Inheritance diagram for MemcachedBackend:

Public Member Functions
	__construct ($context, array $options=array())

	initializeObject ()

	setCache (\TYPO3\CMS\Core\Cache\Frontend\FrontendInterface $cache)

	set ($entryIdentifier, $data, array $tags=array(), $lifetime=null)

	get ($entryIdentifier)

	has ($entryIdentifier)

	remove ($entryIdentifier)

	findIdentifiersByTag ($tag)

	flush ()

	flushByTag ($tag)

	collectGarbage ()

Public Member Functions inherited from AbstractBackend
	__construct ($context, array $options=array())

	setCache (\TYPO3\CMS\Core\Cache\Frontend\FrontendInterface $cache)

	setDefaultLifetime ($defaultLifetime)

Public Attributes
const	MAX_BUCKET_SIZE = 1048534

Public Attributes inherited from AbstractBackend
const	DATETIME_EXPIRYTIME_UNLIMITED = '9999-12-31T23:59:59+0000'

const	UNLIMITED_LIFETIME = 0

Protected Member Functions
	setServers (array $servers)

	setCompression ($useCompression)

	addIdentifierToTags ($entryIdentifier, array $tags)

	removeIdentifierFromAllTags ($entryIdentifier)

	findTagsByIdentifier ($identifier)

Protected Member Functions inherited from AbstractBackend
	calculateExpiryTime ($lifetime=null)

Protected Attributes
	$memcache

	$servers = array()

	$flags

	$identifierPrefix

Protected Attributes inherited from AbstractBackend
	$cache

	$cacheIdentifier

	$context

	$defaultLifetime = 3600

Detailed Description

A caching backend which stores cache entries by using Memcached.

This backend uses the following types of Memcache keys:

tag_xxx xxx is tag name, value is array of associated identifiers identifier. This is "forward" tag index. It is mainly used for obtaining content by tag (get identifier by tag -> get content by identifier)
ident_xxx xxx is identifier, value is array of associated tags. This is "reverse" tag index. It provides quick access for all tags associated with this identifier and used when removing the identifier

Each key is prepended with a prefix. By default prefix consists from two parts separated by underscore character and ends in yet another underscore character:

"TYPO3"
Current site path obtained from the PATH_site constant This prefix makes sure that keys from the different installations do not conflict.

Note: When using the Memcached backend to store values of more than ~1 MB, the data will be split into chunks to make them fit into the memcached limits.

This file is a backport from FLOW3 by Ingo Renner.

Definition at line 43 of file MemcachedBackend.php.

Constructor & Destructor Documentation

__construct	(		$context,
		array	$options = `array()`
	)

Constructs this backend

Parameters

string	$context	FLOW3's application context
array	$options	Configuration options - depends on the actual backend

Exceptions

\TYPO3\CMS\Core\Cache\Exception if memcache is not installed

Definition at line 87 of file MemcachedBackend.php.

References AbstractBackend\$context.

Member Function Documentation

addIdentifierToTags	(		$entryIdentifier,
		array	$tags
	)

protected

Associates the identifier with the given tags

Parameters

string	$entryIdentifier
array	$tags

Returns: void

Definition at line 326 of file MemcachedBackend.php.

References MemcachedBackend\findIdentifiersByTag(), and MemcachedBackend\findTagsByIdentifier().

Referenced by MemcachedBackend\set().

collectGarbage ( )

Does nothing, as memcached does GC itself

Returns: void

Implements BackendInterface.

Definition at line 404 of file MemcachedBackend.php.

findIdentifiersByTag ( $tag )

Finds and returns all cache entry identifiers which are tagged by the specified tag.

Parameters

string $tag The tag to search for

Returns: array An array of entries with all matching entries. An empty array if no entries matched

Implements TaggableBackendInterface.

Definition at line 279 of file MemcachedBackend.php.

Referenced by MemcachedBackend\addIdentifierToTags(), MemcachedBackend\flushByTag(), and MemcachedBackend\removeIdentifierFromAllTags().

findTagsByIdentifier ( $identifier )

protected

Finds all tags for the given identifier. This function uses reverse tag index to search for tags.

Parameters

string $identifier Identifier to find tags by

Returns: array

Definition at line 392 of file MemcachedBackend.php.

Referenced by MemcachedBackend\addIdentifierToTags(), and MemcachedBackend\removeIdentifierFromAllTags().

flush ( )

Removes all cache entries of this cache.

