rdbms: add replica server counting methods to ILoadBalancer

[lhc/web/wiklou.git] / includes / libs / rdbms / lbfactory / LBFactory.php

diff --git a/includes/libs/rdbms/lbfactory/LBFactory.php b/includes/libs/rdbms/lbfactory/LBFactory.php
index bf10053..e20f6de 100644 (file)
--- a/includes/libs/rdbms/lbfactory/LBFactory.php
+++ b/includes/libs/rdbms/lbfactory/LBFactory.php
@@ -85,7 +85,9 @@ abstract class LBFactory implements ILBFactory {
        /** @var callable[] */
        private $replicationWaitCallbacks = [];
 
-       /** @var mixed */
+       /** var int An identifier for this class instance */
+       private $id;
+       /** @var int|null Ticket used to delegate transaction ownership */
        private $ticket;
        /** @var string|bool String if a requested DBO_TRX transaction round is active */
        private $trxRoundId = false;
@@ -153,6 +155,7 @@ abstract class LBFactory implements ILBFactory {
                $this->defaultGroup = $conf['defaultGroup'] ?? null;
                $this->secret = $conf['secret'] ?? '';
 
+               $this->id = mt_rand();
                $this->ticket = mt_rand();
        }
 
@@ -251,7 +254,7 @@ abstract class LBFactory implements ILBFactory {
                }
                $this->trxRoundId = $fname;
                // Set DBO_TRX flags on all appropriate DBs
-               $this->forEachLBCallMethod( 'beginMasterChanges', [ $fname ] );
+               $this->forEachLBCallMethod( 'beginMasterChanges', [ $fname, $this->id ] );
                $this->trxRoundStage = self::ROUND_CURSORY;
        }
 
@@ -269,17 +272,17 @@ abstract class LBFactory implements ILBFactory {
                // Run pre-commit callbacks and suppress post-commit callbacks, aborting on failure
                do {
                        $count = 0; // number of callbacks executed this iteration
-                       $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$count ) {
-                               $count += $lb->finalizeMasterChanges();
+                       $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$count, $fname ) {
+                               $count += $lb->finalizeMasterChanges( $fname, $this->id );
                        } );
                } while ( $count > 0 );
                $this->trxRoundId = false;
                // Perform pre-commit checks, aborting on failure
-               $this->forEachLBCallMethod( 'approveMasterChanges', [ $options ] );
+               $this->forEachLBCallMethod( 'approveMasterChanges', [ $options, $fname, $this->id ] );
                // Log the DBs and methods involved in multi-DB transactions
                $this->logIfMultiDbTransaction();
                // Actually perform the commit on all master DB connections and revert DBO_TRX
-               $this->forEachLBCallMethod( 'commitMasterChanges', [ $fname ] );
+               $this->forEachLBCallMethod( 'commitMasterChanges', [ $fname, $this->id ] );
                // Run all post-commit callbacks in a separate step
                $this->trxRoundStage = self::ROUND_COMMIT_CALLBACKS;
                $e = $this->executePostTransactionCallbacks();
@@ -294,7 +297,7 @@ abstract class LBFactory implements ILBFactory {
                $this->trxRoundStage = self::ROUND_ROLLING_BACK;
                $this->trxRoundId = false;
                // Actually perform the rollback on all master DB connections and revert DBO_TRX
-               $this->forEachLBCallMethod( 'rollbackMasterChanges', [ $fname ] );
+               $this->forEachLBCallMethod( 'rollbackMasterChanges', [ $fname, $this->id ] );
                // Run all post-commit callbacks in a separate step
                $this->trxRoundStage = self::ROUND_ROLLBACK_CALLBACKS;
                $this->executePostTransactionCallbacks();
@@ -305,17 +308,18 @@ abstract class LBFactory implements ILBFactory {
         * @return Exception|null
         */
        private function executePostTransactionCallbacks() {
+               $fname = __METHOD__;
                // Run all post-commit callbacks until new ones stop getting added
                $e = null; // first callback exception
                do {
-                       $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$e ) {
-                               $ex = $lb->runMasterTransactionIdleCallbacks();
+                       $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$e, $fname ) {
+                               $ex = $lb->runMasterTransactionIdleCallbacks( $fname, $this->id );
                                $e = $e ?: $ex;
                        } );
                } while ( $this->hasMasterChanges() );
                // Run all listener callbacks once
-               $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$e ) {
-                       $ex = $lb->runMasterTransactionListenerCallbacks();
+               $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$e, $fname ) {
+                       $ex = $lb->runMasterTransactionListenerCallbacks( $fname, $this->id );
                        $e = $e ?: $ex;
                } );
 
@@ -412,12 +416,11 @@ abstract class LBFactory implements ILBFactory {
                // time needed to wait on the next clusters.
                $masterPositions = array_fill( 0, count( $lbs ), false );
                foreach ( $lbs as $i => $lb ) {
-                       if ( $lb->getServerCount() <= 1 ) {
-                               // T29975 - Don't try to wait for replica DBs if there are none
-                               // Prevents permission error when getting master position
-                               continue;
-                       } elseif ( $opts['ifWritesSince']
-                               && $lb->lastMasterChangeTimestamp() < $opts['ifWritesSince']
+                       if ( !$lb->hasStreamingReplicaServers() ) {
+                               continue; // T29975: no replication; avoid getMasterPos() permissions errors
+                       } elseif (
+                               $opts['ifWritesSince'] &&
+                               $lb->lastMasterChangeTimestamp() < $opts['ifWritesSince']
                        ) {
                                continue; // no writes since the last wait
                        }
@@ -511,7 +514,7 @@ abstract class LBFactory implements ILBFactory {
                        [
                                'ip' => $this->requestInfo['IPAddress'],
                                'agent' => $this->requestInfo['UserAgent'],
-                               'clientId' => $this->requestInfo['ChronologyClientId']
+                               'clientId' => $this->requestInfo['ChronologyClientId'] ?: null
                        ],
                        $this->requestInfo['ChronologyPositionIndex'],
                        $this->secret
@@ -549,7 +552,7 @@ abstract class LBFactory implements ILBFactory {
        ) {
                // Record all the master positions needed
                $this->forEachLB( function ( ILoadBalancer $lb ) use ( $cp ) {
-                       $cp->shutdownLB( $lb );
+                       $cp->storeSessionReplicationPosition( $lb );
                } );
                // Write them to the persistent stash. Try to do something useful by running $work
                // while ChronologyProtector waits for the stash write to replicate to all DCs.
@@ -603,9 +606,10 @@ abstract class LBFactory implements ILBFactory {
                        'chronologyCallback' => function ( ILoadBalancer $lb ) {
                                // Defer ChronologyProtector construction in case setRequestInfo() ends up
                                // being called later (but before the first connection attempt) (T192611)
-                               $this->getChronologyProtector()->initLB( $lb );
+                               $this->getChronologyProtector()->applySessionReplicationPosition( $lb );
                        },
-                       'roundStage' => $initStage
+                       'roundStage' => $initStage,
+                       'ownerId' => $this->id
                ];
        }
 
@@ -614,7 +618,7 @@ abstract class LBFactory implements ILBFactory {
         */
        protected function initLoadBalancer( ILoadBalancer $lb ) {
                if ( $this->trxRoundId !== false ) {
-                       $lb->beginMasterChanges( $this->trxRoundId ); // set DBO_TRX
+                       $lb->beginMasterChanges( $this->trxRoundId, $this->id ); // set DBO_TRX
                }
 
                $lb->setTableAliases( $this->tableAliases );
@@ -670,7 +674,7 @@ abstract class LBFactory implements ILBFactory {
        public function appendShutdownCPIndexAsQuery( $url, $index ) {
                $usedCluster = 0;
                $this->forEachLB( function ( ILoadBalancer $lb ) use ( &$usedCluster ) {
-                       $usedCluster |= ( $lb->getServerCount() > 1 );
+                       $usedCluster |= $lb->hasStreamingReplicaServers();
                } );
 
                if ( !$usedCluster ) {