spring gateway自定义过滤器

川长思鸟来 2022-11-11 05:26 75阅读 0赞

## 自定义Global Filter ##

package com.zsp.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;
    
    @Component
    @Slf4j
    public class MyGateWayFilter implements Ordered, GlobalFilter { 
    
        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) { 
            log.info("********************come in MyGateWayFilter:"+new Date());
            String uname = exchange.getRequest().getQueryParams().getFirst("uname");
            if (uname==null)
            { 
                log.info("输入的用户名错误，请重新输入");
                //设置响应状态码为未授权
                exchange.getResponse().setStatusCode(HttpStatus.NOT_ACCEPTABLE);//给人家一个回应
                return exchange.getResponse().setComplete();
            }
            return chain.filter(exchange);
        }
    
    	/* *过滤器存在优先级，order越大，优先级越低 */
        @Override
        public int getOrder() { 
            return 0;  //代表优先级
        }
    }

如上请求参数必须携带uname，否则将不能访问。

如上是加了@componet注解，即不用配置，已在容器管理生命周期。

## 自定义Gateway Filter ##

/** * 此过滤器功能为计算请求完成时间 */
    public class MyFilter implements GatewayFilter, Ordered { 
    
        private static final String ELAPSED_TIME_BEGIN = "elapsedTimeBegin";
    
        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) { 
            exchange.getAttributes().put(ELAPSED_TIME_BEGIN, System.currentTimeMillis());
            return chain.filter(exchange).then(
                    Mono.fromRunnable(() -> { 
                        Long startTime = exchange.getAttribute(ELAPSED_TIME_BEGIN);
                        if (startTime != null) { 
                            System.out.println(exchange.getRequest().getURI().getRawPath() + ": " + (System.currentTimeMillis() - startTime) + "ms");
                        }
                    })
            );
        }
    
        /* *过滤器存在优先级，order越大，优先级越低 */
        @Override
        public int getOrder() { 
            return Ordered.LOWEST_PRECEDENCE;
        }
    }

这种过滤器需要配合编码的方式

@Bean
    public RouteLocator routeLocator(RouteLocatorBuilder builder) { 
         return builder.routes().route(r ->
                 r.path("/aa")
                         //转发路由
                         .uri("http://localhost:8080/provider/test")
                         //注册自定义过滤器
                         .filters(new MyFilter())
                        //给定id
                        .id("user-service"))
                        .build();
    }

## 自定义Gateway Filter Factory ##

自定义过滤器工厂需要继承AbstractGatewayFilterFactory

@Component
    public class AuthorizeGatewayFilterFactory extends AbstractGatewayFilterFactory<AuthorizeGatewayFilterFactory.Config> { 
    
        private static final Log logger = LogFactory.getLog(AuthorizeGatewayFilterFactory.class);
    
        private static final String AUTHORIZE_TOKEN = "token";
        private static final String AUTHORIZE_UID = "uid";
    
        @Autowired
        private StringRedisTemplate stringRedisTemplate;
    
        public AuthorizeGatewayFilterFactory() { 
            super(Config.class);
            logger.info("Loaded GatewayFilterFactory [Authorize]");
        }
    
        @Override
        public List<String> shortcutFieldOrder() { 
            return Arrays.asList("enabled");
        }
    
        @Override
        public GatewayFilter apply(AuthorizeGatewayFilterFactory.Config config) { 
            return (exchange, chain) -> { 
                if (!config.isEnabled()) { 
                    return chain.filter(exchange);
                }
    
                ServerHttpRequest request = exchange.getRequest();
                HttpHeaders headers = request.getHeaders();
                String token = headers.getFirst(AUTHORIZE_TOKEN);
                String uid = headers.getFirst(AUTHORIZE_UID);
                if (token == null) { 
                    token = request.getQueryParams().getFirst(AUTHORIZE_TOKEN);
                }
                if (uid == null) { 
                    uid = request.getQueryParams().getFirst(AUTHORIZE_UID);
                }
    
                ServerHttpResponse response = exchange.getResponse();
                if (StringUtils.isEmpty(token) || StringUtils.isEmpty(uid)) { 
                    response.setStatusCode(HttpStatus.UNAUTHORIZED);
                    return response.setComplete();
                }
                String authToken = stringRedisTemplate.opsForValue().get(uid);
                if (authToken == null || !authToken.equals(token)) { 
                    response.setStatusCode(HttpStatus.UNAUTHORIZED);
                    return response.setComplete();
                }
                return chain.filter(exchange);
            };
        }
    
        public static class Config { 
            // 控制是否开启认证
            private boolean enabled;
    
            public Config() {  }
    
            public boolean isEnabled() { 
                return enabled;
            }
    
            public void setEnabled(boolean enabled) { 
                this.enabled = enabled;
            }
        }
    }

在application.yml配置使用

# 网关路由配置 #

spring:
      cloud:
        gateway:
          routes:
          - id: user-center-service
            uri: http://localhost:8080/api/user/list
            predicates:
            - Path=/user/list
            filters:
            # 关键在下面一句，值为true则开启认证，false则不开启
            # 这种配置方式和spring cloud gateway内置的GatewayFilterFactory一致
            - Authorize=true

文章参考 [https://cloud.tencent.com/developer/article/1762151][https_cloud.tencent.com_developer_article_1762151]

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[https_cloud.tencent.com_developer_article_1762151]: https://cloud.tencent.com/developer/article/1762151
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