def verify_url
      if not valid_msg_signature(params)
        Rails.logger.debug("#{__FILE__}:#{__LINE__} Failure because signature is invalid")
        render text: "", status: 401
        return
      end
      content, status = Prpcrypt.decrypt(aes_key, params[:echostr], corp_id)
      render text: content, status: status
    end
def verify_url
      if not valid_msg_signature(params)
        Rails.logger.debug("#{__FILE__}:#{__LINE__} Failure because signature is invalid")
        render text: "", status: 401
        return
      end
      content, status = Prpcrypt.decrypt(aes_key, params[:echostr], corp_id)
      render text: content, status: status
    end
验证URL有效性
 TODO: refactor