Rename *CacheDriver to *Cache because they don't act as driver anymore

src/Core/Cache/MemcachedCache.php

@@ -0,0 +1,154 @@
+<?php
+
+namespace Friendica\Core\Cache;
+
+use Exception;
+use Friendica\Core\Cache;
+use Friendica\Core\Config\Configuration;
+use Memcached;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Memcached Cache
+ *
+ * @author Hypolite Petovan <hypolite@mrpetovan.com>
+ */
+class MemcachedCache extends AbstractCache implements IMemoryCache
+{
+	use TraitCompareSet;
+	use TraitCompareDelete;
+
+	/**
+	 * @var \Memcached
+	 */
+	private $memcached;
+
+	/**
+	 * @var LoggerInterface
+	 */
+	private $logger;
+
+	/**
+	 * Due to limitations of the INI format, the expected configuration for Memcached servers is the following:
+	 * array {
+	 *   0 => "hostname, port(, weight)",
+	 *   1 => ...
+	 * }
+	 *
+	 * @param array $memcached_hosts
+	 * @throws \Exception
+	 */
+	public function __construct(string $hostname, Configuration $config, LoggerInterface $logger)
+	{
+		if (!class_exists('Memcached', false)) {
+			throw new Exception('Memcached class isn\'t available');
+		}
+
+		parent::__construct($hostname);
+
+		$this->logger = $logger;
+
+		$this->memcached = new Memcached();
+
+		$memcached_hosts = $config->get('system', 'memcached_hosts');
+
+		array_walk($memcached_hosts, function (&$value) {
+			if (is_string($value)) {
+				$value = array_map('trim', explode(',', $value));
+			}
+		});
+
+		$this->memcached->addServers($memcached_hosts);
+
+		if (count($this->memcached->getServerList()) == 0) {
+			throw new Exception('Expected Memcached servers aren\'t available, config:' . var_export($memcached_hosts, true));
+		}
+	}
+
+	/**
+	 * (@inheritdoc)
+	 */
+	public function getAllKeys($prefix = null)
+	{
+		$keys = $this->getOriginalKeys($this->memcached->getAllKeys());
+
+		if ($this->memcached->getResultCode() == Memcached::RES_SUCCESS) {
+			return $this->filterArrayKeysByPrefix($keys, $prefix);
+		} else {
+			$this->logger->debug('Memcached \'getAllKeys\' failed', ['result' =>  $this->memcached->getResultMessage()]);
+			return [];
+		}
+	}
+
+	/**
+	 * (@inheritdoc)
+	 */
+	public function get($key)
+	{
+		$return = null;
+		$cachekey = $this->getCacheKey($key);
+
+		// We fetch with the hostname as key to avoid problems with other applications
+		$value = $this->memcached->get($cachekey);
+
+		if ($this->memcached->getResultCode() === Memcached::RES_SUCCESS) {
+			$return = $value;
+		} else {
+			$this->logger->debug('Memcached \'get\' failed', ['result' =>  $this->memcached->getResultMessage()]);
+		}
+
+		return $return;
+	}
+
+	/**
+	 * (@inheritdoc)
+	 */
+	public function set($key, $value, $ttl = Cache::FIVE_MINUTES)
+	{
+		$cachekey = $this->getCacheKey($key);
+
+		// We store with the hostname as key to avoid problems with other applications
+		if ($ttl > 0) {
+			return $this->memcached->set(
+				$cachekey,
+				$value,
+				$ttl
+			);
+		} else {
+			return $this->memcached->set(
+				$cachekey,
+				$value
+			);
+		}
+	}
+
+	/**
+	 * (@inheritdoc)
+	 */
+	public function delete($key)
+	{
+		$cachekey = $this->getCacheKey($key);
+		return $this->memcached->delete($cachekey);
+	}
+
+	/**
+	 * (@inheritdoc)
+	 */
+	public function clear($outdated = true)
+	{
+		if ($outdated) {
+			return true;
+		} else {
+			return $this->memcached->flush();
+		}
+	}
+
+	/**
+	 * (@inheritdoc)
+	 */
+	public function add($key, $value, $ttl = Cache::FIVE_MINUTES)
+	{
+		$cachekey = $this->getCacheKey($key);
+		return $this->memcached->add($cachekey, $value, $ttl);
+	}
+}