MediaWiki  master
MessageCache Class Reference

Cache of messages that are defined by MediaWiki namespace pages or by hooks. More...

Collaboration diagram for MessageCache:

Public Member Functions

 __construct (WANObjectCache $wanCache, BagOStuff $clusterCache, BagOStuff $serverCache, $useDB, Language $contLang=null)
 
 clear ()
 Clear all stored messages in global and local cache. More...
 
 disable ()
 
 enable ()
 
 figureMessage ( $key)
 
 get ( $key, $useDB=true, $langcode=true)
 Get a message from either the content language or the user language. More...
 
 getAllMessageKeys ( $code)
 Get all message keys stored in the message cache for a given language. More...
 
 getCheckKey ( $code)
 
 getMsgFromNamespace ( $title, $code)
 Get a message from the MediaWiki namespace, with caching. More...
 
 getParser ()
 
 getParserOptions ()
 ParserOptions is lazy initialised. More...
 
 isDisabled ()
 Whether DB/cache usage is disabled for determining messages. More...
 
 parse ( $text, $title=null, $linestart=true, $interface=false, $language=null)
 
 refreshAndReplaceInternal ( $code, array $replacements)
 
 replace ( $title, $text)
 Updates cache as necessary when message page is changed. More...
 
 transform ( $message, $interface=false, $language=null, $title=null)
 
 updateMessageOverride (Title $title, Content $content=null)
 Purge message caches when a MediaWiki: page is created, updated, or deleted. More...
 

Static Public Member Functions

static normalizeKey ( $key)
 Normalize message key input. More...
 
static singleton ()
 Get the singleton instance of this class. More...
 

Public Attributes

const FOR_UPDATE = 1
 
const LOCK_TTL = 30
 How long memcached locks last. More...
 
const WAIT_SEC = 15
 How long to wait for memcached locks. More...
 

Protected Member Functions

 getLocalCache ( $code)
 Try to load the cache from APC. More...
 
 getMessageFromFallbackChain ( $lang, $lckey, $useDB)
 Given a language, try and fetch messages from that language. More...
 
 getReentrantScopedLock ( $key, $timeout=self::WAIT_SEC)
 
 getValidationHash ( $code)
 Get the md5 used to validate the local APC cache. More...
 
 isCacheExpired ( $cache)
 Is the given cache array expired due to time passing or a version change? More...
 
 load ( $code, $mode=null)
 Loads messages from caches or from database in this order: (1) local message cache (if $wgUseLocalMessageCache is enabled) (2) memcached (3) from the database. More...
 
 loadFromDB ( $code, $mode=null)
 Loads cacheable messages from the database. More...
 
 loadFromDBWithLock ( $code, array &$where, $mode=null)
 
 saveToCaches (array $cache, $dest, $code=false)
 Shortcut to update caches. More...
 
 saveToLocalCache ( $code, $cache)
 Save the cache to APC. More...
 
 setValidationHash ( $code, array $cache)
 Set the md5 used to validate the local disk cache. More...
 

Protected Attributes

MapCacheLRU $cache
 Process cache of loaded messages that are defined in MediaWiki namespace. More...
 
bool [] $cacheVolatile = []
 Map of (language code => boolean) More...
 
BagOStuff $clusterCache
 
Language $contLang
 
 $mDisable
 Should mean that database cannot be used, but check. More...
 
 $mInParser = false
 
Parser $mParser
 
ParserOptions $mParserOptions
 Message cache has its own parser which it uses to transform messages. More...
 
array $overridable
 Map of (lowercase message key => index) for all software defined messages. More...
 
BagOStuff $srvCache
 
WANObjectCache $wanCache
 

Private Member Functions

 bigMessageCacheKey ( $hash, $title)
 
 getMessageForLang ( $lang, $lckey, $useDB, &$alreadyTried)
 Given a language, try and fetch messages from that language and its fallbacks. More...
 
 getMessagePageName ( $langcode, $uckey)
 Get the message page name for a given language. More...
 
 getMessageTextFromContent (Content $content=null)
 
 isLanguageLoaded ( $lang)
 Whether the language was loaded and its data is still in the process cache. More...
 
 isMainCacheable ( $name, array $overridable)
 
 loadCachedMessagePageEntry ( $dbKey, $code, $hash)
 

Detailed Description

Cache of messages that are defined by MediaWiki namespace pages or by hooks.

Performs various MediaWiki namespace-related functions

Definition at line 40 of file MessageCache.php.

Constructor & Destructor Documentation

◆ __construct()

MessageCache::__construct ( WANObjectCache  $wanCache,
BagOStuff  $clusterCache,
BagOStuff  $serverCache,
  $useDB,
Language  $contLang = null 
)
Parameters
WANObjectCache$wanCache
BagOStuff$clusterCache
BagOStuff$serverCache
bool$useDBWhether to look for message overrides (e.g. MediaWiki: pages)
Language | null$contLangContent language of site

Definition at line 136 of file MessageCache.php.

References $clusterCache, and $wanCache.

Member Function Documentation

◆ bigMessageCacheKey()

MessageCache::bigMessageCacheKey (   $hash,
  $title 
)
private
Parameters
string$hashHash for this version of the entire key/value overrides map
string$titleMessage cache key with initial uppercase letter
Returns
string

Definition at line 1402 of file MessageCache.php.

References $title.

Referenced by loadCachedMessagePageEntry(), and refreshAndReplaceInternal().

◆ clear()

MessageCache::clear ( )

Clear all stored messages in global and local cache.

Mainly used after a mass rebuild

Definition at line 1285 of file MessageCache.php.

References Language\fetchLanguageNames(), and getCheckKey().

◆ disable()

MessageCache::disable ( )

Definition at line 1256 of file MessageCache.php.

◆ enable()

MessageCache::enable ( )

Definition at line 1260 of file MessageCache.php.

◆ figureMessage()

MessageCache::figureMessage (   $key)
Parameters
string$key
Returns
array

Definition at line 1297 of file MessageCache.php.

References $lang, $wgLanguageCode, and Language\fetchLanguageName().

Referenced by replace().

◆ get()

MessageCache::get (   $key,
  $useDB = true,
  $langcode = true 
)

Get a message from either the content language or the user language.

First, assemble a list of languages to attempt getting the message from. This chain begins with the requested language and its fallbacks and then continues with the content language and its fallbacks. For each language in the chain, the following process will occur (in this order):

  1. If a language-specific override, i.e., [[MW:msg/lang]], is available, use that. Note: for the content language, there is no /lang subpage.
  2. Fetch from the static CDB cache.
  3. If available, check the database for fallback language overrides.

This process provides a number of guarantees. When changing this code, make sure all of these guarantees are preserved.

  • If the requested language is not the content language, then the CDB cache for that specific language will take precedence over the root database page ([[MW:msg]]).
  • Fallbacks will be just that: fallbacks. A fallback language will never be reached if the message is available anywhere in the language for which it is a fallback.
Parameters
string$keyThe message key
bool$useDBIf true, look for the message in the DB, false to use only the compiled l10n cache.
bool | string | object$langcodeCode of the language to get the message for.
  • If string and a valid code, will create a standard language object
  • If string but not a valid code, will create a basic language object
  • If boolean and false, create object from the current users language
  • If boolean and true, create object from the wikis content language
  • If language object, use it as given
Exceptions
MWExceptionWhen given an invalid key
Returns
string|bool False if the message doesn't exist, otherwise the message (which can be empty)

Definition at line 856 of file MessageCache.php.

References Language\getMessageFor(), getMessageFromFallbackChain(), Hooks\run(), and wfGetLangObj().

◆ getAllMessageKeys()

MessageCache::getAllMessageKeys (   $code)

Get all message keys stored in the message cache for a given language.

If $code is the content language code, this will return all message keys for which MediaWiki:msgkey exists. If $code is another language code, this will ONLY return message keys for which MediaWiki:msgkey/$code exists.

Parameters
string$codeLanguage code
Returns
array Array of message keys (strings)

Definition at line 1323 of file MessageCache.php.

References MapCacheLRU\get(), and load().

◆ getCheckKey()

MessageCache::getCheckKey (   $code)
Parameters
string$codeLanguage code
Returns
string WAN cache key usable as a "check key" against language page edits

Definition at line 1365 of file MessageCache.php.

Referenced by clear(), getValidationHash(), and refreshAndReplaceInternal().

◆ getLocalCache()

MessageCache::getLocalCache (   $code)
protected

Try to load the cache from APC.

Parameters
string$codeOptional language code, see documentation of load().
Returns
array|bool The cache array, or false if not in cache.

Definition at line 190 of file MessageCache.php.

Referenced by load().

◆ getMessageForLang()

MessageCache::getMessageForLang (   $lang,
  $lckey,
  $useDB,
$alreadyTried 
)
private

Given a language, try and fetch messages from that language and its fallbacks.

See also
MessageCache::get
Parameters
Language | StubObject$langPreferred language
string$lckeyLowercase key for the message (as for localisation cache)
bool$useDBWhether to include messages from the wiki database
bool[]$alreadyTried Contains true for each language that has been tried already
Returns
string|bool The message, or false if not found

Definition at line 955 of file MessageCache.php.

References $lang, Language\getFallbacksFor(), getMessagePageName(), and getMsgFromNamespace().

Referenced by getMessageFromFallbackChain().

◆ getMessageFromFallbackChain()

MessageCache::getMessageFromFallbackChain (   $lang,
  $lckey,
  $useDB 
)
protected

Given a language, try and fetch messages from that language.

Will also consider fallbacks of that language, the site language, and fallbacks for the site language.

See also
MessageCache::get
Parameters
Language | StubObject$langPreferred language
string$lckeyLowercase key for the message (as for localisation cache)
bool$useDBWhether to include messages from the wiki database
Returns
string|bool The message, or false if not found

Definition at line 931 of file MessageCache.php.

References $lang, and getMessageForLang().

Referenced by get().

◆ getMessagePageName()

MessageCache::getMessagePageName (   $langcode,
  $uckey 
)
private

Get the message page name for a given language.

Parameters
string$langcode
string$uckeyUppercase key for the message
Returns
string The page name

Definition at line 1011 of file MessageCache.php.

References $wgLanguageCode.

Referenced by getMessageForLang().

◆ getMessageTextFromContent()

MessageCache::getMessageTextFromContent ( Content  $content = null)
private
Parameters
Content | null$contentContent or null if the message page does not exist
Returns
string|bool|null Returns false if $content is null and null on error

Definition at line 1373 of file MessageCache.php.

References $content.

Referenced by loadCachedMessagePageEntry(), loadFromDB(), refreshAndReplaceInternal(), and updateMessageOverride().

◆ getMsgFromNamespace()

MessageCache::getMsgFromNamespace (   $title,
  $code 
)

Get a message from the MediaWiki namespace, with caching.

The key must first be converted to two-part lang/msg form if necessary.

Unlike self::get(), this function doesn't resolve fallback chains, and some callers require this behavior. LanguageConverter::parseCachedTable() and self::get() are some examples in core.

Parameters
string$titleMessage cache key with initial uppercase letter
string$codeCode denoting the language to try
Returns
string|bool The message, or false if it does not exist or on error

Definition at line 1034 of file MessageCache.php.

References $title, isMainCacheable(), load(), loadCachedMessagePageEntry(), and Hooks\run().

Referenced by getMessageForLang().

◆ getParser()

MessageCache::getParser ( )
Returns
Parser

Definition at line 1191 of file MessageCache.php.

References $mParser, and $wgParserConf.

Referenced by parse(), and transform().

◆ getParserOptions()

MessageCache::getParserOptions ( )

ParserOptions is lazy initialised.

Returns
ParserOptions

Definition at line 158 of file MessageCache.php.

References $mParserOptions, and ParserOptions\newFromAnon().

Referenced by parse(), and transform().

◆ getReentrantScopedLock()

MessageCache::getReentrantScopedLock (   $key,
  $timeout = self::WAIT_SEC 
)
protected
Parameters
string$keyA language message cache key that stores blobs
int$timeoutWait timeout in seconds
Returns
null|ScopedCallback

Definition at line 819 of file MessageCache.php.

Referenced by load(), loadFromDBWithLock(), and refreshAndReplaceInternal().

◆ getValidationHash()

MessageCache::getValidationHash (   $code)
protected

Get the md5 used to validate the local APC cache.

Parameters
string$code
Returns
array (hash or false, bool expiry/volatility status)

Definition at line 765 of file MessageCache.php.

References getCheckKey(), and IExpiringStore\TTL_MINUTE.

Referenced by load().

◆ isCacheExpired()

MessageCache::isCacheExpired (   $cache)
protected

Is the given cache array expired due to time passing or a version change?

Parameters
array$cache
Returns
bool

Definition at line 722 of file MessageCache.php.

References MSG_CACHE_VERSION, and wfTimestampNow().

Referenced by load().

◆ isDisabled()

MessageCache::isDisabled ( )

Whether DB/cache usage is disabled for determining messages.

If so, this typically indicates either:

  • a) load() failed to find a cached copy nor query the DB
  • b) we are in a special context or error mode that cannot use the DB If the DB is ignored, any derived HTML output or cached objects may be wrong. To avoid long-term cache pollution, TTLs can be adjusted accordingly.
Returns
bool
Since
1.27

Definition at line 1276 of file MessageCache.php.

References $mDisable.

◆ isLanguageLoaded()

MessageCache::isLanguageLoaded (   $lang)
private

Whether the language was loaded and its data is still in the process cache.

Parameters
string$lang
Returns
bool

Definition at line 569 of file MessageCache.php.

References $lang.

Referenced by load().

◆ isMainCacheable()

MessageCache::isMainCacheable (   $name,
array  $overridable 
)
private
Parameters
string$nameMessage name (possibly with /code suffix)
array$overridableMap of (key => unused) for software-defined messages
Returns
bool

Definition at line 584 of file MessageCache.php.

Referenced by getMsgFromNamespace(), and loadFromDB().

◆ load()

MessageCache::load (   $code,
  $mode = null 
)
protected

Loads messages from caches or from database in this order: (1) local message cache (if $wgUseLocalMessageCache is enabled) (2) memcached (3) from the database.

When successfully loading from (2) or (3), all higher level caches are updated for the newest version.

Nothing is loaded if member variable mDisable is true, either manually set by calling code or if message loading fails (is this possible?).

Returns true if cache is already populated or it was successfully populated, or false if populating empty cache fails. Also returns true if MessageCache is disabled.

Parameters
string$codeLanguage to which load messages
int | null$modeUse MessageCache::FOR_UPDATE to skip process cache [optional]
Exceptions
InvalidArgumentException
Returns
bool

Definition at line 228 of file MessageCache.php.

References $cache, $success, MapCacheLRU\get(), getLocalCache(), Language\getMessageKeysFor(), getReentrantScopedLock(), getValidationHash(), isCacheExpired(), isLanguageLoaded(), loadFromDBWithLock(), saveToCaches(), MapCacheLRU\set(), wfDebug(), and wfDebugLog().

Referenced by getAllMessageKeys(), getMsgFromNamespace(), loadFromDB(), and refreshAndReplaceInternal().

◆ loadCachedMessagePageEntry()

MessageCache::loadCachedMessagePageEntry (   $dbKey,
  $code,
  $hash 
)
private
Parameters
string$dbKey
string$code
string$hash
Returns
string Either " <MESSAGE>" or "!NONEXISTANT"

Definition at line 1108 of file MessageCache.php.

