protected function convertParamsToQuery(array $params)
    {
        $query = array();

        foreach ($params as $key => $val) {
            if (is_array($val)) {
                $val = implode(',', $val);
            } elseif ($val instanceof \DateTime) {
                $val = $val->format('Y-m-d');
            } elseif (is_bool($val)) {
                if ($val) {
                    $val = 1;
                } else {
                    continue;
                }
            } else {
                $val = urlencode($val);
            }
            $query[] = $key . '=' . $val;
        }

        return implode('&', $query);
    }