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 /**
  25  * Wrapper around a BagOStuff that caches data in memory
  26  *
  27  * The differences between CachedBagOStuff and MultiWriteBagOStuff are:
  28  * * CachedBagOStuff supports only one "backend".
  29  * * There's a flag for writes to only go to the in-memory cache.
  30  * * The in-memory cache is always updated.
  31  * * Locks go to the backend cache (with MultiWriteBagOStuff, it would wind
  32  *   up going to the HashBagOStuff used for the in-memory cache).
  33  *
  34  * @ingroup Cache
  35  */
  36 class CachedBagOStuff extends BagOStuff {
  37         /** @var BagOStuff */
  38         protected $backend;
  39         /** @var HashBagOStuff */
  40         protected $procCache;
  41
  42         /**
  43          * @param BagOStuff $backend Permanent backend to use
  44          * @param array $params Parameters for HashBagOStuff
  45          */
  46         public function __construct( BagOStuff $backend, $params = [] ) {
  47                 parent::__construct( $params );
  48
  49                 $this->backend = $backend;
  50                 $this->procCache = new HashBagOStuff( $params );
  51                 $this->attrMap = $backend->attrMap;
  52         }
  53
  54         public function setDebug( $enabled ) {
  55                 parent::setDebug( $enabled );
  56                 $this->backend->setDebug( $enabled );
  57         }
  58
  59         public function get( $key, $flags = 0 ) {
  60                 $value = $this->procCache->get( $key, $flags );
  61                 if ( $value === false && !$this->procCache->hasKey( $key ) ) {
  62                         $value = $this->backend->get( $key, $flags );
  63                         $this->set( $key, $value, self::TTL_INDEFINITE, self::WRITE_CACHE_ONLY );
  64                 }
  65
  66                 return $value;
  67         }
  68
  69         public function getMulti( array $keys, $flags = 0 ) {
  70                 $valuesByKeyCached = [];
  71
  72                 $keysMissing = [];
  73                 foreach ( $keys as $key ) {
  74                         $value = $this->procCache->get( $key, $flags );
  75                         if ( $value === false && !$this->procCache->hasKey( $key ) ) {
  76                                 $keysMissing[] = $key;
  77                         } else {
  78                                 $valuesByKeyCached[$key] = $value;
  79                         }
  80                 }
  81
  82                 $valuesByKeyFetched = $this->backend->getMulti( $keys, $flags );
  83                 $this->setMulti( $valuesByKeyFetched, self::TTL_INDEFINITE, self::WRITE_CACHE_ONLY );
  84
  85                 return $valuesByKeyCached + $valuesByKeyFetched;
  86         }
  87
  88         public function set( $key, $value, $exptime = 0, $flags = 0 ) {
  89                 $this->procCache->set( $key, $value, $exptime, $flags );
  90                 if ( ( $flags & self::WRITE_CACHE_ONLY ) != self::WRITE_CACHE_ONLY ) {
  91                         $this->backend->set( $key, $value, $exptime, $flags );
  92                 }
  93
  94                 return true;
  95         }
  96
  97         public function delete( $key, $flags = 0 ) {
  98                 $this->procCache->delete( $key, $flags );
  99                 if ( ( $flags & self::WRITE_CACHE_ONLY ) != self::WRITE_CACHE_ONLY ) {
 100                         $this->backend->delete( $key, $flags );
 101                 }
 102
 103                 return true;
 104         }
 105
 106         public function add( $key, $value, $exptime = 0, $flags = 0 ) {
 107                 if ( $this->get( $key ) === false ) {
 108                         return $this->set( $key, $value, $exptime, $flags );
 109                 }
 110
 111                 return false; // key already set
 112         }
 113
 114         // These just call the backend (tested elsewhere)
 115         // @codeCoverageIgnoreStart
 116
 117         public function merge( $key, callable $callback, $exptime = 0, $attempts = 10, $flags = 0 ) {
 118                 $this->procCache->delete( $key );
 119
 120                 return $this->backend->merge( $key, $callback, $exptime, $attempts, $flags );
 121         }
 122
 123         public function changeTTL( $key, $exptime = 0, $flags = 0 ) {
 124                 $this->procCache->delete( $key );
 125
 126                 return $this->backend->changeTTL( $key, $exptime, $flags );
 127         }
 128
 129         public function lock( $key, $timeout = 6, $expiry = 6, $rclass = '' ) {
 130                 return $this->backend->lock( $key, $timeout, $expiry, $rclass );
 131         }
 132
 133         public function unlock( $key ) {
 134                 return $this->backend->unlock( $key );
 135         }
 136
 137         public function deleteObjectsExpiringBefore(
 138                 $timestamp,
 139                 callable $progress = null,
 140                 $limit = INF
 141         ) {
 142                 $this->procCache->deleteObjectsExpiringBefore( $timestamp, $progress, $limit );
 143
 144                 return $this->backend->deleteObjectsExpiringBefore( $timestamp, $progress, $limit );
 145         }
 146
 147         public function makeKeyInternal( $keyspace, $args ) {
 148                 return $this->backend->makeKeyInternal( $keyspace, $args );
 149         }
 150
 151         public function makeKey( $class, ...$components ) {
 152                 return $this->backend->makeKey( $class, ...$components );
 153         }
 154
 155         public function makeGlobalKey( $class, ...$components ) {
 156                 return $this->backend->makeGlobalKey( $class, ...$components );
 157         }
 158
 159         public function getLastError() {
 160                 return $this->backend->getLastError();
 161         }
 162
 163         public function clearLastError() {
 164                 return $this->backend->clearLastError();
 165         }
 166
 167         public function setMulti( array $data, $exptime = 0, $flags = 0 ) {
 168                 $this->procCache->setMulti( $data, $exptime, $flags );
 169                 if ( ( $flags & self::WRITE_CACHE_ONLY ) != self::WRITE_CACHE_ONLY ) {
 170                         return $this->backend->setMulti( $data, $exptime, $flags );
 171                 }
 172
 173                 return true;
 174         }
 175
 176         public function deleteMulti( array $keys, $flags = 0 ) {
 177                 $this->procCache->deleteMulti( $keys, $flags );
 178                 if ( ( $flags & self::WRITE_CACHE_ONLY ) != self::WRITE_CACHE_ONLY ) {
 179                         return $this->backend->deleteMulti( $keys, $flags );
 180                 }
 181
 182                 return true;
 183         }
 184
 185         public function changeTTLMulti( array $keys, $exptime, $flags = 0 ) {
 186                 $this->procCache->changeTTLMulti( $keys, $exptime, $flags );
 187                 if ( ( $flags & self::WRITE_CACHE_ONLY ) != self::WRITE_CACHE_ONLY ) {
 188                         return $this->backend->changeTTLMulti( $keys, $exptime, $flags );
 189                 }
 190
 191                 return true;
 192         }
 193
 194         public function incr( $key, $value = 1 ) {
 195                 $this->procCache->delete( $key );
 196
 197                 return $this->backend->incr( $key, $value );
 198         }
 199
 200         public function decr( $key, $value = 1 ) {
 201                 $this->procCache->delete( $key );
 202
 203                 return $this->backend->decr( $key, $value );
 204         }
 205
 206         public function incrWithInit( $key, $ttl, $value = 1, $init = 1 ) {
 207                 $this->procCache->delete( $key );
 208
 209                 return $this->backend->incrWithInit( $key, $ttl, $value, $init );
 210         }
 211
 212         public function addBusyCallback( callable $workCallback ) {
 213                 $this->backend->addBusyCallback( $workCallback );
 214         }
 215
 216         public function setMockTime( &$time ) {
 217                 parent::setMockTime( $time );
 218                 $this->procCache->setMockTime( $time );
 219                 $this->backend->setMockTime( $time );
 220         }
 221
 222         // @codeCoverageIgnoreEnd
 223 }