spring-cloud之gateway学习笔记

网关基础配置

1. 添加依赖

   <dependency>
       <groupId>org.springframework.cloud</groupId>
       <artifactId>spring-cloud-starter-gateway</artifactId>
   </dependency>
   <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-actuator</artifactId>
   </dependency>
   

2. 添加配置

   server.port=8080
   spring.application.name=gateway-server
   # 配置路由规则
   # 路由规则1
   spring.cloud.gateway.routes[0].id=baidu
   spring.cloud.gateway.routes[0].uri=https://www.baidu.com/
   spring.cloud.gateway.routes[0].predicates[0]=Path=/baidu/**
   spring.cloud.gateway.routes[0].filters[0]=StripPrefix=1
   # 路由规则2
   spring.cloud.gateway.routes[1].id=jd
   spring.cloud.gateway.routes[1].uri=https://www.jd.com/
   spring.cloud.gateway.routes[1].predicates[0]=Path=/jd/**
   spring.cloud.gateway.routes[1].filters[0]=StripPrefix=1
   # 配置日志
   logging.level.org.springframework.cloud.gateway=trace
   logging.level.org.springframework.http.server.reactive=debug
   logging.level.org.springframework.web.reactive=debug
   logging.level.reactor.ipc.netty=debug
   # 配置actuator监控
   # 注意在properties中这里不能使用'*'，否则无法访问，yml中使用'*'
   management.endpoints.web.exposure.include=*
   management.endpoint.health.show-details=always
   

3. 启动服务查看路由规则

    http://localhost:8080/actuator/gateway/routes

服务发现的路由规则

1. 添加依赖

   <dependency>
       <groupId>org.springframework.cloud</groupId>
       <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
   </dependency>
   

2. 添加配置

   # 服务发现配置
   # 是否与服务发现组件结合，通过serviceId转发到具体的服务实例
   spring.cloud.gateway.discovery.locator.enabled=true
   # 服务名通过小写访问（默认大写）
   spring.cloud.gateway.discovery.locator.lower-case-service-id=true
   # 注册中心地址
   eureka.client.service-url.defaultZone=http://localhost:8686/eureka
   # 路由规则3
   spring.cloud.gateway.routes[2].id=client-a
   spring.cloud.gateway.routes[2].uri=lb://client-a
   spring.cloud.gateway.routes[2].predicates[0]=Path=/client-a/**
   spring.cloud.gateway.routes[2].filters[0]=RewritePath=/client-a/(?<segment>.*),/$\\{segment}
   

自定义Gateway Filter

1. 编写自定义filter业务实现

   @Slf4j
   public class CustomGatewayFilter implements GatewayFilter {
         
         
       private static final String COUNT_START_TIME = "COUNT_START_TIME" ;
       @Override
       public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
         
         
           exchange.getAttributes().put(COUNT_START_TIME, System.currentTimeMillis()) ;
           return chain.filter(exchange).then(
              Mono.fromRunnable(()->{
         
         
                  Long startTime = exchange.getAttribute(COUNT_START_TIME);
                  long endTime = (System.currentTimeMillis() - startTime) ;
                  log.info("=====> " + exchange.getRequest().getURI().getRawPath() +": " + endTime +"ms");
              })
           );
       }
   }
   

2. 将自定义filter加入到路由规则中 （Gateway不能直接URL重写）

   @Configuration
   public class MyConfig {
         
         
       @Bean
       public RouteLocator customerRouteLocator(RouteLocatorBuilder builder) {
         
         
           return builder.routes()
               .route(r -> r.path("/customer/**")
                       .filters(f -> f.stripPrefix(1).filter(new CustomGatewayFilter()))
                      // 注意这里写http://localhost:8081与写http://localhost:8081/hello效果一样
                       .uri("http://localhost:8081/hello")
                       .order(0)
                       .id("customer_filter_router")
               )
               .build();
       }
   }
   

自定义Global Filter

1. 编写自定义Filter业务实现

   @Component
   public class AuthSignatureFilter implements GlobalFilter, Ordered {
         
         
      @Override
      public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
         
         
          String token = exchange.getRequest().getQueryParams().getFirst("authToken") ;
          if (token == null || token.isEmpty()){
         
         
              // 当请求不携带token或则token为空时，直接设置请求状态码为401，返回
              exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED) ;
              return exchange.getResponse().setComplete() ;
          }
          return chain.filter(exchange);
      }
   
      @Override
      public int getOrder() {
         
         
          return -400;
      }
   }
   

2. Gateway Filter与Global Filter的区别

   从作用范围来看，Global Filter会被应用到所有的路由上，而Gateway Filter仅应用到单个路由或则一个分组路由上

权重路由