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lib/pkp/classes/cache/CacheManager.php

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+<?php
+
+/**
+ * @file classes/cache/CacheManager.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @ingroup cache
+ *
+ * @see GenericCache
+ *
+ * @brief Provides cache management functions.
+ *
+ */
+
+namespace PKP\cache;
+
+use PKP\config\Config;
+use PKP\core\Core;
+use PKP\core\Registry;
+
+define('CACHE_TYPE_FILE', 1);
+define('CACHE_TYPE_OBJECT', 2);
+
+class CacheManager
+{
+    /**
+     * Get the static instance of the cache manager.
+     *
+     * @return CacheManager
+     */
+    public static function getManager()
+    {
+        $manager = & Registry::get('cacheManager', true, null);
+        if ($manager === null) {
+            $manager = new CacheManager();
+        }
+        return $manager;
+    }
+
+    /**
+     * Get a file cache.
+     *
+     * @param string $context
+     * @param string $cacheId
+     * @param callable $fallback
+     *
+     * @return FileCache
+     */
+    public function getFileCache($context, $cacheId, $fallback)
+    {
+        return new FileCache(
+            $context,
+            $cacheId,
+            $fallback,
+            $this->getFileCachePath()
+        );
+    }
+
+    public function getObjectCache($context, $cacheId, $fallback)
+    {
+        return $this->getCache($context, $cacheId, $fallback, CACHE_TYPE_OBJECT);
+    }
+
+    public function getCacheImplementation($type)
+    {
+        switch ($type) {
+            case CACHE_TYPE_FILE: return 'file';
+            case CACHE_TYPE_OBJECT: return Config::getVar('cache', 'object_cache');
+            default: return null;
+        }
+    }
+
+    /**
+     * Get a cache.
+     *
+     * @param string $context
+     * @param string $cacheId
+     * @param ?callable $fallback
+     * @param string $type Type of cache: CACHE_TYPE_...
+     *
+     * @return GenericCache
+     */
+    public function getCache($context, $cacheId, $fallback, $type = CACHE_TYPE_FILE)
+    {
+        switch ($this->getCacheImplementation($type)) {
+            case 'xcache':
+                $cache = new \PKP\cache\XCacheCache(
+                    $context,
+                    $cacheId,
+                    $fallback
+                );
+                break;
+            case 'apc':
+                $cache = new \PKP\cache\APCCache(
+                    $context,
+                    $cacheId,
+                    $fallback
+                );
+                break;
+            case 'memcache':
+                $cache = new \PKP\cache\MemcacheCache(
+                    $context,
+                    $cacheId,
+                    $fallback,
+                    Config::getVar('cache', 'memcache_hostname'),
+                    Config::getVar('cache', 'memcache_port')
+                );
+                break;
+            case '': // Provide a default if not specified
+            case 'file':
+                $cache = $this->getFileCache($context, $cacheId, $fallback);
+                break;
+            case 'none':
+                $cache = new \PKP\cache\GenericCache(
+                    $context,
+                    $cacheId,
+                    $fallback
+                );
+                break;
+            default:
+                exit("Unknown cache type \"{$type}\"!\n");
+        }
+        return $cache;
+    }
+
+    /**
+     * Get the path in which file caches will be stored.
+     *
+     * @return string The full path to the file cache directory
+     */
+    public static function getFileCachePath()
+    {
+        return Core::getBaseDir() . '/cache';
+    }
+
+    /**
+     * Flush an entire context, if specified, or
+     * the whole cache.
+     *
+     * @param string $context The context to flush, if only one is to be flushed
+     * @param string $type The type of cache to flush
+     */
+    public function flush($context = null, $type = CACHE_TYPE_FILE)
+    {
+        $cacheImplementation = $this->getCacheImplementation($type);
+        switch ($cacheImplementation) {
+            case 'xcache':
+            case 'apc':
+            case 'memcache':
+                $junkCache = $this->getCache($context, null, null);
+                $junkCache->flush();
+                break;
+            case 'file':
+                $filePath = $this->getFileCachePath();
+                $files = glob("{$filePath}/fc-" . (isset($context) ? $context . '-' : '') . '*.php');
+                foreach ($files as $file) {
+                    @unlink($file);
+                }
+                break;
+            case '':
+            case 'none':
+                // Nothing necessary.
+                break;
+            default:
+                exit("Unknown cache type \"{$type}\"!\n");
+        }
+    }
+}