MediaWiki  1.28.0
ILoadBalancer.php
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1 <?php
75 interface ILoadBalancer {
77  const DB_REPLICA = -1;
79  const DB_MASTER = -2;
80 
82  const DOMAIN_ANY = '';
83 
107  public function __construct( array $params );
108 
120  public function getReaderIndex( $group = false, $domain = false );
121 
128  public function waitFor( $pos );
129 
139  public function waitForOne( $pos, $timeout = null );
140 
147  public function waitForAll( $pos, $timeout = null );
148 
156  public function getAnyOpenConnection( $i );
157 
169  public function getConnection( $i, $groups = [], $domain = false );
170 
179  public function reuseConnection( $conn );
180 
193  public function getConnectionRef( $db, $groups = [], $domain = false );
194 
207  public function getLazyConnectionRef( $db, $groups = [], $domain = false );
208 
224  public function openConnection( $i, $domain = false );
225 
229  public function getWriterIndex();
230 
237  public function haveIndex( $i );
238 
245  public function isNonZeroLoad( $i );
246 
252  public function getServerCount();
253 
260  public function getServerName( $i );
261 
267  public function getServerInfo( $i );
268 
275  public function setServerInfo( $i, array $serverInfo );
276 
281  public function getMasterPos();
282 
287  public function disable();
288 
292  public function closeAll();
293 
302  public function closeConnection( IDatabase $conn );
303 
309  public function commitAll( $fname = __METHOD__ );
310 
317  public function finalizeMasterChanges();
318 
328  public function approveMasterChanges( array $options );
329 
342  public function beginMasterChanges( $fname = __METHOD__ );
343 
349  public function commitMasterChanges( $fname = __METHOD__ );
350 
359  public function runMasterPostTrxCallbacks( $type );
360 
366  public function rollbackMasterChanges( $fname = __METHOD__ );
367 
375  public function suppressTransactionEndCallbacks();
376 
382  public function flushReplicaSnapshots( $fname = __METHOD__ );
383 
387  public function hasMasterConnection();
388 
393  public function hasMasterChanges();
394 
399  public function lastMasterChangeTimestamp();
400 
408  public function hasOrMadeRecentMasterChanges( $age = null );
409 
415  public function pendingMasterChangeCallers();
416 
422  public function getLaggedReplicaMode( $domain = false );
423 
428  public function laggedReplicaUsed();
429 
436  public function getReadOnlyReason( $domain = false, IDatabase $conn = null );
437 
443  public function allowLagged( $mode = null );
444 
448  public function pingAll();
449 
455  public function forEachOpenConnection( $callback, array $params = [] );
456 
462  public function forEachOpenMasterConnection( $callback, array $params = [] );
463 
469  public function forEachOpenReplicaConnection( $callback, array $params = [] );
470 
481  public function getMaxLag( $domain = false );
482 
493  public function getLagTimes( $domain = false );
494 
509  public function safeGetLag( IDatabase $conn );
510 
521  public function safeWaitForMasterPos( IDatabase $conn, $pos = false, $timeout = null );
522 
530  public function setTransactionListener( $name, callable $callback = null );
531 
537  public function setDomainPrefix( $prefix );
538 
551  public function setTableAliases( array $aliases );
552 }
runMasterPostTrxCallbacks($type)
Issue all pending post-COMMIT/ROLLBACK callbacks.
setTableAliases(array $aliases)
Make certain table names use their own database, schema, and table prefix when passed into SQL querie...
the array() calling protocol came about after MediaWiki 1.4rc1.
forEachOpenConnection($callback, array $params=[])
Call a function with each open connection object.
reuseConnection($conn)
Mark a foreign connection as being available for reuse under a different DB name or prefix...
getMasterPos()
Get the current master position for chronology control purposes.
flushReplicaSnapshots($fname=__METHOD__)
Commit all replica DB transactions so as to flush any REPEATABLE-READ or SSI snapshot.
beginMasterChanges($fname=__METHOD__)
Flush any master transaction snapshots and set DBO_TRX (if DBO_DEFAULT is set)
lastMasterChangeTimestamp()
Get the timestamp of the latest write query done by this thread.
getAnyOpenConnection($i)
Get any open connection to a given server index, local or foreign Returns false if there is no connec...
__construct(array $params)
Construct a manager of IDatabase connection objects.
const DB_MASTER
Definition: defines.php:23
safeWaitForMasterPos(IDatabase $conn, $pos=false, $timeout=null)
Wait for a replica DB to reach a specified master position.
waitFor($pos)
Set the master wait position If a DB_REPLICA connection has been opened already, waits Otherwise sets...
closeConnection(IDatabase $conn)
Close a connection.
commitAll($fname=__METHOD__)
Commit transactions on all open connections.
getServerInfo($i)
Return the server info structure for a given index, or false if the index is invalid.
waitForAll($pos, $timeout=null)
Set the master wait position and wait for ALL replica DBs to catch up to it.
getLaggedReplicaMode($domain=false)
hasMasterChanges()
Determine if there are pending changes in a transaction by this thread.
getReadOnlyReason($domain=false, IDatabase $conn=null)
setServerInfo($i, array $serverInfo)
Sets the server info structure for the given index.
haveIndex($i)
Returns true if the specified index is a valid server index.
closeAll()
Close all open connections.
getMaxLag($domain=false)
Get the hostname and lag time of the most-lagged replica DB.
Database cluster connection, tracking, load balancing, and transaction manager interface.
forEachOpenMasterConnection($callback, array $params=[])
Call a function with each open connection object to a master.
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Definition: hooks.txt:1046
getReaderIndex($group=false, $domain=false)
Get the index of the reader connection, which may be a replica DB This takes into account load ratios...
$params
pendingMasterChangeCallers()
Get the list of callers that have pending master changes.
isNonZeroLoad($i)
Returns true if the specified index is valid and has non-zero load.
setTransactionListener($name, callable $callback=null)
Set a callback via IDatabase::setTransactionListener() on all current and future master connections o...
forEachOpenReplicaConnection($callback, array $params=[])
Call a function with each open replica DB connection object.
safeGetLag(IDatabase $conn)
Get the lag in seconds for a given connection, or zero if this load balancer does not have replicatio...
getServerCount()
Get the number of defined servers (not the number of open connections)
approveMasterChanges(array $options)
Perform all pre-commit checks for things like replication safety.
getLazyConnectionRef($db, $groups=[], $domain=false)
Get a database connection handle reference without connecting yet.
suppressTransactionEndCallbacks()
Suppress all pending post-COMMIT/ROLLBACK callbacks.
waitForOne($pos, $timeout=null)
Set the master wait position and wait for a "generic" replica DB to catch up to it.
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Definition: injection.txt:35
commitMasterChanges($fname=__METHOD__)
Issue COMMIT on all master connections where writes where done.
if(!defined( 'MEDIAWIKI')) $fname
This file is not a valid entry point, perform no further processing unless MEDIAWIKI is defined...
Definition: Setup.php:36
openConnection($i, $domain=false)
Open a connection to the server given by the specified index Index must be an actual index into the a...
hasOrMadeRecentMasterChanges($age=null)
Check if this load balancer object had any recent or still pending writes issued against it by this P...
getLagTimes($domain=false)
Get an estimate of replication lag (in seconds) for each server.
getConnection($i, $groups=[], $domain=false)
Get a connection by index This is the main entry point for this class.
allowLagged($mode=null)
Disables/enables lag checks.
getConnectionRef($db, $groups=[], $domain=false)
Get a database connection handle reference.
setDomainPrefix($prefix)
Set a new table prefix for the existing local domain ID for testing.
const DB_REPLICA
Definition: defines.php:22
getServerName($i)
Get the host name or IP address of the server with the specified index Prefer a readable name if avai...
finalizeMasterChanges()
Perform all pre-commit callbacks that remain part of the atomic transactions and disable any post-com...
disable()
Disable this load balancer.
rollbackMasterChanges($fname=__METHOD__)
Issue ROLLBACK only on master, only if queries were done on connection.
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Definition: hooks.txt:2491
Basic database interface for live and lazy-loaded relation database handles.
Definition: IDatabase.php:34
Allows to change the fields on the form that will be generated $name
Definition: hooks.txt:300