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

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) More...
 
- Protected Member Functions inherited from Wikimedia\Rdbms\LoadBalancer
 getConnLogContext (IDatabase $conn, array $extras=[])
 Create a log context to pass to PSR-3 logger functions. More...
 
 getExistingReaderIndex ( $group)
 Get the server index chosen by the load balancer for use with the given query group. More...
 
 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. More...
 
- Public Attributes inherited from Wikimedia\Rdbms\ILoadBalancer
const CONN_INTENT_WRITABLE = 4
 Caller is requesting the primary DB server for possibly writes. More...
 
const CONN_REFRESH_READ_ONLY = 8
 Bypass and update any server-side read-only mode state cache. More...
 
const CONN_SILENCE_ERRORS = 2
 Return null on connection failure instead of throwing an exception. More...
 
const CONN_TRX_AUTOCOMMIT = 1
 DB handle should have DBO_TRX disabled and the caller will leave it as such. More...
 
const DB_MASTER = self::DB_PRIMARY
 Request a primary, write-enabled DB connection. More...
 
const DB_PRIMARY = -2
 Request a primary, write-enabled DB connection. More...
 
const DB_REPLICA = -1
 Request a replica DB connection. More...
 
const DOMAIN_ANY = ''
 Domain specifier when no specific database needs to be selected. More...
 
const GROUP_GENERIC = ''
 The generic query group. More...
 
const STAGE_POSTCOMMIT_CALLBACKS = 'stage-postcommit-callbacks'
 Manager of ILoadBalancer instances is running post-commit callbacks. More...
 
const STAGE_POSTROLLBACK_CALLBACKS = 'stage-postrollback-callbacks'
 Manager of ILoadBalancer instances is running post-rollback callbacks. More...
 

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$paramsAn associative array with one member:

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  $params = [] 
)
static
Parameters
IDatabase$dbLive connection handle
array$paramsParameter 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$iSpecific server index
DatabaseDomain$domainDomain the connection is for, possibly unspecified
array$lbInfoAdditional information for setLBInfo()
Returns
Database
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

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