includes/HTMLFileCache.php

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