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, $wgContLang;
  65                 if ( !$wgUseFileCache ) {
  66                         return false;
  67                 }
  68                 // Get all query values
  69                 $queryVals = $context->getRequest()->getValues();
  70                 foreach ( $queryVals as $query => $val ) {
  71                         if ( $query === 'title' || $query === 'curid' ) {
  72                                 continue; // note: curid sets title
  73                         // Normal page view in query form can have action=view.
  74                         // Raw hits for pages also stored, like .css pages for example.
  75                         } elseif ( $query === 'action' && in_array( $val, self::cacheablePageActions() ) ) {
  76                                 continue;
  77                         // Below are header setting params
  78                         } elseif ( $query === 'maxage' || $query === 'smaxage' ) {
  79                                 continue;
  80                         }
  81                         return false;
  82                 }
  83                 $user = $context->getUser();
  84                 // Check for non-standard user language; this covers uselang,
  85                 // and extensions for auto-detecting user language.
  86                 $ulang = $context->getLanguage()->getCode();
  87                 $clang = $wgContLang->getCode();
  88                 // Check that there are no other sources of variation
  89                 return !$wgShowIPinHeader && !$user->getId() && !$user->getNewtalk() && $ulang == $clang;
  90         }
  91
  92         /**
  93          * Read from cache to context output
  94          * @param $context IContextSource
  95          * @return void
  96          */
  97         public function loadFromFileCache( IContextSource $context ) {
  98                 global $wgMimeType, $wgLanguageCode;
  99
 100                 wfDebug( __METHOD__ . "()\n");
 101                 $filename = $this->cachePath();
 102                 $context->getOutput()->sendCacheControl();
 103                 header( "Content-Type: $wgMimeType; charset=UTF-8" );
 104                 header( "Content-Language: $wgLanguageCode" );
 105                 if ( $this->useGzip() ) {
 106                         if ( wfClientAcceptsGzip() ) {
 107                                 header( 'Content-Encoding: gzip' );
 108                         } else {
 109                                 /* Send uncompressed */
 110                                 readgzfile( $filename );
 111                                 return;
 112                         }
 113                 }
 114                 readfile( $filename );
 115                 $context->getOutput()->disable(); // tell $wgOut that output is taken care of
 116         }
 117
 118         /**
 119          * Save this cache object with the given text.
 120          * Use this as an ob_start() handler.
 121          * @param $text string
 122          * @return bool Whether $wgUseFileCache is enabled
 123          */
 124         public function saveToFileCache( $text ) {
 125                 global $wgUseFileCache;
 126
 127                 if ( !$wgUseFileCache || strlen( $text ) < 512 ) {
 128                         // Disabled or empty/broken output (OOM and PHP errors)
 129                         return $text;
 130                 }
 131
 132                 wfDebug( __METHOD__ . "()\n", false);
 133
 134                 $now = wfTimestampNow();
 135                 if ( $this->useGzip() ) {
 136                         $text = str_replace(
 137                                 '</html>', '<!-- Cached/compressed '.$now." -->\n</html>", $text );
 138                 } else {
 139                         $text = str_replace(
 140                                 '</html>', '<!-- Cached '.$now." -->\n</html>", $text );
 141                 }
 142
 143                 // Store text to FS...
 144                 $compressed = $this->saveText( $text );
 145                 if ( $compressed === false ) {
 146                         return $text; // error
 147                 }
 148
 149                 // gzip output to buffer as needed and set headers...
 150                 if ( $this->useGzip() ) {
 151                         // @TODO: ugly wfClientAcceptsGzip() function - use context!
 152                         if ( wfClientAcceptsGzip() ) {
 153                                 header( 'Content-Encoding: gzip' );
 154                                 return $compressed;
 155                         } else {
 156                                 return $text;
 157                         }
 158                 } else {
 159                         return $text;
 160                 }
 161         }
 162
 163         /**
 164          * Clear the file caches for a page for all actions
 165          * @param $title Title
 166          * @return bool Whether $wgUseFileCache is enabled
 167          */
 168         public static function clearFileCache( Title $title ) {
 169                 global $wgUseFileCache;
 170
 171                 if ( !$wgUseFileCache ) {
 172                         return false;
 173                 }
 174
 175                 foreach ( self::cacheablePageActions() as $type ) {
 176                         $fc = self::newFromTitle( $title, $type );
 177                         $fc->clearCache();
 178                 }
 179
 180                 return true;
 181         }
 182 }