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Diffstat (limited to 'www/wiki/includes/libs/rdbms/lbfactory/LBFactorySimple.php')
| -rw-r--r-- | www/wiki/includes/libs/rdbms/lbfactory/LBFactorySimple.php | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/www/wiki/includes/libs/rdbms/lbfactory/LBFactorySimple.php b/www/wiki/includes/libs/rdbms/lbfactory/LBFactorySimple.php new file mode 100644 index 00000000..9a6aa3a7 --- /dev/null +++ b/www/wiki/includes/libs/rdbms/lbfactory/LBFactorySimple.php @@ -0,0 +1,162 @@ +<?php +/** + * Generator of database load balancing objects. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * http://www.gnu.org/copyleft/gpl.html + * + * @file + * @ingroup Database + */ + +namespace Wikimedia\Rdbms; + +use InvalidArgumentException; + +/** + * A simple single-master LBFactory that gets its configuration from the b/c globals + */ +class LBFactorySimple extends LBFactory { + /** @var LoadBalancer */ + private $mainLB; + /** @var LoadBalancer[] */ + private $extLBs = []; + + /** @var array[] Map of (server index => server config) */ + private $servers = []; + /** @var array[] Map of (cluster => (server index => server config)) */ + private $externalClusters = []; + + /** @var string */ + private $loadMonitorClass; + /** @var int */ + private $maxLag; + + /** @var int Default 'maxLag' when unspecified */ + const MAX_LAG_DEFAULT = 10; + + /** + * @see LBFactory::__construct() + * @param array $conf Parameters of LBFactory::__construct() as well as: + * - servers : list of server configuration maps to Database::factory(). + * Additionally, the server maps should have a 'load' key, which is used to decide + * how often clients connect to one server verses the others. A 'max lag' key should + * also be set on server maps, indicating how stale the data can be before the load + * balancer tries to avoid using it. The map can have 'is static' set to disable blocking + * replication sync checks (intended for archive servers with unchanging data). + * - externalClusters : map of cluster names to server arrays. The servers arrays have the + * same format as "servers" above. + */ + public function __construct( array $conf ) { + parent::__construct( $conf ); + + $this->servers = isset( $conf['servers'] ) ? $conf['servers'] : []; + foreach ( $this->servers as $i => $server ) { + if ( $i == 0 ) { + $this->servers[$i]['master'] = true; + } else { + $this->servers[$i]['replica'] = true; + } + } + + $this->externalClusters = isset( $conf['externalClusters'] ) + ? $conf['externalClusters'] + : []; + $this->loadMonitorClass = isset( $conf['loadMonitorClass'] ) + ? $conf['loadMonitorClass'] + : 'LoadMonitor'; + $this->maxLag = isset( $conf['maxLag'] ) ? $conf['maxLag'] : self::MAX_LAG_DEFAULT; + } + + /** + * @param bool|string $domain + * @return LoadBalancer + */ + public function newMainLB( $domain = false ) { + return $this->newLoadBalancer( $this->servers ); + } + + /** + * @param bool|string $domain + * @return LoadBalancer + */ + public function getMainLB( $domain = false ) { + if ( !isset( $this->mainLB ) ) { + $this->mainLB = $this->newMainLB( $domain ); + } + + return $this->mainLB; + } + + public function newExternalLB( $cluster ) { + if ( !isset( $this->externalClusters[$cluster] ) ) { + throw new InvalidArgumentException( __METHOD__ . ": Unknown cluster \"$cluster\"." ); + } + + return $this->newLoadBalancer( $this->externalClusters[$cluster] ); + } + + public function getExternalLB( $cluster ) { + if ( !isset( $this->extLBs[$cluster] ) ) { + $this->extLBs[$cluster] = $this->newExternalLB( $cluster ); + } + + return $this->extLBs[$cluster]; + } + + public function getAllMainLBs() { + return [ 'DEFAULT' => $this->getMainLB() ]; + } + + public function getAllExternalLBs() { + $lbs = []; + foreach ( $this->externalClusters as $cluster => $unused ) { + $lbs[$cluster] = $this->getExternalLB( $cluster ); + } + + return $lbs; + } + + private function newLoadBalancer( array $servers ) { + $lb = new LoadBalancer( array_merge( + $this->baseLoadBalancerParams(), + [ + 'servers' => $servers, + 'maxLag' => $this->maxLag, + 'loadMonitor' => [ 'class' => $this->loadMonitorClass ], + ] + ) ); + $this->initLoadBalancer( $lb ); + + return $lb; + } + + /** + * Execute a function for each tracked load balancer + * The callback is called with the load balancer as the first parameter, + * and $params passed as the subsequent parameters. + * + * @param callable $callback + * @param array $params + */ + public function forEachLB( $callback, array $params = [] ) { + if ( isset( $this->mainLB ) ) { + call_user_func_array( $callback, array_merge( [ $this->mainLB ], $params ) ); + } + foreach ( $this->extLBs as $lb ) { + call_user_func_array( $callback, array_merge( [ $lb ], $params ) ); + } + } +} |