APCUBagOStuff Class Reference

This is a wrapper for APCU's shared memory functions. More...

Inheritance diagram for APCUBagOStuff:

Collaboration diagram for APCUBagOStuff:

Public Member Functions
	__construct (array $params=[])
	decr ( $key, $value=1, $flags=0)
	Decrease stored value of $key by $value while preserving its TTL.
	incr ( $key, $value=1, $flags=0)
	Increase stored value of $key by $value while preserving its TTL.
	incrWithInit ( $key, $exptime, $value=1, $init=null, $flags=0)
	Increase the value of the given key (no TTL change) if it exists or create it otherwise.
Public Member Functions inherited from MediumSpecificBagOStuff
	add ( $key, $value, $exptime=0, $flags=0)
	Insert an item if it does not already exist.
	addBusyCallback (callable $workCallback)
	Let a callback be run to avoid wasting time on special blocking calls.
	changeTTL ( $key, $exptime=0, $flags=0)
	Change the expiration on a key if it exists.
	changeTTLMulti (array $keys, $exptime, $flags=0)
	Change the expiration of multiple keys that exist.
	clearLastError ()
	Clear the "last error" registry.
	delete ( $key, $flags=0)
	Delete an item.
	deleteMulti (array $keys, $flags=0)
	Batch deletion.
	deleteObjectsExpiringBefore ( $timestamp, callable $progress=null, $limit=INF)
	Delete all objects expiring before a certain date.
	get ( $key, $flags=0)
	Get an item with the given key.
	getLastError ()
	Get the "last error" registered; clearLastError() should be called manually.
	getMulti (array $keys, $flags=0)
	Get an associative array containing the item for each of the keys that have items.
	getQoS ( $flag)
	getSegmentationSize ()
	getSegmentedValueMaxSize ()
	lock ( $key, $timeout=6, $expiry=6, $rclass='')
	Acquire an advisory lock on a key string.
	makeGlobalKey ( $class,... $components)
	Make a global cache key.
	makeKey ( $class,... $components)
	Make a cache key, scoped to this instance's keyspace.
	makeKeyInternal ( $keyspace, $args)
	Construct a cache key.
	merge ( $key, callable $callback, $exptime=0, $attempts=10, $flags=0)
	Merge changes into the existing cache value (possibly creating a new one)
	set ( $key, $value, $exptime=0, $flags=0)
	Set an item.
	setMulti (array $data, $exptime=0, $flags=0)
	Batch insertion/replace.
	setNewPreparedValues (array $valueByKey)
	Prepare values for storage and get their serialized sizes, or, estimate those sizes.
	unlock ( $key)
	Release an advisory lock on a key string.
Public Member Functions inherited from BagOStuff
	getCurrentTime ()
	getLogger ()
	getScopedLock ( $key, $timeout=6, $expiry=30, $rclass='')
	Get a lightweight exclusive self-unlocking lock.
	getWithSetCallback ( $key, $exptime, $callback, $flags=0)
	Get an item with the given key, regenerating and setting it if not found.
	setDebug ( $enabled)
	setLogger (LoggerInterface $logger)
	setMockTime (&$time)

Protected Member Functions
	doAdd ( $key, $value, $exptime=0, $flags=0)
	Insert an item if it does not already exist.
	doDelete ( $key, $flags=0)
	Delete an item.
	doGet ( $key, $flags=0, &$casToken=null)
	doSet ( $key, $value, $exptime=0, $flags=0)
	Set an item.
Protected Member Functions inherited from MediumSpecificBagOStuff
	cas ( $casToken, $key, $value, $exptime=0, $flags=0)
	Check and set an item.
	debug ( $text)
	doCas ( $casToken, $key, $value, $exptime=0, $flags=0)
	Check and set an item.
	doChangeTTL ( $key, $exptime, $flags)
	doDeleteMulti (array $keys, $flags=0)
	doGetMulti (array $keys, $flags=0)
	Get an associative array containing the item for each of the keys that have items.
	doSetMulti (array $data, $exptime=0, $flags=0)
	getExpirationAsTimestamp ( $exptime)
	Convert an optionally relative timestamp to an absolute time.
	getExpirationAsTTL ( $exptime)
	Convert an optionally absolute expiry time to a relative time.
	getSerialized ( $value, $key)
	Get the serialized form a value, using any applicable prepared value.
	guessSerialValueSize ( $value, $depth=0, &$loops=0)
	Estimate the size of a variable once serialized.
	isInteger ( $value)
	Check if a value is an integer.
	isRelativeExpiration ( $exptime)
	makeValueOrSegmentList ( $key, $value, $exptime, $flags)
	Determine the entry (inline or segment list) to store under a key to save the value.
	mergeViaCas ( $key, callable $callback, $exptime, $attempts, $flags)
	resolveSegments ( $key, $mainValue)
	Get and reassemble the chunks of blob at the given key.
	serialize ( $value)
	setLastError ( $err)
	Set the "last error" registry.
	unserialize ( $value)
Protected Member Functions inherited from BagOStuff
	fieldHasFlags ( $field, $flags)
	mergeFlagMaps (array $bags)
	Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map.