Returns: void

Exceptions

\TYPO3\CMS\Core\Cache\Exception

Implements BackendInterface.

Definition at line 296 of file MemcachedBackend.php.

References MemcachedBackend\flushByTag().

flushByTag ( $tag )

Removes all cache entries of this cache which are tagged by the specified tag.

Parameters

string $tag The tag the entries must have

Returns: void

Implements TaggableBackendInterface.

Definition at line 311 of file MemcachedBackend.php.

References MemcachedBackend\findIdentifiersByTag().

Referenced by MemcachedBackend\flush().

get ( $entryIdentifier )

Loads data from the cache.

Parameters

string $entryIdentifier An identifier which describes the cache entry to load

Returns: mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded

Implements BackendInterface.

Definition at line 231 of file MemcachedBackend.php.

has ( $entryIdentifier )

Checks if a cache entry with the specified identifier exists.

Parameters

string $entryIdentifier An identifier specifying the cache entry

Returns: bool TRUE if such an entry exists, FALSE if not

Implements BackendInterface.

Definition at line 251 of file MemcachedBackend.php.

initializeObject ( )

Initializes the identifier prefix

Returns: void

Exceptions

\TYPO3\CMS\Core\Cache\Exception

Definition at line 130 of file MemcachedBackend.php.

References $server.

remove ( $entryIdentifier )

Removes all cache entries matching the specified identifier. Usually this only affects one entry but if - for what reason ever - old entries for the identifier still exist, they are removed as well.

Parameters

string $entryIdentifier Specifies the cache entry to remove

Returns: bool TRUE if (at least) an entry could be removed or FALSE if no entry was found

Implements BackendInterface.

Definition at line 265 of file MemcachedBackend.php.

References MemcachedBackend\removeIdentifierFromAllTags().

removeIdentifierFromAllTags ( $entryIdentifier )

protected

Removes association of the identifier with the given tags

Parameters

string	$entryIdentifier
	array	Array of tags

Returns: void

Definition at line 359 of file MemcachedBackend.php.

References MemcachedBackend\findIdentifiersByTag(), and MemcachedBackend\findTagsByIdentifier().

Referenced by MemcachedBackend\remove(), and MemcachedBackend\set().

set	(		$entryIdentifier,
			$data,
		array	$tags = `array()`,
			$lifetime = `null`
	)

Saves data in the cache.

Parameters

string	$entryIdentifier	An identifier for this specific cache entry
string	$data	The data to be stored
array	$tags	Tags to associate with this cache entry
int	$lifetime	Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.

Returns: void

Exceptions

\TYPO3\CMS\Core\Cache\Exception	if no cache frontend has been set.
\InvalidArgumentException	if the identifier is not valid or the final memcached key is longer than 250 characters
\TYPO3\CMS\Core\Cache\Exception\InvalidDataException	if $data is not a string

Implements BackendInterface.

Definition at line 182 of file MemcachedBackend.php.

References AbstractBackend\$cacheIdentifier, AbstractBackend\$defaultLifetime, $GLOBALS, MemcachedBackend\addIdentifierToTags(), and MemcachedBackend\removeIdentifierFromAllTags().

setCache ( \TYPO3\CMS\Core\Cache\Frontend\FrontendInterface $cache )

Initializes the identifier prefix when setting the cache.

Parameters

\TYPO3\CMS\Core\Cache\Frontend\FrontendInterface $cache The frontend for this backend

Returns: void

Implements BackendInterface.

Definition at line 162 of file MemcachedBackend.php.

setCompression ( $useCompression )

protected

Setter for compression flags bit

Parameters

bool $useCompression

Returns: void

Definition at line 115 of file MemcachedBackend.php.

setServers ( array $servers )

protected

Setter for servers to be used. Expects an array, the values are expected to be formatted like "<host>[:<port>]" or "unix://<path>"

Parameters

array $servers An array of servers to add.

Returns: void

Definition at line 103 of file MemcachedBackend.php.

References MemcachedBackend\$servers.

Member Data Documentation

$flags

protected

Definition at line 71 of file MemcachedBackend.php.

$identifierPrefix

protected

Definition at line 78 of file MemcachedBackend.php.

$memcache

protected

Definition at line 56 of file MemcachedBackend.php.

$servers = array()

protected

Definition at line 63 of file MemcachedBackend.php.

Referenced by MemcachedBackend\setServers().

const MAX_BUCKET_SIZE = 1048534

Definition at line 50 of file MemcachedBackend.php.

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation