一、新建gateway项目

二、添加依赖

dependencies {
      implementation 'org.springframework.cloud:spring-cloud-starter-gateway:4.0.0'
}

三、增加路由规则配置

一个web服务、一个service服务

bootstrap.yaml：

server:
  port: 80
spring:
  application:
    name: gateway
  cloud:
    nacos:
      discovery:
        server-addr: ${NACOS_ADDR:127.0.0.1:8848}
        namespace: ${NACOS_NAMESPACE:demo}
        username: nacos
        password: nacos
      config:
        #nacos配置中心服务器地址
        server-addr: ${NACOS_ADDR:127.0.0.1:8848}
        #nacos配置中心命名空间
        namespace: ${NACOS_NAMESPACE:demo}
        #文件后缀格式
        file-extension: yaml
        #nacos配置中心分组
        group: ${spring.application.name}
        username: nacos
        password: nacos
        #扩展文件，目前用于全局共享，下面的优先级高
        ext-config:
          - data-id: commom.yaml
            group: common
            refresh: true

application.yaml：

spring:
  main:
    web-application-type: reactive
  cloud:
    gateway:
      routes:
        #业务服务
        - id: web_route
          uri: lb://web
          predicates:
            - Path=/web/**
          filters:
            - RewritePath=/(?<segment>.*),/$\{segment}
        #支撑服务
        - id: service_route
          uri: lb://service
          predicates:
            - Path=/service/**
          filters:
            - RewritePath=/(?<segment>.*),/$\{segment}

四、增加过滤器（可选）

比如认证、鉴权、日志打印等

例如：打印日志，用@Slf4j 注解来简化日志记录、

增加依赖

		compileOnly 'org.projectlombok:lombok:1.18.24' // 使用最新版本
		annotationProcessor 'org.projectlombok:lombok:1.18.24'
		implementation 'org.slf4j:slf4j-api:2.0.6'
		runtimeOnly 'ch.qos.logback:logback-classic:1.4.5'

代码：

@Slf4j
@Component
public class RequestLogFilter implements GlobalFilter, Ordered {

    private static final String START_TIME_KEY = "startTime";

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        ServerHttpRequest request = exchange.getRequest();
        String method = Objects.requireNonNull(request.getMethod()).name();

        String requestURI = request.getPath().toString();
        String remoteAddr = Objects.requireNonNull(request.getRemoteAddress()).getHostString();

        System.out.println("method=" + method +";requestURI= "+ requestURI+ "; remoteAddr="+remoteAddr);
        log.info("method=" + method +";requestURI= "+ requestURI+ "; remoteAddr="+remoteAddr);

        return chain.filter(exchange);
    }

    @Override
    public int getOrder() {
        return 1;
    }
}

五、增加启动类并运行测试

@SpringBootApplication(scanBasePackages = {"com.example"})
@EnableDiscoveryClient
public class GatewayApplication {

    public static void main(String[] args) {
        SpringApplication.run(GatewayApplication.class, args);
    }

}

运行访问，用80端口

六、遇到的问题

1、启动报错

缺少依赖的包

Error starting ApplicationContext. To display the condition evaluation report re-run your application with 'debug' enabled.
2024-07-16T16:27:44.792+08:00 ERROR 9924 --- [gateway] [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Web application could not be started as there was no org.springframework.boot.web.reactive.server.ReactiveWebServerFactory bean defined in the context.

Action:

Check your application's dependencies for a supported reactive web server.
Check the configured web application type.