includes/cache/HTMLFileCache.php

   1 <?php
   2 /**
   3  * Contain the HTMLFileCache class
   4  * @file
   5  * @ingroup Cache
   6  */
   7 class HTMLFileCache extends FileCacheBase {
   8         /**
   9          * Construct an ObjectFileCache from a Title and an action
  10          * @param $title Title|string Title object or prefixed DB key string
  11          * @param $action string
  12          * @return HTMLFileCache
  13          */
  14         public static function newFromTitle( $title, $action ) {
  15                 $cache = new self();
  16
  17                 $allowedTypes = self::cacheablePageActions();
  18                 if ( !in_array( $action, $allowedTypes ) ) {
  19                         throw new MWException( "Invalid filecache type given." );
  20                 }
  21                 $cache->mKey = ( $title instanceof Title )
  22                         ? $title->getPrefixedDBkey()
  23                         : (string)$title;
  24                 $cache->mType = (string)$action;
  25                 $cache->mExt = 'html';
  26
  27                 return $cache;
  28         }
  29
  30         /**
  31          * Cacheable actions
  32          * @return array
  33          */
  34         protected static function cacheablePageActions() {
  35                 return array( 'view', 'history' );
  36         }
  37
  38         /**
  39          * Get the base file cache directory
  40          * @return string
  41          */
  42         protected function cacheDirectory() {
  43                 return $this->baseCacheDirectory(); // no subdir for b/c with old cache files
  44         }
  45
  46         /**
  47          * Get the cache type subdirectory (with the trailing slash) or the empty string
  48          * Alter the type -> directory mapping to put action=view cache at the root.
  49          *
  50          * @return string
  51          */
  52         protected function typeSubdirectory() {
  53                 if ( $this->mType === 'view' ) {
  54                         return ''; //  b/c to not skip existing cache
  55                 } else {
  56                         return $this->mType . '/';
  57                 }
  58         }
  59
  60         /**
  61          * Check if pages can be cached for this request/user
  62          * @param $context IContextSource
  63          * @return bool
  64          */
  65         public static function useFileCache( IContextSource $context ) {
  66                 global $wgUseFileCache, $wgShowIPinHeader, $wgDebugToolbar, $wgContLang;
  67                 if ( !$wgUseFileCache ) {
  68                         return false;
  69                 }
  70                 if ( $wgShowIPinHeader || $wgDebugToolbar ) {
  71                         wfDebug( "HTML file cache skipped. Either \$wgShowIPinHeader and/or \$wgDebugToolbar on\n" );
  72                         return false;
  73                 }
  74
  75                 // Get all query values
  76                 $queryVals = $context->getRequest()->getValues();
  77                 foreach ( $queryVals as $query => $val ) {
  78                         if ( $query === 'title' || $query === 'curid' ) {
  79                                 continue; // note: curid sets title
  80                         // Normal page view in query form can have action=view.
  81                         } elseif ( $query === 'action' && in_array( $val, self::cacheablePageActions() ) ) {
  82                                 continue;
  83                         // Below are header setting params
  84                         } elseif ( $query === 'maxage' || $query === 'smaxage' ) {
  85                                 continue;
  86                         }
  87                         return false;
  88                 }
  89                 $user = $context->getUser();
  90                 // Check for non-standard user language; this covers uselang,
  91                 // and extensions for auto-detecting user language.
  92                 $ulang = $context->getLanguage()->getCode();
  93                 $clang = $wgContLang->getCode();
  94                 // Check that there are no other sources of variation
  95                 return !$user->getId() && !$user->getNewtalk() && $ulang == $clang;
  96         }
  97
  98         /**
  99          * Read from cache to context output
 100          * @param $context IContextSource
 101          * @return void
 102          */
 103         public function loadFromFileCache( IContextSource $context ) {
 104                 global $wgMimeType, $wgLanguageCode;
 105
 106                 wfDebug( __METHOD__ . "()\n");
 107                 $filename = $this->cachePath();
 108
 109                 $context->getOutput()->sendCacheControl();
 110                 header( "Content-Type: $wgMimeType; charset=UTF-8" );
 111                 header( "Content-Language: $wgLanguageCode" );
 112                 if ( $this->useGzip() ) {
 113                         if ( wfClientAcceptsGzip() ) {
 114                                 header( 'Content-Encoding: gzip' );
 115                                 readfile( $filename );
 116                         } else {
 117                                 /* Send uncompressed */
 118                                 wfDebug( __METHOD__ . " uncompressing cache file and sending it\n" );
 119                                 readgzfile( $filename );
 120                         }
 121                 }
 122                 $context->getOutput()->disable(); // tell $wgOut that output is taken care of
 123         }
 124
 125         /**
 126          * Save this cache object with the given text.
 127          * Use this as an ob_start() handler.
 128          * @param $text string
 129          * @return bool Whether $wgUseFileCache is enabled
 130          */
 131         public function saveToFileCache( $text ) {
 132                 global $wgUseFileCache;
 133
 134                 if ( !$wgUseFileCache || strlen( $text ) < 512 ) {
 135                         // Disabled or empty/broken output (OOM and PHP errors)
 136                         return $text;
 137                 }
 138
 139                 wfDebug( __METHOD__ . "()\n", false);
 140
 141                 $now = wfTimestampNow();
 142                 if ( $this->useGzip() ) {
 143                         $text = str_replace(
 144                                 '</html>', '<!-- Cached/compressed '.$now." -->\n</html>", $text );
 145                 } else {
 146                         $text = str_replace(
 147                                 '</html>', '<!-- Cached '.$now." -->\n</html>", $text );
 148                 }
 149
 150                 // Store text to FS...
 151                 $compressed = $this->saveText( $text );
 152                 if ( $compressed === false ) {
 153                         return $text; // error
 154                 }
 155
 156                 // gzip output to buffer as needed and set headers...
 157                 if ( $this->useGzip() ) {
 158                         // @TODO: ugly wfClientAcceptsGzip() function - use context!
 159                         if ( wfClientAcceptsGzip() ) {
 160                                 header( 'Content-Encoding: gzip' );
 161                                 return $compressed;
 162                         } else {
 163                                 return $text;
 164                         }
 165                 } else {
 166                         return $text;
 167                 }
 168         }
 169
 170         /**
 171          * Clear the file caches for a page for all actions
 172          * @param $title Title
 173          * @return bool Whether $wgUseFileCache is enabled
 174          */
 175         public static function clearFileCache( Title $title ) {
 176                 global $wgUseFileCache;
 177
 178                 if ( !$wgUseFileCache ) {
 179                         return false;
 180                 }
 181
 182                 foreach ( self::cacheablePageActions() as $type ) {
 183                         $fc = self::newFromTitle( $title, $type );
 184                         $fc->clearCache();
 185                 }
 186
 187                 return true;
 188         }
 189 }