Wikimedia\Rdbms\LoadBalancerSingle Class Reference

Trivial LoadBalancer that always returns an injected connection handle. More...

Inheritance diagram for Wikimedia\Rdbms\LoadBalancerSingle:

Collaboration diagram for Wikimedia\Rdbms\LoadBalancerSingle:

Public Member Functions
	__construct (array $params)
	You probably want to use newFromConnection instead.
	__destruct ()
Public Member Functions inherited from Wikimedia\Rdbms\LoadBalancer
	allowLagged ( $mode=null)
	Disables/enables lag checks.
	approveMasterChanges (array $options, $fname=__METHOD__, $owner=null)
	approvePrimaryChanges (array $options, $fname=__METHOD__, $owner=null)
	Perform all pre-commit checks for things like replication safety.
	beginMasterChanges ( $fname=__METHOD__, $owner=null)
	beginPrimaryChanges ( $fname=__METHOD__, $owner=null)
	Flush any primary transaction snapshots and set DBO_TRX (if DBO_DEFAULT is set)
	closeAll ( $fname=__METHOD__, $owner=null)
	Close all open connections.
	closeConnection (IDatabase $conn)
	Close a connection.
	commitAll ( $fname=__METHOD__, $owner=null)
	Commit transactions on all open connections.
	commitMasterChanges ( $fname=__METHOD__, $owner=null)
	commitPrimaryChanges ( $fname=__METHOD__, $owner=null)
	Issue COMMIT on all open primary connections to flush changes and view snapshots.
	disable ( $fname=__METHOD__, $owner=null)
	Close all connections and disable this load balancer.
	finalizeMasterChanges ( $fname=__METHOD__, $owner=null)
	finalizePrimaryChanges ( $fname=__METHOD__, $owner=null)
	Run pre-commit callbacks and defer execution of post-commit callbacks.
	flushMasterSnapshots ( $fname=__METHOD__, $owner=null)
	flushPrimarySnapshots ( $fname=__METHOD__, $owner=null)
	Commit all primary DB transactions so as to flush any REPEATABLE-READ or SSI snapshots.
	flushReplicaSnapshots ( $fname=__METHOD__, $owner=null)
	Commit all replica DB transactions so as to flush any REPEATABLE-READ or SSI snapshots.
	forEachOpenConnection ( $callback, array $params=[])
	Call a function with each open connection object.
	forEachOpenMasterConnection ( $callback, array $params=[])
	forEachOpenPrimaryConnection ( $callback, array $params=[])
	Call a function with each open connection object to a primary.
	forEachOpenReplicaConnection ( $callback, array $params=[])
	Call a function with each open replica DB connection object.
	getAnyOpenConnection ( $i, $flags=0)
	Get an existing live handle to the given server index (on any domain)
	getClusterName ()
	Get the logical name of the database cluster.
	getConnection ( $i, $groups=[], $domain=false, $flags=0)
	Get a live handle for a specific or virtual (DB_PRIMARY/DB_REPLICA) server index.
	getConnectionRef ( $i, $groups=[], $domain=false, $flags=0)
	Get a live database handle reference for a server index.
	getLaggedReplicaMode ( $domain=false)
	getLagTimes ( $domain=false)
	Get an estimate of replication lag (in seconds) for each server.
	getLazyConnectionRef ( $i, $groups=[], $domain=false, $flags=0)
	Get a lazy-connecting database handle reference for a server index.
	getLocalDomainID ()
	Get the local (and default) database domain ID of connection handles.
	getMaintenanceConnectionRef ( $i, $groups=[], $domain=false, $flags=0)
	Get a live database handle, suitable for migrations and schema changes, for a server index.
	getMasterPos ()
	getMaxLag ( $domain=false)
	Get the name and lag time of the most-lagged replica server.
	getPrimaryPos ()
	Get the current primary replication position.
	getReaderIndex ( $group=false, $domain=false)
	Get the specific server index of the reader connection for a given group.
	getReadOnlyReason ( $domain=false)
	getReplicaResumePos ()
	Get the highest DB replication position for chronology control purposes.
	getServerAttributes ( $i)
	Get basic attributes of the server with the specified index without connecting.
	getServerConnection ( $i, $domain, $flags=0)
	Get a live handle for a specific server index.
	getServerCount ()
	Get the number of servers defined in configuration.
	getServerInfo ( $i)
	Return the server configuration map for the server with the specified index.
	getServerName ( $i)
	Get the readable name of the server with the specified index.
	getServerType ( $i)
	Get the RDBMS type of the server with the specified index (e.g.
	getTransactionRoundStage ()
	getWriterIndex ()
	Get the specific server index of the primary server.
	hasMasterChanges ()
	hasMasterConnection ()
	hasOrMadeRecentMasterChanges ( $age=null)
	hasOrMadeRecentPrimaryChanges ( $age=null)
	Check if this load balancer object had any recent or still pending writes issued against it by this PHP thread.
	hasPrimaryChanges ()
	Whether there are pending changes or callbacks in a transaction by this thread.
	hasPrimaryConnection ()
	hasReplicaServers ()
	Whether there are any replica servers configured.
	hasStreamingReplicaServers ()
	Whether any replica servers use streaming replication from the primary server.
	haveIndex ( $i)
	Returns true if the specified index is a valid server index.
	isNonZeroLoad ( $i)
	Returns true if the specified index is valid and has non-zero load.
	laggedReplicaUsed ()
	Checks whether the database for generic connections this request was both:
	lastMasterChangeTimestamp ()
	lastPrimaryChangeTimestamp ()
	Get the timestamp of the latest write query done by this thread.
	openConnection ( $i, $domain=false, $flags=0)
	pendingMasterChangeCallers ()
	pendingPrimaryChangeCallers ()
	Get the list of callers that have pending primary changes.
	pingAll ()
	redefineLocalDomain ( $domain)
	Close all connection and redefine the local domain for testing or schema creation.
	resolveDomainID ( $domain)
	reuseConnection (IDatabase $conn)
	Mark a live handle as being available for reuse under a different database domain.
	rollbackMasterChanges ( $fname=__METHOD__, $owner=null)
	rollbackPrimaryChanges ( $fname=__METHOD__, $owner=null)
	Issue ROLLBACK only on primary, only if queries were done on connection.
	runMasterTransactionIdleCallbacks ( $fname=__METHOD__, $owner=null)
	runMasterTransactionListenerCallbacks ( $fname=__METHOD__, $owner=null)
	runPrimaryTransactionIdleCallbacks ( $fname=__METHOD__, $owner=null)
	Consume and run all pending post-COMMIT/ROLLBACK callbacks and commit dangling transactions.
	runPrimaryTransactionListenerCallbacks ( $fname=__METHOD__, $owner=null)
	Run all recurring post-COMMIT/ROLLBACK listener callbacks.
	safeGetLag (IDatabase $conn)
	Get the lag in seconds for a given connection, or zero if this load balancer does not have replication enabled.
	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.
	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.
	setTempTablesOnlyMode ( $value, $domain)
	Indicate whether the tables on this domain are only temporary tables for testing.
	setTransactionListener ( $name, callable $callback=null)
	Set a callback via IDatabase::setTransactionListener() on all current and future primary connections of this load balancer.
	waitFor ( $pos)
	Set the primary position to reach before the next generic group DB handle query.
	waitForAll ( $pos, $timeout=null)
	Set the primary wait position and wait for ALL replica DBs to catch up to it.
	waitForMasterPos (IDatabase $conn, $pos=false, $timeout=null)
	waitForOne ( $pos, $timeout=null)
	Set the primary wait position and wait for a generic replica DB to catch up to it.
	waitForPrimaryPos (IDatabase $conn, $pos=false, $timeout=null)
	Wait for a replica DB to reach a specified primary position.

Static Public Member Functions
static	newFromConnection (IDatabase $db, array $params=[])

Protected Member Functions
	reallyOpenConnection ( $i, DatabaseDomain $domain, array $lbInfo=[])
	Open a new network connection to a server (uncached)
Protected Member Functions inherited from Wikimedia\Rdbms\LoadBalancer
	getConnLogContext (IDatabase $conn, array $extras=[])
	Create a log context to pass to PSR-3 logger functions.
	getExistingReaderIndex ( $group)
	Get the server index chosen by the load balancer for use with the given query group.
	resolveDomainInstance ( $domain)

Private Attributes
IDatabase	$db

Additional Inherited Members
Public Attributes inherited from Wikimedia\Rdbms\LoadBalancer
const	MAX_LAG_DEFAULT = 6
	Default 'maxLag' when unspecified.
Public Attributes inherited from Wikimedia\Rdbms\ILoadBalancer
const	CONN_INTENT_WRITABLE = 4
	Caller is requesting the primary DB server for possibly writes.
const	CONN_REFRESH_READ_ONLY = 8
	Bypass and update any server-side read-only mode state cache.
const	CONN_SILENCE_ERRORS = 2
	Return null on connection failure instead of throwing an exception.
const	CONN_TRX_AUTOCOMMIT = 1
	DB handle should have DBO_TRX disabled and the caller will leave it as such.
const	DB_MASTER = self::DB_PRIMARY
	Request a primary, write-enabled DB connection.
const	DB_PRIMARY = -2
	Request a primary, write-enabled DB connection.
const	DB_REPLICA = -1
	Request a replica DB connection.
const	DOMAIN_ANY = ''
	Domain specifier when no specific database needs to be selected.
const	GROUP_GENERIC = ''
	The generic query group.
const	STAGE_POSTCOMMIT_CALLBACKS = 'stage-postcommit-callbacks'
	Manager of ILoadBalancer instances is running post-commit callbacks.
const	STAGE_POSTROLLBACK_CALLBACKS = 'stage-postrollback-callbacks'
	Manager of ILoadBalancer instances is running post-rollback callbacks.

Detailed Description

Trivial LoadBalancer that always returns an injected connection handle.

Definition at line 31 of file LoadBalancerSingle.php.

Constructor & Destructor Documentation

__construct()

Wikimedia\Rdbms\LoadBalancerSingle::__construct

(

array

$params

)

You probably want to use newFromConnection instead.

Parameters

array

$params

An associative array with one member: connection: An IDatabase connection object

Reimplemented from Wikimedia\Rdbms\LoadBalancer.

Definition at line 41 of file LoadBalancerSingle.php.

__destruct()

Wikimedia\Rdbms\LoadBalancerSingle::__destruct

(

)

Reimplemented from Wikimedia\Rdbms\LoadBalancer.

Definition at line 88 of file LoadBalancerSingle.php.

Member Function Documentation

newFromConnection()

static Wikimedia\Rdbms\LoadBalancerSingle::newFromConnection ( IDatabase  $db, array  $params = []  )

static

Parameters

IDatabase	$db	Live connection handle
array	$params	Parameter map to LoadBalancerSingle::__constructs()

Returns

LoadBalancerSingle

Since

1.28

Definition at line 76 of file LoadBalancerSingle.php.

References Wikimedia\Rdbms\LoadBalancerSingle\$db, and Wikimedia\Rdbms\IDatabase\getDomainID().

reallyOpenConnection()

Wikimedia\Rdbms\LoadBalancerSingle::reallyOpenConnection (   $i, DatabaseDomain  $domain, array  $lbInfo = []  )

protected

Open a new network connection to a server (uncached)

Returns a Database object whether or not the connection was successful.

Parameters

int	$i	Specific server index
DatabaseDomain	$domain	Domain the connection is for, possibly unspecified
array	$lbInfo	Additional information for setLBInfo()

Returns

IDatabase

Exceptions

DBAccessError
InvalidArgumentException

Reimplemented from Wikimedia\Rdbms\LoadBalancer.

Definition at line 84 of file LoadBalancerSingle.php.

References Wikimedia\Rdbms\LoadBalancerSingle\$db.

Member Data Documentation

$db

IDatabase Wikimedia\Rdbms\LoadBalancerSingle::$db

private

Definition at line 33 of file LoadBalancerSingle.php.

Referenced by Wikimedia\Rdbms\LoadBalancerSingle\newFromConnection(), and Wikimedia\Rdbms\LoadBalancerSingle\reallyOpenConnection().

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

• includes/libs/rdbms/loadbalancer/LoadBalancerSingle.php