Class to handle enqueueing and running of background jobs. More...

Inheritance diagram for JobQueue:

Collaboration diagram for JobQueue:

Public Member Functions
	ack (Job $job)
	Acknowledge that a job was completed. More...

	batchPush (array $jobs, $flags=0)
	Push a batch of jobs into the queue. More...

	deduplicateRootJob (IJobSpecification $job)
	Register the "root job" of a given job into the queue for de-duplication. More...

	delayedJobsEnabled ()

	delete ()
	Deleted all unclaimed and delayed jobs from the queue. More...

	flushCaches ()
	Clear any process and persistent caches. More...

	getAbandonedCount ()
	Get the number of acquired jobs that can no longer be attempted. More...

	getAcquiredCount ()
	Get the number of acquired jobs (these are temporarily out of the queue). More...

	getAllAbandonedJobs ()
	Get an iterator to traverse over all abandoned jobs in this queue. More...

	getAllAcquiredJobs ()
	Get an iterator to traverse over all claimed jobs in this queue. More...

	getAllDelayedJobs ()
	Get an iterator to traverse over all delayed jobs in this queue. More...

	getAllQueuedJobs ()
	Get an iterator to traverse over all available jobs in this queue. More...

	getCoalesceLocationInternal ()
	Do not use this function outside of JobQueue/JobQueueGroup. More...

	getDelayedCount ()
	Get the number of delayed jobs (these are temporarily out of the queue). More...

	getOrder ()

	getReadOnlyReason ()

	getSiblingQueueSizes (array $types)
	Check the size of each of the given queues. More...

	getSiblingQueuesWithJobs (array $types)
	Check whether each of the given queues are empty. More...

	getSize ()
	Get the number of available (unacquired, non-delayed) jobs in the queue. More...

	getType ()

	getWiki ()

	isEmpty ()
	Quickly check if the queue has no available (unacquired, non-delayed) jobs. More...

	pop ()
	Pop a job off of the queue. More...

	push ($jobs, $flags=0)
	Push one or more jobs into the queue. More...

	waitForBackups ()
	Wait for any replica DBs or backup servers to catch up. More...

Static Public Member Functions
static	factory (array $params)
	Get a job queue object of the specified type. More...

static	incrStats ($key, $type, $delta=1)
	Call wfIncrStats() for the queue overall and for the queue type. More...

Public Attributes
const	QOS_ATOMIC = 1

const	ROOTJOB_TTL = 2419200

Protected Member Functions
	__construct (array $params)

	assertNotReadOnly ()

	doAck (Job $job)

	doBatchPush (array $jobs, $flags)

	doDeduplicateRootJob (IJobSpecification $job)

	doDelete ()

	doFlushCaches ()

	doGetAbandonedCount ()

	doGetAcquiredCount ()

	doGetDelayedCount ()

	doGetSiblingQueueSizes (array $types)

	doGetSiblingQueuesWithJobs (array $types)

	doGetSize ()

	doIsEmpty ()

	doIsRootJobOldDuplicate (Job $job)

	doPop ()

	doWaitForBackups ()

	getRootJobCacheKey ($signature)

	isRootJobOldDuplicate (Job $job)
	Check if the "root" job of a given job has been superseded by a newer one. More...

	optimalOrder ()
	Get the default queue order to use if configuration does not specify one. More...

	supportedOrders ()
	Get the allowed queue orders for configuration validation. More...

	supportsDelayedJobs ()
	Find out if delayed jobs are supported for configuration validation. More...

Protected Attributes
JobQueueAggregator	$aggr

int	$claimTTL
	Time to live in seconds. More...

BagOStuff	$dupCache

int	$maxTries
	Maximum number of times to try a job. More...

string	$order
	Job priority for pop() More...

string bool	$readOnlyReason
	Read only rationale (or false if r/w) More...

string	$type
	Job type. More...

string	$wiki
	Wiki ID. More...

Detailed Description

Class to handle enqueueing and running of background jobs.

Since: 1.21

Definition at line 31 of file JobQueue.php.

Constructor & Destructor Documentation

JobQueue::__construct ( array $params )

protected

Parameters

array $params

Exceptions

MWException

Definition at line 58 of file JobQueue.php.

References CACHE_ANYTHING, optimalOrder(), order, supportedOrders(), type, wfGetCache(), and wiki.

Member Function Documentation

JobQueue::ack ( Job $job )

final

Acknowledge that a job was completed.

This does nothing for certain queue classes or if "claimTTL" is not set. Outside callers should use JobQueueGroup::ack() instead of this function.

Parameters

Job $job

Returns: void

Exceptions

MWException

Definition at line 407 of file JobQueue.php.

References $type, assertNotReadOnly(), doAck(), and Job\getType().

JobQueue::assertNotReadOnly ( )

protected

Exceptions

JobQueueReadOnlyError

Definition at line 695 of file JobQueue.php.

Referenced by ack(), batchPush(), deduplicateRootJob(), delete(), and pop().

JobQueue::batchPush	(	array	$jobs,
			$flags = `0`
	)

final

Push a batch of jobs into the queue.

This does not require $wgJobClasses to be set for the given job type. Outside callers should use JobQueueGroup::push() instead of this function.

Parameters

	IJobSpecification[]	$jobs
int	$flags	Bitfield (supports JobQueue::QOS_ATOMIC)

Returns: void

Exceptions

MWException

Definition at line 319 of file JobQueue.php.

References $flags, $job, $type, as, assertNotReadOnly(), deduplicateRootJob(), doBatchPush(), supportsDelayedJobs(), type, and wiki.

Referenced by push().

JobQueue::deduplicateRootJob ( IJobSpecification $job )

final

Register the "root job" of a given job into the queue for de-duplication.

This should only be called right after all the new jobs have been inserted. This is used to turn older, duplicate, job entries into no-ops. The root job information will remain in the registry until it simply falls out of cache.

This requires that $job has two special fields in the "params" array:

rootJobSignature : hash (e.g. SHA1) that identifies the task
rootJobTimestamp : TS_MW timestamp of this instance of the task

A "root job" is a conceptual job that consist of potentially many smaller jobs that are actually inserted into the queue. For example, "refreshLinks" jobs are spawned when a template is edited. One can think of the task as "update links of pages that use template X" and an instance of that task as a "root job". However, what actually goes into the queue are range and leaf job subtypes. Since these jobs include things like page ID ranges and DB master positions, and can morph into smaller jobs recursively, simple duplicate detection for individual jobs being identical (like that of job_sha1) is not useful.

In the case of "refreshLinks", if these jobs are still in the queue when the template is edited again, we want all of these old refreshLinks jobs for that template to become no-ops. This can greatly reduce server load, since refreshLinks jobs involves parsing. Essentially, the new batch of jobs belong to a new "root job" and the older ones to a previous "root job" for the same task of "update links of pages that use template X".

This does nothing for certain queue classes.

Parameters

IJobSpecification $job

Exceptions

MWException

Returns: bool

Definition at line 453 of file JobQueue.php.

References $type, assertNotReadOnly(), doDeduplicateRootJob(), and IJobSpecification\getType().

Referenced by batchPush().

JobQueue::delayedJobsEnabled ( )

final

Returns: bool Whether delayed jobs are enabled

Since: 1.22

Definition at line 169 of file JobQueue.php.

References supportsDelayedJobs().

JobQueue::delete ( )

final

Deleted all unclaimed and delayed jobs from the queue.

Exceptions

JobQueueError

Since: 1.22

Returns: void

Definition at line 541 of file JobQueue.php.

References assertNotReadOnly(), and doDelete().

JobQueue::doAck ( Job $job )

abstractprotected

See also: JobQueue::ack()

Parameters

Job $job

Referenced by ack().

JobQueue::doBatchPush	(	array	$jobs,
			$flags
	)

abstractprotected

See also: JobQueue::batchPush()

Parameters

	IJobSpecification[]	$jobs
int	$flags

Referenced by batchPush().

JobQueue::doDeduplicateRootJob ( IJobSpecification $job )

protected

See also: JobQueue::deduplicateRootJob()

Parameters

IJobSpecification $job

Exceptions

MWException

Returns: bool

Definition at line 468 of file JobQueue.php.

References $params, $timestamp, getRootJobCacheKey(), IJobSpecification\getRootJobParams(), IJobSpecification\hasRootJobParams(), and ROOTJOB_TTL.

Referenced by deduplicateRootJob().

JobQueue::doDelete ( )

protected

See also: JobQueue::delete()

Exceptions

MWException

Definition at line 551 of file JobQueue.php.

Referenced by delete().

JobQueue::doFlushCaches ( )

protected

See also: JobQueue::flushCaches()

Returns: void

Definition at line 587 of file JobQueue.php.

Referenced by flushCaches().

JobQueue::doGetAbandonedCount ( )

protected

See also: JobQueue::getAbandonedCount()

Returns: int

Definition at line 290 of file JobQueue.php.

Referenced by getAbandonedCount().

JobQueue::doGetAcquiredCount ( )

abstractprotected

See also: JobQueue::getAcquiredCount()

Returns: int

Referenced by getAcquiredCount().

JobQueue::doGetDelayedCount ( )

protected

See also: JobQueue::getDelayedCount()

Returns: int

Definition at line 267 of file JobQueue.php.

Referenced by getDelayedCount().

JobQueue::doGetSiblingQueueSizes ( array $types )

protected

See also: JobQueue::getSiblingQueuesSize()

Parameters

array $types List of queues types

Returns: array|null (list of queue types) or null if unsupported

Definition at line 688 of file JobQueue.php.

Referenced by getSiblingQueueSizes().

JobQueue::doGetSiblingQueuesWithJobs ( array $types )

protected

See also: JobQueue::getSiblingQueuesWithJobs()

Parameters

array $types List of queues types

Returns: array|null (list of queue types) or null if unsupported

Definition at line 665 of file JobQueue.php.

Referenced by getSiblingQueuesWithJobs().

JobQueue::doGetSize ( )

abstractprotected

See also: JobQueue::getSize()

Returns: int

Referenced by getSize().

JobQueue::doIsEmpty ( )

abstractprotected

See also: JobQueue::isEmpty()

Returns: bool

Referenced by isEmpty().

JobQueue::doIsRootJobOldDuplicate ( Job $job )

protected

See also: JobQueue::isRootJobOldDuplicate()

Parameters

Job $job

Returns: bool

Definition at line 510 of file JobQueue.php.

References $params, $timestamp, getRootJobCacheKey(), Job\getRootJobParams(), and Job\hasRootJobParams().

Referenced by isRootJobOldDuplicate().

JobQueue::doPop ( )

abstractprotected

See also: JobQueue::pop()

Returns: Job|bool

Referenced by pop().

JobQueue::doWaitForBackups ( )

protected

See also: JobQueue::waitForBackups()

Returns: void

Definition at line 571 of file JobQueue.php.

Referenced by waitForBackups().

static JobQueue::factory ( array $params )

staticfinal

Get a job queue object of the specified type.

$params includes:

class : What job class to use (determines job type)
wiki : wiki ID of the wiki the jobs are for (defaults to current wiki)
type : The name of the job types this queue handles
order : Order that pop() selects jobs, one of "fifo", "timestamp" or "random". If "fifo" is used, the queue will effectively be FIFO. Note that job completion will not appear to be exactly FIFO if there are multiple job runners since jobs can take different times to finish once popped. If "timestamp" is used, the queue will at least be loosely ordered by timestamp, allowing for some jobs to be popped off out of order. If "random" is used, pop() will pick jobs in random order. Note that it may only be weakly random (e.g. a lottery of the oldest X). If "any" is choosen, the queue will use whatever order is the fastest. This might be useful for improving concurrency for job acquisition.
claimTTL : If supported, the queue will recycle jobs that have been popped but not acknowledged as completed after this many seconds. Recycling of jobs simply means re-inserting them into the queue. Jobs can be attempted up to three times before being discarded.
readOnlyReason : Set this to a string to make the queue read-only.

Queue classes should throw an exception if they do not support the options given.

Parameters

array $params

Returns: JobQueue

Exceptions

MWException

Definition at line 108 of file JobQueue.php.

Referenced by JobQueueFederated\__construct(), CopyJobQueue\execute(), JobQueueGroup\get(), JobQueueGroup\getCoalescedQueues(), JobQueueMemoryTest\newJobQueue(), and JobQueueTest\setUp().

JobQueue::flushCaches ( )

final

Clear any process and persistent caches.

Returns: void

Definition at line 579 of file JobQueue.php.

References doFlushCaches().

JobQueue::getAbandonedCount ( )

final

Get the number of acquired jobs that can no longer be attempted.

Queue classes should use caching if they are any slower without memcached.

If caching is used, this number might be out of date for a minute.

Returns: int

Exceptions

JobQueueError

Definition at line 280 of file JobQueue.php.

References $res, and doGetAbandonedCount().

JobQueue::getAcquiredCount ( )

final

Get the number of acquired jobs (these are temporarily out of the queue).

Queue classes should use caching if they are any slower without memcached.

If caching is used, this number might be out of date for a minute.

Returns: int

Exceptions

JobQueueError

Definition at line 235 of file JobQueue.php.

References $res, and doGetAcquiredCount().

Referenced by JobQueueMemory\doAck().

JobQueue::getAllAbandonedJobs ( )

Get an iterator to traverse over all abandoned jobs in this queue.

Returns: Iterator

Exceptions

JobQueueError

Since: 1.25

Definition at line 633 of file JobQueue.php.

JobQueue::getAllAcquiredJobs ( )

Get an iterator to traverse over all claimed jobs in this queue.

Callers should be quick to iterator over it or few results will be returned due to jobs being acknowledged and deleted

Returns: Iterator

Exceptions

JobQueueError

Since: 1.26

Definition at line 622 of file JobQueue.php.

JobQueue::getAllDelayedJobs ( )

Get an iterator to traverse over all delayed jobs in this queue.

Note: results may be stale if the queue is concurrently modified.

Returns: Iterator

Exceptions

JobQueueError

Since: 1.22

Definition at line 608 of file JobQueue.php.

JobQueue::getAllQueuedJobs ( )

abstract

Get an iterator to traverse over all available jobs in this queue.

This does not include jobs that are currently acquired or delayed. Note: results may be stale if the queue is concurrently modified.

Returns: Iterator

Exceptions

JobQueueError

JobQueue::getCoalesceLocationInternal ( )

Do not use this function outside of JobQueue/JobQueueGroup.

Returns: string

Since: 1.22

Definition at line 643 of file JobQueue.php.

JobQueue::getDelayedCount ( )

final

Get the number of delayed jobs (these are temporarily out of the queue).

Queue classes should use caching if they are any slower without memcached.

If caching is used, this number might be out of date for a minute.

Returns: int

Exceptions

JobQueueError

Since: 1.22

Definition at line 257 of file JobQueue.php.

References $res, and doGetDelayedCount().

JobQueue::getOrder ( )

final

Returns: string One of (random, timestamp, fifo, undefined)

Definition at line 138 of file JobQueue.php.

References $order.

JobQueue::getReadOnlyReason ( )

Returns: string|bool Read-only rational or false if r/w

Since: 1.27

Definition at line 177 of file JobQueue.php.

References $readOnlyReason.

JobQueue::getRootJobCacheKey ( $signature )

protected

Parameters

string $signature Hash identifier of the root job

Returns: string

Definition at line 528 of file JobQueue.php.

References list, type, wfForeignMemcKey(), wfSplitWikiID(), and wiki.

Referenced by JobQueueRedis\doDeduplicateRootJob(), doDeduplicateRootJob(), JobQueueDB\doDeduplicateRootJob(), JobQueueRedis\doIsRootJobOldDuplicate(), and doIsRootJobOldDuplicate().

JobQueue::getSiblingQueueSizes ( array $types )

final

Check the size of each of the given queues.

For queues not served by the same store as this one, 0 is returned. This is used for batching checks for queues stored at the same place.

Parameters

array $types List of queues types

Returns: array|null (job type => whether queue is empty) or null if unsupported

Exceptions

MWException

Since: 1.22

Definition at line 679 of file JobQueue.php.

References doGetSiblingQueueSizes().

JobQueue::getSiblingQueuesWithJobs ( array $types )

final

Check whether each of the given queues are empty.

This is used for batching checks for queues stored at the same place.

Parameters

array $types List of queues types

Returns: array|null (list of non-empty queue types) or null if unsupported

Exceptions

MWException

Since: 1.22

Definition at line 656 of file JobQueue.php.

References doGetSiblingQueuesWithJobs().

JobQueue::getSize ( )

final

Get the number of available (unacquired, non-delayed) jobs in the queue.

Queue classes should use caching if they are any slower without memcached.

If caching is used, this number might be out of date for a minute.

Returns: int

Exceptions

JobQueueError

Definition at line 214 of file JobQueue.php.

References $res, and doGetSize().

JobQueue::getType ( )

final

Returns: string Job type that this queue handles

Definition at line 131 of file JobQueue.php.

References $type.

Referenced by JobQueueDB\getAllAcquiredJobs(), and JobQueueDB\getAllQueuedJobs().

JobQueue::getWiki ( )

final

Returns: string Wiki ID

Definition at line 124 of file JobQueue.php.

References $wiki.

static JobQueue::incrStats	(	$key,
		$type,
		$delta = `1`
	)

static

Call wfIncrStats() for the queue overall and for the queue type.

Parameters

string	$key	Event type
string	$type	Job type
int	$delta

Since: 1.22

Definition at line 709 of file JobQueue.php.

References RequestContext\getMain().

Referenced by JobQueueRedis\doAck(), JobQueueDB\doAck(), JobQueueRedis\doBatchPush(), JobQueueDB\doBatchPushInternal(), JobQueueDB\doPop(), JobQueueRedis\doPop(), pop(), and JobQueueDB\recycleAndDeleteStaleJobs().

JobQueue::isEmpty ( )

final

Quickly check if the queue has no available (unacquired, non-delayed) jobs.

Queue classes should use caching if they are any slower without memcached.

If caching is used, this might return false when there are actually no jobs. If pop() is called and returns false then it should correct the cache. Also, calling flushCaches() first prevents this. However, this affect is typically not distinguishable from the race condition between isEmpty() and pop().

Returns: bool

Exceptions

JobQueueError

Definition at line 193 of file JobQueue.php.

References $res, and doIsEmpty().

JobQueue::isRootJobOldDuplicate ( Job $job )

finalprotected

Check if the "root" job of a given job has been superseded by a newer one.

Parameters

Job $job

Exceptions

MWException

Returns: bool

Definition at line 496 of file JobQueue.php.

References $type, doIsRootJobOldDuplicate(), and Job\getType().

Referenced by pop().

JobQueue::optimalOrder ( )

abstractprotected

Get the default queue order to use if configuration does not specify one.

Returns: string One of (random, timestamp, fifo, undefined)

Referenced by __construct().

JobQueue::pop ( )

final

Pop a job off of the queue.

This requires $wgJobClasses to be set for the given job type. Outside callers should use JobQueueGroup::pop() instead of this function.

Exceptions

MWException

Returns: Job|bool Returns false if there are no jobs

Definition at line 361 of file JobQueue.php.

References $e, $job, assertNotReadOnly(), doPop(), global, incrStats(), isRootJobOldDuplicate(), DuplicateJob\newFromJob(), type, wfWikiID(), and wiki.

JobQueue::push	(	$jobs,
		$flags = `0`
	)

final

Push one or more jobs into the queue.

This does not require $wgJobClasses to be set for the given job type. Outside callers should use JobQueueGroup::push() instead of this function.

Parameters

	IJobSpecification\|IJobSpecification[]	$jobs
int	$flags	Bitfield (supports JobQueue::QOS_ATOMIC)

Returns: void

Exceptions

JobQueueError

Definition at line 304 of file JobQueue.php.

References $flags, and batchPush().

Referenced by CopyJobQueue\copyJobs().

JobQueue::supportedOrders ( )

abstractprotected

Get the allowed queue orders for configuration validation.

Returns: array Subset of (random, timestamp, fifo, undefined)

Referenced by __construct().

JobQueue::supportsDelayedJobs ( )

protected

Find out if delayed jobs are supported for configuration validation.

Returns: bool Whether delayed jobs are supported

Definition at line 161 of file JobQueue.php.

Referenced by batchPush(), and delayedJobsEnabled().

JobQueue::waitForBackups ( )

final

Wait for any replica DBs or backup servers to catch up.

This does nothing for certain queue classes.

Returns: void

Exceptions

JobQueueError

Definition at line 563 of file JobQueue.php.

References doWaitForBackups().

Referenced by CopyJobQueue\copyJobs().

Member Data Documentation

JobQueueAggregator JobQueue::$aggr

protected

Definition at line 48 of file JobQueue.php.

int JobQueue::$claimTTL

protected

Time to live in seconds.

Definition at line 39 of file JobQueue.php.

BagOStuff JobQueue::$dupCache

protected

Definition at line 46 of file JobQueue.php.

Referenced by JobQueueDB\doDeduplicateRootJob().

int JobQueue::$maxTries

protected

Maximum number of times to try a job.

Definition at line 41 of file JobQueue.php.

string JobQueue::$order

protected

Job priority for pop()

Definition at line 37 of file JobQueue.php.

Referenced by getOrder().

string bool JobQueue::$readOnlyReason

protected

Read only rationale (or false if r/w)

Definition at line 43 of file JobQueue.php.

Referenced by getReadOnlyReason().

string JobQueue::$type

protected

Job type.

Definition at line 35 of file JobQueue.php.

Referenced by ack(), batchPush(), JobQueueDB\claimRandom(), deduplicateRootJob(), JobQueueDB\doFlushCaches(), JobQueueFederated\doGetSiblingQueueSizes(), JobQueueRedis\doGetSiblingQueueSizes(), JobQueueMemory\getQueueData(), JobQueueRedis\getQueueKey(), getType(), isRootJobOldDuplicate(), and JobQueueDB\recycleAndDeleteStaleJobs().

string JobQueue::$wiki

protected

Wiki ID.

Definition at line 33 of file JobQueue.php.

Referenced by JobQueueFederated\__construct(), JobQueueMemory\getQueueData(), and getWiki().

const JobQueue::QOS_ATOMIC = 1

Definition at line 50 of file JobQueue.php.

const JobQueue::ROOTJOB_TTL = 2419200

Definition at line 52 of file JobQueue.php.

Referenced by doDeduplicateRootJob(), and JobQueueDB\doDeduplicateRootJob().

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

includes/jobqueue/JobQueue.php

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation