includes/CacheManager.php

   1 <?php
   2 /**
   3  * Contain the CacheManager class
   4  * @package MediaWiki
   5  * @subpackage Cache
   6  */
   7
   8 /**
   9  * We need the title class
  10  */
  11 require_once( 'Title.php' );
  12
  13 /**
  14  * Handles talking to the file cache, putting stuff in and taking it back out.
  15  * Mostly called from Article.php, also from DatabaseFunctions.php for the
  16  * emergency abort/fallback to cache.
  17  *
  18  * Global options that affect this module:
  19  * $wgCachePages
  20  * $wgCacheEpoch
  21  * $wgUseFileCache
  22  * $wgFileCacheDirectory
  23  * $wgUseGzip
  24  * @package MediaWiki
  25  */
  26 class CacheManager {
  27         var $mTitle, $mFileCache;
  28
  29         function CacheManager( &$title ) {
  30                 $this->mTitle =& $title;
  31                 $this->mFileCache = '';
  32         }
  33
  34         function fileCacheName() {
  35                 global $wgFileCacheDirectory, $wgContLang;
  36                 if( !$this->mFileCache ) {
  37                         $hash = md5( $key = $this->mTitle->getDbkey() );
  38                         if( $this->mTitle->getNamespace() )
  39                                 $key = $wgContLang->getNsText( $this->mTitle->getNamespace() ) . ":" . $key;
  40                         $key = str_replace( '.', '%2E', urlencode( $key ) );
  41
  42                         $hash1 = substr( $hash, 0, 1 );
  43                         $hash2 = substr( $hash, 0, 2 );
  44                         $this->mFileCache = "{$wgFileCacheDirectory}/{$hash1}/{$hash2}/{$key}.html";
  45
  46                         if($this->useGzip())
  47                                 $this->mFileCache .= '.gz';
  48
  49                         wfDebug( " fileCacheName() - {$this->mFileCache}\n" );
  50                 }
  51                 return $this->mFileCache;
  52         }
  53
  54         function isFileCached() {
  55                 return file_exists( $this->fileCacheName() );
  56         }
  57
  58         function fileCacheTime() {
  59                 return wfTimestamp( TS_MW, filemtime( $this->fileCacheName() ) );
  60         }
  61
  62         function isFileCacheGood( $timestamp ) {
  63                 global $wgCacheEpoch;
  64
  65                 if( !$this->isFileCached() ) return false;
  66
  67                 $cachetime = $this->fileCacheTime();
  68                 $good = (( $timestamp <= $cachetime ) &&
  69                          ( $wgCacheEpoch <= $cachetime ));
  70
  71                 wfDebug(" isFileCacheGood() - cachetime $cachetime, touched {$timestamp} epoch {$wgCacheEpoch}, good $good\n");
  72                 return $good;
  73         }
  74
  75         function useGzip() {
  76                 global $wgUseGzip;
  77                 return $wgUseGzip;
  78         }
  79
  80         /* In handy string packages */
  81         function fetchRawText() {
  82                 return file_get_contents( $this->fileCacheName() );
  83         }
  84
  85         function fetchPageText() {
  86                 if( $this->useGzip() ) {
  87                         /* Why is there no gzfile_get_contents() or gzdecode()? */
  88                         return implode( '', gzfile( $this->fileCacheName() ) );
  89                 } else {
  90                         return $this->fetchRawText();
  91                 }
  92         }
  93
  94         /* Working directory to/from output */
  95         function loadFromFileCache() {
  96                 global $wgOut, $wgMimeType, $wgOutputEncoding, $wgContLanguageCode;
  97                 wfDebug(" loadFromFileCache()\n");
  98
  99                 $filename=$this->fileCacheName();
 100                 $wgOut->sendCacheControl();
 101
 102                 header( "Content-type: $wgMimeType; charset={$wgOutputEncoding}" );
 103                 header( "Content-language: $wgContLanguageCode" );
 104
 105                 if( $this->useGzip() ) {
 106                         if( wfClientAcceptsGzip() ) {
 107                                 header( 'Content-Encoding: gzip' );
 108                         } else {
 109                                 /* Send uncompressed */
 110                                 readgzfile( $filename );
 111                                 return;
 112                         }
 113                 }
 114                 readfile( $filename );
 115         }
 116
 117         function checkCacheDirs() {
 118                 $filename = $this->fileCacheName();
 119                 $mydir2=substr($filename,0,strrpos($filename,'/')); # subdirectory level 2
 120                 $mydir1=substr($mydir2,0,strrpos($mydir2,'/')); # subdirectory level 1
 121
 122                 if(!file_exists($mydir1)) { mkdir($mydir1,0775); } # create if necessary
 123                 if(!file_exists($mydir2)) { mkdir($mydir2,0775); }
 124         }
 125
 126         function saveToFileCache( $origtext ) {
 127                 $text = $origtext;
 128                 if(strcmp($text,'') == 0) return '';
 129
 130                 wfDebug(" saveToFileCache()\n", false);
 131
 132                 $this->checkCacheDirs();
 133
 134                 $f = fopen( $this->fileCacheName(), 'w' );
 135                 if($f) {
 136                         $now = wfTimestampNow();
 137                         if( $this->useGzip() ) {
 138                                 $rawtext = str_replace( '</html>',
 139                                         '<!-- Cached/compressed '.$now." -->\n</html>",
 140                                         $text );
 141                                 $text = gzencode( $rawtext );
 142                         } else {
 143                                 $text = str_replace( '</html>',
 144                                         '<!-- Cached '.$now." -->\n</html>",
 145                                         $text );
 146                         }
 147                         fwrite( $f, $text );
 148                         fclose( $f );
 149                         if( $this->useGzip() ) {
 150                                 if( wfClientAcceptsGzip() ) {
 151                                         header( 'Content-Encoding: gzip' );
 152                                         return $text;
 153                                 } else {
 154                                         return $rawtext;
 155                                 }
 156                         } else {
 157                                 return $text;
 158                         }
 159                 }
 160                 return $text;
 161         }
 162
 163 }
 164
 165 ?>