protected function getData($key)
    {
        $path = $this->path($key);
        if (!$this->fileSystem->isFile($path)) {
            return ['data' => null, 'time' => null];
        }

        $content    = $this->fileSystem->get($path);
        $expire     = substr($content, 0, 10);

        if (time() > $expire) {
            $this->delete($key);
            return ['data' => null, 'time' => null];
        }

        $data = unserialize(substr($content, 10));


        return ['data'=>$data, 'time' => ($expire - time())];
    }