includes/CacheManager.php

   1 <?php
   2 /**
   3  * Contain the CacheManager class
   4  */
   5
   6 /**
   7  * We need the title class
   8  */
   9 require_once( 'Title.php' );
  10
  11 /**
  12  * Handles talking to the file cache, putting stuff in and taking it back out.
  13  * Mostly called from Article.php, also from DatabaseFunctions.php for the
  14  * emergency abort/fallback to cache.
  15  *
  16  * Global options that affect this module:
  17  * $wgCachePages
  18  * $wgCacheEpoch
  19  * $wgUseFileCache
  20  * $wgFileCacheDirectory
  21  * $wgUseGzip
  22  */
  23 class CacheManager {
  24         var $mTitle, $mFileCache;
  25
  26         function CacheManager( &$title ) {
  27                 $this->mTitle =& $title;
  28                 $this->mFileCache = '';
  29         }
  30
  31         function fileCacheName() {
  32                 global $wgFileCacheDirectory, $wgLang;
  33                 if( !$this->mFileCache ) {
  34                         $hash = md5( $key = $this->mTitle->getDbkey() );
  35                         if( $this->mTitle->getNamespace() )
  36                                 $key = $wgLang->getNsText( $this->mTitle->getNamespace() ) . ":" . $key;
  37                         $key = str_replace( '.', '%2E', urlencode( $key ) );
  38
  39                         $hash1 = substr( $hash, 0, 1 );
  40                         $hash2 = substr( $hash, 0, 2 );
  41                         $this->mFileCache = "{$wgFileCacheDirectory}/{$hash1}/{$hash2}/{$key}.html";
  42
  43                         if($this->useGzip())
  44                                 $this->mFileCache .= '.gz';
  45
  46                         wfDebug( " fileCacheName() - {$this->mFileCache}\n" );
  47                 }
  48                 return $this->mFileCache;
  49         }
  50
  51         function isFileCached() {
  52                 return file_exists( $this->fileCacheName() );
  53         }
  54
  55         function fileCacheTime() {
  56                 return wfUnix2Timestamp( filemtime( $this->fileCacheName() ) );
  57         }
  58
  59         function isFileCacheGood( $timestamp ) {
  60                 global $wgCacheEpoch;
  61
  62                 if( !$this->isFileCached() ) return false;
  63
  64                 $cachetime = $this->fileCacheTime();
  65                 $good = (( $timestamp <= $cachetime ) &&
  66                          ( $wgCacheEpoch <= $cachetime ));
  67
  68                 wfDebug(" isFileCacheGood() - cachetime $cachetime, touched {$timestamp} epoch {$wgCacheEpoch}, good $good\n");
  69                 return $good;
  70         }
  71
  72         function useGzip() {
  73                 global $wgUseGzip;
  74                 return $wgUseGzip;
  75         }
  76
  77         /* In handy string packages */
  78         function fetchRawText() {
  79                 return file_get_contents( $this->fileCacheName() );
  80         }
  81
  82         function fetchPageText() {
  83                 if( $this->useGzip() ) {
  84                         /* Why is there no gzfile_get_contents() or gzdecode()? */
  85                         return implode( '', gzfile( $this->fileCacheName() ) );
  86                 } else {
  87                         return $this->fetchRawText();
  88                 }
  89         }
  90
  91         /* Working directory to/from output */
  92         function loadFromFileCache() {
  93                 global $wgOut;
  94                 wfDebug(" loadFromFileCache()\n");
  95
  96                 $filename=$this->fileCacheName();
  97                 $wgOut->sendCacheControl();
  98
  99                 if( $this->useGzip() ) {
 100                         if( wfClientAcceptsGzip() ) {
 101                                 header( 'Content-Encoding: gzip' );
 102                         } else {
 103                                 /* Send uncompressed */
 104                                 readgzfile( $filename );
 105                                 return;
 106                         }
 107                 }
 108                 readfile( $filename );
 109         }
 110
 111         function checkCacheDirs() {
 112                 $filename = $this->fileCacheName();
 113                 $mydir2=substr($filename,0,strrpos($filename,'/')); # subdirectory level 2
 114                 $mydir1=substr($mydir2,0,strrpos($mydir2,'/')); # subdirectory level 1
 115
 116                 if(!file_exists($mydir1)) { mkdir($mydir1,0775); } # create if necessary
 117                 if(!file_exists($mydir2)) { mkdir($mydir2,0775); }
 118         }
 119
 120         function saveToFileCache( $origtext ) {
 121                 $text = $origtext;
 122                 if(strcmp($text,'') == 0) return '';
 123
 124                 wfDebug(" saveToFileCache()\n", false);
 125
 126                 $this->checkCacheDirs();
 127
 128                 $f = fopen( $this->fileCacheName(), 'w' );
 129                 if($f) {
 130                         $now = wfTimestampNow();
 131                         if( $this->useGzip() ) {
 132                                 $rawtext = str_replace( '</html>',
 133                                         '<!-- Cached/compressed '.$now." -->\n</html>",
 134                                         $text );
 135                                 $text = gzencode( $rawtext );
 136                         } else {
 137                                 $text = str_replace( '</html>',
 138                                         '<!-- Cached '.$now." -->\n</html>",
 139                                         $text );
 140                         }
 141                         fwrite( $f, $text );
 142                         fclose( $f );
 143                         if( $this->useGzip() ) {
 144                                 if( wfClientAcceptsGzip() ) {
 145                                         header( 'Content-Encoding: gzip' );
 146                                         return $text;
 147                                 } else {
 148                                         return $rawtext;
 149                                 }
 150                         } else {
 151                                 return $text;
 152                         }
 153                 }
 154                 return $text;
 155         }
 156
 157 }
 158
 159 ?>