參考文檔：Spring Gateway官方文檔 , 玹霖的博客

1.Spring Gateway簡介

Spring Cloud Gateway是Spring官方基于Spring 5.0，Spring Boot 2.0和Project Reactor等技術開發(fā)的網(wǎng)關，Spring Cloud Gateway旨在為微服務架構提供一種簡單而有效的統(tǒng)一的API路由管理方式。Spring Cloud Gateway作為Spring Cloud生態(tài)系中的網(wǎng)關，目標是替代Netflix ZUUL，其不僅提供統(tǒng)一的路由方式，并且基于Filter鏈的方式提供了網(wǎng)關基本的功能，例如：安全，監(jiān)控/埋點，和限流等。

2.Spring Gateway工作原理

Spring Gateway工作結構圖

spring_cloud_gateway_diagram.png

3.Spring Gateway配置和使用

由于項目使用maven模塊化配置，Springboot版本為：2.0.3.RELEASE, SpringCloud版本為：Finchley.RELEASE

• pom配置：

<dependencies>
      <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <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-hystrix</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-contract-stub-runner</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-web</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-web</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

請注意：不要引入spring-boot-starter-web包，會導致Gateway啟動拋出異常

Spring Gateway支持兩種方式提供路由服務，其一是配置文件啟用，其二則是通過代碼達到目的

• application.yml配置實現(xiàn)

spring:
  application:
    name: xxxx
  cloud:
    consul:
      host: localhost
      port: 8500
      discovery:
        enabled: true
        instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${server.port}
        service-name: xxxx
        prefer-ip-address: true
    gateway:
      discovery:
        locator:
          enabled: true
      routes:
      # This route rule used to forward request to activity server
      - id: activity-route
        uri: lb://activity
        predicates:
        - Path=/activity/**
        filters:
        - StripPrefix=1

注意：Gateway默認轉(zhuǎn)發(fā)是全路徑的，設置StripPrefix=1表示從二級url路徑轉(zhuǎn)發(fā)，即http://localhost:port/activity/test將會轉(zhuǎn)發(fā)到http://{activity}/test

• 代碼實現(xiàn)

@Bean
public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
        return builder.routes()
                .route(r -> r.path("/activity/**")
                        .filters(f -> f.stripPrefix(1).filter(new TestGetWayFilter()).addResponseHeader("X-Response-Default-Foo", "Default-Bar"))
                        .uri("lb://activity")
                        .order(0)
                        .id("activity-route")
                )
                .build();
 }