includes/libs/objectcache/CachedBagOStuff.php

   1 <?php
   2 /**
   3  * Wrapper around a BagOStuff that caches data in memory
   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 Cache
  22  */
  23
  24 use Psr\Log\LoggerInterface;
  25
  26 /**
  27  * Wrapper around a BagOStuff that caches data in memory
  28  *
  29  * The differences between CachedBagOStuff and MultiWriteBagOStuff are:
  30  * * CachedBagOStuff supports only one "backend".
  31  * * There's a flag for writes to only go to the in-memory cache.
  32  * * The in-memory cache is always updated.
  33  * * Locks go to the backend cache (with MultiWriteBagOStuff, it would wind
  34  *   up going to the HashBagOStuff used for the in-memory cache).
  35  *
  36  * @ingroup Cache
  37  */
  38 class CachedBagOStuff extends HashBagOStuff {
  39         /** @var BagOStuff */
  40         protected $backend;
  41
  42         /**
  43          * @param BagOStuff $backend Permanent backend to use
  44          * @param array $params Parameters for HashBagOStuff
  45          */
  46         function __construct( BagOStuff $backend, $params = array() ) {
  47                 $this->backend = $backend;
  48                 parent::__construct( $params );
  49         }
  50
  51         protected function doGet( $key, $flags = 0 ) {
  52                 $ret = parent::doGet( $key, $flags );
  53                 if ( $ret === false ) {
  54                         $ret = $this->backend->doGet( $key, $flags );
  55                         if ( $ret !== false ) {
  56                                 $this->set( $key, $ret, 0, self::WRITE_CACHE_ONLY );
  57                         }
  58                 }
  59                 return $ret;
  60         }
  61
  62         public function set( $key, $value, $exptime = 0, $flags = 0 ) {
  63                 parent::set( $key, $value, $exptime, $flags );
  64                 if ( !( $flags & self::WRITE_CACHE_ONLY ) ) {
  65                         $this->backend->set( $key, $value, $exptime, $flags & ~self::WRITE_CACHE_ONLY );
  66                 }
  67                 return true;
  68         }
  69
  70         public function delete( $key, $flags = 0 ) {
  71                 unset( $this->bag[$key] );
  72                 if ( !( $flags & self::WRITE_CACHE_ONLY ) ) {
  73                         $this->backend->delete( $key );
  74                 }
  75
  76                 return true;
  77         }
  78
  79         public function setLogger( LoggerInterface $logger ) {
  80                 parent::setLogger( $logger );
  81                 $this->backend->setLogger( $logger );
  82         }
  83
  84         public function setDebug( $bool ) {
  85                 parent::setDebug( $bool );
  86                 $this->backend->setDebug( $bool );
  87         }
  88
  89         public function lock( $key, $timeout = 6, $expiry = 6, $rclass = '' ) {
  90                 return $this->backend->lock( $key, $timeout, $expiry, $rclass );
  91         }
  92
  93         public function unlock( $key ) {
  94                 return $this->backend->unlock( $key );
  95         }
  96
  97         public function deleteObjectsExpiringBefore( $date, $progressCallback = false ) {
  98                 parent::deleteObjectsExpiringBefore( $date, $progressCallback );
  99                 return $this->backend->deleteObjectsExpiringBefore( $date, $progressCallback );
 100         }
 101
 102         public function getLastError() {
 103                 return $this->backend->getLastError();
 104         }
 105
 106         public function clearLastError() {
 107                 $this->backend->clearLastError();
 108         }
 109
 110         public function modifySimpleRelayEvent( array $event ) {
 111                 return $this->backend->modifySimpleRelayEvent( $event );
 112         }
 113
 114 }