前言
本文采用Spring cloud本文為2.1.8RELEASE,version=Greenwich.SR3
本文基於前兩篇文章eureka-server、eureka-client、eureka-ribbon和eureka-feign的實現。
參考
概念
Spring Cloud Gateway是Spring Cloud的一個新項目,該項目是基於Spring5.0,Sprint Boot2.0和Project Reactor等技術開發的網關,它的目的是在微服務架構中提供一種簡單有效的統一api路由管理方式。
Spring Cloud Gateway目標是要替代Netflix Zuul,其不僅提供統一的路由管理方式,還提供一套基於Fliter鏈的方式的網關其他功能,比如:限流、埋點、安全監控等。
名稱術語
- Route(路由):網關的基本模塊,它有一個id、一個目標uri、一組斷言和一組過濾器組成,如果斷言為真,則路由匹配。
- Predicate(斷言):是一個java8的Predicate。輸入類型是一個ServerWebExchange。可以使用它來匹配來自HTTP請求的內容。
- Filter(過濾器):是org.springframework.cloud.gateway.filter.GatewayFilter的實例,可以使用它來修改請求和響應。
流程
客戶端向Spring Cloud Gateway發出請求。如果Gateway Handler映射確定請求與路由匹配,則將其發送到Gateway Web Handler。Gateway Web Handler通過特定於請求的篩選器鏈發送請求。篩選器由虛線分隔的原因是,篩選器可以在發送代理請求之前或之后執行邏輯。執行所有“pre”篩選邏輯,然后發出代理請求。在發出代理請求后,執行“POST”篩選邏輯。
創建Gateway工程
1.1 創建sping boot工程:spring-gateway
1.2 添加pom.xml相關依賴
<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 這里先簡單使用了默認的創建路由規則,自動根據serviceid創建路由的功能
1.4 啟動類SpringGatewayApplication說明
前幾篇文章中都在對應的啟動類中增加了@EnableEurekaClient或@EnableDiscoveryClient注解,今天看文檔突然發現,不用加@Enable*注解也可以自動添加到注冊中心,是因為在Spring Cloud Edgware版本之后,只要加上相關的依賴,並進行相應的配置就可以將服務自動注冊到服務發現組件上。
1.5 啟動相關服務
按順序啟動eureka-server、eureka-client、eureka-ribbon、spring-gateway服務。
打開瀏覽器,先去eureka-server服務中心看一下服務是否正常啟動,如下如:
截圖中紅框代表所有服務已經正常啟動。
然后新打來瀏覽器輸入:http://localhost:8100/SPRING-GATEWAY/EUREKA-RIBBON/sayHello,顯示如下:
因為我們才用的是自動配置路由,所有這里url上的服務名稱要全部大寫,就是和服務注冊中心保存一致。
這里我可以看一下spring-gate的啟動日志,自動路由名稱全部是大寫。(個人覺得這里設計的不是很好)。
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
同樣的方式我可以請求eureka-feign,結果如下:
至此基於服務發現的默認路由規則就搭建完成。
1.6 自定義路由規則
1.6.1 修改application.yml配置
server:
port: 8100
spring:
application:
name: spring-gateway
cloud:
gateway:
# discovery:
# locator:
# enabled: true # 開啟通過服務中心的自動根據 serviceId 創建路由的功能
routes:
- id: ribbon-route
uri: lb://EUREKA-RIBBON
order: 0
predicates:
- Path=/ribbon/**
filters:
- StripPrefix=1 #去掉前綴,具體實現參考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: 接受一個非負整數,對應的具體實現是StripPrefixGatewayFilterFactory,做用是去掉前綴,整數對應層數。在本例中訪問的/ribbon/sayHello,網關服務向后轉發請求的時候會去掉/ribbon,eureka-ribbon收到的請求是:/sayHello。eureka-feign同理。
1.6.2 啟動服務
訪問http://localhost:8100/ribbon/sayHello和http://localhost:8100/feign/feign/sayHello,如圖下圖顯示:
- ribbon:
- feign:
1.6.3 自定義Configuration
Spring Cloud Gateway同時支持java的流式api的路由定義,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();
}
}
總結
本文簡單實現了Spring Cloud Gateway的默認自動路由和自定義路由的網關服務。后面會繼續更新Spring Cloud Gateway的其他功能,敬請期待!
代碼地址
- spring cloud 2.x版本 Eureka Server服務注冊中心教程
- spring cloud 2.x版本 Eureka Client服務提供者教程
- spring cloud 2.x版本 Ribbon服務發現教程(內含集成Hystrix熔斷機制)
- spring cloud 2.x版本 Feign服務發現教程(內含集成Hystrix熔斷機制)
- spring cloud 2.x版本 Zuul路由網關教程
- spring cloud 2.x版本 config分布式配置中心教程
- spring cloud 2.x版本 Hystrix Dashboard斷路器教程
- spring cloud 2.x版本 Gateway路由網關教程
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