Spring Cloud Gateway全局过滤器 GlobalFilter

朱雀 2023-02-26 09:26 130阅读 0赞

## SpringCloud视频教程： ##

[https://ke.qq.com/course/2805647?tuin=a3e3fb1&from\_uin=171851697&from=1000201007][https_ke.qq.com_course_2805647_tuin_a3e3fb1_from_uin_171851697_from_1000201007]

## 个人博客纯净版 ##

[http://www.51ufo.cn/%E5%BE%AE%E6%9C%8D%E5%8A%A1/%E5%88%86%E5%B8%83%E5%BC%8F/2020/07/11/SpringCloud%E5%85%A5%E9%97%A821-Spring-Cloud-Gateway%E5%85%A8%E5%B1%80%E8%BF%87%E6%BB%A4%E5%99%A8-GlobalFilter.html][http_www.51ufo.cn_E5_BE_AE_E6_9C_8D_E5_8A_A1_E5_88_86_E5_B8_83_E5_BC_8F_2020_07_11_SpringCloud_E5_85_A5_E9_97_A821-Spring-Cloud-Gateway_E5_85_A8_E5_B1_80_E8_BF_87_E6_BB_A4_E5_99_A8-GlobalFilter.html]

全局过滤器作用于所有的路由，不需要单独配置，我们可以用它来实现很多统一化处理的业务需求，比如权限认证、IP 限流等等。

单独定义只需要实现 GlobalFilter、Ordered 两个接口就可以了，具体代码如下所示。

@Component
    public class MyFilter implements GlobalFilter, Ordered {
    
        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
            ServerHttpRequest request = exchange.getRequest();
            ServerHttpResponse response = exchange.getResponse();
    
            String token = request.getQueryParams().getFirst("token");
            if(StringUtils.isEmpty(token)) {
                String msg = "token is empty";
                byte[] bits = msg.getBytes(StandardCharsets.UTF_8);
                DataBuffer buffer = response.bufferFactory().wrap(bits);
                //指定编码，否则在浏览器中会中文乱码
                response.getHeaders().add("Content-Type", "text/plain;charset=UTF-8");
                return response.writeWith(Mono.just(buffer));
            }
    
            return chain.filter(exchange);
        }
    
        @Override
        public int getOrder() {
            return 0;
        }
    }

启动每个服务，在浏览器访问[http://localhost/hello?name=xiaoming][http_localhost_hello_name_xiaoming]，返回如下：

token is empty

此时说明全局过滤器生效了，请求被拦截

在浏览器访问[http://localhost/hello?name=xiaoming&token=123][http_localhost_hello_name_xiaoming_token_123]，返回如下：

hello, xiaoming, 我是服务提供者:端口为：8080

此时拦截验证通过，转发到目标服务

本文代码git地址 [https://gitee.com/xmingtx/springcloud-lesson.git][https_gitee.com_xmingtx_springcloud-lesson.git]

[https_ke.qq.com_course_2805647_tuin_a3e3fb1_from_uin_171851697_from_1000201007]: https://ke.qq.com/course/2805647?tuin=a3e3fb1&from_uin=171851697&from=1000201007
[http_www.51ufo.cn_E5_BE_AE_E6_9C_8D_E5_8A_A1_E5_88_86_E5_B8_83_E5_BC_8F_2020_07_11_SpringCloud_E5_85_A5_E9_97_A821-Spring-Cloud-Gateway_E5_85_A8_E5_B1_80_E8_BF_87_E6_BB_A4_E5_99_A8-GlobalFilter.html]: http://www.51ufo.cn/%E5%BE%AE%E6%9C%8D%E5%8A%A1/%E5%88%86%E5%B8%83%E5%BC%8F/2020/07/11/SpringCloud%E5%85%A5%E9%97%A821-Spring-Cloud-Gateway%E5%85%A8%E5%B1%80%E8%BF%87%E6%BB%A4%E5%99%A8-GlobalFilter.html
[http_localhost_hello_name_xiaoming]: http://localhost/hello?name=xiaoming
[http_localhost_hello_name_xiaoming_token_123]: http://localhost/hello?name=xiaoming&token=123
[https_gitee.com_xmingtx_springcloud-lesson.git]: https://gitee.com/xmingtx/springcloud-lesson.git