Base class for memcached clients. More...

Inheritance diagram for MemcachedBagOStuff:

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Collaboration diagram for MemcachedBagOStuff:

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Public Member Functions
	__construct (array $params)

	makeKeyInternal ( $keyspace, $components)
	Construct a cache key. More...

	validateKeyEncoding ( $key)
	Ensure that a key is safe to use (contains no control characters and no characters above the ASCII range.) More...

Public Member Functions inherited from MediumSpecificBagOStuff
	add ( $key, $value, $exptime=0, $flags=0)
	Insert an item if it does not already exist. More...

	addBusyCallback (callable $workCallback)
	Let a callback be run to avoid wasting time on special blocking calls. More...

	changeTTL ( $key, $exptime=0, $flags=0)
	Change the expiration on a key if it exists. More...

	changeTTLMulti (array $keys, $exptime, $flags=0)
	Change the expiration of multiple keys that exist. More...

	delete ( $key, $flags=0)
	Delete an item. More...

	deleteMulti (array $keys, $flags=0)
	Batch deletion. More...

	deleteObjectsExpiringBefore ( $timestamp, callable $progress=null, $limit=INF, string $tag=null)
	Delete all objects expiring before a certain date. More...

	get ( $key, $flags=0)
	Get an item with the given key. More...

	getMulti (array $keys, $flags=0)
	Get an associative array containing the item for each of the keys that have items. More...

	getQoS ( $flag)

	getSegmentationSize ()

	getSegmentedValueMaxSize ()

	incrWithInit ( $key, $exptime, $step=1, $init=null, $flags=0)
	Increase the value of the given key (no TTL change) if it exists or create it otherwise. More...

	lock ( $key, $timeout=6, $exptime=6, $rclass='')

	makeGlobalKey ( $collection,... $components)
	Make a cache key for the default keyspace and given components. More...

	makeKey ( $collection,... $components)
	Make a cache key for the global keyspace and given components. More...

	merge ( $key, callable $callback, $exptime=0, $attempts=10, $flags=0)
	Merge changes into the existing cache value (possibly creating a new one) More...

	set ( $key, $value, $exptime=0, $flags=0)
	Set an item. More...

	setMulti (array $valueByKey, $exptime=0, $flags=0)
	Batch insertion/replace. More...

	unlock ( $key)
	Release an advisory lock on a key string. More...

Public Member Functions inherited from BagOStuff
	clearLastError ()
	Clear the "last error" registry. More...

	decr ( $key, $value=1, $flags=0)
	Decrease stored value of $key by $value while preserving its TTL. More...

	getCurrentTime ()

	getLastError ( $watchPoint=0)
	Get the "last error" registry. More...

	getLogger ()

	getScopedLock ( $key, $timeout=6, $exptime=30, $rclass='')
	Get a lightweight exclusive self-unlocking lock. More...

	getWithSetCallback ( $key, $exptime, $callback, $flags=0)
	Get an item, regenerating and setting it if not found. More...

	incr ( $key, $value=1, $flags=0)
	Increase stored value of $key by $value while preserving its TTL. More...

	isKeyGlobal ( $key)
	Check whether a cache key is in the global keyspace. More...

	registerWrapperInfoForStats (string $prefixComponent, string $statsGroup, callable $collectionCallback)
	Register info about a caching layer class that uses BagOStuff as a backing store. More...

	setLogger (LoggerInterface $logger)

	setMockTime (&$time)

	setNewPreparedValues (array $valueByKey)
	Stage a set of new key values for storage and estimate the amount of bytes needed. More...

	watchErrors ()
	Get a "watch point" token that can be used to get the "last error" to occur after now. More...

