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          * @return string
  49          */
  50         protected function typeSubdirectory() {
  51                 if ( $this->mType === 'view' ) {
  52                         return ''; //  b/c to not skip existing cache
  53                 } else {
  54                         return $this->mType . '/';
  55                 }
  56         }
  57
  58         /**
  59          * Check if pages can be cached for this request/user
  60          * @param $context IContextSource
  61          * @return bool
  62          */
  63         public static function useFileCache( IContextSource $context ) {
  64                 global $wgUseFileCache, $wgShowIPinHeader, $wgDebugToolbar, $wgContLang;
  65                 if ( !$wgUseFileCache ) {
  66                         return false;
  67                 }
  68                 if ( $wgShowIPinHeader || $wgDebugToolbar ) {
  69                         wfDebug( "HTML file cache skipped. Either \$wgShowIPinHeader and/or \$wgDebugToolbar on\n" );
  70                         return false;
  71                 }
  72
  73                 // Get all query values
  74                 $queryVals = $context->getRequest()->getValues();
  75                 foreach ( $queryVals as $query => $val ) {
  76                         if ( $query === 'title' || $query === 'curid' ) {
  77                                 continue; // note: curid sets title
  78                         // Normal page view in query form can have action=view.
  79                         } elseif ( $query === 'action' && in_array( $val, self::cacheablePageActions() ) ) {
  80                                 continue;
  81                         // Below are header setting params
  82                         } elseif ( $query === 'maxage' || $query === 'smaxage' ) {
  83                                 continue;
  84                         }
  85                         return false;
  86                 }
  87                 $user = $context->getUser();
  88                 // Check for non-standard user language; this covers uselang,
  89                 // and extensions for auto-detecting user language.
  90                 $ulang = $context->getLanguage()->getCode();
  91                 $clang = $wgContLang->getCode();
  92                 // Check that there are no other sources of variation
  93                 return !$user->getId() && !$user->getNewtalk() && $ulang == $clang;
  94         }
  95
  96         /**
  97          * Read from cache to context output
  98          * @param $context IContextSource
  99          * @return void
 100          */
 101         public function loadFromFileCache( IContextSource $context ) {
 102                 global $wgMimeType, $wgLanguageCode;
 103
 104                 wfDebug( __METHOD__ . "()\n");
 105                 $filename = $this->cachePath();
 106                 $context->getOutput()->sendCacheControl();
 107                 header( "Content-Type: $wgMimeType; charset=UTF-8" );
 108                 header( "Content-Language: $wgLanguageCode" );
 109                 if ( $this->useGzip() ) {
 110                         if ( wfClientAcceptsGzip() ) {
 111                                 header( 'Content-Encoding: gzip' );
 112                         } else {
 113                                 /* Send uncompressed */
 114                                 readgzfile( $filename );
 115                                 return;
 116                         }
 117                 }
 118                 readfile( $filename );
 119                 $context->getOutput()->disable(); // tell $wgOut that output is taken care of
 120         }
 121
 122         /**
 123          * Save this cache object with the given text.
 124          * Use this as an ob_start() handler.
 125          * @param $text string
 126          * @return bool Whether $wgUseFileCache is enabled
 127          */
 128         public function saveToFileCache( $text ) {
 129                 global $wgUseFileCache;
 130
 131                 if ( !$wgUseFileCache || strlen( $text ) < 512 ) {
 132                         // Disabled or empty/broken output (OOM and PHP errors)
 133                         return $text;
 134                 }
 135
 136                 wfDebug( __METHOD__ . "()\n", false);
 137
 138                 $now = wfTimestampNow();
 139                 if ( $this->useGzip() ) {
 140                         $text = str_replace(
 141                                 '</html>', '<!-- Cached/compressed '.$now." -->\n</html>", $text );
 142                 } else {
 143                         $text = str_replace(
 144                                 '</html>', '<!-- Cached '.$now." -->\n</html>", $text );
 145                 }
 146
 147                 // Store text to FS...
 148                 $compressed = $this->saveText( $text );
 149                 if ( $compressed === false ) {
 150                         return $text; // error
 151                 }
 152
 153                 // gzip output to buffer as needed and set headers...
 154                 if ( $this->useGzip() ) {
 155                         // @TODO: ugly wfClientAcceptsGzip() function - use context!
 156                         if ( wfClientAcceptsGzip() ) {
 157                                 header( 'Content-Encoding: gzip' );
 158                                 return $compressed;
 159                         } else {
 160                                 return $text;
 161                         }
 162                 } else {
 163                         return $text;
 164                 }
 165         }
 166
 167         /**
 168          * Clear the file caches for a page for all actions
 169          * @param $title Title
 170          * @return bool Whether $wgUseFileCache is enabled
 171          */
 172         public static function clearFileCache( Title $title ) {
 173                 global $wgUseFileCache;
 174
 175                 if ( !$wgUseFileCache ) {
 176                         return false;
 177                 }
 178
 179                 foreach ( self::cacheablePageActions() as $type ) {
 180                         $fc = self::newFromTitle( $title, $type );
 181                         $fc->clearCache();
 182                 }
 183
 184                 return true;
 185         }
 186 }