sentinel限流授权异常信息处理

实现BlockExceptionHandler接口，根据不同的子类型设置不同的异常msg

@Component
public class SentinelExceptionHandler implements BlockExceptionHandler {
    @Override
    public void handle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, BlockException e) throws Exception {
        String msg = "未知异常";
        int status = 429;

        if(e instanceof FlowException){
            msg = "请求被限流了";
        } else if(e instanceof ParamFlowException){
            msg = "请求被热点参数限流了";
        } else if(e instanceof DegradeException){
            msg = "请求被降级了";
        } else if(e instanceof AuthorityException){
            msg = "没有权限访问";
            status = 401;
        }

        httpServletResponse.setContentType("application/json;charset=utf-8");
        httpServletResponse.setStatus(status);
        httpServletResponse.getWriter().println("{msg:" + msg + ",status:" + status + "}");
    }
}