includes/HTMLFileCache.php

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