Protected Member Functions
	doIncrWithInit ( $key, $exptime, $step, $init, $flags)

	doIncrWithInitAsync ( $key, $exptime, $step, $init)

	doIncrWithInitSync ( $key, $exptime, $step, $init)

	fixExpiry ( $exptime)

	stripRouteFromKey ( $key)

	validateKeyAndPrependRoute ( $key)

Protected Member Functions inherited from MediumSpecificBagOStuff
	cas ( $casToken, $key, $value, $exptime=0, $flags=0)
	Set an item if the current CAS token matches the provided CAS token. More...

	convertGenericKey ( $key)
	Convert a "generic" reversible cache key into one for this cache. More...

	debug ( $text)

	doAdd ( $key, $value, $exptime=0, $flags=0)
	Insert an item if it does not already exist. More...

	doCas ( $casToken, $key, $value, $exptime=0, $flags=0)
	Set an item if the current CAS token matches the provided CAS token. More...

	doChangeTTL ( $key, $exptime, $flags)

	doChangeTTLMulti (array $keys, $exptime, $flags=0)

	doDelete ( $key, $flags=0)
	Delete an item. More...

	doDeleteMulti (array $keys, $flags=0)

	doGet ( $key, $flags=0, &$casToken=null)
	Get an item. More...

	doGetMulti (array $keys, $flags=0)
	Get an associative array containing the item for each of the keys that have items. More...

	doLock ( $key, $timeout, $exptime)

	doSet ( $key, $value, $exptime=0, $flags=0)
	Set an item. More...

	doSetMulti (array $data, $exptime=0, $flags=0)

	doUnlock ( $key)

	getExpirationAsTimestamp ( $exptime)
	Convert an optionally relative timestamp to an absolute time. More...

	getExpirationAsTTL ( $exptime)
	Convert an optionally absolute expiry time to a relative time. More...

	getSerialized ( $value, $key)
	Get the serialized form a value, logging a warning if it involves custom classes. More...

	isInteger ( $value)
	Check if a value is an integer. More...

	isRelativeExpiration ( $exptime)

	makeLockKey ( $key)

	makeValueOrSegmentList ( $key, $value, $exptime, $flags, &$ok)
	Make the entry to store at a key (inline or segment list), storing any segments. More...

	mergeViaCas ( $key, callable $callback, $exptime, $attempts, $flags)

	resolveSegments ( $key, $mainValue)
	Get and reassemble the chunks of blob at the given key. More...

	serialize ( $value)

	tokensMatch ( $value, $otherValue)

	unserialize ( $value)

	updateOpStats (string $op, array $keyInfo)

Protected Member Functions inherited from BagOStuff
	componentsFromGenericKey ( $key)
	Extract the components from a "generic" reversible cache key. More...

	determineKeyPrefixForStats ( $key)

	fieldHasFlags ( $field, $flags)

	genericKeyFromComponents (... $components)
	At a minimum, there must be a keyspace and collection name component. More...

	mergeFlagMaps (array $bags)
	Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map. More...

	proxyCall (string $method, int $arg0Sig, int $resSig, array $genericArgs, BagOStuff $wrapper)
	Call a method on behalf of wrapper BagOStuff instance that uses "generic" keys. More...

	setLastError ( $error)
	Set the "last error" registry due to a problem encountered during an attempted operation. More...

Protected Attributes
string	$routingPrefix
	Routing prefix appended to keys during operations. More...

Protected Attributes inherited from MediumSpecificBagOStuff
array< string, array >	$locks = []
	Map of (key => (class LOCK_* constant => value) More...

float	$maxLockSendDelay = 0.05
	Seconds; maximum expected seconds for a lock ping to reach the backend. More...

int	$segmentationSize
	Bytes; chunk size of segmented cache values. More...

int	$segmentedValueMaxSize
	Bytes; maximum total size of a segmented cache value. More...

const	LOCK_DEPTH = 1

const	LOCK_EXPIRY = 3

const	LOCK_RCLASS = 0

const	LOCK_TIME = 2

const	METRIC_OP_ADD = 'add'

const	METRIC_OP_CAS = 'cas'

const	METRIC_OP_CHANGE_TTL = 'change_ttl'

const	METRIC_OP_DECR = 'decr'

const	METRIC_OP_DELETE = 'delete'

const	METRIC_OP_GET = 'get'

const	METRIC_OP_INCR = 'incr'

const	METRIC_OP_SET = 'set'

const	PASS_BY_REF = -1
	Idiom for doGet() to return extra information by reference. More...

Protected Attributes inherited from BagOStuff
callable null	$asyncHandler

int[]	$attrMap = []
	Map of (BagOStuff:ATTR_* constant => BagOStuff:QOS_* constant) More...

string	$keyspace
	Default keyspace; used by makeKey() More...

int	$lastError = self::ERR_NONE
	BagOStuff:ERR_* constant of the last error that occurred. More...

int	$lastErrorId = 0
	Error event sequence number of the last error that occurred. More...

LoggerInterface	$logger

StatsdDataFactoryInterface	$stats

array< string, array >	$wrapperInfoByPrefix = []
	Cache key processing callbacks and info for metrics. More...

Additional Inherited Members
Public Attributes inherited from BagOStuff
const	MAX_CONFLICTS_ONE = 1
	Abort after the first merge conflict. More...

const	READ_LATEST = 1
	Bitfield constants for get()/getMulti(); these are only advisory. More...

const	READ_VERIFIED = 2
	Promise that the caller handles detection of staleness. More...

const	WRITE_ALLOW_SEGMENTS = 16
	Allow partitioning of the value if it is a large string. More...

const	WRITE_BACKGROUND = 64
	If supported, do not block on write operation completion; instead, treat writes as succesful based on whether they could be buffered. More...

const	WRITE_CACHE_ONLY = 8
	Bitfield constants for set()/merge(); these are only advisory. More...

const	WRITE_PRUNE_SEGMENTS = 32
	Delete all the segments if the value is partitioned. More...

Public Attributes inherited from Wikimedia\LightweightObjectStore\StorageAwareness
const	ATTR_DURABILITY = 2
	Durability of writes; see QOS_DURABILITY_* (higher means stronger) More...

const	ATTR_EMULATION = 1
	Emulation/fallback mode; see QOS_EMULATION_*; higher is better. More...

const	ERR_NO_RESPONSE = 1
	Storage medium failed to yield a complete response to an operation. More...

const	ERR_NONE = 0
	No storage medium error. More...

const	ERR_UNEXPECTED = 3
	Storage medium operation failed due to usage limitations or an I/O error. More...

const	ERR_UNREACHABLE = 2
	Storage medium could not be reached to establish a connection. More...

const	QOS_DURABILITY_DISK = 4
	Data is saved to disk and writes do not usually block on fsync() More...

const	QOS_DURABILITY_NONE = 1
	Data is never saved to begin with (blackhole store) More...

const	QOS_DURABILITY_RDBMS = 5
	Data is saved to disk and writes usually block on fsync(), like a standard RDBMS. More...

const	QOS_DURABILITY_SCRIPT = 2
	Data is lost at the end of the current web request or CLI script. More...

const	QOS_DURABILITY_SERVICE = 3
	Data is lost once the service storing the data restarts. More...

const	QOS_EMULATION_SQL = 1
	Fallback disk-based SQL store. More...

const	QOS_UNKNOWN = INF
	Generic "unknown" value; useful for comparisons (always "good enough") More...

Static Protected Attributes inherited from BagOStuff
static int	$nextErrorMonitorId = 1
	Next sequence number to use for watch/error events. More...

Detailed Description

Base class for memcached clients.

Definition at line 29 of file MemcachedBagOStuff.php.

Constructor & Destructor Documentation

◆ __construct()

MemcachedBagOStuff::__construct ( array $params )

Parameters

array

$params

Additional parameters include:

routingPrefix: a routing prefix of the form "<datacenter>/<cluster>/" used to convey the location/strategy to use for handling keys accessed from this instance. The prefix is prepended to keys during cache operations. The memcached proxy must preserve these prefixes in any responses that include requested keys (e.g. get/gets). The proxy is also assumed to strip the routing prefix from the stored key name, which allows for unprefixed access. This can be used with mcrouter. [optional]

Reimplemented from MediumSpecificBagOStuff.

Definition at line 42 of file MemcachedBagOStuff.php.

References Wikimedia\LightweightObjectStore\StorageAwareness\ATTR_DURABILITY, and Wikimedia\LightweightObjectStore\StorageAwareness\QOS_DURABILITY_SERVICE.