--- /dev/null
+<?php
+/**
+ * Data storage 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
+ */
+
+/**
+ * Base class for data storage in the file system.
+ *
+ * @ingroup Cache
+ */
+abstract class FileCacheBase {
+ protected $mKey;
+ protected $mType = 'object';
+ protected $mExt = 'cache';
+ protected $mFilePath;
+ protected $mUseGzip;
+ /* lazy loaded */
+ protected $mCached;
+
+ /* @todo configurable? */
+ const MISS_FACTOR = 15; // log 1 every MISS_FACTOR cache misses
+ const MISS_TTL_SEC = 3600; // how many seconds ago is "recent"
+
+ protected function __construct() {
+ global $wgUseGzip;
+
+ $this->mUseGzip = (bool)$wgUseGzip;
+ }
+
+ /**
+ * Get the base file cache directory
+ * @return string
+ */
+ final protected function baseCacheDirectory() {
+ global $wgFileCacheDirectory;
+
+ return $wgFileCacheDirectory;
+ }
+
+ /**
+ * Get the base cache directory (not specific to this file)
+ * @return string
+ */
+ abstract protected function cacheDirectory();
+
+ /**
+ * Get the path to the cache file
+ * @return string
+ */
+ protected function cachePath() {
+ if ( $this->mFilePath !== null ) {
+ return $this->mFilePath;
+ }
+
+ $dir = $this->cacheDirectory();
+ # Build directories (methods include the trailing "/")
+ $subDirs = $this->typeSubdirectory() . $this->hashSubdirectory();
+ # Avoid extension confusion
+ $key = str_replace( '.', '%2E', urlencode( $this->mKey ) );
+ # Build the full file path
+ $this->mFilePath = "{$dir}/{$subDirs}{$key}.{$this->mExt}";
+ if ( $this->useGzip() ) {
+ $this->mFilePath .= '.gz';
+ }
+
+ return $this->mFilePath;
+ }
+
+ /**
+ * Check if the cache file exists
+ * @return bool
+ */
+ public function isCached() {
+ if ( $this->mCached === null ) {
+ $this->mCached = file_exists( $this->cachePath() );
+ }
+
+ return $this->mCached;
+ }
+
+ /**
+ * Get the last-modified timestamp of the cache file
+ * @return string|bool TS_MW timestamp
+ */
+ public function cacheTimestamp() {
+ $timestamp = filemtime( $this->cachePath() );
+
+ return ( $timestamp !== false )
+ ? wfTimestamp( TS_MW, $timestamp )
+ : false;
+ }
+
+ /**
+ * Check if up to date cache file exists
+ * @param string $timestamp MW_TS timestamp
+ *
+ * @return bool
+ */
+ public function isCacheGood( $timestamp = '' ) {
+ global $wgCacheEpoch;
+
+ if ( !$this->isCached() ) {
+ return false;
+ }
+
+ $cachetime = $this->cacheTimestamp();
+ $good = ( $timestamp <= $cachetime && $wgCacheEpoch <= $cachetime );
+ wfDebug( __METHOD__ .
