CacheBackendInterface.php in Drupal 8
Same filename and directory in other branches
Namespace
Drupal\Core\CacheFile
core/lib/Drupal/Core/Cache/CacheBackendInterface.phpView source
<?php
namespace Drupal\Core\Cache;
/**
* Defines an interface for cache implementations.
*
* All cache implementations have to implement this interface.
* Drupal\Core\Cache\DatabaseBackend provides the default implementation, which
* can be consulted as an example.
*
* The cache identifiers are case sensitive.
*
* @ingroup cache
*/
interface CacheBackendInterface {
/**
* Indicates that the item should never be removed unless explicitly deleted.
*/
const CACHE_PERMANENT = -1;
/**
* Returns data from the persistent cache.
*
* @param string $cid
* The cache ID of the data to retrieve.
* @param bool $allow_invalid
* (optional) If TRUE, a cache item may be returned even if it is expired or
* has been invalidated. Such items may sometimes be preferred, if the
* alternative is recalculating the value stored in the cache, especially
* if another concurrent request is already recalculating the same value.
* The "valid" property of the returned object indicates whether the item is
* valid or not. Defaults to FALSE.
*
* @return object|false
* The cache item or FALSE on failure.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::getMultiple()
*/
public function get($cid, $allow_invalid = FALSE);
/**
* Returns data from the persistent cache when given an array of cache IDs.
*
* @param array $cids
* An array of cache IDs for the data to retrieve. This is passed by
* reference, and will have the IDs successfully returned from cache
* removed.
* @param bool $allow_invalid
* (optional) If TRUE, cache items may be returned even if they have expired
* or been invalidated. Such items may sometimes be preferred, if the
* alternative is recalculating the value stored in the cache, especially
* if another concurrent thread is already recalculating the same value. The
* "valid" property of the returned objects indicates whether the items are
* valid or not. Defaults to FALSE.
*
* @return array
* An array of cache item objects indexed by cache ID.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::get()
*/
public function getMultiple(&$cids, $allow_invalid = FALSE);
/**
* Stores data in the persistent cache.
*
* Core cache implementations set the created time on cache item with
* microtime(TRUE) rather than REQUEST_TIME_FLOAT, because the created time
* of cache items should match when they are created, not when the request
* started. Apart from being more accurate, this increases the chance an
* item will legitimately be considered valid.
*
* @param string $cid
* The cache ID of the data to store.
* @param mixed $data
* The data to store in the cache.
* Some storage engines only allow objects up to a maximum of 1MB in size to
* be stored by default. When caching large arrays or similar, take care to
* ensure $data does not exceed this size.
* @param int $expire
* One of the following values:
* - CacheBackendInterface::CACHE_PERMANENT: Indicates that the item should
* not be removed unless it is deleted explicitly.
* - A Unix timestamp: Indicates that the item will be considered invalid
* after this time, i.e. it will not be returned by get() unless
* $allow_invalid has been set to TRUE. When the item has expired, it may
* be permanently deleted by the garbage collector at any time.
* @param array $tags
* An array of tags to be stored with the cache item. These should normally
* identify objects used to build the cache item, which should trigger
* cache invalidation when updated. For example if a cached item represents
* a node, both the node ID and the author's user ID might be passed in as
* tags. For example ['node:123', 'node:456', 'user:789'].
*
* @see \Drupal\Core\Cache\CacheBackendInterface::get()
* @see \Drupal\Core\Cache\CacheBackendInterface::getMultiple()
*/
public function set($cid, $data, $expire = Cache::PERMANENT, array $tags = []);
/**
* Store multiple items in the persistent cache.
*
* @param array $items
* An array of cache items, keyed by cid. In the form:
* @code
* $items = array(
* $cid => array(
* // Required, will be automatically serialized if not a string.
* 'data' => $data,
* // Optional, defaults to CacheBackendInterface::CACHE_PERMANENT.
* 'expire' => CacheBackendInterface::CACHE_PERMANENT,
* // (optional) The cache tags for this item, see CacheBackendInterface::set().
* 'tags' => array(),
* ),
* );
* @endcode
*/
public function setMultiple(array $items);
/**
* Deletes an item from the cache.
*
* If the cache item is being deleted because it is no longer "fresh", you may
* consider using invalidate() instead. This allows callers to retrieve the
* invalid item by calling get() with $allow_invalid set to TRUE. In some cases
* an invalid item may be acceptable rather than having to rebuild the cache.
*
* @param string $cid
* The cache ID to delete.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidate()
* @see \Drupal\Core\Cache\CacheBackendInterface::deleteMultiple()
* @see \Drupal\Core\Cache\CacheBackendInterface::deleteAll()
*/
public function delete($cid);
/**
* Deletes multiple items from the cache.
*
* If the cache items are being deleted because they are no longer "fresh",
* you may consider using invalidateMultiple() instead. This allows callers to
* retrieve the invalid items by calling get() with $allow_invalid set to TRUE.
* In some cases an invalid item may be acceptable rather than having to
* rebuild the cache.
*
* @param array $cids
* An array of cache IDs to delete.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidateMultiple()
* @see \Drupal\Core\Cache\CacheBackendInterface::delete()
* @see \Drupal\Core\Cache\CacheBackendInterface::deleteAll()
*/
public function deleteMultiple(array $cids);
/**
* Deletes all cache items in a bin.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidateAll()
* @see \Drupal\Core\Cache\CacheBackendInterface::delete()
* @see \Drupal\Core\Cache\CacheBackendInterface::deleteMultiple()
*/
public function deleteAll();
/**
* Marks a cache item as invalid.
*
* Invalid items may be returned in later calls to get(), if the $allow_invalid
* argument is TRUE.
*
* @param string $cid
* The cache ID to invalidate.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::delete()
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidateMultiple()
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidateAll()
*/
public function invalidate($cid);
/**
* Marks cache items as invalid.
*
* Invalid items may be returned in later calls to get(), if the $allow_invalid
* argument is TRUE.
*
* @param string[] $cids
* An array of cache IDs to invalidate.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::deleteMultiple()
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidate()
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidateAll()
*/
public function invalidateMultiple(array $cids);
/**
* Marks all cache items as invalid.
*
* Invalid items may be returned in later calls to get(), if the $allow_invalid
* argument is TRUE.
*
* @see \Drupal\Core\Cache\CacheBackendInterface::deleteAll()
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidate()
* @see \Drupal\Core\Cache\CacheBackendInterface::invalidateMultiple()
*/
public function invalidateAll();
/**
* Performs garbage collection on a cache bin.
*
* The backend may choose to delete expired or invalidated items.
*/
public function garbageCollection();
/**
* Remove a cache bin.
*/
public function removeBin();
}
Interfaces
Name | Description |
---|---|
CacheBackendInterface | Defines an interface for cache implementations. |