MediaWiki REL1_37
MediumSpecificBagOStuff Class Reference

Storage medium specific cache for storing items (e.g. More...

Inheritance diagram for MediumSpecificBagOStuff:
Collaboration diagram for MediumSpecificBagOStuff:

Public Member Functions

 __construct (array $params=[])
 
 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, string $tag=null)
 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 ()
 
 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.
 
 lock ( $key, $timeout=6, $exptime=6, $rclass='')
 
 makeGlobalKey ( $collection,... $components)
 Make a cache key for the default keyspace and given components.
 
 makeKey ( $collection,... $components)
 Make a cache key for the global keyspace and given components.
 
 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 $valueByKey, $exptime=0, $flags=0)
 Batch insertion/replace.
 
 setNewPreparedValues (array $valueByKey)
 Make a "generic" reversible cache key from the given components.
 
 unlock ( $key)
 Release an advisory lock on a key string.
 
- Public Member Functions inherited from BagOStuff
 decr ( $key, $value=1, $flags=0)
 Decrease stored value of $key by $value while preserving its TTL.
 
 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.
 
 incr ( $key, $value=1, $flags=0)
 Increase stored value of $key by $value while preserving its TTL.
 
 isKeyGlobal ( $key)
 Check whether a cache key is in the global keyspace.
 
 makeKeyInternal ( $keyspace, $components)
 Make a cache key for the given keyspace and components.
 
 registerWrapperInfoForStats (string $prefixComponent, string $statsGroup, callable $collectionCallback)
 Register info about a caching layer class that uses BagOStuff as a backing store.
 
 setDebug ( $enabled)
 
 setLogger (LoggerInterface $logger)
 
 setMockTime (&$time)
 

Protected Member Functions

 cas ( $casToken, $key, $value, $exptime=0, $flags=0)
 Check and set an item.
 
 convertGenericKey ( $key)
 Convert a "generic" reversible cache key into one for this cache.
 
 debug ( $text)
 
 doAdd ( $key, $value, $exptime=0, $flags=0)
 Insert an item if it does not already exist.
 
 doCas ( $casToken, $key, $value, $exptime=0, $flags=0)
 Check and set an item.
 
 doChangeTTL ( $key, $exptime, $flags)
 
 doChangeTTLMulti (array $keys, $exptime, $flags=0)
 
 doDelete ( $key, $flags=0)
 Delete an item.
 
 doDeleteMulti (array $keys, $flags=0)
 
 doGet ( $key, $flags=0, &$casToken=null)
 
 doGetMulti (array $keys, $flags=0)
 Get an associative array containing the item for each of the keys that have items.
 
 doLock ( $key, $timeout, $exptime)
 
 doSet ( $key, $value, $exptime=0, $flags=0)
 Set an item.
 
 doSetMulti (array $data, $exptime=0, $flags=0)
 
 doUnlock ( $key)
 
 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)
 
 makeLockKey ( $key)
 
 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)
 
 updateOpStats (string $op, array $keyInfo)
 
- Protected Member Functions inherited from BagOStuff
 componentsFromGenericKey ( $key)
 Extract the components from a "generic" reversible cache key.
 
 determineKeyPrefixForStats ( $key)
 
 fieldHasFlags ( $field, $flags)
 
 genericKeyFromComponents (... $components)
 At a minimum, there must be a keyspace and collection name component.
 
 mergeFlagMaps (array $bags)
 Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map.
 
 proxyCall ( $method, $arg0Sig, $resSig, array $genericArgs)
 Call a method on behalf of wrapper BagOStuff instance that uses "generic" keys.
 

Protected Attributes

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

Private Member Functions

 checkIterableMapSerializability ( $value, $key)
 
 checkValueSerializability ( $value, $key)
 Log if a new cache value does not appear suitable for serialization at a quick glance.
 
 trackDuplicateKeys ( $key)
 Track the number of times that a given key has been used.
 

Private Attributes

bool $dupeTrackScheduled = false
 
array $duplicateKeyLookups = []
 
bool $reportDupes = false
 

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.
 
- Public Attributes inherited from Wikimedia\LightweightObjectStore\StorageAwareness
const ATTR_DURABILITY = 2
 Durability of writes; see QOS_DURABILITY_* (higher means stronger)
 
const ATTR_EMULATION = 1
 Emulation/fallback mode; see QOS_EMULATION_*; higher is better.
 
const ERR_NO_RESPONSE = 1
 Storage medium failed to yield a response.
 
const ERR_NONE = 0
 No storage medium error.
 
const ERR_UNEXPECTED = 3
 Storage medium operation failed due to usage limitations or an I/O error.
 
const ERR_UNREACHABLE = 2
 Storage medium could not be reached.
 
const QOS_DURABILITY_DISK = 4
 Data is saved to disk and writes do not usually block on fsync()
 
const QOS_DURABILITY_NONE = 1
 Data is never saved to begin with (blackhole store)
 
const QOS_DURABILITY_RDBMS = 5
 Data is saved to disk and writes usually block on fsync(), like a standard RDBMS.
 
const QOS_DURABILITY_SCRIPT = 2
 Data is lost at the end of the current web request or CLI script.
 
const QOS_DURABILITY_SERVICE = 3
 Data is lost once the service storing the data restarts.
 
const QOS_EMULATION_SQL = 1
 Fallback disk-based SQL store.
 
const QOS_UNKNOWN = INF
 Generic "unknown" value; useful for comparisons (always "good enough")
 

Detailed Description

Storage medium specific cache for storing items (e.g.

redis, memcached, ...)

This should not be used for proxy classes that simply wrap other cache instances

Since
1.34

Definition at line 34 of file MediumSpecificBagOStuff.php.

Constructor & Destructor Documentation

◆ __construct()

MediumSpecificBagOStuff::__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 BagOStuff.

Reimplemented in MemcachedBagOStuff, APCUBagOStuff, EmptyBagOStuff, and WinCacheBagOStuff.

Definition at line 96 of file MediumSpecificBagOStuff.php.

Member Function Documentation

◆ add()

MediumSpecificBagOStuff::add (   $key,
  $value,
  $exptime = 0,
  $flags = 0 
)

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 BagOStuff.

Definition at line 238 of file MediumSpecificBagOStuff.php.

Referenced by MemcLockManager\acquireMutexes().

◆ addBusyCallback()

MediumSpecificBagOStuff::addBusyCallback ( callable  $workCallback)
final

Let a callback be run to avoid wasting time on special blocking calls.

The callbacks may or may not be called ever, in any particular order. They are likely to be invoked when something WRITE_SYNC is used used. They should follow a caching pattern as shown below, so that any code using the work will get it's result no matter what happens.

$result = null;
$workCallback = function () use ( &$result ) {
if ( !$result ) {
$result = ....
}
return $result;
}
Parameters
callable$workCallback
Since
1.28

Reimplemented from BagOStuff.

Definition at line 834 of file MediumSpecificBagOStuff.php.

◆ cas()

MediumSpecificBagOStuff::cas (   $casToken,
  $key,
  $value,
  $exptime = 0,
  $flags = 0 
)
protected

Check and set an item.

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

Definition at line 347 of file MediumSpecificBagOStuff.php.

◆ changeTTL()

MediumSpecificBagOStuff::changeTTL (   $key,
  $exptime = 0,
  $flags = 0 
)

Change the expiration on a key if it exists.

If an expiry in the past is given then the key will immediately be expired

For large values written using WRITE_ALLOW_SEGMENTS, this only changes the TTL of the main segment list key. While lowering the TTL of the segment list key has the effect of functionally lowering the TTL of the key, it might leave unused blobs in cache for longer. Raising the TTL of such keys is not effective, since the expiration of a single segment key effectively expires the entire value.

Parameters
string$key
int$exptimeTTL or UNIX timestamp
int$flagsBitfield of BagOStuff::WRITE_* constants (since 1.33)
Returns
bool Success Returns false on failure or if the item does not exist
Since
1.28

Reimplemented from BagOStuff.

Definition at line 424 of file MediumSpecificBagOStuff.php.

◆ changeTTLMulti()

MediumSpecificBagOStuff::changeTTLMulti ( array  $keys,
  $exptime,
  $flags = 0 
)

Change the expiration of multiple keys that exist.

Parameters
string[]$keysList of keys
int$exptimeTTL or UNIX timestamp
int$flagsBitfield of BagOStuff::WRITE_* constants (since 1.33)
Returns
bool Success
Since
1.34

Reimplemented from BagOStuff.

Definition at line 736 of file MediumSpecificBagOStuff.php.

References $keys.

◆ checkIterableMapSerializability()

MediumSpecificBagOStuff::checkIterableMapSerializability (   $value,
  $key 
)
private
Parameters
array | stdClass$valueResult of the value generation callback for the key
string$keyCache key

Definition at line 1140 of file MediumSpecificBagOStuff.php.

◆ checkValueSerializability()

MediumSpecificBagOStuff::checkValueSerializability (   $value,
  $key 
)
private

Log if a new cache value does not appear suitable for serialization at a quick glance.

This aids migration of values to JSON-like structures and the debugging of exceptions due to serialization failure.

This does not recurse more than one level into container structures.

A proper cache key value is one of the following:

  • null
  • a scalar
  • an array with scalar/null values
  • an array tree with scalar/null "leaf" values
  • an stdClass instance with scalar/null field values
  • an stdClass instance tree with scalar/null "leaf" values
  • an instance of a class that implements JsonSerializable
Parameters
mixed$valueResult of the value generation callback for the key
string$keyCache key

Definition at line 1120 of file MediumSpecificBagOStuff.php.

◆ clearLastError()

MediumSpecificBagOStuff::clearLastError ( )

Clear the "last error" registry.

Since
1.23

Reimplemented from BagOStuff.

Definition at line 821 of file MediumSpecificBagOStuff.php.

◆ convertGenericKey()

MediumSpecificBagOStuff::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 BagOStuff.

Reimplemented in APCUBagOStuff, EmptyBagOStuff, HashBagOStuff, RedisBagOStuff, and RESTBagOStuff.

Definition at line 973 of file MediumSpecificBagOStuff.php.

◆ debug()

◆ delete()

MediumSpecificBagOStuff::delete (   $key,
  $flags = 0 
)

Delete an item.

For large values written using WRITE_ALLOW_SEGMENTS, this only deletes the main segment list key unless WRITE_PRUNE_SEGMENTS is in the flags. While deleting the segment list key has the effect of functionally deleting the key, it leaves unused blobs in cache.

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 BagOStuff.

Definition at line 205 of file MediumSpecificBagOStuff.php.

References doDelete(), doGet(), BagOStuff\fieldHasFlags(), SerializedValueContainer\isSegmented(), makeGlobalKey(), and SerializedValueContainer\SEGMENTED_HASHES.

Referenced by MemcLockManager\releaseMutexes().

◆ deleteMulti()

MediumSpecificBagOStuff::deleteMulti ( array  $keys,
  $flags = 0 
)

Batch deletion.

This does not support WRITE_ALLOW_SEGMENTS to avoid excessive read I/O

Parameters
string[]$keysList of keys
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool Success
Since
1.33

Reimplemented from BagOStuff.

Definition at line 705 of file MediumSpecificBagOStuff.php.

References $keys.

◆ deleteObjectsExpiringBefore()

MediumSpecificBagOStuff::deleteObjectsExpiringBefore (   $timestamp,
callable  $progress = null,
  $limit = INF,
string  $tag = null 
)

Delete all objects expiring before a certain date.

Parameters
string | int$timestampThe reference date in MW or TS_UNIX format
callable | null$progressOptional, a function which will be called regularly during long-running operations with the percentage progress as the first parameter. [optional]
int$limitMaximum number of keys to delete [default: INF]
string | null$tagTag to purge a single shard only. This is only supported when server tags are used in configuration.
Returns
bool Success; false if unimplemented

Reimplemented from BagOStuff.

Reimplemented in SqlBagOStuff.

Definition at line 610 of file MediumSpecificBagOStuff.php.

◆ doAdd()

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

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 in RedisBagOStuff, APCUBagOStuff, EmptyBagOStuff, HashBagOStuff, MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RESTBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.

◆ doCas()

MediumSpecificBagOStuff::doCas (   $casToken,
  $key,
  $value,
  $exptime = 0,
  $flags = 0 
)
protected

Check and set an item.

Parameters
mixed$casToken
string$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 in MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.

Definition at line 372 of file MediumSpecificBagOStuff.php.

References $success.

◆ doChangeTTL()

MediumSpecificBagOStuff::doChangeTTL (   $key,
  $exptime,
  $flags 
)
protected
Parameters
string$key
int$exptime
int$flags
Returns
bool

Reimplemented in MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RedisBagOStuff, and SqlBagOStuff.

Definition at line 434 of file MediumSpecificBagOStuff.php.

References $blob.

◆ doChangeTTLMulti()

MediumSpecificBagOStuff::doChangeTTLMulti ( array  $keys,
  $exptime,
  $flags = 0 
)
protected
Parameters
string[]$keysList of keys
int$exptimeTTL or UNIX timestamp
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool Success

Reimplemented in RedisBagOStuff, and SqlBagOStuff.

Definition at line 746 of file MediumSpecificBagOStuff.php.

References $keys, and $res.

◆ doDelete()

MediumSpecificBagOStuff::doDelete (   $key,
  $flags = 0 
)
abstractprotected

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 in APCUBagOStuff, EmptyBagOStuff, HashBagOStuff, MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RedisBagOStuff, RESTBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.

Referenced by delete().

◆ doDeleteMulti()

MediumSpecificBagOStuff::doDeleteMulti ( array  $keys,
  $flags = 0 
)
protected
Parameters
string[]$keysList of keys
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool Success

Reimplemented in MemcachedPeclBagOStuff, RedisBagOStuff, and SqlBagOStuff.

Definition at line 718 of file MediumSpecificBagOStuff.php.

References $keys, and $res.

◆ doGet()

MediumSpecificBagOStuff::doGet (   $key,
  $flags = 0,
$casToken = null 
)
abstractprotected
Parameters
string$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 in APCUBagOStuff, EmptyBagOStuff, HashBagOStuff, MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RedisBagOStuff, RESTBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.

Referenced by delete(), and get().

◆ doGetMulti()

MediumSpecificBagOStuff::doGetMulti ( array  $keys,
  $flags = 0 
)
protected

Get an associative array containing the item for each of the keys that have items.

Parameters
string[]$keysList of keys
int$flagsBitfield; supports READ_LATEST [optional]
Returns
array Map of (key => value) for existing keys; preserves the order of $keys

Reimplemented in MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RedisBagOStuff, and SqlBagOStuff.

Definition at line 649 of file MediumSpecificBagOStuff.php.

References $keys, and $res.

◆ doLock()

MediumSpecificBagOStuff::doLock (   $key,
  $timeout,
  $exptime 
)
protected
See also
MediumSpecificBagOStuff::lock()
Parameters
string$key
int$timeoutLock wait timeout; 0 for non-blocking [optional]
int$exptimeLock time-to-live 1 day maximum [optional]
Returns
float|null UNIX timestamp of acquisition; null on failure

Reimplemented in SqlBagOStuff.

Definition at line 503 of file MediumSpecificBagOStuff.php.

◆ doSet()

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

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 in APCUBagOStuff, EmptyBagOStuff, HashBagOStuff, MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RedisBagOStuff, RESTBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.

Referenced by set().

◆ doSetMulti()

MediumSpecificBagOStuff::doSetMulti ( array  $data,
  $exptime = 0,
  $flags = 0 
)
protected
Parameters
mixed[]$dataMap of (key => value)
int$exptimeEither an interval in seconds or a unix timestamp for expiry
int$flagsBitfield of BagOStuff::WRITE_* constants
Returns
bool Success

Reimplemented in MemcachedPeclBagOStuff, RedisBagOStuff, and SqlBagOStuff.

Definition at line 686 of file MediumSpecificBagOStuff.php.

References $res.

◆ doUnlock()

MediumSpecificBagOStuff::doUnlock (   $key)
protected
See also
MediumSpecificBagOStuff::unlock()
Parameters
string$key
Returns
bool Success

Reimplemented in SqlBagOStuff.

Definition at line 577 of file MediumSpecificBagOStuff.php.

◆ get()

MediumSpecificBagOStuff::get (   $key,
  $flags = 0 
)

Get an item with the given key.

If the key includes a deterministic input hash (e.g. the key can only have the correct value) or complete staleness checks are handled by the caller (e.g. nothing relies on the TTL), then the READ_VERIFIED flag should be set. This lets tiered backends know they can safely upgrade a cached value to higher tiers using standard TTLs.

Parameters
string$key
int$flagsBitfield of BagOStuff::READ_* constants [optional]
Returns
mixed Returns false on failure or if the item does not exist

Reimplemented from BagOStuff.

Definition at line 121 of file MediumSpecificBagOStuff.php.

References doGet(), resolveSegments(), and trackDuplicateKeys().

◆ getExpirationAsTimestamp()

MediumSpecificBagOStuff::getExpirationAsTimestamp (   $exptime)
finalprotected

Convert an optionally relative timestamp to an absolute time.

The input value will be cast to an integer and interpreted as follows:

  • zero: no expiry; return zero (e.g. TTL_INDEFINITE)
  • negative: relative TTL; return UNIX timestamp offset by this value
  • positive (< 10 years): relative TTL; return UNIX timestamp offset by this value
  • positive (>= 10 years): absolute UNIX timestamp; return this value
Parameters
int$exptime
Returns
int Expiration timestamp or TTL_INDEFINITE for indefinite
Since
1.34

Definition at line 913 of file MediumSpecificBagOStuff.php.

Referenced by RedisBagOStuff\doChangeTTL(), RedisBagOStuff\doChangeTTLMulti(), HashBagOStuff\doSet(), and SqlBagOStuff\makeNewKeyExpiry().

◆ getExpirationAsTTL()

MediumSpecificBagOStuff::getExpirationAsTTL (   $exptime)
finalprotected

Convert an optionally absolute expiry time to a relative time.

If an absolute time is specified which is in the past, use a short expiry time.

The input value will be cast to an integer and interpreted as follows:

  • zero: no expiry; return zero (e.g. TTL_INDEFINITE)
  • negative: relative TTL; return a short expiry time (1 second)
  • positive (< 10 years): relative TTL; return this value
  • positive (>= 10 years): absolute UNIX timestamp; return offset to current time
Parameters
int$exptime
Returns
int Relative TTL or TTL_INDEFINITE for indefinite
Since
1.34

Definition at line 937 of file MediumSpecificBagOStuff.php.

Referenced by RedisBagOStuff\doAdd(), APCUBagOStuff\doAdd(), WinCacheBagOStuff\doAdd(), RedisBagOStuff\doChangeTTL(), RedisBagOStuff\doChangeTTLMulti(), APCUBagOStuff\doSet(), RedisBagOStuff\doSet(), WinCacheBagOStuff\doSet(), RedisBagOStuff\doSetMulti(), and APCUBagOStuff\incrWithInit().

◆ getLastError()

MediumSpecificBagOStuff::getLastError ( )

Get the "last error" registered; clearLastError() should be called manually.

Returns
int ERR_* constant for the "last error" registry
Since
1.23

Reimplemented from BagOStuff.

Definition at line 813 of file MediumSpecificBagOStuff.php.

◆ getMulti()

MediumSpecificBagOStuff::getMulti ( array  $keys,
  $flags = 0 
)

Get an associative array containing the item for each of the keys that have items.

Parameters
string[]$keysList of keys; can be a map of (unused => key) for convenience
int$flagsBitfield; supports READ_LATEST [optional]
Returns
mixed[] Map of (key => value) for existing keys; preserves the order of $keys

Reimplemented from BagOStuff.

Definition at line 625 of file MediumSpecificBagOStuff.php.

References $keys, and $res.

◆ getQoS()

MediumSpecificBagOStuff::getQoS (   $flag)
Parameters
int$flagATTR_* class constant
Returns
int QOS_* class constant
Since
1.28

Reimplemented from BagOStuff.

Definition at line 985 of file MediumSpecificBagOStuff.php.

◆ getSegmentationSize()

MediumSpecificBagOStuff::getSegmentationSize ( )
Returns
int|float The chunk size, in bytes, of segmented objects (INF for no limit)
Since
1.34

Reimplemented from BagOStuff.

Definition at line 989 of file MediumSpecificBagOStuff.php.

◆ getSegmentedValueMaxSize()

MediumSpecificBagOStuff::getSegmentedValueMaxSize ( )
Returns
int|float Maximum total segmented object size in bytes (INF for no limit)
Since
1.34

Reimplemented from BagOStuff.

Definition at line 993 of file MediumSpecificBagOStuff.php.

◆ getSerialized()

MediumSpecificBagOStuff::getSerialized (   $value,
  $key 
)
protected

Get the serialized form a value, using any applicable prepared value.

See also
BagOStuff::setNewPreparedValues()
Parameters
mixed$value
string$key
Returns
string|int String/integer representation
Since
1.35

Definition at line 1026 of file MediumSpecificBagOStuff.php.

References serialize().

Referenced by RedisBagOStuff\doAdd(), APCUBagOStuff\doAdd(), WinCacheBagOStuff\doAdd(), APCUBagOStuff\doSet(), RedisBagOStuff\doSet(), WinCacheBagOStuff\doSet(), RedisBagOStuff\doSetMulti(), SqlBagOStuff\modifyTableSpecificBlobsForAdd(), SqlBagOStuff\modifyTableSpecificBlobsForCas(), and SqlBagOStuff\modifyTableSpecificBlobsForSet().

◆ guessSerialValueSize()

MediumSpecificBagOStuff::guessSerialValueSize (   $value,
  $depth = 0,
$loops = 0 
)
protected

Estimate the size of a variable once serialized.

Parameters
mixed$value
int$depthCurrent stack depth
int&$loopsNumber of iterable nodes visited
Returns
int|null Size in bytes; null for unsupported variable types
Since
1.35

Definition at line 1056 of file MediumSpecificBagOStuff.php.

Referenced by HashBagOStuff\setNewPreparedValues(), and MemcachedPeclBagOStuff\setNewPreparedValues().

◆ incrWithInit()

MediumSpecificBagOStuff::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 BagOStuff.

Reimplemented in APCUBagOStuff, EmptyBagOStuff, and SqlBagOStuff.

Definition at line 755 of file MediumSpecificBagOStuff.php.

◆ isInteger()

◆ isRelativeExpiration()

MediumSpecificBagOStuff::isRelativeExpiration (   $exptime)
finalprotected
Parameters
int | float$exptime
Returns
bool Whether the expiry is non-infinite, and, negative or not a UNIX timestamp
Since
1.34

Definition at line 896 of file MediumSpecificBagOStuff.php.

Referenced by RedisBagOStuff\doChangeTTL(), RedisBagOStuff\doChangeTTLMulti(), and MemcachedBagOStuff\fixExpiry().

◆ lock()

MediumSpecificBagOStuff::lock (   $key,
  $timeout = 6,
  $exptime = 6,
  $rclass = '' 
)
Parameters
string$key
int$timeout
int$exptime
string$rclass
Returns
bool

Reimplemented from BagOStuff.

Definition at line 467 of file MediumSpecificBagOStuff.php.

Referenced by SqlBagOStuff\newLockingWriteSectionModificationTimestamp().

◆ makeGlobalKey()

MediumSpecificBagOStuff::makeGlobalKey (   $collection,
  $components 
)

Make a cache key for the default keyspace and given components.

See also
IStoreKeyEncoder::makeGlobalKey()
Parameters
string$collectionKey collection name component
string|int...$components Additional, ordered, key components for entity IDs
Returns
string Colon-separated, keyspace-prepended, ordered list of encoded components
Since
1.27

Reimplemented from BagOStuff.

Definition at line 965 of file MediumSpecificBagOStuff.php.

Referenced by delete().

◆ makeKey()

MediumSpecificBagOStuff::makeKey (   $collection,
  $components 
)

Make a cache key for the global keyspace and given components.

See also
IStoreKeyEncoder::makeKey()
Parameters
string$collectionKey collection name component
string|int...$components Additional, ordered, key components for entity IDs
Returns
string Colon-separated, keyspace-prepended, ordered list of encoded components
Since
1.27

Reimplemented from BagOStuff.

Definition at line 969 of file MediumSpecificBagOStuff.php.

◆ makeLockKey()

MediumSpecificBagOStuff::makeLockKey (   $key)
protected
Parameters
string$key
Returns
string

Definition at line 606 of file MediumSpecificBagOStuff.php.

◆ makeValueOrSegmentList()

MediumSpecificBagOStuff::makeValueOrSegmentList (   $key,
  $value,
  $exptime,
  $flags 
)
finalprotected

Determine the entry (inline or segment list) to store under a key to save the value.

Parameters
string$key
mixed$value
int$exptime
int$flags
Returns
array (inline value or segment list, whether the entry is usable)
Since
1.34

Definition at line 848 of file MediumSpecificBagOStuff.php.

References $serialized, SerializedValueContainer\newSegmented(), and SerializedValueContainer\newUnified().

Referenced by set().

◆ merge()

MediumSpecificBagOStuff::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 BagOStuff.

Reimplemented in EmptyBagOStuff.

Definition at line 271 of file MediumSpecificBagOStuff.php.

◆ mergeViaCas()

MediumSpecificBagOStuff::mergeViaCas (   $key,
callable  $callback,
  $exptime,
  $attempts,
  $flags 
)
finalprotected
Parameters
string$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
See also
BagOStuff::merge()

Definition at line 284 of file MediumSpecificBagOStuff.php.

References $success.

◆ resolveSegments()

MediumSpecificBagOStuff::resolveSegments (   $key,
  $mainValue 
)
finalprotected

Get and reassemble the chunks of blob at the given key.

Parameters
string$key
mixed$mainValue
Returns
string|null|bool The combined string, false if missing, null on error

Definition at line 778 of file MediumSpecificBagOStuff.php.

References SerializedValueContainer\isUnified(), SerializedValueContainer\UNIFIED_DATA, and unserialize().

Referenced by get().

◆ serialize()

MediumSpecificBagOStuff::serialize (   $value)
protected
Parameters
mixed$value
Returns
string|int|false String/integer representation
Note
Special handling is usually needed for integers so incr()/decr() work

Reimplemented in MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, and SqlBagOStuff.

Definition at line 1164 of file MediumSpecificBagOStuff.php.

References serialize().

◆ set()

MediumSpecificBagOStuff::set (   $key,
  $value,
  $exptime = 0,
  $flags = 0 
)

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 BagOStuff.

Definition at line 177 of file MediumSpecificBagOStuff.php.

References doSet(), and makeValueOrSegmentList().

◆ setLastError()

MediumSpecificBagOStuff::setLastError (   $err)
protected

Set the "last error" registry.

Parameters
int$errERR_* constant
Since
1.23

Definition at line 830 of file MediumSpecificBagOStuff.php.

Referenced by MemcachedPeclBagOStuff\checkResult(), RedisBagOStuff\getConnection(), RESTBagOStuff\handleError(), RedisBagOStuff\handleException(), and SqlBagOStuff\setAndLogDBError().

◆ setMulti()

MediumSpecificBagOStuff::setMulti ( array  $valueByKey,
  $exptime = 0,
  $flags = 0 
)

Batch insertion/replace.

This does not support WRITE_ALLOW_SEGMENTS to avoid excessive read I/O

Parameters
mixed[]$valueByKeyMap of (key => value)
int$exptimeEither an interval in seconds or a unix timestamp for expiry
int$flagsBitfield of BagOStuff::WRITE_* constants (since 1.33)
Returns
bool Success
Since
1.24

Reimplemented from BagOStuff.

Definition at line 672 of file MediumSpecificBagOStuff.php.

◆ setNewPreparedValues()

MediumSpecificBagOStuff::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 );
$cache
Definition mcc.php:33

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 BagOStuff.

Reimplemented in HashBagOStuff, and MemcachedPeclBagOStuff.

Definition at line 997 of file MediumSpecificBagOStuff.php.

References $serialized, and serialize().

◆ trackDuplicateKeys()

MediumSpecificBagOStuff::trackDuplicateKeys (   $key)
private

Track the number of times that a given key has been used.

Parameters
string$key

Definition at line 131 of file MediumSpecificBagOStuff.php.

Referenced by get().

◆ unlock()

MediumSpecificBagOStuff::unlock (   $key)

Release an advisory lock on a key string.

Parameters
string$key
Returns
bool Success

Reimplemented from BagOStuff.

Definition at line 545 of file MediumSpecificBagOStuff.php.

Referenced by SqlBagOStuff\newLockingWriteSectionModificationTimestamp().

◆ unserialize()

MediumSpecificBagOStuff::unserialize (   $value)
protected
Parameters
string | int | false$value
Returns
mixed Original value or false on error
Note
Special handling is usually needed for integers so incr()/decr() work

Reimplemented in MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, and SqlBagOStuff.

Definition at line 1173 of file MediumSpecificBagOStuff.php.

References unserialize().

Referenced by RESTBagOStuff\decodeBody(), APCUBagOStuff\doGet(), RedisBagOStuff\doGet(), WinCacheBagOStuff\doGet(), and RedisBagOStuff\doGetMulti().

◆ updateOpStats()

MediumSpecificBagOStuff::updateOpStats ( string  $op,
array  $keyInfo 
)
protected
Parameters
string$opOperation name as a MediumSpecificBagOStuff::METRIC_OP_* constant
array<int,string>|array<string,int[]>$keyInfo Key list, if payload sizes are not applicable, otherwise, map of (key => (send payload size, receive payload size)); send and receive sizes are null where not applicable and receive sizes are "false" for keys that were not found during read operations

Definition at line 1191 of file MediumSpecificBagOStuff.php.

Referenced by RedisBagOStuff\decr(), RedisBagOStuff\doAdd(), RedisBagOStuff\doChangeTTL(), RedisBagOStuff\doChangeTTLMulti(), RedisBagOStuff\doDelete(), RESTBagOStuff\doDelete(), RedisBagOStuff\doDeleteMulti(), RedisBagOStuff\doGet(), RESTBagOStuff\doGet(), SqlBagOStuff\doGet(), RedisBagOStuff\doGetMulti(), SqlBagOStuff\doGetMulti(), RedisBagOStuff\doSet(), RESTBagOStuff\doSet(), RedisBagOStuff\doSetMulti(), RedisBagOStuff\incr(), SqlBagOStuff\modifyTableSpecificBlobsForAdd(), SqlBagOStuff\modifyTableSpecificBlobsForCas(), SqlBagOStuff\modifyTableSpecificBlobsForChangeTTL(), SqlBagOStuff\modifyTableSpecificBlobsForDelete(), SqlBagOStuff\modifyTableSpecificBlobsForIncrInit(), and SqlBagOStuff\modifyTableSpecificBlobsForSet().

Member Data Documentation

◆ $busyCallbacks

callable [] MediumSpecificBagOStuff::$busyCallbacks = []
protected

Definition at line 54 of file MediumSpecificBagOStuff.php.

Referenced by SqlBagOStuff\waitForReplication().

◆ $dupeTrackScheduled

bool MediumSpecificBagOStuff::$dupeTrackScheduled = false
private

Definition at line 51 of file MediumSpecificBagOStuff.php.

◆ $duplicateKeyLookups

array MediumSpecificBagOStuff::$duplicateKeyLookups = []
private

Definition at line 47 of file MediumSpecificBagOStuff.php.

◆ $lastError

int MediumSpecificBagOStuff::$lastError = self::ERR_NONE
protected

ERR_* class constant.

Definition at line 38 of file MediumSpecificBagOStuff.php.

◆ $locks

array<string,array> MediumSpecificBagOStuff::$locks = []
protected

Map of (key => (class, depth, expiry)

Definition at line 36 of file MediumSpecificBagOStuff.php.

◆ $preparedValues

array [] MediumSpecificBagOStuff::$preparedValues = []
protected

Map of (key => (PHP variable value, serialized value))

Definition at line 57 of file MediumSpecificBagOStuff.php.

◆ $reportDupes

bool MediumSpecificBagOStuff::$reportDupes = false
private

Definition at line 49 of file MediumSpecificBagOStuff.php.

◆ $segmentationSize

int MediumSpecificBagOStuff::$segmentationSize
protected

Bytes; chunk size of segmented cache values.

Definition at line 42 of file MediumSpecificBagOStuff.php.

◆ $segmentedValueMaxSize

int MediumSpecificBagOStuff::$segmentedValueMaxSize
protected

Bytes; maximum total size of a segmented cache value.

Definition at line 44 of file MediumSpecificBagOStuff.php.

◆ $syncTimeout

int MediumSpecificBagOStuff::$syncTimeout
protected

Seconds.

Definition at line 40 of file MediumSpecificBagOStuff.php.

Referenced by SqlBagOStuff\waitForReplication().

◆ LOCK_DEPTH

const MediumSpecificBagOStuff::LOCK_DEPTH = 1
protected

Definition at line 75 of file MediumSpecificBagOStuff.php.

◆ LOCK_EXPIRY

const MediumSpecificBagOStuff::LOCK_EXPIRY = 3
protected

Definition at line 77 of file MediumSpecificBagOStuff.php.

◆ LOCK_RCLASS

const MediumSpecificBagOStuff::LOCK_RCLASS = 0
protected

Definition at line 74 of file MediumSpecificBagOStuff.php.

◆ LOCK_TIME

const MediumSpecificBagOStuff::LOCK_TIME = 2
protected

Definition at line 76 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_ADD

const MediumSpecificBagOStuff::METRIC_OP_ADD = 'add'
protected

Definition at line 69 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_CAS

const MediumSpecificBagOStuff::METRIC_OP_CAS = 'cas'
protected

Definition at line 72 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_CHANGE_TTL

const MediumSpecificBagOStuff::METRIC_OP_CHANGE_TTL = 'change_ttl'
protected

Definition at line 68 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_DECR

const MediumSpecificBagOStuff::METRIC_OP_DECR = 'decr'
protected

Definition at line 71 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_DELETE

const MediumSpecificBagOStuff::METRIC_OP_DELETE = 'delete'
protected

Definition at line 67 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_GET

const MediumSpecificBagOStuff::METRIC_OP_GET = 'get'
protected

Definition at line 65 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_INCR

const MediumSpecificBagOStuff::METRIC_OP_INCR = 'incr'
protected

Definition at line 70 of file MediumSpecificBagOStuff.php.

◆ METRIC_OP_SET

const MediumSpecificBagOStuff::METRIC_OP_SET = 'set'
protected

Definition at line 66 of file MediumSpecificBagOStuff.php.


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