includes/filerepo/ForeignDBViaLBRepo.php

   1 <?php
   2 /**
   3  * A foreign repository with a MediaWiki database accessible via the configured LBFactory.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup FileRepo
  22  */
  23
  24 use MediaWiki\MediaWikiServices;
  25 use Wikimedia\Rdbms\IDatabase;
  26 use Wikimedia\Rdbms\LoadBalancer;
  27
  28 /**
  29  * A foreign repository with a MediaWiki database accessible via the configured LBFactory
  30  *
  31  * @ingroup FileRepo
  32  */
  33 class ForeignDBViaLBRepo extends LocalRepo {
  34         /** @var string */
  35         protected $wiki;
  36
  37         /** @var string */
  38         protected $dbName;
  39
  40         /** @var string */
  41         protected $tablePrefix;
  42
  43         /** @var array */
  44         protected $fileFactory = [ ForeignDBFile::class, 'newFromTitle' ];
  45
  46         /** @var array */
  47         protected $fileFromRowFactory = [ ForeignDBFile::class, 'newFromRow' ];
  48
  49         /** @var bool */
  50         protected $hasSharedCache;
  51
  52         /**
  53          * @param array|null $info
  54          */
  55         function __construct( $info ) {
  56                 parent::__construct( $info );
  57                 $this->wiki = $info['wiki'];
  58                 list( $this->dbName, $this->tablePrefix ) = wfSplitWikiID( $this->wiki );
  59                 $this->hasSharedCache = $info['hasSharedCache'];
  60         }
  61
  62         /**
  63          * @return IDatabase
  64          */
  65         function getMasterDB() {
  66                 return $this->getDBLoadBalancer()->getConnectionRef( DB_MASTER, [], $this->wiki );
  67         }
  68
  69         /**
  70          * @return IDatabase
  71          */
  72         function getReplicaDB() {
  73                 return $this->getDBLoadBalancer()->getConnectionRef( DB_REPLICA, [], $this->wiki );
  74         }
  75
  76         /**
  77          * @return Closure
  78          */
  79         protected function getDBFactory() {
  80                 return function ( $index ) {
  81                         return $this->getDBLoadBalancer()->getConnectionRef( $index, [], $this->wiki );
  82                 };
  83         }
  84
  85         /**
  86          * @return LoadBalancer
  87          */
  88         protected function getDBLoadBalancer() {
  89                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
  90                 return $lbFactory->getMainLB( $this->wiki );
  91         }
  92
  93         function hasSharedCache() {
  94                 return $this->hasSharedCache;
  95         }
  96
  97         /**
  98          * Get a key on the primary cache for this repository.
  99          * Returns false if the repository's cache is not accessible at this site.
 100          * The parameters are the parts of the key, as for wfMemcKey().
 101          * @return bool|string
 102          */
 103         function getSharedCacheKey( /*...*/ ) {
 104                 if ( $this->hasSharedCache() ) {
 105                         $args = func_get_args();
 106                         array_unshift( $args, $this->wiki );
 107
 108                         return implode( ':', $args );
 109                 } else {
 110                         return false;
 111                 }
 112         }
 113
 114         protected function assertWritableRepo() {
 115                 throw new MWException( static::class . ': write operations are not supported.' );
 116         }
 117
 118         public function getInfo() {
 119                 return FileRepo::getInfo();
 120         }
 121 }