MediaWiki  master
EmptyBagOStuff Class Reference

A BagOStuff object with no objects in it. More...

Inheritance diagram for EmptyBagOStuff:
Collaboration diagram for EmptyBagOStuff:

Public Member Functions

 __construct (array $params=[])
 
 decr ( $key, $value=1, $flags=0)
 Decrease stored value of $key by $value while preserving its TTL. More...
 
 incr ( $key, $value=1, $flags=0)
 Increase stored value of $key by $value while preserving its TTL. More...
 
 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...
 
 makeKeyInternal ( $keyspace, $components)
 Make a cache key for the given keyspace and 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...
 
- 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...
 
 clearLastError ()
 Clear the "last error" registry. More...
 
 delete ( $key, $flags=0)
 Delete an item. More...
 
 deleteMulti (array $keys, $flags=0)
 Batch deletion. More...
 
 deleteObjectsExpiringBefore ( $timestamp, callable $progress=null, $limit=INF)
 Delete all objects expiring before a certain date. More...
 
 get ( $key, $flags=0)
 Get an item with the given key. More...
 
 getLastError ()
 Get the "last error" registered; clearLastError() should be called manually. 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 ()
 
 lock ( $key, $timeout=6, $expiry=6, $rclass='')
 Acquire an advisory lock on a key string. More...
 
 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...
 
 set ( $key, $value, $exptime=0, $flags=0)
 Set an item. More...
 
 setMulti (array $valueByKey, $exptime=0, $flags=0)
 Batch insertion/replace. More...
 
 setNewPreparedValues (array $valueByKey)
 Make a "generic" reversible cache key from the given components. More...
 
 unlock ( $key)
 Release an advisory lock on a key string. More...
 
- Public Member Functions inherited from BagOStuff
 getCurrentTime ()
 
 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...
 
 setDebug ( $enabled)
 
 setLogger (LoggerInterface $logger)
 
 setMockTime (&$time)
 

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...
 
- 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...
 
 doSetMulti (array $data, $exptime=0, $flags=0)
 
 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)
 
 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)
 
 setLastError ( $err)
 Set the "last error" registry. More...
 
 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 ( $method, $arg0Sig, $resSig, array $genericArgs)
 Call a method on behalf of wrapper BagOStuff instance that uses "generic" keys. More...
 

Additional Inherited Members

- 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...
 
- Protected Attributes inherited from MediumSpecificBagOStuff
callable[] $busyCallbacks = []
 
int $lastError = self::ERR_NONE
 ERR_* class constant. More...
 
array[] $locks = []
 Lock tracking. 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 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 (ATTR_* class constant => QOS_* class constant) More...
 
bool $debugMode = true
 Whether to send debug log entries to the SPI logger instance. More...
 
string $keyspace
 Default keyspace; used by makeKey() More...
 
LoggerInterface $logger
 
StatsdDataFactoryInterface $stats
 
array< string, array > $wrapperInfoByPrefix = []
 Cache key processing callbacks and info for metrics. More...
 

Detailed Description

A BagOStuff object with no objects in it.

Used to provide a no-op object to calling code.

Definition at line 29 of file EmptyBagOStuff.php.

Constructor & Destructor Documentation

◆ __construct()

EmptyBagOStuff::__construct ( array  $params = [])
See also
BagOStuff::__construct() Additional $params options include:
  • logger: Psr\Log\LoggerInterface instance
  • reportDupes: Whether to emit warning log messages for all keys that were requested more than once (requires an asyncHandler).
  • syncTimeout: How long to wait with WRITE_SYNC in seconds.
  • segmentationSize: The chunk size, in bytes, of segmented values. The value should not exceed the maximum size of values in the storage backend, as configured by the site administrator.
  • segmentedValueMaxSize: The maximum total size, in bytes, of segmented values. This should be configured to a reasonable size give the site traffic and the amount of I/O between application and cache servers that the network can handle.
Parameters
array$params@phpcs:ignore Generic.Files.LineLength

Reimplemented from MediumSpecificBagOStuff.

Definition at line 30 of file EmptyBagOStuff.php.

Member Function Documentation

◆ convertGenericKey()

EmptyBagOStuff::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 74 of file EmptyBagOStuff.php.

◆ decr()

EmptyBagOStuff::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 58 of file EmptyBagOStuff.php.

◆ doAdd()

EmptyBagOStuff::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 50 of file EmptyBagOStuff.php.

◆ doDelete()

EmptyBagOStuff::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 46 of file EmptyBagOStuff.php.

◆ doGet()

EmptyBagOStuff::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 36 of file EmptyBagOStuff.php.

◆ doSet()

EmptyBagOStuff::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 42 of file EmptyBagOStuff.php.

◆ incr()

EmptyBagOStuff::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 54 of file EmptyBagOStuff.php.

◆ incrWithInit()

EmptyBagOStuff::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$keyKey built via makeKey() or makeGlobalKey()
int$exptimeTime-to-live (in seconds) or a UNIX timestamp expiration
int$valueAmount to increase the key value by [default: 1]
int | null$initValue to initialize the key to if it does not exist [default: $value]
int$flagsBit field of class WRITE_* constants [optional]
Returns
int|bool New value or false on failure
Since
1.24

Reimplemented from MediumSpecificBagOStuff.

Definition at line 62 of file EmptyBagOStuff.php.

◆ makeKeyInternal()

EmptyBagOStuff::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 70 of file EmptyBagOStuff.php.

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

◆ merge()

EmptyBagOStuff::merge (   $key,
callable  $callback,
  $exptime = 0,
  $attempts = 10,
  $flags = 0 
)

Merge changes into the existing cache value (possibly creating a new one)

The callback function returns the new value given the current value (which will be false if not present), and takes the arguments: (this BagOStuff, cache key, current value, TTL). The TTL parameter is reference set to $exptime. It can be overriden in the callback. Nothing is stored nor deleted if the callback returns false.

Parameters
string$key
callable$callbackCallback method to be executed
int$exptimeEither an interval in seconds or a unix timestamp for expiry
int$attemptsThe amount of times to attempt a merge in case of failure
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool Success

Reimplemented from MediumSpecificBagOStuff.

Definition at line 66 of file EmptyBagOStuff.php.


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