Private Attributes
bool	$nativeSerialize
	Whether to trust the APC implementation to serialization.
bool	$useIncrTTLArg

Static Private Attributes
static int	$CAS_MAX_ATTEMPTS = 100
	Max attempts for implicit CAS operations.

Additional Inherited Members
Public Attributes inherited from BagOStuff
const	READ_LATEST = 1
	Bitfield constants for get()/getMulti(); these are only advisory.
const	READ_VERIFIED = 2
const	WRITE_ALLOW_SEGMENTS = 16
const	WRITE_BACKGROUND = 64
const	WRITE_CACHE_ONLY = 8
const	WRITE_PRUNE_SEGMENTS = 32
const	WRITE_SYNC = 4
	Bitfield constants for set()/merge(); these are only advisory.
Protected Attributes inherited from MediumSpecificBagOStuff
callable[]	$busyCallbacks = []
string	$keyspace = 'local'
int	$lastError = self::ERR_NONE
	ERR_* class constant.
array[]	$locks = []
	Lock tracking.
array[]	$preparedValues = []
	Map of (key => (PHP variable value, serialized value))
int	$segmentationSize
	Bytes; chunk size of segmented cache values.
int	$segmentedValueMaxSize
	Bytes; maximum total size of a segmented cache value.
int	$syncTimeout
	Seconds.
Protected Attributes inherited from BagOStuff
callable null	$asyncHandler
int[]	$attrMap = []
	Map of (ATTR_* class constant => QOS_* class constant)
bool	$debugMode = false
LoggerInterface	$logger

Detailed Description

This is a wrapper for APCU's shared memory functions.

Use PHP serialization to avoid bugs and easily create CAS tokens. APCu has a memory corruption bug when the serializer is set to 'default'. See T120267, and upstream bug reports:

• https://github.com/krakjoe/apcu/issues/38
• https://github.com/krakjoe/apcu/issues/35
• https://github.com/krakjoe/apcu/issues/111

Definition at line 36 of file APCUBagOStuff.php.

Constructor & Destructor Documentation

__construct()

APCUBagOStuff::__construct

(

array

$params = []

)

See also

BagOStuff::__construct() Additional $params options include:

• logger: Psr\Log\LoggerInterface instance
• keyspace: Default keyspace for $this->makeKey()
• reportDupes: Whether to emit warning log messages for all keys that were requested more than once (requires an asyncHandler).
• syncTimeout: How long to wait with WRITE_SYNC in seconds.
• segmentationSize: The chunk size, in bytes, of segmented values. The value should not exceed the maximum size of values in the storage backend, as configured by the site administrator.
• segmentedValueMaxSize: The maximum total size, in bytes, of segmented values. This should be configured to a reasonable size give the site traffic and the amount of I/O between application and cache servers that the network can handle.

Parameters

array

$params

-param array{logger?:Psr\Log\LoggerInterface,asyncHandler?:callable,keyspace?:string,reportDupes?:bool,syncTimeout?:int,segmentationSize?:int,segmentedValueMaxSize?:int} $params

Reimplemented from MediumSpecificBagOStuff.

Definition at line 52 of file APCUBagOStuff.php.

Member Function Documentation

decr()

APCUBagOStuff::decr	(		$key,
			$value = 1,
			$flags = 0
	)

Decrease stored value of $key by $value while preserving its TTL.

Parameters

string	$key
int	$value	Value to subtract from $key (default: 1) [optional]
int	$flags	Bit field of class WRITE_* constants [optional]

Returns

int|bool New value or false on failure

Reimplemented from BagOStuff.

Definition at line 115 of file APCUBagOStuff.php.

References $CAS_MAX_ATTEMPTS.

doAdd()

APCUBagOStuff::doAdd (   $key,   $value,   $exptime = 0,   $flags = 0  )

protected

Insert an item if it does not already exist.

Parameters

string	$key
mixed	$value
int	$exptime
int	$flags	Bitfield of BagOStuff::WRITE_* constants (since 1.33)

Returns

bool Success

Reimplemented from MediumSpecificBagOStuff.

Definition at line 83 of file APCUBagOStuff.php.

References $blob, $success, MediumSpecificBagOStuff\getExpirationAsTTL(), and MediumSpecificBagOStuff\getSerialized().

doDelete()

APCUBagOStuff::doDelete (   $key,   $flags = 0  )

protected

Delete an item.

Parameters

string	$key
int	$flags	Bitfield of BagOStuff::WRITE_* constants

Returns

bool True if the item was deleted or not found, false on failure

Reimplemented from MediumSpecificBagOStuff.

Definition at line 90 of file APCUBagOStuff.php.

doGet()

APCUBagOStuff::doGet (   $key,   $flags = 0, &  $casToken = null  )

protected

Parameters

string	$key
int	$flags	Bitfield of BagOStuff::READ_* constants [optional]
mixed | null	&$casToken	Token to use for check-and-set comparisons

Returns

mixed Returns false on failure or if the item does not exist

Reimplemented from MediumSpecificBagOStuff.

Definition at line 64 of file APCUBagOStuff.php.

References $blob, and MediumSpecificBagOStuff\unserialize().

doSet()

APCUBagOStuff::doSet (   $key,   $value,   $exptime = 0,   $flags = 0  )

protected

Set an item.

Parameters

string	$key
mixed	$value
int	$exptime	Either an interval in seconds or a unix timestamp for expiry
int	$flags	Bitfield of BagOStuff::WRITE_* constants

Returns

bool Success

Reimplemented from MediumSpecificBagOStuff.

Definition at line 76 of file APCUBagOStuff.php.

References $blob, $success, MediumSpecificBagOStuff\getExpirationAsTTL(), and MediumSpecificBagOStuff\getSerialized().

incr()

APCUBagOStuff::incr	(		$key,
			$value = 1,
			$flags = 0
	)

Increase stored value of $key by $value while preserving its TTL.

Parameters

string	$key	Key to increase
int	$value	Value to add to $key (default: 1) [optional]
int	$flags	Bit field of class WRITE_* constants [optional]

Returns

int|bool New value or false on failure

Reimplemented from BagOStuff.

Definition at line 96 of file APCUBagOStuff.php.

References $CAS_MAX_ATTEMPTS.

incrWithInit()

APCUBagOStuff::incrWithInit	(		$key,
			$exptime,
			$value = 1,
			$init = null,
			$flags = 0
	)

Increase the value of the given key (no TTL change) if it exists or create it otherwise.

This will create the key with the value $init and TTL $exptime instead if not present. Callers should make sure that both ($init - $value) and $exptime are invariants for all operations to any given key. The value of $init should be at least that of $value.

Parameters

string	$key	Key built via makeKey() or makeGlobalKey()
int	$exptime	Time-to-live (in seconds) or a UNIX timestamp expiration
int	$value	Amount to increase the key value by [default: 1]
int | null	$init	Value to initialize the key to if it does not exist [default: $value]
int	$flags	Bit field of class WRITE_* constants [optional]

Returns

int|bool New value or false on failure

Since

1.24

Reimplemented from MediumSpecificBagOStuff.

Definition at line 134 of file APCUBagOStuff.php.

References $CAS_MAX_ATTEMPTS, $success, and MediumSpecificBagOStuff\getExpirationAsTTL().

Member Data Documentation

$CAS_MAX_ATTEMPTS

int APCUBagOStuff::$CAS_MAX_ATTEMPTS = 100

staticprivate

Max attempts for implicit CAS operations.

Definition at line 50 of file APCUBagOStuff.php.

Referenced by decr(), incr(), and incrWithInit().

$nativeSerialize

bool APCUBagOStuff::$nativeSerialize

private

Whether to trust the APC implementation to serialization.

Definition at line 38 of file APCUBagOStuff.php.

$useIncrTTLArg

bool APCUBagOStuff::$useIncrTTLArg

private

Definition at line 40 of file APCUBagOStuff.php.

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

• includes/libs/objectcache/APCUBagOStuff.php