+ ": cachetime $cachetime, touched '{$timestamp}' epoch {$wgCacheEpoch}, good $good\n" );
+
+ return $good;
+ }
+
+ /**
+ * Check if the cache is gzipped
+ * @return bool
+ */
+ protected function useGzip() {
+ return $this->mUseGzip;
+ }
+
+ /**
+ * Get the uncompressed text from the cache
+ * @return string
+ */
+ public function fetchText() {
+ if ( $this->useGzip() ) {
+ $fh = gzopen( $this->cachePath(), 'rb' );
+
+ return stream_get_contents( $fh );
+ } else {
+ return file_get_contents( $this->cachePath() );
+ }
+ }
+
+ /**
+ * Save and compress text to the cache
+ * @param string $text
+ * @return string|false Compressed text
+ */
+ public function saveText( $text ) {
+ if ( $this->useGzip() ) {
+ $text = gzencode( $text );
+ }
+
+ $this->checkCacheDirs(); // build parent dir
+ if ( !file_put_contents( $this->cachePath(), $text, LOCK_EX ) ) {
+ wfDebug( __METHOD__ . "() failed saving " . $this->cachePath() . "\n" );
+ $this->mCached = null;
+
+ return false;
+ }
+
+ $this->mCached = true;
+
+ return $text;
+ }
+
+ /**
+ * Clear the cache for this page
+ * @return void
+ */
+ public function clearCache() {
+ MediaWiki\suppressWarnings();
+ unlink( $this->cachePath() );
+ MediaWiki\restoreWarnings();
+ $this->mCached = false;
+ }
+
+ /**
+ * Create parent directors of $this->cachePath()
+ * @return void
+ */
+ protected function checkCacheDirs() {
+ wfMkdirParents( dirname( $this->cachePath() ), null, __METHOD__ );
+ }
+
+ /**
+ * Get the cache type subdirectory (with trailing slash)
+ * An extending class could use that method to alter the type -> directory
+ * mapping. @see HTMLFileCache::typeSubdirectory() for an example.
+ *
+ * @return string
+ */
+ protected function typeSubdirectory() {
+ return $this->mType . '/';
+ }
+
+ /**
+ * Return relative multi-level hash subdirectory (with trailing slash)
+ * or the empty string if not $wgFileCacheDepth
+ * @return string
+ */
+ protected function hashSubdirectory() {
+ global $wgFileCacheDepth;
+
+ $subdir = '';
+ if ( $wgFileCacheDepth > 0 ) {
+ $hash = md5( $this->mKey );
+ for ( $i = 1; $i <= $wgFileCacheDepth; $i++ ) {
+ $subdir .= substr( $hash, 0, $i ) . '/';
+ }
+ }
+
+ return $subdir;
+ }
+
+ /**
+ * Roughly increments the cache misses in the last hour by unique visitors
+ * @param WebRequest $request
+ * @return void
+ */
+ public function incrMissesRecent( WebRequest $request ) {
+ if ( mt_rand( 0, self::MISS_FACTOR - 1 ) == 0 ) {
+ $cache = ObjectCache::getLocalClusterInstance();
+ # Get a large IP range that should include the user even if that
+ # person's IP address changes
+ $ip = $request->getIP();
+ if ( !IP::isValid( $ip ) ) {
+ return;
+ }
+ $ip = IP::isIPv6( $ip )
+ ? IP::sanitizeRange( "$ip/32" )
+ : IP::sanitizeRange( "$ip/16" );
+
+ # Bail out if a request already came from this range...
+ $key = $cache->makeKey( static::class, 'attempt', $this->mType, $this->mKey, $ip );
+ if ( $cache->get( $key ) ) {
+ return; // possibly the same user
+ }
+ $cache->set( $key, 1, self::MISS_TTL_SEC );
+
+ # Increment the number of cache misses...
+ $key = $this->cacheMissKey( $cache );
+ if ( $cache->get( $key ) === false ) {
+ $cache->set( $key, 1, self::MISS_TTL_SEC );
+ } else {
+ $cache->incr( $key );
+ }
+ }
+ }
+
+ /**
+ * Roughly gets the cache misses in the last hour by unique visitors
+ * @return int
+ */
+ public function getMissesRecent() {
+ $cache = ObjectCache::getLocalClusterInstance();
+
+ return self::MISS_FACTOR * $cache->get( $this->cacheMissKey( $cache ) );
+ }
+
+ /**
+ * @param BagOStuff $cache Instance that the key will be used with
+ * @return string
+ */
+ protected function cacheMissKey( BagOStuff $cache ) {
+ return $cache->makeKey( static::class, 'misses', $this->mType, $this->mKey );
+ }
+}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff