1 files changed, 151 insertions, 0 deletions
diff --git a/lib/classes/cache/MemcachedCache.php b/lib/classes/cache/MemcachedCache.php
new file mode 100644
index 0000000..1c4b685
--- /dev/null
+++ b/lib/classes/cache/MemcachedCache.php
@@ -0,0 +1,151 @@
+<?php
+
+namespace Studip\Cache;
+
+use Memcached;
+use Psr\Cache\CacheItemInterface;
+
+/**
+ * Cache implementation using memcached.
+ *
+ * @author    Marcus Lunzenauer <mlunzena@uos.de>
+ * @copyright (c) Authors
+ * @license GPL2 or any later version
+ * @since   5.0
+ */
+class MemcachedCache extends Cache
+{
+    use KeyTrait;
+
+    private Memcached $memcache;
+
+    /**
+     * @return string A translateable display name for this cache class.
+     */
+    public static function getDisplayName(): string
+    {
+        return _('Memcached');
+    }
+
+    public function __construct($servers)
+    {
+        if (!extension_loaded('memcached')) {
+            throw new \Exception('Memcache extension missing.');
+        }
+
+        $prefix = \Config::get()->STUDIP_INSTALLATION_ID;
+        $this->memcache = new Memcached('studip' . ($prefix ? '-' . $prefix : ''));
+
+        if (count($this->memcache->getServerList()) === 0) {
+            foreach ($servers as $server) {
+                $status = $this->memcache->addServer($server['hostname'], (int) $server['port']);
+
+                if (!$status) {
+                    throw new \Exception("Could not add server: {$server['hostname']} @ port {$server['port']}");
+                }
+            }
+        }
+    }
+
+    /**
+     * Expire item from the cache.
+     *
+     * Example:
+     *
+     *   # expires foo
+     *   $cache->expire('foo');
+     *
+     * @param   string $arg a single key.
+     * @returns void
+     */
+    public function expire($arg)
+    {
+        $key = $this->getCacheKey($arg);
+        $this->memcache->delete($key);
+    }
+
+    /**
+     * Expire all items from the cache.
+     */
+    public function flush()
+    {
+        $this->memcache->flush();
+    }
+
+    /**
+     * Return statistics.
+     *
+     * @StudipCache::getStats()
+     *
+     * @return array|array[]
+     */
+    public function getStats(): array
+    {
+        return $this->memcache->getStats();
+    }
+
+    /**
+     * Return the Vue component name and props that handle configuration.
+     *
+     * @see Cache::getConfig()
+     *
+     * @return array
+     */
+    public static function getConfig(): array
+    {
+        $currentCache = \Config::get()->SYSTEMCACHE;
+
+        // Set default config for this cache
+        $currentConfig = [
+            'servers' => []
+        ];
+
+        // If this cache is set as system cache, use config from global settings.
+        if ($currentCache['type'] == __CLASS__) {
+            $currentConfig = $currentCache['config'];
+        }
+
+        return [
+            'component' => 'MemcachedCacheConfig',
+            'props' => $currentConfig
+        ];
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getItem(string $key): CacheItemInterface
+    {
+        $item = new Item($key);
+        $value = $this->memcache->get($this->getCacheKey($key));
+        if ($this->memcache->getResultCode() !== Memcached::RES_NOTFOUND) {
+            // Set the value, even if it is the boolean value false:
+            $item->setHit();
+            $item->set($value);
+        }
+        return $item;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function hasItem(string $key): bool
+    {
+        return $this->memcache->checkKey($this->getCacheKey($key));
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function save(CacheItemInterface $item): bool
+    {
+        $expiration = $this->getExpiration($item);
+        if ($expiration < 1) {
+            // The item would expire immediately.
+            return false;
+        }
+
+        $real_key = $this->getCacheKey($item->getKey());
+        return $this->memcache->set($real_key, $item->get(), $expiration);
+    }
+}