Wikimedia\Rdbms\LoadBalancerSingle Class Reference

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

Inherits Wikimedia\Rdbms\LoadBalancer.

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
	approvePrimaryChanges (int $maxWriteDuration, $fname=__METHOD__)
	Perform all pre-commit checks for things like replication safety.
	beginPrimaryChanges ( $fname=__METHOD__)
	Flush any primary transaction snapshots and set DBO_TRX (if DBO_DEFAULT is set)
	closeAll ( $fname=__METHOD__)
	Close all open connections.
	commitPrimaryChanges ( $fname=__METHOD__)
	Issue COMMIT on all open primary connections to flush changes and view snapshots.
	disable ( $fname=__METHOD__)
	Close all connections and disable this load balancer.
	explicitTrxActive ()
	Determine whether an explicit transaction is active on any open primary connection.
	finalizePrimaryChanges ( $fname=__METHOD__)
	Run pre-commit callbacks and defer execution of post-commit callbacks.
	flushPrimarySessions ( $fname=__METHOD__)
	Release/destroy session-level named locks, table locks, and temp tables.
	flushPrimarySnapshots ( $fname=__METHOD__)
	Commit all primary DB transactions so as to flush any REPEATABLE-READ or SSI snapshots.
	flushReplicaSnapshots ( $fname=__METHOD__)
	Commit all replica DB transactions so as to flush any REPEATABLE-READ or SSI snapshots.
	getAnyOpenConnection ( $i, $flags=0)
	getClusterName ()
	Get the name of the overall cluster of database servers managing the dataset.
	getConnection ( $i, $groups=[], $domain=false, $flags=0)
	Get a lazy-connecting database handle for a specific or virtual (DB_PRIMARY/DB_REPLICA) server index.
	getConnectionInternal ( $i, $groups=[], $domain=false, $flags=0)
	getConnectionRef ( $i, $groups=[], $domain=false, $flags=0)
	getLagTimes ()
	Get an estimate of replication lag (in seconds) for each server.
	getLocalDomainID ()
	Get the local (and default) database domain ID of connection handles.
	getMaintenanceConnectionRef ( $i, $groups=[], $domain=false, $flags=0)
	Get a DB handle, suitable for migrations and schema changes, for a server index.
	getMaxLag ()
	Get the name and lag time of the most-lagged replica server.
	getPrimaryPos ()
	Get the current primary replication position.
	getReaderIndex ( $group=false)
	Get the specific server index of the reader connection for a given group.
	getReadOnlyReason ()
	getServerAttributes ( $i)
	Get basic attributes of the server with the specified index without connecting.
	getServerConnection ( $i, $domain, $flags=0)
	Get a DB 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.
	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.
	laggedReplicaUsed ()
	Whether a highly "lagged" replica database connection was queried.
	lastPrimaryChangeTimestamp ()
	Get the timestamp of the latest write query done by this thread.
	pendingPrimaryChangeCallers ()
	Get the list of callers that have pending primary changes.
	pingAll ()
	reconfigure (array $params)
	Apply updated configuration.
	redefineLocalDomain ( $domain)
	Close all connection and redefine the local domain for testing or schema creation.
	resolveDomainID ( $domain)
	rollbackPrimaryChanges ( $fname=__METHOD__)
	Issue ROLLBACK only on primary, only if queries were done on connection.
	runPrimaryTransactionIdleCallbacks ( $fname=__METHOD__)
	Consume and run all pending post-COMMIT/ROLLBACK callbacks and commit dangling transactions.
	runPrimaryTransactionListenerCallbacks ( $fname=__METHOD__)
	Run all recurring post-COMMIT/ROLLBACK listener callbacks.
	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)
	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.
	waitForAll (DBPrimaryPos $pos, $timeout=null)
	Set the primary wait position and wait for ALL replica DBs to catch up to it.
	waitForPrimaryPos (IDatabase $conn)
	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)
	sanitizeConnectionFlags ( $flags, $domain)
	Sanitize connection flags provided by a call to getConnection()
Protected Member Functions inherited from Wikimedia\Rdbms\LoadBalancer
	configure (array $params)
	getConnLogContext (IDatabase $conn, array $extras=[])
	Create a log context to pass to PSR-3 logger functions.
	getExistingReaderIndex ( $group)
	Get the server index chosen for DB_REPLICA connections for the given query group.
	resolveDomainInstance ( $domain)

Additional Inherited Members
Public Attributes inherited from Wikimedia\Rdbms\ILoadBalancerForOwner
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.
Public Attributes inherited from Wikimedia\Rdbms\ILoadBalancer
const	CONN_SILENCE_ERRORS = 4
	Yield null on connection failure instead of throwing an exception.
const	CONN_TRX_AUTOCOMMIT = 1
	Yield a tracked autocommit-mode handle (reuse existing ones)
const	CONN_UNTRACKED_GAUGE = 2
	Yield an untracked, low-timeout, autocommit-mode handle (to gauge server health)
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.

Detailed Description

Trivial LoadBalancer that always returns an injected connection handle.

Definition at line 29 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 39 of file LoadBalancerSingle.php.

References $params, Wikimedia\Rdbms\Database\getDBname(), Wikimedia\Rdbms\Database\getServer(), Wikimedia\Rdbms\IReadableDatabase\getType(), and Wikimedia\Rdbms\Database\setLBInfo().

__destruct()

Wikimedia\Rdbms\LoadBalancerSingle::__destruct

(

)

Definition at line 99 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 74 of file LoadBalancerSingle.php.

References $params, and Wikimedia\Rdbms\IReadableDatabase\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

Database

Exceptions

DBAccessError
InvalidArgumentException

Reimplemented from Wikimedia\Rdbms\LoadBalancer.

Definition at line 91 of file LoadBalancerSingle.php.

sanitizeConnectionFlags()

Wikimedia\Rdbms\LoadBalancerSingle::sanitizeConnectionFlags ( $flags, $domain )

protected

Sanitize connection flags provided by a call to getConnection()

Parameters

int	$flags	Bitfield of class CONN_* constants
string	$domain	Database domain

Returns

int Sanitized bitfield

Reimplemented from Wikimedia\Rdbms\LoadBalancer.

Definition at line 82 of file LoadBalancerSingle.php.

References Wikimedia\Rdbms\ILoadBalancer\CONN_TRX_AUTOCOMMIT.

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

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