Redis:

- added support for redis server:

// Required to actually have this cache driver active:
$a->config['system']['cache_driver'] = 'redis';

// ---- OPTIONAL/DEFAULT: ----
$a->config['system']['redis_host'] = '127.0.0.1';
$a->config['system']['redis_port'] = 6379;

Signed-off-by: Roland Häder <roland@mxchange.org>

src/Core/Cache.php

@@ -40,6 +40,12 @@ class Cache extends \Friendica\BaseObject
 
 				self::$driver = new Cache\MemcachedCacheDriver($memcached_hosts);
 				break;
+			case 'redis':
+				$redis_host = Config::get('system', 'redis_host', '127.0.0.1');
+				$redis_port = Config::get('system', 'redis_port', 6379);
+
+				self::$driver = new Cache\RedisCacheDriver($redis_host, $redis_port);
+				break;
 			default:
 				self::$driver = new Cache\DatabaseCacheDriver();
 		}

src/Core/Cache/RedisCacheDriver.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace Friendica\Core\Cache;
+
+use Friendica\BaseObject;
+use Friendica\Core\Cache;
+
+/**
+ * Redis Cache Driver. This driver is based on Memcache driver
+ *
+ * @author Hypolite Petovan <mrpetovan@gmail.com>
+ * @author Roland Haeder <roland@mxchange.org>
+ */
+class RedisCacheDriver extends BaseObject implements ICacheDriver
+{
+	/**
+	 * @var Redis
+	 */
+	private $redis;
+
+	public function __construct($redis_host, $redis_port)
+	{
+		if (!class_exists('Redis', false)) {
+			throw new \Exception('Redis class isn\'t available');
+		}
+
+		$this->redis = new \Redis();
+
+		if (!$this->redis->connect($redis_host, $redis_port)) {
+			throw new \Exception('Expected Redis server at ' . $redis_host . ':' . $redis_port . ' isn\'t available');
+		}
+	}
+
+	public function get($key)
+	{
+		$return = null;
+
+		// We fetch with the hostname as key to avoid problems with other applications
+		$cached = $this->redis->get(self::getApp()->get_hostname() . ':' . $key);
+
+		// @see http://php.net/manual/en/redis.get.php#84275
+		if (is_bool($cached) || is_double($cached) || is_long($cached)) {
+			return $return;
+		}
+
+		$value = @unserialize($cached);
+
+		// Only return a value if the serialized value is valid.
+		// We also check if the db entry is a serialized
+		// boolean 'false' value (which we want to return).
+		if ($cached === serialize(false) || $value !== false) {
+			$return = $value;
+		}
+
+		return $return;
+	}
+
+	public function set($key, $value, $duration = Cache::MONTH)
+	{
+		// We store with the hostname as key to avoid problems with other applications
+		return $this->redis->set(
+			self::getApp()->get_hostname() . ":" . $key,
+			serialize($value),
+			time() + $duration
+		);
+	}
+
+	public function delete($key)
+	{
+		return $this->redis->delete($key);
+	}
+
+	public function clear()
+	{
+		return true;
+	}
+}