1 files changed, 198 insertions, 0 deletions
diff --git a/lib/classes/cache/RedisCache.php b/lib/classes/cache/RedisCache.php
new file mode 100644
index 0000000..a78f751
--- /dev/null
+++ b/lib/classes/cache/RedisCache.php
@@ -0,0 +1,198 @@
+<?php
+
+namespace Studip\Cache;
+
+use BadMethodCallException;
+use Config;
+use DateTime;
+use Exception;
+use Psr\Cache\CacheItemInterface;
+use Redis;
+use RedisException;
+
+/**
+ * Cache implementation using redis.
+ *
+ * @author      Jan-Hendrik Willms <tleilax+studip@gmail.com>
+ * @license     GPL2 or any later version
+ * @package     studip
+ * @subpackage  cache
+ * @since       Stud.IP 5.0
+ */
+class RedisCache extends Cache
+{
+    use KeyTrait;
+
+    private $redis;
+
+    /**
+     * @return string A translateable display name for this cache class.
+     */
+    public static function getDisplayName(): string
+    {
+        return _('Redis');
+    }
+
+    /**
+     * Construct a cache instance.
+     *
+     * @param string $hostname Hostname of redis server
+     * @param int    $port     Port of redis server
+     * @param string $auth     Optional auth token/password
+     *
+     * @throws RedisException
+     */
+    public function __construct($hostname, $port, string $auth = '')
+    {
+        if (!extension_loaded('redis')) {
+            throw new Exception('Redis extension missing.');
+        }
+
+        $this->redis = new Redis();
+        $status = $this->redis->connect($hostname, $port, 1);
+
+        if (!$status) {
+            throw new Exception('Could not add cache.');
+        }
+
+        if ($auth !== '') {
+            $this->redis->auth($auth);
+        }
+    }
+
+    /**
+     * Returns the instance of the redis server connection.
+     *
+     * @return Redis instance
+     */
+    public function getRedis()
+    {
+        return $this->redis;
+    }
+
+    /**
+     * Expire item from the cache.
+     *
+     * Example:
+     *
+     *   # expires foo
+     *   $cache->expire('foo');
+     *
+     * @param   string $arg a single key.
+     */
+    public function expire($arg)
+    {
+        $key = $this->getCacheKey($arg);
+        $this->redis->unlink($key);
+    }
+
+    /**
+     * Expire all items from the cache.
+     */
+    public function flush()
+    {
+        $pattern = $this->getCacheKey('*');
+        foreach ($this->redis->keys($pattern) as $key) {
+            $this->redis->unlink($key);
+        }
+    }
+
+    /**
+     * @param string $method Method to call
+     * @param array $args Arguments to pass
+     * @return false|mixed
+     */
+    public function __call($method, $args)
+    {
+        if (is_callable([$this->redis, $method])) {
+            return call_user_func_array([$this->redis, $method], $args);
+        }
+        throw new BadMethodCallException("Method {$method} does not exist");
+    }
+
+    /**
+     * Return statistics.
+     *
+     * @StudipCache::getStats()
+     *
+     * @return array|array[]
+     */
+    public function getStats(): array
+    {
+        $stats = $this->redis->info();
+        $stats['size'] = count($this->redis->keys($this->getCacheKey('*')));
+        return ["{$this->redis->getHost()}:{$this->redis->getPort()}" => $stats];
+    }
+
+    /*
+     * Return the Vue component name and props that handle configuration.
+     *
+     * @see StudipCache::getConfig()
+     *
+     * @return array
+     */
+    public static function getConfig(): array
+    {
+        $currentCache = Config::get()->SYSTEMCACHE;
+
+        // Set default config for this cache
+        $currentConfig = [
+            'hostname' => '',
+            'port' => null
+        ];
+
+        // If this cache is set as system cache, use config from global settings.
+        if ($currentCache['type'] == __CLASS__) {
+            $currentConfig = $currentCache['config'];
+            $currentConfig['port'] = $currentConfig['port'] ? (int) $currentConfig['port'] : null;
+        }
+
+        return [
+            'component' => 'RedisCacheConfig',
+            'props' => $currentConfig
+        ];
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getItem(string $key): CacheItemInterface
+    {
+        $item = new Item($key);
+        $real_key = $this->getCacheKey($key);
+        $result = $this->redis->get($real_key);
+        if ($result === null) {
+            return $item;
+        }
+        $item->setHit();
+        $item->set(unserialize($result));
+        $expiration = new DateTime();
+        $expiration->setTimestamp($this->redis->expiretime($real_key));
+        $item->expiresAt($expiration);
+        return $item;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function hasItem(string $key): bool
+    {
+        $real_key = $this->getCacheKey($key);
+        return $this->redis->get($real_key) !== null;
+    }
+
+    /**
+     * @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 $this->redis->setEx($real_key, $expiration, serialize($item->get()));
+    }
+}