+++ /dev/null
-<?php
-/**
- * Cache of file objects, wrapping some RepoGroup functions to avoid redundant
- * queries. Loosely inspired by the LinkCache / LinkBatch classes for titles.
- *
- * ISSUE: Merge with RepoGroup?
- *
- * @ingroup FileRepo
- */
-class FileCache {
- var $repoGroup;
- var $cache = array(), $notFound = array();
-
- protected static $instance;
-
- /**
- * Get a FileCache instance. Typically, only one instance of FileCache
- * is needed in a MediaWiki invocation.
- */
- static function singleton() {
- if ( self::$instance ) {
- return self::$instance;
- }
- self::$instance = new FileCache( RepoGroup::singleton() );
- return self::$instance;
- }
-
- /**
- * Destroy the singleton instance, so that a new one will be created next
- * time singleton() is called.
- */
- static function destroySingleton() {
- self::$instance = null;
- }
-
- /**
- * Set the singleton instance to a given object
- */
- static function setSingleton( $instance ) {
- self::$instance = $instance;
- }
-
- /**
- * Construct a group of file repositories.
- * @param RepoGroup $repoGroup
- */
- function __construct( $repoGroup ) {
- $this->repoGroup = $repoGroup;
- }
-
-
- /**
- * Add some files to the cache. This is a fairly low-level function,
- * which most users should not need to call. Note that any existing
- * entries for the same keys will not be replaced. Call clearFiles()
- * first if you need that.
- * @param array $files array of File objects, indexed by DB key
- */
- function addFiles( $files ) {
- wfDebug( "FileCache adding ".count( $files )." files\n" );
- $this->cache += $files;
- }
-
- /**
- * Remove some files from the cache, so that their existence will be
- * rechecked. This is a fairly low-level function, which most users
- * should not need to call.
- * @param array $remove array indexed by DB keys to remove (the values are ignored)
- */
- function clearFiles( $remove ) {
- wfDebug( "FileCache clearing data for ".count( $remove )." files\n" );
- $this->cache = array_diff_keys( $this->cache, $remove );
- $this->notFound = array_diff_keys( $this->notFound, $remove );
- }
-
- /**
- * Mark some DB keys as nonexistent. This is a fairly low-level
- * function, which most users should not need to call.
- * @param array $dbkeys array of DB keys
- */
- function markNotFound( $dbkeys ) {
- wfDebug( "FileCache marking ".count( $dbkeys )." files as not found\n" );
- $this->notFound += array_fill_keys( $dbkeys, true );
- }
-
-
- /**
- * Search the cache for a file.
- * @param mixed $title Title object or string
- * @return File object or false if it is not found
- * @todo Implement searching for old file versions(?)
- */
- function findFile( $title ) {
- if( !( $title instanceof Title ) ) {
- $title = Title::makeTitleSafe( NS_FILE, $title );
- }
- if( !$title ) {
- return false; // invalid title?
- }
-
- $dbkey = $title->getDBkey();
- if( array_key_exists( $dbkey, $this->cache ) ) {
- wfDebug( "FileCache HIT for $dbkey\n" );
- return $this->cache[$dbkey];
- }
- if( array_key_exists( $dbkey, $this->notFound ) ) {
- wfDebug( "FileCache negative HIT for $dbkey\n" );
- return false;
- }
-
- // Not in cache, fall back to a direct query
- $file = $this->repoGroup->findFile( $title );
- if( $file ) {
- wfDebug( "FileCache MISS for $dbkey\n" );
- $this->cache[$dbkey] = $file;
- } else {
- wfDebug( "FileCache negative MISS for $dbkey\n" );
- $this->notFound[$dbkey] = true;
- }
- return $file;
- }
-
- /**
- * Search the cache for multiple files.
- * @param array $titles Title objects or strings to search for
- * @return array of File objects, indexed by DB key
- */
- function findFiles( $titles ) {
- $titleObjs = array();
- foreach ( $titles as $title ) {
- if ( !( $title instanceof Title ) ) {
- $title = Title::makeTitleSafe( NS_FILE, $title );
- }
- if ( $title ) {
- $titleObjs[$title->getDBkey()] = $title;
- }
- }
-
- $result = array_intersect_key( $this->cache, $titleObjs );
-
- $unsure = array_diff_key( $titleObjs, $result, $this->notFound );
- if( $unsure ) {
- wfDebug( "FileCache MISS for ".count( $unsure )." files out of ".count( $titleObjs )."...\n" );
- // XXX: We assume the array returned by findFiles() is
- // indexed by DBkey; this appears to be true, but should
- // be explicitly documented.
- $found = $this->repoGroup->findFiles( $unsure );
- $result += $found;
- $this->addFiles( $found );
- $this->markNotFound( array_keys( array_diff_key( $unsure, $found ) ) );
- }
-
- wfDebug( "FileCache found ".count( $result )." files out of ".count( $titleObjs )."\n" );
- return $result;
- }
-}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff