MediaWiki  REL1_31
MessageCache Class Reference

Message cache Performs various MediaWiki namespace-related functions. More...

Collaboration diagram for MessageCache:

Public Member Functions

 __construct (WANObjectCache $wanCache, BagOStuff $clusterCache, BagOStuff $serverCache, $useDB, $expiry)
 
 clear ()
 Clear all stored messages in global and local cache. More...
 
 disable ()
 
 enable ()
 
 figureMessage ( $key)
 
 get ( $key, $useDB=true, $langcode=true, $isFullKey=false)
 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)
 
 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 destroyInstance ()
 Destroy the singleton instance. More...
 
static normalizeKey ( $key)
 Normalize message key input. More...
 
static singleton ()
 Get the signleton 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

BagOStuff $clusterCache
 
 $mCache
 Process local cache of loaded messages that are defined in MediaWiki namespace. More...
 
bool[] $mCacheVolatile = []
 Map of (language code => boolean) More...
 
 $mDisable
 Should mean that database cannot be used, but check. More...
 
 $mExpiry
 Lifetime for cache, used by object caching. More...
 
 $mInParser = false
 
 $mLoadedLanguages = []
 Variable for tracking which variables are already loaded. More...
 
Parser $mParser
 
ParserOptions $mParserOptions
 Message cache has its own parser which it uses to transform 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)
 

Static Private Attributes

static $instance
 Singleton instance. More...
 

Detailed Description

Message cache Performs various MediaWiki namespace-related functions.

Definition at line 39 of file MessageCache.php.

Constructor & Destructor Documentation

◆ __construct()

MessageCache::__construct ( WANObjectCache  $wanCache,
BagOStuff  $clusterCache,
BagOStuff  $serverCache,
  $useDB,
  $expiry 
)
Parameters
WANObjectCache$wanCache
BagOStuff$clusterCache
BagOStuff$serverCache
bool$useDBWhether to look for message overrides (e.g. MediaWiki: pages)
int$expiryLifetime for cache.
See also
$mExpiry.

Definition at line 165 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 1315 of file MessageCache.php.

References $title.

Referenced by getMsgFromNamespace(), and replace().

◆ clear()

MessageCache::clear ( )

Clear all stored messages in global and local cache.

Mainly used after a mass rebuild

Definition at line 1193 of file MessageCache.php.

References $code, as, Language\fetchLanguageNames(), and getCheckKey().

◆ destroyInstance()

static MessageCache::destroyInstance ( )
static

Destroy the singleton instance.

Since
1.18

Definition at line 135 of file MessageCache.php.

Referenced by ParserTestRunner\staticSetup(), and MessageTest\testRawHtmlInMsg().

◆ disable()

MessageCache::disable ( )

Definition at line 1164 of file MessageCache.php.

◆ enable()

MessageCache::enable ( )

Definition at line 1168 of file MessageCache.php.

◆ figureMessage()

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

Definition at line 1206 of file MessageCache.php.

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

Referenced by replace().

◆ get()

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

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$langcodeCode of the language to get the message for.
  • If string and a valid code, will create a standard language object
  • If string but not a valid code, will create a basic language object
  • If boolean and false, create object from the current users language
  • If boolean and true, create object from the wikis content language
  • If language object, use it as given
bool$isFullKeySpecifies whether $key is a two part key "msg/lang".
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 779 of file MessageCache.php.

References $lang, by, Language\getMessageFor(), getMessageFromFallbackChain(), normalizeKey(), Hooks\run(), string, 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 1232 of file MessageCache.php.

References $cache, $code, $wgContLang, global, 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 1278 of file MessageCache.php.

References $code.

Referenced by clear(), and replace().

◆ getLocalCache()

MessageCache::getLocalCache (   $code)
protected

Try to load the cache from APC.

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

Definition at line 214 of file MessageCache.php.

References $code.

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$useDBWhether to include messages from the wiki database
bool[]$alreadyTriedContains true for each language that has been tried already
Returns
string|bool The message, or false if not found

Definition at line 888 of file MessageCache.php.

References $code, $lang, $wgContLang, as, Language\getFallbacksFor(), getMessagePageName(), getMsgFromNamespace(), and global.

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 862 of file MessageCache.php.

References $lang, $wgContLang, getMessageForLang(), and global.

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 947 of file MessageCache.php.

References $wgLanguageCode, and global.

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 1286 of file MessageCache.php.

Referenced by getMsgFromNamespace(), replace(), 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 970 of file MessageCache.php.

References $code, $dbr, $title, bigMessageCacheKey(), DB_REPLICA, getMessageTextFromContent(), load(), Title\makeTitle(), Revision\newKnownCurrent(), NS_MEDIAWIKI, Hooks\run(), and wfGetDB().

Referenced by getMessageForLang().

◆ getParser()

MessageCache::getParser ( )
Returns
Parser

Definition at line 1100 of file MessageCache.php.

References $mParser, $wgParser, $wgParserConf, class, and global.

Referenced by parse(), and transform().

◆ getParserOptions()

MessageCache::getParserOptions ( )

ParserOptions is lazy initialised.

Returns
ParserOptions

Definition at line 185 of file MessageCache.php.

References $mParserOptions, $wgUser, global, ParserOptions\newFromAnon(), and ParserOptions\setAllowUnsafeRawHtml().

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 741 of file MessageCache.php.

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

◆ 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 687 of file MessageCache.php.

References $code, $value, 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 644 of file MessageCache.php.

References $cache, 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 1184 of file MessageCache.php.

References $mDisable.

◆ 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 succesfully 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 succesfully populated, or false if populating empty cache fails. Also returns true if MessageCache is disabled.

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

Definition at line 252 of file MessageCache.php.

References $cache, $code, $success, array(), cache, data, getLocalCache(), getReentrantScopedLock(), getValidationHash(), isCacheExpired(), list, loadFromDBWithLock(), of, or, saveToCaches(), too, wfDebug(), and wfDebugLog().

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

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

Definition at line 456 of file MessageCache.php.

References $cache, $code, $dbr, $res, $value, $wgAdaptiveMessageCache, $wgLanguageCode, $wgMaxMsgCacheEntrySize, as, DB_MASTER, DB_REPLICA, Revision\getRevisionText(), global, load(), MSG_CACHE_VERSION, NS_MEDIAWIKI, serialize(), wfDebugLog(), wfGetDB(), and wfTimestamp().

Referenced by loadFromDBWithLock(), and replace().

◆ loadFromDBWithLock()

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

Definition at line 394 of file MessageCache.php.

References $cache, $code, 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 145 of file MessageCache.php.

References $wgContLang, and global.

Referenced by ApiQueryAllMessages\execute(), get(), and MessageCacheTest\testNormalizeKey().

◆ parse()

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

Definition at line 1127 of file MessageCache.php.

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

◆ 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 564 of file MessageCache.php.

References $cache, $code, $title, $wgContLang, $wgLanguageCode, $wgMaxMsgCacheEntrySize, DeferredUpdates\addCallableUpdate(), bigMessageCacheKey(), WikiPage\factory(), figureMessage(), getCheckKey(), RequestContext\getMain(), getMessageTextFromContent(), getReentrantScopedLock(), global, list, loadFromDB(), Title\makeTitle(), NS_MEDIAWIKI, DeferredUpdates\PRESEND, Hooks\run(), saveToCaches(), and use.

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 667 of file MessageCache.php.

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

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

◆ saveToLocalCache()

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

Save the cache to APC.

Parameters
string$code
array$cacheThe cache array

Definition at line 226 of file MessageCache.php.

References $cache, and $code.

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 725 of file MessageCache.php.

References $cache, $code, and IExpiringStore\TTL_INDEFINITE.

Referenced by saveToCaches().

◆ singleton()

◆ transform()

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

Definition at line 1071 of file MessageCache.php.

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

◆ 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 1259 of file MessageCache.php.

References $title, $wgContLang, Title\getDBkey(), getMessageTextFromContent(), global, and replace().

Member Data Documentation

◆ $clusterCache

BagOStuff MessageCache::$clusterCache
protected

Definition at line 96 of file MessageCache.php.

Referenced by __construct().

◆ $instance

MessageCache MessageCache::$instance
staticprivate

Singleton instance.

Definition at line 105 of file MessageCache.php.

Referenced by singleton().

◆ $mCache

array MessageCache::$mCache
protected

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

First array level is a language code, second level is message key and the values are either message content prefixed with space, or !NONEXISTENT for negative caching.

Definition at line 55 of file MessageCache.php.

◆ $mCacheVolatile

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

Map of (language code => boolean)

Definition at line 60 of file MessageCache.php.

◆ $mDisable

bool MessageCache::$mDisable
protected

Should mean that database cannot be used, but check.

Definition at line 66 of file MessageCache.php.

Referenced by isDisabled().

◆ $mExpiry

MessageCache::$mExpiry
protected

Lifetime for cache, used by object caching.

Set on construction, see __construct().

Definition at line 72 of file MessageCache.php.

◆ $mInParser

bool MessageCache::$mInParser = false
protected

Definition at line 91 of file MessageCache.php.

◆ $mLoadedLanguages

array MessageCache::$mLoadedLanguages = []
protected

Variable for tracking which variables are already loaded.

Definition at line 86 of file MessageCache.php.

◆ $mParser

Parser MessageCache::$mParser
protected

Definition at line 80 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 78 of file MessageCache.php.

Referenced by getParserOptions().

◆ $srvCache

BagOStuff MessageCache::$srvCache
protected

Definition at line 98 of file MessageCache.php.

◆ $wanCache

WANObjectCache MessageCache::$wanCache
protected

Definition at line 94 of file MessageCache.php.

Referenced by __construct().

◆ FOR_UPDATE

const MessageCache::FOR_UPDATE = 1

Definition at line 40 of file MessageCache.php.

◆ LOCK_TTL

const MessageCache::LOCK_TTL = 30

How long memcached locks last.

Definition at line 45 of file MessageCache.php.

◆ WAIT_SEC

const MessageCache::WAIT_SEC = 15

How long to wait for memcached locks.

Definition at line 43 of file MessageCache.php.


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