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Wikimedia\ObjectCache\MemcachedBagOStuff Class Reference

Store data in a memcached server or memcached cluster. More...

Inherits Wikimedia\ObjectCache\MediumSpecificBagOStuff.

Inherited by Wikimedia\ObjectCache\MemcachedPeclBagOStuff, and Wikimedia\ObjectCache\MemcachedPhpBagOStuff.

Collaboration diagram for Wikimedia\ObjectCache\MemcachedBagOStuff:

Public Member Functions

 __construct (array $params)
 
 validateKeyEncoding ( $key)
 Ensure that a key is safe to use (contains no control characters and no characters above the ASCII range.)
 
- Public Member Functions inherited from Wikimedia\ObjectCache\MediumSpecificBagOStuff
 add ( $key, $value, $exptime=0, $flags=0)
 Insert an item if it does not already exist.
 
 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.
 
 delete ( $key, $flags=0)
 Delete an item if it exists.
 
 deleteMulti (array $keys, $flags=0)
 Delete a batch of items.
 
 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.
 
 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, $step=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='')
 
 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.
 
 unlock ( $key)
 Release an advisory lock on a key string.
 
- Public Member Functions inherited from Wikimedia\ObjectCache\BagOStuff
 clearLastError ()
 Clear the "last error" registry.
 
 getCurrentTime ()
 
 getLastError ( $watchPoint=0)
 Get the "last error" registry.
 
 getLogger ()
 
 getScopedLock ( $key, $timeout=6, $exptime=30, $rclass='')
 Get a lightweight exclusive self-unlocking lock.
 
 getWithSetCallback ( $key, $exptime, $callback, $flags=0)
 Get an item, regenerating and setting it if not found.
 
 isKeyGlobal ( $key)
 Check whether a cache key is in the global keyspace.
 
 makeGlobalKey ( $keygroup,... $components)
 Make a cache key from the given components, in the "global" keyspace.
 
 makeKey ( $keygroup,... $components)
 Make a cache key from the given components, in the default keyspace.
 
 setLogger (LoggerInterface $logger)
 
 setMockTime (&$time)
 
 watchErrors ()
 Get a "watch point" token that can be used to get the "last error" to occur after now.
 

Protected Member Functions

 doIncrWithInit ( $key, $exptime, $step, $init, $flags)
 
 doIncrWithInitAsync ( $key, $exptime, $step, $init)
 
 doIncrWithInitSync ( $key, $exptime, $step, $init)
 
 fixExpiry ( $exptime)
 
 makeKeyInternal ( $keyspace, $components)
 Format a cache key.
 
 requireConvertGenericKey ()
 Whether ::proxyCall() must re-encode cache keys before calling read/write methods.
 
 stripRouteFromKey ( $key)
 
 validateKeyAndPrependRoute ( $key)
 
- Protected Member Functions inherited from Wikimedia\ObjectCache\MediumSpecificBagOStuff
 cas ( $casToken, $key, $value, $exptime=0, $flags=0)
 Set an item if the current CAS token matches the provided CAS token.
 
 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)
 Set an item if the current CAS token matches the provided CAS token.
 
 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)
 Get an item.
 
 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, logging a warning if it involves custom classes.
 
 isInteger ( $value)
 Check if a value is an integer.
 
 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.
 
 mergeViaCas ( $key, callable $callback, $exptime, $attempts, $flags)
 
 resolveSegments ( $key, $mainValue)
 Get and reassemble the chunks of blob at the given key.
 
 serialize ( $value)
 
 tokensMatch ( $value, $otherValue)
 
 unserialize ( $value)
 
 updateOpStats (string $op, array $keyInfo)
 
- Protected Member Functions inherited from Wikimedia\ObjectCache\BagOStuff
 fieldHasFlags ( $field, $flags)
 
 mergeFlagMaps (array $bags)
 Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map.
 
 proxyCall (string $method, int $arg0Sig, int $resSig, array $genericArgs, BagOStuff $wrapper)
 Call a method on behalf of wrapper BagOStuff instance.
 
 setLastError ( $error)
 Set the "last error" registry due to a problem encountered during an attempted operation.
 

Protected Attributes

string $routingPrefix
 Routing prefix appended to keys during operations.
 
- Protected Attributes inherited from Wikimedia\ObjectCache\MediumSpecificBagOStuff
array< string, array > $locks = []
 Map of (key => (class LOCK_* constant => value)
 
float $maxLockSendDelay = 0.05
 Seconds; maximum expected seconds for a lock ping to reach the backend.
 
int $segmentationSize
 Bytes; chunk size of segmented cache values.
 
int $segmentedValueMaxSize
 Bytes; maximum total size of a segmented cache value.
 
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.
 
- Protected Attributes inherited from Wikimedia\ObjectCache\BagOStuff
callable null $asyncHandler
 
int[] $attrMap = []
 Map of (BagOStuff:ATTR_* constant => BagOStuff:QOS_* constant)
 
string $keyspace
 Default keyspace; used by makeKey()
 
int $lastError = self::ERR_NONE
 BagOStuff:ERR_* constant of the last error that occurred.
 
int $lastErrorId = 0
 Error event sequence number of the last error that occurred.
 
LoggerInterface $logger
 
StatsFactory $stats
 

Additional Inherited Members

- Public Attributes inherited from Wikimedia\ObjectCache\BagOStuff
const MAX_CONFLICTS_ONE = 1
 Abort after the first merge conflict.
 
const READ_LATEST = 1
 Bitfield constants for get()/getMulti(); these are only advisory.
 
const READ_VERIFIED = 2
 Promise that the caller handles detection of staleness.
 
const WRITE_ALLOW_SEGMENTS = 16
 Allow partitioning of the value if it is a large string.
 
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.
 
const WRITE_CACHE_ONLY = 8
 Bitfield constants for set()/merge(); these are only advisory.
 
const WRITE_PRUNE_SEGMENTS = self::WRITE_ALLOW_SEGMENTS
 Delete all the segments if the value is partitioned.
 
- Public Attributes inherited from Wikimedia\LightweightObjectStore\StorageAwareness
const ATTR_DURABILITY = 2
 Durability of writes; see QOS_DURABILITY_* (higher means stronger)
 
const ATTR_EMULATION = 1
 
const ERR_NO_RESPONSE = 1
 Storage medium failed to yield a complete response to an operation.
 
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 to establish a connection.
 
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_UNKNOWN = INF
 Generic "unknown" value; useful for comparisons (always "good enough")
 
- Static Protected Attributes inherited from Wikimedia\ObjectCache\BagOStuff
static int $nextErrorMonitorId = 1
 Next sequence number to use for watch/error events.
 

Detailed Description

Store data in a memcached server or memcached cluster.

This is a base class for MemcachedPhpBagOStuff and MemcachedPeclBagOStuff.

Definition at line 33 of file MemcachedBagOStuff.php.

Constructor & Destructor Documentation

◆ __construct()

Wikimedia\ObjectCache\MemcachedBagOStuff::__construct ( array $params)
Parameters
array$paramsAdditional 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 Wikimedia\ObjectCache\MediumSpecificBagOStuff.

Definition at line 46 of file MemcachedBagOStuff.php.

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

Member Function Documentation

◆ doIncrWithInit()

Wikimedia\ObjectCache\MemcachedBagOStuff::doIncrWithInit ( $key,
$exptime,
$step,
$init,
$flags )
protected
Parameters
string$key
int$exptime
int$step
int$init
int$flags
Returns
int|bool New value or false on failure

Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.

Definition at line 181 of file MemcachedBagOStuff.php.

◆ doIncrWithInitAsync()

Wikimedia\ObjectCache\MemcachedBagOStuff::doIncrWithInitAsync ( $key,
$exptime,
$step,
$init )
abstractprotected
Parameters
string$key
int$exptime
int$step
int$init
Returns
bool True on success, false on failure

Reimplemented in Wikimedia\ObjectCache\MemcachedPeclBagOStuff, and Wikimedia\ObjectCache\MemcachedPhpBagOStuff.

◆ doIncrWithInitSync()

Wikimedia\ObjectCache\MemcachedBagOStuff::doIncrWithInitSync ( $key,
$exptime,
$step,
$init )
abstractprotected
Parameters
string$key
int$exptime
int$step
int$init
Returns
int|bool New value or false on failure

Reimplemented in Wikimedia\ObjectCache\MemcachedPeclBagOStuff, and Wikimedia\ObjectCache\MemcachedPhpBagOStuff.

◆ fixExpiry()

◆ makeKeyInternal()

Wikimedia\ObjectCache\MemcachedBagOStuff::makeKeyInternal ( $keyspace,
$components )
protected

Format a cache key.

Since
1.27
See also
BagOStuff::makeKeyInternal
Parameters
string$keyspace
string[] | int[]$components
Returns
string

Reimplemented from Wikimedia\ObjectCache\BagOStuff.

Definition at line 67 of file MemcachedBagOStuff.php.

References Wikimedia\ObjectCache\BagOStuff\$keyspace.

◆ requireConvertGenericKey()

Wikimedia\ObjectCache\MemcachedBagOStuff::requireConvertGenericKey ( )
protected

Whether ::proxyCall() must re-encode cache keys before calling read/write methods.

Stability: stable
to override
See also
BagOStuff::makeKeyInternal
BagOStuff::proxyCall
Since
1.41
Returns
bool

Reimplemented from Wikimedia\ObjectCache\BagOStuff.

Definition at line 101 of file MemcachedBagOStuff.php.

◆ stripRouteFromKey()

Wikimedia\ObjectCache\MemcachedBagOStuff::stripRouteFromKey ( $key)
protected

◆ validateKeyAndPrependRoute()

◆ validateKeyEncoding()

Wikimedia\ObjectCache\MemcachedBagOStuff::validateKeyEncoding ( $key)

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

Parameters
string$key
Returns
string
Exceptions
Exception

Definition at line 114 of file MemcachedBagOStuff.php.

Member Data Documentation

◆ $routingPrefix

string Wikimedia\ObjectCache\MemcachedBagOStuff::$routingPrefix
protected

Routing prefix appended to keys during operations.

Definition at line 35 of file MemcachedBagOStuff.php.


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