前言
本文采用Spring cloud本文为2.1.8RELEASE,version=Greenwich.SR3
本文基于前两篇文章eureka-server、eureka-client、eureka-ribbon和eureka-feign的实现。
参考
概念
Spring Cloud Gateway是Spring Cloud的一个新项目,该项目是基于Spring5.0,Sprint Boot2.0和Project Reactor等技术开发的网关,它的目的是在微服务架构中提供一种简单有效的统一api路由管理方式。
Spring Cloud Gateway目标是要替代Netflix Zuul,其不仅提供统一的路由管理方式,还提供一套基于Fliter链的方式的网关其他功能,比如:限流、埋点、安全监控等。
名称术语
- Route(路由):网关的基本模块,它有一个id、一个目标uri、一组断言和一组过滤器组成,如果断言为真,则路由匹配。
- Predicate(断言):是一个java8的Predicate。输入类型是一个ServerWebExchange。可以使用它来匹配来自HTTP请求的内容。
- Filter(过滤器):是org.springframework.cloud.gateway.filter.GatewayFilter的实例,可以使用它来修改请求和响应。
流程
客户端向Spring Cloud Gateway发出请求。如果Gateway Handler映射确定请求与路由匹配,则将其发送到Gateway Web Handler。Gateway Web Handler通过特定于请求的筛选器链发送请求。筛选器由虚线分隔的原因是,筛选器可以在发送代理请求之前或之后执行逻辑。执行所有“pre”筛选逻辑,然后发出代理请求。在发出代理请求后,执行“POST”筛选逻辑。
创建Gateway工程
1.1 创建sping boot工程:spring-gateway
1.2 添加pom.xml相关依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
1.3 application.yml添加配置信息
server:
port: 8100
spring:
application:
name: spring-gateway
cloud:
gateway:
discovery:
locator:
enabled: true
eureka:
instance:
hostname: eureka1.server.com
lease-renewal-interval-in-seconds: 5
lease-expiration-duration-in-seconds: 10
client:
service-url:
defaultZone: http://eureka1.server.com:8701/eureka/,http://eureka2.server.com:8702/eureka/,http://eureka3.server.com:8703/eureka/
Spring.cloud.gateway.discovery.locator.enabled:true 这里先简单使用了默认的创建路由规则,自动根据serviceid创建路由的功能
1.4 启动类SpringGatewayApplication说明
前几篇文章中都在对应的启动类中增加了@EnableEurekaClient或@EnableDiscoveryClient注解,今天看文档突然发现,不用加@Enable*注解也可以自动添加到注册中心,是因为在Spring Cloud Edgware版本之后,只要加上相关的依赖,并进行相应的配置就可以将服务自动注册到服务发现组件上。
1.5 启动相关服务
按顺序启动eureka-server、eureka-client、eureka-ribbon、spring-gateway服务。
打开浏览器,先去eureka-server服务中心看一下服务是否正常启动,如下如:
截图中红框代表所有服务已经正常启动。
然后新打来浏览器输入:http://localhost:8100/SPRING-GATEWAY/EUREKA-RIBBON/sayHello,显示如下:
因为我们才用的是自动配置路由,所有这里url上的服务名称要全部大写,就是和服务注册中心保存一致。
这里我可以看一下spring-gate的启动日志,自动路由名称全部是大写。(个人觉得这里设计的不是很好)。
2019-10-12 16:40:35.870 INFO 97725 --- [ctor-http-nio-2] c.netflix.config.ChainedDynamicProperty : Flipping property: SPRING-GATEWAY.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647
2019-10-12 16:40:35.890 INFO 97725 --- [ctor-http-nio-2] c.n.u.concurrent.ShutdownEnabledTimer : Shutdown hook installed for: NFLoadBalancer-PingTimer-SPRING-GATEWAY
2019-10-12 16:40:35.890 INFO 97725 --- [ctor-http-nio-2] c.netflix.loadbalancer.BaseLoadBalancer : Client: SPRING-GATEWAY instantiated a LoadBalancer: DynamicServerListLoadBalancer:{NFLoadBalancer:name=SPRING-GATEWAY,current list of Servers=[],Load balancer stats=Zone stats: {},Server stats: []}ServerList:null
2019-10-12 16:40:35.895 INFO 97725 --- [ctor-http-nio-2] c.n.l.DynamicServerListLoadBalancer : Using serverListUpdater PollingServerListUpdater
2019-10-12 16:40:35.910 INFO 97725 --- [ctor-http-nio-2] c.netflix.config.ChainedDynamicProperty : Flipping property: SPRING-GATEWAY.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647
2019-10-12 16:40:35.911 INFO 97725 --- [ctor-http-nio-2] c.n.l.DynamicServerListLoadBalancer : DynamicServerListLoadBalancer for client SPRING-GATEWAY initialized: DynamicServerListLoadBalancer:{NFLoadBalancer:name=SPRING-GATEWAY,current list of Servers=[eureka1.server.com:8100],Load balancer stats=Zone stats: {defaultzone=[Zone:defaultzone; Instance count:1; Active connections count: 0; Circuit breaker tripped count: 0; Active connections per server: 0.0;]
},Server stats: [[Server:eureka1.server.com:8100; Zone:defaultZone; Total Requests:0; Successive connection failure:0; Total blackout seconds:0; Last connection made:Thu Jan 01 08:00:00 CST 1970; First connection made: Thu Jan 01 08:00:00 CST 1970; Active Connections:0; total failure count in last (1000) msecs:0; average resp time:0.0; 90 percentile resp time:0.0; 95 percentile resp time:0.0; min resp time:0.0; max resp time:0.0; stddev resp time:0.0]
]}ServerList:org.springframework.cloud.netflix.ribbon.eureka.DomainExtractingServerList@3b80e99c
2019-10-12 16:40:36.008 INFO 97725 --- [tor-http-nio-10] c.netflix.config.ChainedDynamicProperty : Flipping property: EUREKA-RIBBON.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647
