includes/cache/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 for the emergency abort/fallback to cache.
  11  *
  12  * Global options that affect this module:
  13  * - $wgCachePages
  14  * - $wgCacheEpoch
  15  * - $wgUseFileCache
  16  * - $wgCacheDirectory
  17  * - $wgFileCacheDirectory
  18  * - $wgUseGzip
  19  *
  20  * @ingroup Cache
  21  */
  22 class HTMLFileCache {
  23
  24         /**
  25          * @var Title
  26          */
  27         var $mTitle;
  28         var $mFileCache, $mType;
  29
  30         public function __construct( $title, $type = 'view' ) {
  31                 $this->mTitle = $title;
  32                 $this->mType = ($type == 'raw' || $type == 'view' ) ? $type : false;
  33                 $this->fileCacheName(); // init name
  34         }
  35
  36         public function fileCacheName() {
  37                 if( !$this->mFileCache ) {
  38                         global $wgCacheDirectory, $wgFileCacheDirectory, $wgFileCacheDepth;
  39
  40                         if ( $wgFileCacheDirectory ) {
  41                                 $dir = $wgFileCacheDirectory;
  42                         } elseif ( $wgCacheDirectory ) {
  43                                 $dir = "$wgCacheDirectory/html";
  44                         } else {
  45                                 throw new MWException( 'Please set $wgCacheDirectory in LocalSettings.php if you wish to use the HTML file cache' );
  46                         }
  47
  48                         # Store raw pages (like CSS hits) elsewhere
  49                         $subdir = ($this->mType === 'raw') ? 'raw/' : '';
  50
  51                         $key = $this->mTitle->getPrefixedDbkey();
  52                         if ( $wgFileCacheDepth > 0 ) {
  53                                 $hash = md5( $key );
  54                                 for ( $i = 1; $i <= $wgFileCacheDepth; $i++ ) {
  55                                         $subdir .= substr( $hash, 0, $i ) . '/';
  56                                 }
  57                         }
  58                         # Avoid extension confusion
  59                         $key = str_replace( '.', '%2E', urlencode( $key ) );
  60                         $this->mFileCache = "{$dir}/{$subdir}{$key}.html";
  61
  62                         if( $this->useGzip() ) {
  63                                 $this->mFileCache .= '.gz';
  64                         }
  65
  66                         wfDebug( __METHOD__ . ": {$this->mFileCache}\n" );
  67                 }
  68                 return $this->mFileCache;
  69         }
  70
  71         public function isFileCached() {
  72                 if( $this->mType === false ) {
  73                         return false;
  74                 }
  75                 return file_exists( $this->fileCacheName() );
  76         }
  77
  78         public function fileCacheTime() {
  79                 return wfTimestamp( TS_MW, filemtime( $this->fileCacheName() ) );
  80         }
  81
  82         /**
  83          * Check if pages can be cached for this request/user
  84          * @return bool
  85          */
  86         public static function useFileCache() {
  87                 global $wgUser, $wgUseFileCache, $wgShowIPinHeader, $wgRequest, $wgLang, $wgContLang;
  88                 if( !$wgUseFileCache ) {
  89                         return false;
  90                 }
  91                 // Get all query values
  92                 $queryVals = $wgRequest->getValues();
  93                 foreach( $queryVals as $query => $val ) {
  94                         if( $query == 'title' || $query == 'curid' ) {
  95                                 continue;
  96                         // Normal page view in query form can have action=view.
  97                         // Raw hits for pages also stored, like .css pages for example.
  98                         } elseif( $query == 'action' && $val == 'view' ) {
  99                                 continue;
 100                         } elseif( $query == 'usemsgcache' && $val == 'yes' ) {
 101                                 continue;
 102                         // Below are header setting params
 103                         } elseif( $query == 'maxage' || $query == 'smaxage' || $query == 'ctype' || $query == 'gen' ) {
 104                                 continue;
 105                         } else {
 106                                 return false;
 107                         }
 108                 }
 109                 // Check for non-standard user language; this covers uselang,
 110                 // and extensions for auto-detecting user language.
 111                 $ulang = $wgLang->getCode();
 112                 $clang = $wgContLang->getCode();
 113                 // Check that there are no other sources of variation
 114                 return !$wgShowIPinHeader && !$wgUser->getId() && !$wgUser->getNewtalk() && $ulang == $clang;
 115         }
 116
 117         /**
 118          * Check if up to date cache file exists
 119          * @param $timestamp string
 120          *
 121          * @return bool
 122          */
 123         public function isFileCacheGood( $timestamp = '' ) {
 124                 global $wgCacheEpoch;
 125
 126                 if( !$this->isFileCached() ) {
 127                         return false;
 128                 }
 129
 130                 $cachetime = $this->fileCacheTime();
 131                 $good = $timestamp <= $cachetime && $wgCacheEpoch <= $cachetime;
 132
 133                 wfDebug( __METHOD__ . ": cachetime $cachetime, touched '{$timestamp}' epoch {$wgCacheEpoch}, good $good\n");
 134                 return $good;
 135         }
 136
 137         public function useGzip() {
 138                 global $wgUseGzip;
 139                 return $wgUseGzip;
 140         }
 141
 142         /* In handy string packages */
 143         public function fetchRawText() {
 144                 return file_get_contents( $this->fileCacheName() );
 145         }
 146
 147         public function fetchPageText() {
 148                 if( $this->useGzip() ) {
 149                         /* Why is there no gzfile_get_contents() or gzdecode()? */
 150                         return implode( '', gzfile( $this->fileCacheName() ) );
 151                 } else {
 152                         return $this->fetchRawText();
 153                 }
 154         }
 155
 156         /* Working directory to/from output */
 157         public function loadFromFileCache() {
 158                 global $wgOut, $wgMimeType, $wgLanguageCode;
 159                 wfDebug( __METHOD__ . "()\n");
 160                 $filename = $this->fileCacheName();
 161                 // Raw pages should handle cache control on their own,
 162                 // even when using file cache. This reduces hits from clients.
 163                 if( $this->mType !== 'raw' ) {
 164                         $wgOut->sendCacheControl();
 165                         header( "Content-Type: $wgMimeType; charset=UTF-8" );
 166                         header( "Content-Language: $wgLanguageCode" );
 167                 }
 168
 169                 if( $this->useGzip() ) {
 170                         if( wfClientAcceptsGzip() ) {
 171                                 header( 'Content-Encoding: gzip' );
 172                         } else {
 173                                 /* Send uncompressed */
 174                                 readgzfile( $filename );
 175                                 return;
 176                         }
 177                 }
 178                 readfile( $filename );
 179                 $wgOut->disable(); // tell $wgOut that output is taken care of
 180         }
 181
 182         protected function checkCacheDirs() {
 183                 $filename = $this->fileCacheName();
 184                 $mydir2 = substr($filename,0,strrpos($filename,'/')); # subdirectory level 2
 185                 $mydir1 = substr($mydir2,0,strrpos($mydir2,'/')); # subdirectory level 1
 186
 187                 wfMkdirParents( $mydir1 );
 188                 wfMkdirParents( $mydir2 );
 189         }
 190
 191         public function saveToFileCache( $text ) {
 192                 global $wgUseFileCache;
 193                 if( !$wgUseFileCache || strlen( $text ) < 512 ) {
 194                         // Disabled or empty/broken output (OOM and PHP errors)
 195                         return $text;
 196                 }
 197
 198                 wfDebug( __METHOD__ . "()\n", false);
 199
 200                 $this->checkCacheDirs();
 201
 202                 $f = fopen( $this->fileCacheName(), 'w' );
 203                 if($f) {
 204                         $now = wfTimestampNow();
 205                         if( $this->useGzip() ) {
 206                                 $rawtext = str_replace( '</html>',
 207                                         '<!-- Cached/compressed '.$now." -->\n</html>",
 208                                         $text );
 209                                 $text = gzencode( $rawtext );
 210                         } else {
 211                                 $text = str_replace( '</html>',
 212                                         '<!-- Cached '.$now." -->\n</html>",
 213                                         $text );
 214                         }
 215                         fwrite( $f, $text );
 216                         fclose( $f );
 217                         if( $this->useGzip() ) {
 218                                 if( wfClientAcceptsGzip() ) {
 219                                         header( 'Content-Encoding: gzip' );
 220                                         return $text;
 221                                 } else {
 222                                         return $rawtext;
 223                                 }
 224                         } else {
 225                                 return $text;
 226                         }
 227                 }
 228                 return $text;
 229         }
 230
 231         public static function clearFileCache( $title ) {
 232                 global $wgUseFileCache;
 233
 234                 if ( !$wgUseFileCache ) {
 235                         return false;
 236                 }
 237
 238                 wfSuppressWarnings();
 239
 240                 $fc = new self( $title, 'view' );
 241                 unlink( $fc->fileCacheName() );
 242
 243                 $fc = new self( $title, 'raw' );
 244                 unlink( $fc->fileCacheName() );
 245
 246                 wfRestoreWarnings();
 247
 248                 return true;
 249         }
 250 }