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HashBagOStuff Class Reference

Simple store for keeping values in an associative array for the current process. More...

Inheritance diagram for HashBagOStuff:
Collaboration diagram for HashBagOStuff:

Public Member Functions

 __construct ( $params=[])
 
 clear ()
 Clear all values in cache. More...
 
 decr ( $key, $value=1, $flags=0)
 Decrease stored value of $key by $value while preserving its TTL. More...
 
 hasKey ( $key)
 Does this bag have a non-null value for the given key? More...
 
 incr ( $key, $value=1, $flags=0)
 Increase stored value of $key by $value while preserving its TTL. More...
 
 makeKeyInternal ( $keyspace, $components)
 Make a cache key for the given keyspace and components. More...
 
 setNewPreparedValues (array $valueByKey)
 Make a "generic" reversible cache key from the given components. More...
 
- Public Member Functions inherited from MediumSpecificBagOStuff
 __construct (array $params=[])
 
 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, $value=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...
 
 getCurrentTime ()
 
 getLastError ( $watchPoint=0)
 Get the "last error" registry. More...
 
 getLogger ()
 
 getScopedLock ( $key, $timeout=6, $expiry=30, $rclass='')
 Get a lightweight exclusive self-unlocking lock. More...
 
 getWithSetCallback ( $key, $exptime, $callback, $flags=0)
 Get an item with the given key, regenerating and setting it if not found. 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)
 
 watchErrors ()
 Get a "watch point" token that can be used to get the "last error" to occur after now. More...
 

Public Attributes

const KEY_CAS = 2
 
const KEY_EXP = 1
 
const KEY_VAL = 0
 
- Public Attributes inherited from BagOStuff
const READ_LATEST = 1
 Bitfield constants for get()/getMulti(); these are only advisory. More...
 
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. 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 response. 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. 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...
 

Protected Member Functions

 convertGenericKey ( $key)
 Convert a "generic" reversible cache key into one for this cache. More...
 
 doAdd ( $key, $value, $exptime=0, $flags=0)
 Insert an item if it does not already exist. More...
 
 doDelete ( $key, $flags=0)
 Delete an item. More...
 
 doGet ( $key, $flags=0, &$casToken=null)
 
 doSet ( $key, $value, $exptime=0, $flags=0)
 Set an item. More...
 
 expire ( $key)
 
- Protected Member Functions inherited from MediumSpecificBagOStuff
 cas ( $casToken, $key, $value, $exptime=0, $flags=0)
 Check and set an item. More...
 
 debug ( $text)
 
 doCas ( $casToken, $key, $value, $exptime=0, $flags=0)
 Check and set an item. More...
 
 doChangeTTL ( $key, $exptime, $flags)
 
 doChangeTTLMulti (array $keys, $exptime, $flags=0)
 
 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. More...
 
 doLock ( $key, $timeout, $exptime)
 
 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, using any applicable prepared value. More...
 
 guessSerialValueSize ( $value, $depth=0, &$loops=0)
 Estimate the size of a variable once serialized. More...
 
 isInteger ( $value)
 Check if a value is an integer. More...
 
 isRelativeExpiration ( $exptime)
 
 makeLockKey ( $key)
 
 makeValueOrSegmentList ( $key, $value, $exptime, $flags)
 Determine the entry (inline or segment list) to store under a key to save the value. 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)
 
 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

mixed[] $bag = []
 
int double $maxCacheKeys
 Max entries allowed, INF for unlimited. More...
 
- Protected Attributes inherited from MediumSpecificBagOStuff
callable[] $busyCallbacks = []
 
array< string, array > $locks = []
 Map of (key => (class, depth, expiry) More...
 
array[] $preparedValues = []
 Map of (key => (PHP variable value, serialized value)) More...
 
int $segmentationSize
 Bytes; chunk size of segmented cache values. More...
 
int $segmentedValueMaxSize
 Bytes; maximum total size of a segmented cache value. More...
 
int $syncTimeout
 Seconds. 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'
 
- 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...
 

Private Attributes

string $token
 CAS token prefix for this instance. More...
 

Static Private Attributes

static int $casCounter = 0
 CAS token counter. More...
 

Additional Inherited Members

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

Detailed Description

Simple store for keeping values in an associative array for the current process.

Data will not persist and is not shared with other processes.

@newable

Definition at line 32 of file HashBagOStuff.php.

Constructor & Destructor Documentation

◆ __construct()

HashBagOStuff::__construct (   $params = [])
Stability: stable
to call
Parameters
array$paramsAdditional parameters include:
  • maxKeys : only allow this many keys (using oldest-first eviction) @phpcs:ignore Generic.Files.LineLength

Definition at line 55 of file HashBagOStuff.php.

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

Member Function Documentation

◆ clear()

HashBagOStuff::clear ( )

Clear all values in cache.

Definition at line 140 of file HashBagOStuff.php.

◆ convertGenericKey()

HashBagOStuff::convertGenericKey (   $key)
protected

Convert a "generic" reversible cache key into one for this cache.

See also
BagOStuff::genericKeyFromComponents()
Parameters
string$keyKeyspace-prepended list of encoded components as a colon-separated value
Returns
string Keyspace-prepended list of encoded components as a colon-separated value

Reimplemented from MediumSpecificBagOStuff.

Definition at line 184 of file HashBagOStuff.php.

◆ decr()

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

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

Parameters
string$key
int$valueValue to subtract from $key (default: 1) [optional]
int$flagsBit field of class WRITE_* constants [optional]
Returns
int|bool New value or false on failure

Reimplemented from BagOStuff.

Definition at line 133 of file HashBagOStuff.php.

References incr().

◆ doAdd()

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

Insert an item if it does not already exist.

Parameters
string$key
mixed$value
int$exptime
int$flagsBitfield of BagOStuff::WRITE_* constants (since 1.33)
Returns
bool Success

Reimplemented from MediumSpecificBagOStuff.

Definition at line 107 of file HashBagOStuff.php.

References doSet(), expire(), and hasKey().

◆ doDelete()

HashBagOStuff::doDelete (   $key,
  $flags = 0 
)
protected

Delete an item.

Parameters
string$key
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool True if the item was deleted or not found, false on failure

Reimplemented from MediumSpecificBagOStuff.

Definition at line 115 of file HashBagOStuff.php.

Referenced by expire().

◆ doGet()

HashBagOStuff::doGet (   $key,
  $flags = 0,
$casToken = null 
)
protected
Parameters
string$key
int$flagsBitfield of BagOStuff::READ_* constants [optional]
mixed | null&$casTokencas() token if MediumSpecificBagOStuff::PASS_BY_REF [returned]
Returns
mixed Returns false on failure or if the item does not exist

Reimplemented from MediumSpecificBagOStuff.

Definition at line 69 of file HashBagOStuff.php.

References expire(), hasKey(), KEY_CAS, and KEY_VAL.

◆ doSet()

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

Set an item.

Parameters
string$key
mixed$value
int$exptimeEither an interval in seconds or a unix timestamp for expiry
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool Success

Reimplemented from MediumSpecificBagOStuff.

Definition at line 89 of file HashBagOStuff.php.

References $casCounter, and MediumSpecificBagOStuff\getExpirationAsTimestamp().

Referenced by doAdd().

◆ expire()

HashBagOStuff::expire (   $key)
protected
Parameters
string$key
Returns
bool

Definition at line 148 of file HashBagOStuff.php.

References doDelete(), BagOStuff\getCurrentTime(), and KEY_EXP.

Referenced by doAdd(), and doGet().

◆ hasKey()

HashBagOStuff::hasKey (   $key)

Does this bag have a non-null value for the given key?

Parameters
string$key
Returns
bool
Since
1.27

Definition at line 176 of file HashBagOStuff.php.

Referenced by doAdd(), and doGet().

◆ incr()

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

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

Parameters
string$keyKey to increase
int$valueValue to add to $key (default: 1) [optional]
int$flagsBit field of class WRITE_* constants [optional]
Returns
int|bool New value or false on failure

Reimplemented from BagOStuff.

Definition at line 121 of file HashBagOStuff.php.

References MediumSpecificBagOStuff\isInteger(), and KEY_VAL.

Referenced by decr().

◆ makeKeyInternal()

HashBagOStuff::makeKeyInternal (   $keyspace,
  $components 
)

Make a cache key for the given keyspace and components.

Long components might be converted to respective hashes due to size constraints. In extreme cases, all of them might be combined into a single hash component.

Access: internal
This method should not be used outside of BagOStuff (since 1.36)
Parameters
string$keyspaceKeyspace component
string[] | int[]$componentsKey components (key collection name first)
Returns
string Keyspace-prepended list of encoded components as a colon-separated value
Since
1.27

Reimplemented from BagOStuff.

Definition at line 180 of file HashBagOStuff.php.

References BagOStuff\$keyspace, and BagOStuff\genericKeyFromComponents().

◆ setNewPreparedValues()

HashBagOStuff::setNewPreparedValues ( array  $valueByKey)

Make a "generic" reversible cache key from the given components.

All previously prepared values will be cleared. Each of the new prepared values will be individually cleared as they get used by write operations for that key. This is done to avoid unchecked growth in PHP memory usage.

Example usage:

$valueByKey = [ $key1 => $value1, $key2 => $value2, $key3 => $value3 ];
$cache->setNewPreparedValues( $valueByKey );
$cache->set( $key1, $value1, $cache::TTL_HOUR );
$cache->setMulti( [ $key2 => $value2, $key3 => $value3 ], $cache::TTL_HOUR );

This is only useful if the caller needs an estimate of the serialized object sizes. The caller cannot know the serialization format and even if it did, it could be expensive to serialize complex values twice just to get the size information before writing them to cache. This method solves both problems by making the cache instance do the serialization and having it reuse the result when the cache write happens.

Parameters
array$valueByKeyMap of (cache key => PHP variable value to serialize)
Returns
int[]|null[] Corresponding list of size estimates (null for invalid values)
Since
1.35

Reimplemented from MediumSpecificBagOStuff.

Definition at line 159 of file HashBagOStuff.php.

References MediumSpecificBagOStuff\guessSerialValueSize().

Member Data Documentation

◆ $bag

mixed [] HashBagOStuff::$bag = []
protected

Definition at line 34 of file HashBagOStuff.php.

◆ $casCounter

int HashBagOStuff::$casCounter = 0
staticprivate

CAS token counter.

Definition at line 42 of file HashBagOStuff.php.

Referenced by doSet().

◆ $maxCacheKeys

int double HashBagOStuff::$maxCacheKeys
protected

Max entries allowed, INF for unlimited.

Definition at line 36 of file HashBagOStuff.php.

◆ $token

string HashBagOStuff::$token
private

CAS token prefix for this instance.

Definition at line 39 of file HashBagOStuff.php.

◆ KEY_CAS

const HashBagOStuff::KEY_CAS = 2

Definition at line 46 of file HashBagOStuff.php.

Referenced by doGet().

◆ KEY_EXP

const HashBagOStuff::KEY_EXP = 1

Definition at line 45 of file HashBagOStuff.php.

Referenced by expire().

◆ KEY_VAL

const HashBagOStuff::KEY_VAL = 0

Definition at line 44 of file HashBagOStuff.php.

Referenced by doGet(), and incr().


The documentation for this class was generated from the following file:
$cache
$cache
Definition: mcc.php:33