2019-10-12 16:40:36.009 INFO 97725 --- [tor-http-nio-10] c.n.u.concurrent.ShutdownEnabledTimer : Shutdown hook installed for: NFLoadBalancer-PingTimer-EUREKA-RIBBON
2019-10-12 16:40:36.010 INFO 97725 --- [tor-http-nio-10] c.netflix.loadbalancer.BaseLoadBalancer : Client: EUREKA-RIBBON instantiated a LoadBalancer: DynamicServerListLoadBalancer:{NFLoadBalancer:name=EUREKA-RIBBON,current list of Servers=[],Load balancer stats=Zone stats: {},Server stats: []}ServerList:null
2019-10-12 16:40:36.011 INFO 97725 --- [tor-http-nio-10] c.n.l.DynamicServerListLoadBalancer : Using serverListUpdater PollingServerListUpdater
2019-10-12 16:40:36.012 INFO 97725 --- [tor-http-nio-10] c.netflix.config.ChainedDynamicProperty : Flipping property: EUREKA-RIBBON.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647
2019-10-12 16:40:36.012 INFO 97725 --- [tor-http-nio-10] c.n.l.DynamicServerListLoadBalancer : DynamicServerListLoadBalancer for client EUREKA-RIBBON initialized: DynamicServerListLoadBalancer:{NFLoadBalancer:name=EUREKA-RIBBON,current list of Servers=[eureka1.server.com:8901],Load balancer stats=Zone stats: {defaultzone=[Zone:defaultzone; Instance count:1; Active connections count: 0; Circuit breaker tripped count: 0; Active connections per server: 0.0;]
},Server stats: [[Server:eureka1.server.com:8901; Zone:defaultZone; Total Requests:0; Successive connection failure:0; Total blackout seconds:0; Last connection made:Thu Jan 01 08:00:00 CST 1970; First connection made: Thu Jan 01 08:00:00 CST 1970; Active Connections:0; total failure count in last (1000) msecs:0; average resp time:0.0; 90 percentile resp time:0.0; 95 percentile resp time:0.0; min resp time:0.0; max resp time:0.0; stddev resp time:0.0]
]}ServerList:org.springframework.cloud.netflix.ribbon.eureka.DomainExtractingServerList@19148ab
同样的方式我可以请求eureka-feign,结果如下:
至此基于服务发现的默认路由规则就搭建完成。
1.6 自定义路由规则
1.6.1 修改application.yml配置
server:
port: 8100
spring:
application:
name: spring-gateway
cloud:
gateway:
# discovery:
# locator:
# enabled: true # 开启通过服务中心的自动根据 serviceId 创建路由的功能
routes:
- id: ribbon-route
uri: lb://EUREKA-RIBBON
order: 0
predicates:
- Path=/ribbon/**
filters:
- StripPrefix=1 #去掉前缀,具体实现参考StripPrefixGatewayFilterFactory
- AddResponseHeader=X-Response-Default-Foo, Default-Bar
- id: feign-route
uri: lb://EUREKA-FEIGN
order: 0
predicates:
- Path=/feign/**
filters:
- StripPrefix=1
- AddResponseHeader=X-Response-Default-Foo, Default-Bar
eureka:
instance:
hostname: eureka1.server.com
lease-renewal-interval-in-seconds: 5
lease-expiration-duration-in-seconds: 10
client:
service-url:
defaultZone: http://eureka1.server.com:8701/eureka/,http://eureka2.server.com:8702/eureka/,http://eureka3.server.com:8703/eureka/
StripPrefix: 接受一个非负整数,对应的具体实现是StripPrefixGatewayFilterFactory,做用是去掉前缀,整数对应层数。在本例中访问的/ribbon/sayHello,网关服务向后转发请求的时候会去掉/ribbon,eureka-ribbon收到的请求是:/sayHello。eureka-feign同理。
1.6.2 启动服务
访问http://localhost:8100/ribbon/sayHello和http://localhost:8100/feign/feign/sayHello,如图下图显示:
- ribbon:
- feign:
1.6.3 自定义Configuration
Spring Cloud Gateway同时支持java的流式api的路由定义,可以和application.yml配合使用。
package spring.cloud.demo.spring.gateway.config;
import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.route.builder.RouteLocatorBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class RoutesConfig {
@Bean
public RouteLocator routeLocator(RouteLocatorBuilder routeLocatorBuilder){
return routeLocatorBuilder.routes().route(r -> r.path("/ribbon/**")
.filters(f -> f.stripPrefix(1)
.addRequestHeader("X-Response-Default-Foo", "Default-Bar"))
.uri("lb://EUREKA-RIBBON")
.order(0)
.id("ribbon-route")
).build();
}
}
总结
本文简单实现了Spring Cloud Gateway的默认自动路由和自定义路由的网关服务。后面会继续更新Spring Cloud Gateway的其他功能,敬请期待!
代码地址
- spring cloud 2.x版本 Eureka Server服务注册中心教程
- spring cloud 2.x版本 Eureka Client服务提供者教程
- spring cloud 2.x版本 Ribbon服务发现教程(内含集成Hystrix熔断机制)
- spring cloud 2.x版本 Feign服务发现教程(内含集成Hystrix熔断机制)
- spring cloud 2.x版本 Zuul路由网关教程
- spring cloud 2.x版本 config分布式配置中心教程
- spring cloud 2.x版本 Hystrix Dashboard断路器教程
- spring cloud 2.x版本 Gateway路由网关教程
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