includes/cache/HTMLFileCache.php
<?php
/**
* Page view caching in the file system.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Cache
*/
use MediaWiki\Cache\CacheKeyHelper;
use MediaWiki\Cache\FileCacheBase;
use MediaWiki\Context\IContextSource;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Page\PageIdentity;
/**
* Page view caching in the file system.
* The only cacheable actions are "view" and "history". Also special pages
* will not be cached.
*
* @ingroup Cache
*/
class HTMLFileCache extends FileCacheBase {
public const MODE_NORMAL = 0; // normal cache mode
public const MODE_OUTAGE = 1; // fallback cache for DB outages
public const MODE_REBUILD = 2; // background cache rebuild mode
private const CACHEABLE_ACTIONS = [
'view',
'history',
];
/**
* @param PageIdentity|string $page PageIdentity object or prefixed DB key string
* @param string $action
*/
public function __construct( $page, $action ) {
parent::__construct();
if ( !in_array( $action, self::CACHEABLE_ACTIONS ) ) {
throw new InvalidArgumentException( 'Invalid file cache type given.' );
}
$this->mKey = CacheKeyHelper::getKeyForPage( $page );
$this->mType = (string)$action;
$this->mExt = 'html';
}
/**
* Get the base file cache directory
* @return string
*/
protected function cacheDirectory() {
return $this->baseCacheDirectory(); // no subdir for b/c with old cache files
}
/**
* Get the cache type subdirectory (with the trailing slash) or the empty string
* Alter the type -> directory mapping to put action=view cache at the root.
*
* @return string
*/
protected function typeSubdirectory() {
if ( $this->mType === 'view' ) {
return ''; // b/c to not skip existing cache
} else {
return $this->mType . '/';
}
}
/**
* Check if pages can be cached for this request/user
* @param IContextSource $context
* @param int $mode One of the HTMLFileCache::MODE_* constants (since 1.28)
* @return bool
*/
public static function useFileCache( IContextSource $context, $mode = self::MODE_NORMAL ) {
$services = MediaWikiServices::getInstance();
$config = $services->getMainConfig();
if ( !$config->get( MainConfigNames::UseFileCache ) && $mode !== self::MODE_REBUILD ) {
return false;
}
// Get all query values
$queryVals = $context->getRequest()->getValues();
foreach ( $queryVals as $query => $val ) {
if ( $query === 'title' || $query === 'curid' ) {
continue; // note: curid sets title
// Normal page view in query form can have action=view.
} elseif ( $query === 'action' && in_array( $val, self::CACHEABLE_ACTIONS ) ) {
continue;
// Below are header setting params
} elseif ( $query === 'maxage' || $query === 'smaxage' ) {
continue;
// Uselang value is checked below
} elseif ( $query === 'uselang' ) {
continue;
}
return false;
}
$user = $context->getUser();
// Check for non-standard user language; this covers uselang,
// and extensions for auto-detecting user language.
$ulang = $context->getLanguage();
// Check that there are no other sources of variation
if ( $user->isRegistered() ||
!$ulang->equals( $services->getContentLanguage() ) ) {
return false;
}
$userHasNewMessages = $services->getTalkPageNotificationManager()->userHasNewMessages( $user );
if ( ( $mode === self::MODE_NORMAL ) && $userHasNewMessages ) {
return false;
}
// Allow extensions to disable caching
return ( new HookRunner( $services->getHookContainer() ) )->onHTMLFileCache__useFileCache( $context );
}
/**
* Read from cache to context output
* @param IContextSource $context
* @param int $mode One of the HTMLFileCache::MODE_* constants
* @return void
*/
public function loadFromFileCache( IContextSource $context, $mode = self::MODE_NORMAL ) {
wfDebug( __METHOD__ . "()" );
$filename = $this->cachePath();
if ( $mode === self::MODE_OUTAGE ) {
// Avoid DB errors for queries in sendCacheControl()
$context->getTitle()->resetArticleID( 0 );
}
$context->getOutput()->sendCacheControl();
header( "Content-Type: {$this->options->get( MainConfigNames::MimeType )}; charset=UTF-8" );
header( 'Content-Language: ' .
MediaWikiServices::getInstance()->getContentLanguage()->getHtmlCode() );
if ( $this->useGzip() ) {
if ( wfClientAcceptsGzip() ) {
header( 'Content-Encoding: gzip' );
readfile( $filename );
} else {
/* Send uncompressed */
wfDebug( __METHOD__ . " uncompressing cache file and sending it" );
readgzfile( $filename );
}
} else {
readfile( $filename );
}
$context->getOutput()->disable(); // tell $wgOut that output is taken care of
}
/**
* Save this cache object with the given text.
* Use this as an ob_start() handler.
*
* Normally this is only registered as a handler if $wgUseFileCache is on.
* If can be explicitly called by rebuildFileCache.php when it takes over
* handling file caching itself, disabling any automatic handling the
* process.
*
* @param string $text
* @return string|bool The annotated $text or false on error
*/
public function saveToFileCache( $text ) {
if ( strlen( $text ) < 512 ) {
// Disabled or empty/broken output (OOM and PHP errors)
return $text;
}
wfDebug( __METHOD__ . "()\n", 'private' );
$now = wfTimestampNow();
if ( $this->useGzip() ) {
$text = str_replace(
'</html>', '<!-- Cached/compressed ' . $now . " -->\n</html>", $text );
} else {
$text = str_replace(
'</html>', '<!-- Cached ' . $now . " -->\n</html>", $text );
}
// Store text to FS...
$compressed = $this->saveText( $text );
if ( $compressed === false ) {
return $text; // error
}
// gzip output to buffer as needed and set headers...
// @todo Ugly wfClientAcceptsGzip() function - use context!
if ( $this->useGzip() && wfClientAcceptsGzip() ) {
header( 'Content-Encoding: gzip' );
return $compressed;
}
return $text;
}
/**
* Clear the file caches for a page for all actions
*
* @param PageIdentity|string $page PageIdentity object or prefixed DB key string
* @return bool Whether $wgUseFileCache is enabled
*/
public static function clearFileCache( $page ) {
$config = MediaWikiServices::getInstance()->getMainConfig();
if ( !$config->get( MainConfigNames::UseFileCache ) ) {
return false;
}
foreach ( self::CACHEABLE_ACTIONS as $type ) {
$fc = new self( $page, $type );
$fc->clearCache();
}
return true;
}
}