Spring Cloud（十五）：Gateway-Filter的使用

╰+哭是因爲堅強的太久メ 2022-10-22 09:16 24阅读 0赞

## 1. Filter ##

### 1.1 是什么 ###

路由过滤器可用于修改进入的HTTP请求和返回的HTTP响应，路由过滤器只能指定路由进行使用。  
Spring Cloud Gateway内置了多种过滤器，他们都由GatewayFilter的工厂类来产生。

### 1.2 Spring Cloud Gateway的Filter ###

**生命周期**  
在业务逻辑之前：pre  
在业务逻辑之后：post

**种类**  
GatewayFilter：单一  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70]

GlobalFilter:全局  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70 1]

## 2. 常用的GatewayFilter ##

AddRequestParameter  
![在这里插入图片描述][20210325221742807.png]  
过滤器工厂会在匹配的请求头上加上一对请求头，名称为X-Request-red，值为blue

**自定义全局GlobalFilter**  
全局日志记录  
统一网关鉴权

代码

package com.lele.springcloud.filter;
    
    import lombok.extern.slf4j.Slf4j;
    import org.springframework.cloud.gateway.filter.GatewayFilterChain;
    import org.springframework.cloud.gateway.filter.GlobalFilter;
    import org.springframework.core.Ordered;
    import org.springframework.http.HttpStatus;
    import org.springframework.stereotype.Component;
    import org.springframework.web.server.ServerWebExchange;
    import reactor.core.publisher.Mono;
    
    import java.util.Date;
    
    /**
     * @author: lele
     * @date: 2021/3/25 22:24
     * @description:
     */
    @Component
    @Slf4j
    public class MyLogGatewayFilter implements GlobalFilter, Ordered {
        
        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        
            log.info("******come in MyLogGatewayFilter: "+new Date());
            String uname = exchange.getRequest().getQueryParams().getFirst("uname");
            if (uname == null) {
        
                log.info("******用户名为null，非法用户。");
                exchange.getResponse().setStatusCode(HttpStatus.NOT_ACCEPTABLE);
                return exchange.getResponse().setComplete();
            }
            return chain.filter(exchange);
        }
    
        @Override
        public int getOrder() {
        
            return 0;
        }
    }

![在这里插入图片描述][2021032522372392.png]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70 2]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70 3]

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70 1]: /images/20221022/72142303a96c4691b350a71b3b9efe8f.png
[20210325221742807.png]: /images/20221022/580acd9da6f44381a9b7af47753224c7.png
[2021032522372392.png]: /images/20221022/6360b0f880284206af501c0b0359d141.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70 2]: /images/20221022/a99b4ee4f0ad43e49bd561a073fc84b3.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hvdXdhbmxl_size_16_color_FFFFFF_t_70 3]: /images/20221022/9c9fae0a47a44b29b003a5fd62c6e0e7.png