalizeKey( $key );
751 Hooks
::run( 'MessageCache::get', array( &$lckey ) );
753 if ( ord( $lckey ) < 128 ) {
754 $uckey = ucfirst( $lckey );
756 $uckey = $wgContLang->ucfirst( $lckey );
759 // Loop through each language in the fallback list until we find something useful
760 $lang = wfGetLangObj( $langcode );
761 $message = $this->getMessageFromFallbackChain(
765 !$this->mDisable
&& $useDB
768 // If we still have no message, maybe the key was in fact a full key so try that
769 if ( $message === false ) {
770 $parts = explode( '/', $lckey );
771 // We may get calls for things that are http-urls from sidebar
772 // Let's not load nonexistent languages for those
773 // They usually have more than one slash.
774 if ( count( $parts ) == 2 && $parts[1] !== '' ) {
775 $message = Language
::getMessageFor( $parts[0], $parts[1] );
776 if ( $message === null ) {
782 // Post-processing if the message exists
783 if ( $message !== false ) {
785 $message = str_replace(
787 # Fix for trailing whitespace, removed by textarea
789 # Fix for NBSP, converted to space by firefox
806 * Given a language, try and fetch a message from that language, then the
807 * fallbacks of that language, then the site language, then the fallbacks for the
810 * @param Language $lang Requested language
811 * @param string $lckey Lowercase key for the message
812 * @param string $uckey Uppercase key for the message
813 * @param bool $useDB Whether to use the database
815 * @see MessageCache::get
816 * @return string|bool The message, or false if not found
818 protected function getMessageFromFallbackChain( $lang, $lckey, $uckey, $useDB ) {
819 global $wgLanguageCode, $wgContLang;
821 $langcode = $lang->getCode();
824 // First try the requested language.
826 if ( $langcode === $wgLanguageCode ) {
827 // Messages created in the content language will not have the /lang extension
828 $message = $this->getMsgFromNamespace( $uckey, $langcode );
830 $message = $this->getMsgFromNamespace( "$uckey/$langcode", $langcode );
834 if ( $message !== false ) {
838 // Check the CDB cache
839 $message = $lang->getMessage( $lckey );
840 if ( $message !== null ) {
844 list( $fallbackChain, $siteFallbackChain ) =
845 Language
::getFallbacksIncludingSiteLanguage( $langcode );
847 // Next try checking the database for all of the fallback languages of the requested language.
849 foreach ( $fallbackChain as $code ) {
850 if ( $code === $wgLanguageCode ) {
851 // Messages created in the content language will not have the /lang extension
852 $message = $this->getMsgFromNamespace( $uckey, $code );
854 $message = $this->getMsgFromNamespace( "$uckey/$code", $code );
857 if ( $message !== false ) {
858 // Found the message.
864 // Now try checking the site language.
866 $message = $this->getMsgFromNamespace( $uckey, $wgLanguageCode );
867 if ( $message !== false ) {
872 $message = $wgContLang->getMessage( $lckey );
873 if ( $message !== null ) {
877 // Finally try the DB for the site language's fallbacks.
879 foreach ( $siteFallbackChain as $code ) {
880 $message = $this->getMsgFromNamespace( "$uckey/$code", $code );
881 if ( $message === false && $code === $wgLanguageCode ) {
882 // Messages created in the content language will not have the /lang extension
883 $message = $this->getMsgFromNamespace( $uckey, $code );
886 if ( $message !== false ) {
887 // Found the message.
897 * Get a message from the MediaWiki namespace, with caching. The key must
898 * first be converted to two-part lang/msg form if necessary.
900 * Unlike self::get(), this function doesn't resolve fallback chains, and
901 * some callers require this behavior. LanguageConverter::parseCachedTable()
902 * and self::get() are some examples in core.
904 * @param string $title Message cache key with initial uppercase letter.
905 * @param string $code Code denoting the language to try.
906 * @return string|bool The message, or false if it does not exist or on error
908 function getMsgFromNamespace( $title, $code ) {
909 $this->load( $code );
910 if ( isset( $this->mCache
[$code][$title] ) ) {
911 $entry = $this->mCache
[$code][$title];
912 if ( substr( $entry, 0, 1 ) === ' ' ) {
913 // The message exists, so make sure a string
915 return (string)substr( $entry, 1 );
916 } elseif ( $entry === '!NONEXISTENT' ) {
918 } elseif ( $entry === '!TOO BIG' ) {
919 // Fall through and try invididual message cache below
922 // XXX: This is not cached in process cache, should it?
924 Hooks
::run( 'MessagesPreLoad', array( $title, &$message ) );
925 if ( $message !== false ) {
932 # Try the individual message cache
933 $titleKey = wfMemcKey( 'messages', 'individual', $title );
934 $entry = $this->wanCache
->get( $titleKey );
936 if ( substr( $entry, 0, 1 ) === ' ' ) {
937 $this->mCache
[$code][$title] = $entry;
939 // The message exists, so make sure a string
941 return (string)substr( $entry, 1 );
942 } elseif ( $entry === '!NONEXISTENT' ) {
943 $this->mCache
[$code][$title] = '!NONEXISTENT';
947 # Corrupt/obsolete entry, delete it
948 $this->wanCache
->delete( $titleKey );
952 # Try loading it from the database
953 $revision = Revision
::newFromTitle( Title
::makeTitle( NS_MEDIAWIKI
, $title ) );
955 $content = $revision->getContent();
957 // A possibly temporary loading failure.
