Spring Cloud Gateway 是 Spring Cloud 新推出的網關框架,之前是 Netflix Zuul。
網關通常在項目中爲了簡化前端的調用邏輯,同時也簡化內部服務之間互相調用的複雜度;
具體作用就是轉發服務,接收並轉發所有內外部的客戶端調用;
其他常見的功能還有權限認證,限流控制等等。
Spring Cloud Gateway使用的Webflux中的reactor-netty響應式編程組件,底層使用了Netty通訊框架
作用:
1.反向代理
2.鑑權
3.流量控制
4.熔斷
5.日誌監控
…
三大核心概念
- Route(路由)
路由是構建網關的基本模塊,它由ID,目標URI,一系列的斷言和過濾器組成,如果斷言爲true則匹配該路由 - Predicate(斷言)
參考的是java8的java.util.function.Predicate
開發人員可以匹配HTTP請求中的所有內容(例如請求頭或請求參數),如果請求與斷言相匹配則進行路由 - Filter(過濾)
指的是Spring框架中GatewayFilter的實例,使用過濾器,可以在請求被路由前或者之後對請求進行修改。
Gateway工作流程:路由轉發+執行過濾器鏈
入門配置
1.建module:gateway-gateway9527
2.pom
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>demo2020</artifactId>
<groupId>cn.chen.demo</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>gateway-gateway9527</artifactId>
<dependencies>
<!--新增gateway-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<!--公共模塊:通用工具包-->
<dependency>
<groupId>cn.chen.demo</groupId>
<artifactId>api-common</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
</project>
3.yml
server:
port: 9527
spring:
application:
name: cloud-gateway
cloud:
gateway:
routes:
- id: payment_routh #路由的ID,沒有固定規則但要求唯一,建議配合服務名
uri: http://localhost:8001 #匹配後提供服務的路由地址
predicates:
- Path=/payment/get/** #斷言,路徑相匹配的進行路由
- id: payment_routh2
uri: http://localhost:8001
predicates:
- Path=/payment/lb/** #斷言,路徑相匹配的進行路由
eureka:
instance:
hostname: cloud-gateway-service
client:
service-url:
register-with-eureka: true
fetch-registry: true
defaultZone: http://eureka7001.com:7001/eureka
4.主啓動
@SpringBootApplication
@EnableEurekaClient
public class GateWayApplication9527 {
public static void main(String[] args) {
SpringApplication.run(GateWayApplication9527.class,args);
}
}
5.業務類:無
6.測試
啓動eureka
啓動8001
啓動9527
訪問 http://localhost:8001/payment/get/1
訪問 http://localhost:9527/payment/get/1
Gateway網關路由有兩種配置方式
1.yml文件中配置 : 見上述demo
2.自己寫配置類: 代碼中注入RouteLocator的Bean
參考
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 GateWayConfig {
@Bean
public RouteLocator customRouteLocator(RouteLocatorBuilder routeLocatorBuilder) {
RouteLocatorBuilder.Builder routes = routeLocatorBuilder.routes();
routes.route("path_rote_atguigu", r -> r.path("/guonei").uri("http://news.baidu.com/guonei")).build();
return routes.build();
}
}
通過微服務名實現動態路由
默認情況下Gateway會根據註冊中心的服務列表,以註冊中心上微服務名爲路徑創建動態路由進行轉發,從而實現動態路由的功能
啓動:一個eureka7001+兩個服務提供者8001/8002
yml:
需要注意的是uri的協議爲lb,表示啓用Gateway的負載均衡功能。
lb://serviceName是spring cloud gateway在微服務中自動爲我們創建的負載均衡uri
yml修改:uri: lb://payment-service
Predicate的使用
- 常用的Route Predicate
Loaded RoutePredicateFactory [After]
Loaded RoutePredicateFactory [Before]
Loaded RoutePredicateFactory [Between]
Loaded RoutePredicateFactory [Cookie]
Loaded RoutePredicateFactory [Header]
Loaded RoutePredicateFactory [Host]
Loaded RoutePredicateFactory [Method]
Loaded RoutePredicateFactory [Path]
Loaded RoutePredicateFactory [Query]
Loaded RoutePredicateFactory [ReadBodyPredicateFactory]
Loaded RoutePredicateFactory [RemoteAddr]
Loaded RoutePredicateFactory [Weight]
Loaded RoutePredicateFactory [CloudFoundryRouteService]