Manager for sites with a single "main" cluster and any number of "external" clusters. More...

Collaboration diagram for Wikimedia\Rdbms\LBFactorySimple:

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Public Member Functions
	__construct (array $conf)

	getAllExternalLBs ()
	Get the tracked load balancer instances for all external clusters.

	getAllMainLBs ()
	Get the tracked load balancer instances for all main clusters.

	getExternalLB ( $cluster)
	Get the tracked load balancer instance for an external cluster.

	getMainLB ( $domain=false)
	Get the tracked load balancer instance for the main cluster that handles the given domain.

	newExternalLB ( $cluster)
	Create a new load balancer instance for an external cluster.

	newMainLB ( $domain=false)
	Create a new load balancer instance for the main cluster that handles the given domain.

Public Member Functions inherited from Wikimedia\Rdbms\LBFactory
	appendShutdownCPIndexAsQuery ( $url, $index)
	Append ?cpPosIndex parameter to a URL for ChronologyProtector purposes if needed.

	autoReconfigure ()
	Reload config using the callback passed defined $config['configCallback'].

	beginPrimaryChanges ( $fname=__METHOD__)
	Flush any primary transaction snapshots and set DBO_TRX (if DBO_DEFAULT is set)

	closeAll ( $fname=__METHOD__)
	Close all connections on instantiated tracked load balancer instances.

	commitAndWaitForReplication ( $fname, $ticket, array $opts=[])
	Commit primary DB transactions and wait for replication (if $ticket indicates it is safe).

	commitPrimaryChanges ( $fname=__METHOD__, int $maxWriteDuration=0)
	Commit changes and clear view snapshots on all primary connections.

	destroy ()
	Close all connections and make further attempts to open connections result in DBAccessError.

	disableChronologyProtection ()
	Disable the ChronologyProtector on all instantiated tracked load balancer instances.

	flushPrimarySessions ( $fname=__METHOD__)
	Release important session-level state (named lock, table locks) as post-rollback cleanup.

	flushReplicaSnapshots ( $fname=__METHOD__)
	Commit all replica database server transactions, clearing any REPEATABLE-READ/SSI snapshots.

	getAllLBs ()
	Get all tracked load balancer instances (generator)

	getChronologyProtectorTouched ( $domain=false)
	Get the UNIX timestamp when the client last touched the DB, if they did so recently.

	getEmptyTransactionTicket ( $fname)
	Get a token asserting that no write transactions are active on tracked connections.

	getLocalDomainID ()
	Get the local (and default) database domain ID of connection handles.

	getPrimaryDatabase ( $domain=false)
	Get connection to the primary database.

	getReplicaDatabase ( $domain=false, $group=null)
	Get connection to a replica database.

	getTransactionProfiler ()
	Get the TransactionProfiler used by this instance.

	hasOrMadeRecentPrimaryChanges ( $age=null)
	Determine if any primary connection has pending/written changes from this request.

	hasPrimaryChanges ()
	Determine if any primary connection has pending changes.

	hasTransactionRound ()
	Check if an explicit transaction round is active.

	isReadyForRoundOperations ()
	Check if transaction rounds can be started, committed, or rolled back right now.

	laggedReplicaUsed ()
	Determine if any lagged replica database server connection was used.

	reconfigure (array $conf)
	Reconfigure using the given config array.

	redefineLocalDomain ( $domain)
	Close all connections and redefine the local database domain.

	resolveDomainID ( $domain)

	rollbackPrimaryChanges ( $fname=__METHOD__)
	Rollback changes on all primary connections.

	setAgentName ( $agent)

	setDefaultReplicationWaitTimeout ( $seconds)
	Set the default timeout for replication wait checks.

	setDomainAliases (array $aliases)
	Convert certain database domains to alternative ones.

	setIndexAliases (array $aliases)
	Convert certain index names to alternative names before querying the DB.

	setLocalDomainPrefix ( $prefix)
	Set a new table prefix for the existing local domain ID for testing.

	setMockTime (&$time)

	setRequestInfo (array $info)
	Inject HTTP request header/cookie information during setup of this instance.

	setTableAliases (array $aliases)
	Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name.

	setWaitForReplicationListener ( $name, callable $callback=null)
	Add a callback to be run in every call to waitForReplication() before waiting.

	shutdown ( $flags=self::SHUTDOWN_NORMAL, callable $workCallback=null, &$cpIndex=null, &$cpClientId=null)
	Prepare all instantiated tracked load balancer instances for shutdown.

	waitForReplication (array $opts=[])
	Waits for the replica database server to catch up to the current primary position.

Protected Member Functions
	getLBsForOwner ()
	Get all tracked load balancers with the internal "for owner" interface.

Protected Member Functions inherited from Wikimedia\Rdbms\LBFactory
	baseLoadBalancerParams ()
	Get parameters to ILoadBalancer::__construct()

	configure (array $conf)

	getChronologyProtector ()

	initLoadBalancer (ILoadBalancerForOwner $lb)

	resolveDomainInstance ( $domain)

	shutdownChronologyProtector (ChronologyProtector $cp, &$cpIndex=null)
	Get and record all of the staged DB positions into persistent memory storage.

Additional Inherited Members
Static Public Member Functions inherited from Wikimedia\Rdbms\LBFactory
static	getCPInfoFromCookieValue (?string $value, int $minTimestamp)
	Parse a string conveying the client and write index of the chronology protector data.

static	makeCookieValueFromCPIndex (int $writeIndex, int $time, string $clientId)
	Build a string conveying the client and write index of the chronology protector data.

Public Attributes inherited from Wikimedia\Rdbms\ILBFactory
const	SHUTDOWN_NO_CHRONPROT = 1
	Do not save "session consistency" DB replication positions.

const	SHUTDOWN_NORMAL = 0
	Idiom for "no special shutdown flags".

Protected Attributes inherited from Wikimedia\Rdbms\LBFactory
BagOStuff	$cpStash

DatabaseFactory	$databaseFactory

DatabaseDomain	$localDomain
	Local domain.

string false	$readOnlyReason = false
	Reason all LBs are read-only or false if not.

BagOStuff	$srvCache

WANObjectCache	$wanCache

Detailed Description

Manager for sites with a single "main" cluster and any number of "external" clusters.

See also: LBFactoryMulti

The class allows for large site farms to split up their data in the following ways:

Vertically shard compact site-specific data by site (e.g. page/comment metadata)
Vertically shard compact global data by module (e.g. account/notification data)
Horizontally shard any bulk data by blob key (e.g. page/comment content)

Definition at line 36 of file LBFactorySimple.php.

Constructor & Destructor Documentation

◆ __construct()

Wikimedia\Rdbms\LBFactorySimple::__construct ( array $conf )

See also: LBFactory::__construct()

Parameters

array

$conf

Additional parameters include:

servers : list of server config maps to Database::factory(). Additionally, the server maps should have a 'load' key, which is used to decide how often clients connect to one server verses the others. A 'max lag' key should also be set on server maps, indicating how stale the data can be before the load balancer tries to avoid using it. The map can have 'is static' set to disable blocking replication sync checks (intended for archive servers with unchanging data).
externalClusters : map of cluster names to server arrays. The servers arrays have the same format as "servers" above.
loadMonitor: LoadMonitor::__construct() parameters with "class" field. [optional]

Reimplemented from Wikimedia\Rdbms\LBFactory.

Definition at line 63 of file LBFactorySimple.php.

Member Function Documentation

◆ getAllExternalLBs()

Wikimedia\Rdbms\LBFactorySimple::getAllExternalLBs ( )

Get the tracked load balancer instances for all external clusters.

If no tracked instance exists for a cluster, then one will be instantiated

Returns: ILoadBalancer[] Map of (cluster name => ILoadBalancer)

Since: 1.29

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 118 of file LBFactorySimple.php.

◆ getAllMainLBs()

Wikimedia\Rdbms\LBFactorySimple::getAllMainLBs ( )

Get the tracked load balancer instances for all main clusters.

If no tracked instance exists for a cluster, then one will be instantiated

Note that default main cluster name is ILoadBalancer::CLUSTER_MAIN_DEFAULT

Returns: ILoadBalancer[] Map of (cluster name => ILoadBalancer)

Since: 1.29

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 114 of file LBFactorySimple.php.

◆ getExternalLB()

Wikimedia\Rdbms\LBFactorySimple::getExternalLB ( $cluster )

Get the tracked load balancer instance for an external cluster.

If no tracked instances exists, then one will be instantiated

Parameters

string $cluster External cluster name

Exceptions

InvalidArgumentException If $cluster is not recognized

Returns: ILoadBalancer

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 106 of file LBFactorySimple.php.

◆ getLBsForOwner()

Wikimedia\Rdbms\LBFactorySimple::getLBsForOwner ( )

protected

Get all tracked load balancers with the internal "for owner" interface.

Most subclasses override this, we just provide an implementation here for the benefit of Wikibase's FakeLBFactory.

Returns: Generator|ILoadBalancerForOwner[]

Reimplemented from Wikimedia\Rdbms\LBFactory.

Definition at line 141 of file LBFactorySimple.php.

◆ getMainLB()

Wikimedia\Rdbms\LBFactorySimple::getMainLB ( $domain = false )

Get the tracked load balancer instance for the main cluster that handles the given domain.

If no tracked instances exists, then one will be instantiated

Note: The local/default database domain used by the load balancer instance will still inherit from this ILBFactory instance, regardless of the $domain parameter.

Parameters

string | false $domain Domain ID, or false for the current domain

Returns: ILoadBalancer

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 89 of file LBFactorySimple.php.

◆ newExternalLB()

Wikimedia\Rdbms\LBFactorySimple::newExternalLB ( $cluster )

Create a new load balancer instance for an external cluster.

The resulting object will be untracked and the caller is responsible for cleaning it up. Database replication positions will not be saved by ChronologyProtector.

This method is for only advanced usage and callers should almost always use getExternalLB() instead. This method can be useful when a table is used as a key/value store. In that cases, one might want to query it in autocommit mode (DBO_TRX off) but still use DBO_TRX transaction rounds on other tables.

Parameters

string $cluster External cluster name

Exceptions

InvalidArgumentException If $cluster is not recognized

Returns: ILoadBalancerForOwner

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 95 of file LBFactorySimple.php.

◆ newMainLB()

Wikimedia\Rdbms\LBFactorySimple::newMainLB ( $domain = false )

Create a new load balancer instance for the main cluster that handles the given domain.

The resulting object will be untracked and the caller is responsible for cleaning it up. Database replication positions will not be saved by ChronologyProtector.

This method is for only advanced usage and callers should almost always use getMainLB() instead. This method can be useful when a table is used as a key/value store. In that cases, one might want to query it in autocommit mode (DBO_TRX off) but still use DBO_TRX transaction rounds on other tables.

Note: The local/default database domain used by the load balancer instance will still inherit from this ILBFactory instance, regardless of the $domain parameter.

Parameters

string | false $domain Domain ID, or false for the current domain

Returns: ILoadBalancerForOwner

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 82 of file LBFactorySimple.php.

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

includes/libs/rdbms/lbfactory/LBFactorySimple.php

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ getAllExternalLBs()

◆ getAllMainLBs()

◆ getExternalLB()

◆ getLBsForOwner()

◆ getMainLB()

◆ newExternalLB()

◆ newMainLB()