includes/site/SiteListFileCache.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  *
  20  * @license GNU GPL v2+
  21  */
  22
  23 /**
  24  * Provides a file-based cache of a SiteStore, stored as a json file.
  25  * The cache can be built with the rebuildSitesCache.php maintenance script,
  26  * and a MediaWiki instance can be setup to use this by setting the
  27  * 'wgSitesCacheFile' configuration to the cache file location.
  28  *
  29  * @since 1.25
  30  */
  31 class SiteListFileCache {
  32
  33         /**
  34          * @var SiteList
  35          */
  36         private $sites = null;
  37
  38         /**
  39          * @var string
  40          */
  41         private $cacheFile;
  42
  43         /**
  44          * @param string $cacheFile
  45          */
  46         public function __construct( $cacheFile ) {
  47                 $this->cacheFile = $cacheFile;
  48         }
  49
  50         /**
  51          * @since 1.25
  52          *
  53          * @return SiteList
  54          */
  55         public function getSites() {
  56                 if ( $this->sites === null ) {
  57                         $this->sites = $this->loadSitesFromCache();
  58                 }
  59
  60                 return $this->sites;
  61         }
  62
  63         /**
  64          * @param string $globalId
  65          *
  66          * @since 1.25
  67          *
  68          * @return Site|null
  69          */
  70         public function getSite( $globalId ) {
  71                 $sites = $this->getSites();
  72
  73                 return $sites->hasSite( $globalId ) ? $sites->getSite( $globalId ) : null;
  74         }
  75
  76         /**
  77          * @return SiteList
  78          */
  79         private function loadSitesFromCache() {
  80                 $data = $this->loadJsonFile();
  81
  82                 $sites = new SiteList();
  83
  84                 // @todo lazy initialize the site objects in the site list (e.g. only when needed to access)
  85                 foreach ( $data['sites'] as $siteArray ) {
  86                         $sites[] = $this->newSiteFromArray( $siteArray );
  87                 }
  88
  89                 return $sites;
  90         }
  91
  92         /**
  93          * @throws MWException
  94          * @return array
  95          */
  96         private function loadJsonFile() {
  97                 if ( !is_readable( $this->cacheFile ) ) {
  98                         throw new MWException( 'SiteList cache file not found.' );
  99                 }
 100
 101                 $contents = file_get_contents( $this->cacheFile );
 102                 $data = json_decode( $contents, true );
 103
 104                 if ( !is_array( $data ) || !array_key_exists( 'sites', $data ) ) {
 105                         throw new MWException( 'SiteStore json cache data is invalid.' );
 106                 }
 107
 108                 return $data;
 109         }
 110
 111         /**
 112          * @param array $data
 113          *
 114          * @return Site
 115          */
 116         private function newSiteFromArray( array $data ) {
 117                 $siteType = array_key_exists( 'type', $data ) ? $data['type'] : Site::TYPE_UNKNOWN;
 118                 $site = Site::newForType( $siteType );
 119
 120                 $site->setGlobalId( $data['globalid'] );
 121                 $site->setInternalId( $data['internalid'] );
 122                 $site->setForward( $data['forward'] );
 123                 $site->setGroup( $data['group'] );
 124                 $site->setLanguageCode( $data['language'] );
 125                 $site->setSource( $data['source'] );
 126                 $site->setExtraData( $data['data'] );
 127                 $site->setExtraConfig( $data['config'] );
 128
 129                 foreach ( $data['identifiers'] as $identifier ) {
 130                         $site->addLocalId( $identifier['type'], $identifier['key'] );
 131                 }
 132
 133                 return $site;
 134         }
 135
 136 }