References $content, $dbr, $title, bigMessageCacheKey(), DB_REPLICA, getMessageTextFromContent(), Title\makeTitle(), Revision\newKnownCurrent(), NS_MEDIAWIKI, IExpiringStore\TTL_HOUR, and wfGetDB().

Referenced by getMsgFromNamespace().

◆ loadFromDB()

MessageCache::loadFromDB (   $code,
  $mode = null 
)
protected

Loads cacheable messages from the database.

Messages bigger than $wgMaxMsgCacheEntrySize are assigned a special value, and are loaded on-demand from the database later.

Parameters
string$codeLanguage code
int | null$modeUse MessageCache::FOR_UPDATE to skip process cache
Returns
array Loaded messages for storing in caches

Definition at line 435 of file MessageCache.php.

References $cache, $content, $dbr, $res, $revQuery, $wgAdaptiveMessageCache, $wgLanguageCode, $wgMaxMsgCacheEntrySize, DB_MASTER, DB_REPLICA, Language\getMessageKeysFor(), getMessageTextFromContent(), isMainCacheable(), load(), MSG_CACHE_VERSION, NS_MEDIAWIKI, serialize(), wfDebugLog(), wfGetDB(), and wfTimestamp().

Referenced by loadFromDBWithLock(), and refreshAndReplaceInternal().

◆ loadFromDBWithLock()

MessageCache::loadFromDBWithLock (   $code,
array &  $where,
  $mode = null 
)
protected
Parameters
string$code
array&$whereList of wfDebug() comments
int | null$modeUse MessageCache::FOR_UPDATE to use DB_MASTER
Returns
bool|string True on success or one of ("cantacquire", "disabled")

Definition at line 373 of file MessageCache.php.

References getReentrantScopedLock(), loadFromDB(), and saveToCaches().

Referenced by load().

◆ normalizeKey()

static MessageCache::normalizeKey (   $key)
static

Normalize message key input.

Parameters
string$keyInput message key to be normalized
Returns
string Normalized message key

Definition at line 118 of file MessageCache.php.

Referenced by ApiQueryAllMessages\execute().

◆ parse()

MessageCache::parse (   $text,
  $title = null,
  $linestart = true,
  $interface = false,
  $language = null 
)
Parameters
string$text
Title | null$title
bool$linestartWhether or not this is at the start of a line
bool$interfaceWhether this is an interface message
Language | string | null$languageLanguage code
Returns
ParserOutput|string

Definition at line 1219 of file MessageCache.php.

References $res, $title, $wgTitle, Language\factory(), getParser(), getParserOptions(), Title\makeTitle(), NS_SPECIAL, wfDebugLog(), and wfGetAllCallers().

◆ refreshAndReplaceInternal()

MessageCache::refreshAndReplaceInternal (   $code,
array  $replacements 
)

◆ replace()

MessageCache::replace (   $title,
  $text 
)

Updates cache as necessary when message page is changed.

Parameters
string$titleMessage cache key with initial uppercase letter
string | bool$textNew contents of the page (false if deleted)

Definition at line 599 of file MessageCache.php.

References $title, $wgLanguageCode, DeferredUpdates\addUpdate(), figureMessage(), and DeferredUpdates\PRESEND.

Referenced by updateMessageOverride().

◆ saveToCaches()

MessageCache::saveToCaches ( array  $cache,
  $dest,
  $code = false 
)
protected

Shortcut to update caches.

Parameters
array$cacheCached messages with a version.
string$destEither "local-only" to save to local caches only or "all" to save to all caches.
string | bool$codeLanguage code (default: false)
Returns
bool

Definition at line 745 of file MessageCache.php.

References $success, saveToLocalCache(), and setValidationHash().

Referenced by load(), loadFromDBWithLock(), and refreshAndReplaceInternal().

◆ saveToLocalCache()

MessageCache::saveToLocalCache (   $code,
  $cache 
)
protected

Save the cache to APC.

Parameters
string$code
array$cacheThe cache array

Definition at line 202 of file MessageCache.php.

Referenced by saveToCaches().

◆ setValidationHash()

MessageCache::setValidationHash (   $code,
array  $cache 
)
protected

Set the md5 used to validate the local disk cache.

If $cache has a 'LATEST' UNIX timestamp key, then the hash will not be treated as "volatile" by getValidationHash() for the next few seconds. This is triggered when $cache is generated using FOR_UPDATE mode.

Parameters
string$code
array$cacheCached messages with a version

Definition at line 803 of file MessageCache.php.

References IExpiringStore\TTL_INDEFINITE.

Referenced by saveToCaches().

◆ singleton()

◆ transform()

MessageCache::transform (   $message,
  $interface = false,
  $language = null,
  $title = null 
)
Parameters
string$message
bool$interface
Language | null$language
Title | null$title
Returns
string

Definition at line 1162 of file MessageCache.php.

References $title, getParser(), and getParserOptions().

Referenced by EmailNotification\composeCommonMailtext().

◆ updateMessageOverride()

MessageCache::updateMessageOverride ( Title  $title,
Content  $content = null 
)

Purge message caches when a MediaWiki: page is created, updated, or deleted.

Parameters
Title$titleMessage page title
Content | null$contentNew content for edit/create, null on deletion
Since
1.29

Definition at line 1348 of file MessageCache.php.

References $content, Title\getDBkey(), getMessageTextFromContent(), and replace().

Member Data Documentation

◆ $cache

MapCacheLRU MessageCache::$cache
protected
Initial value:
=

Process cache of loaded messages that are defined in MediaWiki namespace.

Map of (language code => key => " <MESSAGE>" or "!TOO BIG" or "!ERROR")

Definition at line 48 of file MessageCache.php.

Referenced by load(), and loadFromDB().

◆ $cacheVolatile

bool [] MessageCache::$cacheVolatile = []
protected

Map of (language code => boolean)

Definition at line 71 of file MessageCache.php.

◆ $clusterCache

BagOStuff MessageCache::$clusterCache
protected

Definition at line 95 of file MessageCache.php.

Referenced by __construct().

◆ $contLang

Language MessageCache::$contLang
protected

Definition at line 99 of file MessageCache.php.

◆ $mDisable

bool MessageCache::$mDisable
protected

Should mean that database cannot be used, but check.

Definition at line 77 of file MessageCache.php.

Referenced by isDisabled().

◆ $mInParser

bool MessageCache::$mInParser = false
protected

Definition at line 90 of file MessageCache.php.

◆ $mParser

Parser MessageCache::$mParser
protected

Definition at line 85 of file MessageCache.php.

Referenced by getParser().

◆ $mParserOptions

ParserOptions MessageCache::$mParserOptions
protected

Message cache has its own parser which it uses to transform messages.

Definition at line 83 of file MessageCache.php.

Referenced by getParserOptions().

◆ $overridable

array MessageCache::$overridable
protected

Map of (lowercase message key => index) for all software defined messages.

Definition at line 66 of file MessageCache.php.

◆ $srvCache

BagOStuff MessageCache::$srvCache
protected

Definition at line 97 of file MessageCache.php.

◆ $wanCache

WANObjectCache MessageCache::$wanCache
protected

Definition at line 93 of file MessageCache.php.

Referenced by __construct().

◆ FOR_UPDATE

const MessageCache::FOR_UPDATE = 1

Definition at line 41 of file MessageCache.php.

◆ LOCK_TTL

const MessageCache::LOCK_TTL = 30

How long memcached locks last.

Definition at line 46 of file MessageCache.php.

◆ WAIT_SEC

const MessageCache::WAIT_SEC = 15

How long to wait for memcached locks.

Definition at line 44 of file MessageCache.php.


The documentation for this class was generated from the following file: