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\ILoadBalancer;
  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 array */
  38         protected $fileFactory = [ ForeignDBFile::class, 'newFromTitle' ];
  39
  40         /** @var array */
  41         protected $fileFromRowFactory = [ ForeignDBFile::class, 'newFromRow' ];
  42
  43         /** @var bool */
  44         protected $hasSharedCache;
  45
  46         /**
  47          * @param array|null $info
  48          */
  49         function __construct( $info ) {
  50                 parent::__construct( $info );
  51                 $this->wiki = $info['wiki'];
  52                 $this->hasSharedCache = $info['hasSharedCache'];
  53         }
  54
  55         /**
  56          * @return IDatabase
  57          */
  58         function getMasterDB() {
  59                 return $this->getDBLoadBalancer()->getConnectionRef( DB_MASTER, [], $this->wiki );
  60         }
  61
  62         /**
  63          * @return IDatabase
  64          */
  65         function getReplicaDB() {
  66                 return $this->getDBLoadBalancer()->getConnectionRef( DB_REPLICA, [], $this->wiki );
  67         }
  68
  69         /**
  70          * @return Closure
  71          */
  72         protected function getDBFactory() {
  73                 return function ( $index ) {
  74                         return $this->getDBLoadBalancer()->getConnectionRef( $index, [], $this->wiki );
  75                 };
  76         }
  77
  78         /**
  79          * @return ILoadBalancer
  80          */
  81         protected function getDBLoadBalancer() {
  82                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
  83
  84                 return $lbFactory->getMainLB( $this->wiki );
  85         }
  86
  87         function hasSharedCache() {
  88                 return $this->hasSharedCache;
  89         }
  90
  91         /**
  92          * Get a key on the primary cache for this repository.
  93          * Returns false if the repository's cache is not accessible at this site.
  94          * The parameters are the parts of the key, as for wfMemcKey().
  95          * @return bool|string
  96          */
  97         function getSharedCacheKey( /*...*/ ) {
  98                 if ( $this->hasSharedCache() ) {
  99                         $args = func_get_args();
 100                         array_unshift( $args, $this->wiki );
 101
 102                         return implode( ':', $args );
 103                 } else {
 104                         return false;
 105                 }
 106         }
 107
 108         protected function assertWritableRepo() {
 109                 throw new MWException( static::class . ': write operations are not supported.' );
 110         }
 111
 112         public function getInfo() {
 113                 return FileRepo::getInfo();
 114         }
 115 }