TYPO3 CMS  TYPO3_6-2
Public Member Functions | Public Attributes | Protected Member Functions | Protected Attributes | List of all members
TYPO3\CMS\Core\Cache\Backend\MemcachedBackend Class Reference
Inheritance diagram for TYPO3\CMS\Core\Cache\Backend\MemcachedBackend:
TYPO3\CMS\Core\Cache\Backend\AbstractBackend TYPO3\CMS\Core\Cache\Backend\TaggableBackendInterface TYPO3\CMS\Core\Cache\Backend\BackendInterface TYPO3\CMS\Core\Cache\Backend\BackendInterface t3lib_cache_backend_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 TYPO3\CMS\Core\Cache\Backend\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 TYPO3\CMS\Core\Cache\Backend\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 TYPO3\CMS\Core\Cache\Backend\AbstractBackend
 calculateExpiryTime ($lifetime=NULL)
 

Protected Attributes

 $memcache
 
 $servers = array()
 
 $flags
 
 $identifierPrefix
 
- Protected Attributes inherited from TYPO3\CMS\Core\Cache\Backend\AbstractBackend
 $cache
 
 $cacheIdentifier
 
 $context
 
 $defaultLifetime = 3600
 

Detailed Description

This file is part of the TYPO3 CMS project.

It is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License, either version 2 of the License, or any later version.

For the full copyright and license information, please read the LICENSE.txt file that was distributed with this source code.

The TYPO3 project - inspiring people to share! 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.

Author
Robert Lemke rober.nosp@m.t@ty.nosp@m.po3.o.nosp@m.rg
Christian Jul Jensen julle.nosp@m.@typ.nosp@m.o3.or.nosp@m.g
Karsten Dambekalns karst.nosp@m.en@t.nosp@m.ypo3..nosp@m.org
Dmitry Dulepov dmitr.nosp@m.y@ty.nosp@m.po3.o.nosp@m.rg

Definition at line 47 of file MemcachedBackend.php.

Constructor & Destructor Documentation

◆ __construct()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::__construct (   $context,
array  $options = array() 
)

Constructs this backend

Parameters
string$contextFLOW3's application context
array$optionsConfiguration options - depends on the actual backend
Exceptions

Definition at line 91 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\AbstractBackend\$context.

Member Function Documentation

◆ addIdentifierToTags()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::addIdentifierToTags (   $entryIdentifier,
array  $tags 
)
protected

Associates the identifier with the given tags

Parameters
string$entryIdentifier
array$tags
Returns
void

Definition at line 318 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\findIdentifiersByTag(), and TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\findTagsByIdentifier().

Referenced by TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\set().

◆ collectGarbage()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::collectGarbage ( )

Does nothing, as memcached does GC itself

Returns
void

Implements TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 393 of file MemcachedBackend.php.

◆ findIdentifiersByTag()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::findIdentifiersByTag (   $tag)

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

Parameters
string$tagThe tag to search for
Returns
array An array of entries with all matching entries. An empty array if no entries matched

Implements TYPO3\CMS\Core\Cache\Backend\TaggableBackendInterface.

Definition at line 274 of file MemcachedBackend.php.

Referenced by TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\addIdentifierToTags(), TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\flushByTag(), and TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\removeIdentifierFromAllTags().

◆ findTagsByIdentifier()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::findTagsByIdentifier (   $identifier)
protected

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

Parameters
string$identifierIdentifier to find tags by
Returns
array

Definition at line 382 of file MemcachedBackend.php.

Referenced by TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\addIdentifierToTags(), and TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\removeIdentifierFromAllTags().

◆ flush()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::flush ( )

Removes all cache entries of this cache.

Returns
void
Exceptions

Implements TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 290 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\flushByTag().

◆ flushByTag()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::flushByTag (   $tag)

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

Parameters
string$tagThe tag the entries must have
Returns
void

Implements TYPO3\CMS\Core\Cache\Backend\TaggableBackendInterface.

Definition at line 304 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\findIdentifiersByTag().

Referenced by TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\flush().

◆ get()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::get (   $entryIdentifier)

Loads data from the cache.

Parameters
string$entryIdentifierAn 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 TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 229 of file MemcachedBackend.php.

◆ has()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::has (   $entryIdentifier)

Checks if a cache entry with the specified identifier exists.

Parameters
string$entryIdentifierAn identifier specifying the cache entry
Returns
boolean TRUE if such an entry exists, FALSE if not

Implements TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 248 of file MemcachedBackend.php.

◆ initializeObject()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::initializeObject ( )

Initializes the identifier prefix

Returns
void
Exceptions

Definition at line 131 of file MemcachedBackend.php.

References $host.

◆ remove()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::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$entryIdentifierSpecifies the cache entry to remove
Returns
boolean TRUE if (at least) an entry could be removed or FALSE if no entry was found

Implements TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 261 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\removeIdentifierFromAllTags().

◆ removeIdentifierFromAllTags()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::removeIdentifierFromAllTags (   $entryIdentifier)
protected

Removes association of the identifier with the given tags

Parameters
string$entryIdentifier
arrayArray of tags
Returns
void

Definition at line 350 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\findIdentifiersByTag(), and TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\findTagsByIdentifier().

Referenced by TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\remove(), and TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\set().

◆ set()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::set (   $entryIdentifier,
  $data,
array  $tags = array(),
  $lifetime = NULL 
)

Saves data in the cache.

Parameters
string$entryIdentifierAn identifier for this specific cache entry
string$dataThe data to be stored
array$tagsTags to associate with this cache entry
integer$lifetimeLifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
Returns
void
Exceptions

Implements TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 181 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\AbstractBackend\$cacheIdentifier, TYPO3\CMS\Core\Cache\Backend\AbstractBackend\$defaultLifetime, $GLOBALS, TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\addIdentifierToTags(), TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\removeIdentifierFromAllTags(), and TYPO3\CMS\Core\Utility\GeneralUtility\SYSLOG_SEVERITY_WARNING.

◆ setCache()

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

Initializes the identifier prefix when setting the cache.

Parameters
\TYPO3\CMS\Core\Cache\Frontend\FrontendInterface$cacheThe frontend for this backend
Returns
void

Implements TYPO3\CMS\Core\Cache\Backend\BackendInterface.

Definition at line 162 of file MemcachedBackend.php.

◆ setCompression()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::setCompression (   $useCompression)
protected

Setter for compression flags bit

Parameters
boolean$useCompression
Returns
void

Definition at line 117 of file MemcachedBackend.php.

◆ setServers()

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::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$serversAn array of servers to add.
Returns
void

Definition at line 106 of file MemcachedBackend.php.

References TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\$servers.

Member Data Documentation

◆ $flags

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::$flags
protected

Definition at line 75 of file MemcachedBackend.php.

◆ $identifierPrefix

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::$identifierPrefix
protected

Definition at line 82 of file MemcachedBackend.php.

◆ $memcache

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::$memcache
protected

Definition at line 60 of file MemcachedBackend.php.

◆ $servers

TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::$servers = array()
protected

Definition at line 67 of file MemcachedBackend.php.

Referenced by TYPO3\CMS\Core\Cache\Backend\MemcachedBackend\setServers().

◆ MAX_BUCKET_SIZE

const TYPO3\CMS\Core\Cache\Backend\MemcachedBackend::MAX_BUCKET_SIZE = 1048534

Definition at line 54 of file MemcachedBackend.php.