1. class
  2. Drupal
  3. \
  4. Core
  5. \
  6. Cache
  7. \
  8. PhpBackend

PhpBackend

class PhpBackend implements CacheBackendInterface (View source)

Defines a PHP cache implementation.

Stores cache items in a PHP file using a storage that implements Drupal\Component\PhpStorage\PhpStorageInterface.

This is fast because of PHP's opcode caching mechanism. Once a file's content is stored in PHP's opcode cache, including it doesn't require reading the contents from a filesystem. Instead, PHP will use the already compiled opcodes stored in memory.

Properties

protected string $bin
protected $cache

Array to store cache objects.
protected CacheTagsChecksumInterface $checksumProvider

The cache tags checksum provider.

Methods

__construct(string $bin, CacheTagsChecksumInterface $checksum_provider)

Constructs a PhpBackend object.

object|false
get(string $cid, bool $allow_invalid = FALSE)

Returns data from the persistent cache.

bool|mixed
getByHash(string $cidhash, bool $allow_invalid = FALSE)

Fetch a cache item using a hashed cache ID.

setMultiple(array $items)

Store multiple items in the persistent cache.

array
getMultiple(array $cids, bool $allow_invalid = FALSE)

Returns data from the persistent cache when given an array of cache IDs.

mixed
prepareItem(object $cache, bool $allow_invalid)

Prepares a cached item.

set(string $cid, mixed $data, int $expire = Cache::PERMANENT, array $tags = [])

Stores data in the persistent cache.

delete(string $cid)

Deletes an item from the cache.

deleteMultiple(array $cids)

Deletes multiple items from the cache.

deleteAll()

Deletes all cache items in a bin.

invalidate(string $cid)

Marks a cache item as invalid.

invalidatebyHash(string $cidhash)

Invalidate one cache item.

invalidateMultiple(array $cids)

Marks cache items as invalid.

invalidateAll()

Marks all cache items as invalid.

garbageCollection()

Performs garbage collection on a cache bin.

removeBin()

Remove a cache bin.

writeItem(string $cidhash, stdClass $item)

Writes a cache item to PhpStorage.

PhpStorageInterface
storage()

Gets the PHP code storage object to use.

string
normalizeCid(string $cid)

Ensures a normalized cache ID.

Details

at line 49
__construct(string $bin, CacheTagsChecksumInterface $checksum_provider)

Constructs a PhpBackend object.

Parameters

string $bin

The cache bin for which the object is created.
CacheTagsChecksumInterface $checksum_provider

The cache tags checksum provider.

at line 57
object|false get(string $cid, bool $allow_invalid = FALSE)

Returns data from the persistent cache.

Parameters

string $cid

The cache ID of the data to retrieve.
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 Value

object|false

The cache item or FALSE on failure.

at line 72
protected bool|mixed getByHash(string $cidhash, bool $allow_invalid = FALSE)

Fetch a cache item using a hashed cache ID.

Parameters

string $cidhash

The hashed version of the original cache ID after being normalized.
bool $allow_invalid

(optional) If TRUE, a cache item may be returned even if it is expired or has been invalidated.

Return Value

bool|mixed

at line 85
setMultiple(array $items)

Store multiple items in the persistent cache.

Parameters

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

at line 94
array getMultiple(array $cids, bool $allow_invalid = FALSE)

Returns data from the persistent cache when given an array of cache IDs.

Parameters

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.
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 Value

array

An array of cache item objects indexed by cache ID.

at line 123
protected mixed prepareItem(object $cache, bool $allow_invalid)

Prepares a cached item.

Checks that items are either permanent or did not expire, and returns data as appropriate.

Parameters

object $cache

An item loaded from self::get() or self::getMultiple().
bool $allow_invalid

If FALSE, the method returns FALSE if the cache item is not valid.

Return Value

mixed

The item with data as appropriate or FALSE if there is no valid item to load.

at line 146
set(string $cid, mixed $data, int $expire = Cache::PERMANENT, array $tags = [])

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.

Parameters

string $cid

The cache ID of the data to store.
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.
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.
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'].

at line 163
delete(string $cid)

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.

Parameters

string $cid

The cache ID to delete.

at line 170
deleteMultiple(array $cids)

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.

Parameters

array $cids

An array of cache IDs to delete.

at line 179
deleteAll()

Deletes all cache items in a bin.

at line 186
invalidate(string $cid)

Marks a cache item as invalid.

Invalid items may be returned in later calls to get(), if the $allow_invalid argument is TRUE.

Parameters

string $cid

The cache ID to invalidate.

at line 196
protected invalidatebyHash(string $cidhash)

Invalidate one cache item.

Parameters

string $cidhash

The hashed version of the original cache ID after being normalized.

at line 206
invalidateMultiple(array $cids)

Marks cache items as invalid.

Invalid items may be returned in later calls to get(), if the $allow_invalid argument is TRUE.

Parameters

array $cids

An array of cache IDs to invalidate.

at line 215
invalidateAll()

Marks all cache items as invalid.

Invalid items may be returned in later calls to get(), if the $allow_invalid argument is TRUE.

at line 224
garbageCollection()

Performs garbage collection on a cache bin.

The backend may choose to delete expired or invalidated items.

at line 230
removeBin()

Remove a cache bin.

at line 243
protected writeItem(string $cidhash, stdClass $item)

Writes a cache item to PhpStorage.

Parameters

string $cidhash

The hashed version of the original cache ID after being normalized.
stdClass $item

The cache item to store.

at line 253
protected PhpStorageInterface storage()

Gets the PHP code storage object to use.

Return Value

PhpStorageInterface

at line 269
protected string normalizeCid(string $cid)

Ensures a normalized cache ID.

Parameters

string $cid

The passed in cache ID.

Return Value

string

A normalized cache ID.