960 __METHOD__
. ": failed to load message page text for {$title} ($code)"
962 $message = null; // no negative caching
964 // XXX: Is this the right way to turn a Content object into a message?
965 // NOTE: $content is typically either WikitextContent, JavaScriptContent or
966 // CssContent. MessageContent is *not* used for storing messages, it's
967 // only used for wrapping them when needed.
968 $message = $content->getWikitextForTransclusion();
970 if ( $message === false ||
$message === null ) {
973 __METHOD__
. ": message content doesn't provide wikitext "
974 . "(content model: " . $content->getModel() . ")"
977 $message = false; // negative caching
979 $this->mCache
[$code][$title] = ' ' . $message;
980 $this->wanCache
->set( $titleKey, ' ' . $message, $this->mExpiry
);
984 $message = false; // negative caching
987 if ( $message === false ) { // negative caching
988 $this->mCache
[$code][$title] = '!NONEXISTENT';
989 $this->wanCache
->set( $titleKey, '!NONEXISTENT', $this->mExpiry
);
996 * @param string $message
997 * @param bool $interface
998 * @param string $language Language code
999 * @param Title $title
1002 function transform( $message, $interface = false, $language = null, $title = null ) {
1003 // Avoid creating parser if nothing to transform
1004 if ( strpos( $message, '{{' ) === false ) {
1008 if ( $this->mInParser
) {
1012 $parser = $this->getParser();
1014 $popts = $this->getParserOptions();
1015 $popts->setInterfaceMessage( $interface );
1016 $popts->setTargetLanguage( $language );
1018 $userlang = $popts->setUserLang( $language );
1019 $this->mInParser
= true;
1020 $message = $parser->transformMsg( $message, $popts, $title );
1021 $this->mInParser
= false;
1022 $popts->setUserLang( $userlang );
1031 function getParser() {
1032 global $wgParser, $wgParserConf;
1033 if ( !$this->mParser
&& isset( $wgParser ) ) {
1034 # Do some initialisation so that we don't have to do it twice
1035 $wgParser->firstCallInit();
1036 # Clone it and store it
1037 $class = $wgParserConf['class'];
1038 if ( $class == 'ParserDiffTest' ) {
1040 $this->mParser
= new $class( $wgParserConf );
1042 $this->mParser
= clone $wgParser;
1046 return $this->mParser
;
1050 * @param string $text
1051 * @param Title $title
1052 * @param bool $linestart Whether or not this is at the start of a line
1053 * @param bool $interface Whether this is an interface message
1054 * @param string $language Language code
1055 * @return ParserOutput|string
1057 public function parse( $text, $title = null, $linestart = true,
1058 $interface = false, $language = null
1060 if ( $this->mInParser
) {
1061 return htmlspecialchars( $text );
1064 $parser = $this->getParser();
1065 $popts = $this->getParserOptions();
1066 $popts->setInterfaceMessage( $interface );
1067 $popts->setTargetLanguage( $language );
1069 if ( !$title ||
!$title instanceof Title
) {
1071 wfDebugLog( 'GlobalTitleFail', __METHOD__
. ' called by ' .
1072 wfGetAllCallers( 5 ) . ' with no title set.' );
1075 // Sometimes $wgTitle isn't set either...
1077 # It's not uncommon having a null $wgTitle in scripts. See r80898
1078 # Create a ghost title in such case
1079 $title = Title
::makeTitle( NS_SPECIAL
, 'Badtitle/title not set in ' . __METHOD__
);
1082 $this->mInParser
= true;
1083 $res = $parser->parse( $text, $title, $popts, $linestart );
1084 $this->mInParser
= false;
1089 function disable() {
1090 $this->mDisable
= true;
1094 $this->mDisable
= false;
1098 * Clear all stored messages. Mainly used after a mass rebuild.
1101 $langs = Language
::fetchLanguageNames( null, 'mw' );
1102 foreach ( array_keys( $langs ) as $code ) {
1103 # Global and local caches
1104 $this->wanCache
->touchCheckKey( wfMemcKey( 'messages', $code ) );
1107 $this->mLoadedLanguages
= array();
1111 * @param string $key
1114 public function figureMessage( $key ) {
1115 global $wgLanguageCode;
1117 $pieces = explode( '/', $key );
1118 if ( count( $pieces ) < 2 ) {
1119 return array( $key, $wgLanguageCode );
1122 $lang = array_pop( $pieces );
1123 if ( !Language
::fetchLanguageName( $lang, null, 'mw' ) ) {
1124 return array( $key, $wgLanguageCode );
1127 $message = implode( '/', $pieces );
1129 return array( $message, $lang );
1133 * Get all message keys stored in the message cache for a given language.
1134 * If $code is the content language code, this will return all message keys
1135 * for which MediaWiki:msgkey exists. If $code is another language code, this
1136 * will ONLY return message keys for which MediaWiki:msgkey/$code exists.
1137 * @param string $code Language code
1138 * @return array Array of message keys (strings)
1140 public function getAllMessageKeys( $code ) {
1142 $this->load( $code );
1143 if ( !isset( $this->mCache
[$code] ) ) {
1144 // Apparently load() failed
1147 // Remove administrative keys
1148 $cache = $this->mCache
[$code];
1149 unset( $cache['VERSION'] );
1150 unset( $cache['EXPIRY'] );
1151 // Remove any !NONEXISTENT keys
1152 $cache = array_diff( $cache, array( '!NONEXISTENT' ) );
1154 // Keys may appear with a capital first letter. lcfirst them.
1155 return array_map( array( $wgContLang, 'lcfirst' ), array_keys( $cache ) );