public function getStorages($type = null)
    {
        if ($type === null) {
            return $this->get('/storage');
        }

        $supportedTypes = array(
            'lvm',
            'nfs',
            'dir',
            'zfs',
            'rbd',
            'iscsi',
            'sheepdog',
            'glusterfs',
            'iscsidirect',
        );

        if (in_array($type, $supportedTypes)) {
            return $this->get('/storage', array(
                'type' => $type,
            ));
        }

        /* If type not found returns null */
        return null;
    }