Handles a simple LRU key/value map with a maximum number of entries. More...

Inheritance diagram for MapCacheLRU:

[legend]

Collaboration diagram for MapCacheLRU:

[legend]

Public Member Functions
	__construct (int $maxKeys)

	__serialize ()

	__unserialize ( $data)

	clear ( $keys=null)
	Clear one or several cache entries, or all cache entries.

	get ( $key, $maxAge=INF, $default=null)
	Get the value for a key.

	getAllKeys ()

	getField ( $key, $field, $maxAge=INF)

	getMaxSize ()
	Get the maximum number of keys allowed.

	getWithSetCallback ( $key, callable $callback, $rank=self::RANK_TOP, $maxAge=INF)
	Get an item with the given key, producing and setting it if not found.

	has ( $key, $maxAge=INF)
	Check if a key exists.

	hasField ( $key, $field, $maxAge=INF)

	serialize ()

	set ( $key, $value, $rank=self::RANK_TOP)
	Set a key/value pair.

	setField ( $key, $field, $value, $initRank=self::RANK_TOP)

	setMaxSize (int $maxKeys)
	Resize the maximum number of cache entries, removing older entries as needed.

	setMockTime (&$time)

	toArray ()

	unserialize ( $serialized)

Static Public Member Functions
static	newFromArray (array $values, $maxKeys)

Protected Member Functions
	getCurrentTime ()

Private Member Functions
	getKeyAge ( $key)

	getKeyFieldAge ( $key, $field)

	ping ( $key)
	Push an entry to the top of the cache.

Private Attributes
array	$cache = []
	Map of (key => value)

float	$epoch
	Default entry timestamp if not specified.

int	$maxCacheKeys
	Max number of entries.

array	$timestamps = []
	Map of (key => (UNIX timestamp, (field => UNIX timestamp)))

float null	$wallClockOverride

Detailed Description

Handles a simple LRU key/value map with a maximum number of entries.

The last-modification timestamp of entries is internally tracked so that callers can specify the maximum acceptable age of entries in calls to the has() method. As a convenience, the hasField(), getField(), and setField() methods can be used for entries that are field/value maps themselves; such fields will have their own internally tracked last-modification timestamp.

Since: 1.23

Definition at line 36 of file MapCacheLRU.php.

Constructor & Destructor Documentation

◆ __construct()

MapCacheLRU::__construct ( int $maxKeys )

Parameters

int $maxKeys Maximum number of entries allowed (min 1)

Definition at line 61 of file MapCacheLRU.php.

References getCurrentTime().

Member Function Documentation

◆ __serialize()

MapCacheLRU::__serialize ( )

Definition at line 364 of file MapCacheLRU.php.

References $cache.

◆ __unserialize()

MapCacheLRU::__unserialize ( $data )

Definition at line 376 of file MapCacheLRU.php.

◆ clear()

MapCacheLRU::clear ( $keys = null )

Clear one or several cache entries, or all cache entries.

Parameters

string | array | null $keys

Returns: void

Definition at line 289 of file MapCacheLRU.php.

References $keys.

◆ get()

MapCacheLRU::get	(	$key,
		$maxAge = `INF`,
		$default = `null`
	)

Get the value for a key.

This returns null if the key is not set. If the item is already set, it will be pushed to the top of the cache.

Parameters

string	$key
float	$maxAge	Ignore items older than this many seconds [default: INF]
mixed \| null	$default	Value to return if no key is found [default: null]

Returns: mixed Returns $default if the key was not found or is older than $maxAge

Since: 1.32 Added $maxAge; 1.34 Added $default

Although sometimes this can be tainted, taint-check doesn't distinguish separate instances of MapCacheLRU, so assume untainted to cut down on false positives. See T272134.

Returns: -taint none

Definition at line 172 of file MapCacheLRU.php.

References has(), and ping().

◆ getAllKeys()

MapCacheLRU::getAllKeys ( )

Returns: array

Since: 1.25

Definition at line 251 of file MapCacheLRU.php.

◆ getCurrentTime()

MapCacheLRU::getCurrentTime ( )

protected

Returns: float UNIX timestamp

Definition at line 392 of file MapCacheLRU.php.

Referenced by __construct(), getKeyAge(), getKeyFieldAge(), set(), and setField().

◆ getField()

MapCacheLRU::getField	(	$key,
		$field,
		$maxAge = `INF`
	)

Parameters

string \| int	$key
string \| int	$field
float	$maxAge	Ignore items older than this many seconds [default: INF]

Returns: mixed Returns null if the key was not found or is older than $maxAge

Since: 1.32 Added $maxAge

Definition at line 239 of file MapCacheLRU.php.

References hasField().

◆ getKeyAge()

MapCacheLRU::getKeyAge ( $key )

private

Parameters

string | int $key

Returns: float UNIX timestamp; the age of the given entry

Definition at line 347 of file MapCacheLRU.php.

References getCurrentTime().

Referenced by has().

◆ getKeyFieldAge()

MapCacheLRU::getKeyFieldAge	(	$key,
		$field
	)

private

Parameters

string \| int	$key
string \| int \| null	$field

Returns: float UNIX timestamp; the age of the given entry field

Definition at line 358 of file MapCacheLRU.php.

References getCurrentTime().

Referenced by hasField().

◆ getMaxSize()

MapCacheLRU::getMaxSize ( )

Get the maximum number of keys allowed.

Returns: int

Since: 1.32

Definition at line 307 of file MapCacheLRU.php.

◆ getWithSetCallback()

MapCacheLRU::getWithSetCallback	(		$key,
		callable	$callback,
			$rank = `self::RANK_TOP`,
			$maxAge = `INF`
	)

Get an item with the given key, producing and setting it if not found.

If the callback returns false, then nothing is stored.

Since: 1.28

Parameters

string	$key
callable	$callback	Callback that will produce the value
float	$rank	Bottom fraction of the list where keys start off [default: 1.0]
float	$maxAge	Ignore items older than this many seconds [default: INF]

Returns: mixed The cached value if found or the result of $callback otherwise

Since: 1.32 Added $maxAge

Definition at line 268 of file MapCacheLRU.php.

References has().

◆ has()

MapCacheLRU::has	(	$key,
		$maxAge = `INF`
	)

Check if a key exists.

Parameters

string \| int	$key
float	$maxAge	Ignore items older than this many seconds [default: INF]

Returns: bool

Since: 1.32 Added $maxAge

Definition at line 142 of file MapCacheLRU.php.

References getKeyAge().

Referenced by get(), getWithSetCallback(), set(), and setField().

◆ hasField()

MapCacheLRU::hasField	(	$key,
		$field,
		$maxAge = `INF`
	)

Parameters

string \| int	$key
string \| int	$field
float	$maxAge	Ignore items older than this many seconds [default: INF]

Returns: bool

Since: 1.32 Added $maxAge

Definition at line 216 of file MapCacheLRU.php.

References getKeyFieldAge().

Referenced by getField().

◆ newFromArray()

static MapCacheLRU::newFromArray	(	array	$values,
			$maxKeys
	)

static

Parameters

array	$values	Key/value map in order of increasingly recent access
int	$maxKeys

Returns: MapCacheLRU

Since: 1.30

Definition at line 77 of file MapCacheLRU.php.

◆ ping()

MapCacheLRU::ping ( $key )

private

Push an entry to the top of the cache.

Parameters

string $key

Definition at line 337 of file MapCacheLRU.php.

Referenced by get(), set(), and setField().

◆ serialize()

MapCacheLRU::serialize ( )

Definition at line 372 of file MapCacheLRU.php.

◆ set()

MapCacheLRU::set	(	$key,
		$value,
		$rank = `self::RANK_TOP`
	)

Set a key/value pair.

This will prune the cache if it gets too large based on LRU. If the item is already set, it will be pushed to the top of the cache.

To reduce evictions due to one-off use of many new keys, $rank can be set to have keys start at the top of a bottom fraction of the list. A value of 3/8 means values start at the top of the bottom 3/8s of the list and are moved to the top of the list when accessed a second time.

Parameters

string	$key
mixed	$value
float	$rank	Bottom fraction of the list where keys start off [default: 1.0]

Returns: void

Definition at line 109 of file MapCacheLRU.php.

References getCurrentTime(), has(), and ping().

◆ setField()

MapCacheLRU::setField	(	$key,
		$field,
		$value,
		$initRank = `self::RANK_TOP`
	)

Parameters

string \| int	$key
string \| int	$field
mixed	$value
float	$initRank

Definition at line 188 of file MapCacheLRU.php.

References $type, getCurrentTime(), has(), and ping().

◆ setMaxSize()

MapCacheLRU::setMaxSize ( int $maxKeys )

Resize the maximum number of cache entries, removing older entries as needed.

Parameters

int $maxKeys Maximum number of entries allowed (min 1)

Returns: void

Since: 1.32

Definition at line 318 of file MapCacheLRU.php.

◆ setMockTime()

MapCacheLRU::setMockTime ( & $time )

Parameters

float | null &$time Mock UNIX timestamp for testing

Definition at line 400 of file MapCacheLRU.php.

◆ toArray()

MapCacheLRU::toArray ( )

Returns: array Key/value map in order of increasingly recent access

Since: 1.30

Definition at line 90 of file MapCacheLRU.php.

References $cache.

◆ unserialize()

MapCacheLRU::unserialize ( $serialized )

Definition at line 384 of file MapCacheLRU.php.

Member Data Documentation

◆ $cache

array MapCacheLRU::$cache = []

private

Map of (key => value)

Definition at line 38 of file MapCacheLRU.php.

◆ $epoch

float MapCacheLRU::$epoch

private

Default entry timestamp if not specified.

Definition at line 42 of file MapCacheLRU.php.

◆ $maxCacheKeys

int MapCacheLRU::$maxCacheKeys

private

Max number of entries.

Definition at line 45 of file MapCacheLRU.php.

◆ $timestamps

array MapCacheLRU::$timestamps = []

private

Map of (key => (UNIX timestamp, (field => UNIX timestamp)))

Definition at line 40 of file MapCacheLRU.php.

◆ $wallClockOverride

float null MapCacheLRU::$wallClockOverride

private

Definition at line 48 of file MapCacheLRU.php.

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

includes/libs/MapCacheLRU.php

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ __serialize()

◆ __unserialize()

◆ clear()

◆ get()

◆ getAllKeys()

◆ getCurrentTime()

◆ getField()

◆ getKeyAge()

◆ getKeyFieldAge()

◆ getMaxSize()

◆ getWithSetCallback()

◆ has()

◆ hasField()

◆ newFromArray()

◆ ping()

◆ serialize()

◆ set()

◆ setField()

◆ setMaxSize()

◆ setMockTime()

◆ toArray()

◆ unserialize()

Member Data Documentation

◆ $cache

◆ $epoch

◆ $maxCacheKeys

◆ $timestamps

◆ $wallClockOverride