【九月打卡】第14天 集成Alibaba Nacos实现动态路由配置

课程名称：Spring Cloud / Alibaba 微服务架构实战

课程章节：第7章-SpringCloud Gateway微服务

课程讲师：张勤一

课程内容：

• 7-4 集成 Alibaba Nacos 实现动态路由配置_慕课网 (imooc.com)

1.集成Alibaba Nacos实现动态路由配置

1.1 静态路由配置与动态路由配置

• 动态路由配置

  静态路由配置写在配置文件，端点是：spring.cloud.gateway

  gateway:
  routers:

  • id: path_route
    uri: ip:port/xxx/xx
    predicates:
  • Path: /xxx/{xx}

  缺点是每次改动都需要网关模块重新部署。

• 动态路由配置

  路由信息在Alibaba Nacos 中维护，可以实现动态变更。

package com.imooc.ecommerce.config;


import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;

/**
 * 读取 Nacos 相关的配置项，用于配置监听器
 */
@Configuration
public class GatewayConfig {

    /** 读取配置的超时时间*/
    public static final long DEFAULT_TIMEOUT = 30000;
    /** Nacos 服务器地址*/
    public static String NACOS_SERVER_ADDR;
    /** 命名空间*/
    public static String NACOS_NAMESPACE;
    /** data-id */
    public static String NACOS_ROUTE_DATA_ID;
    /** 分组id */
    public static String NACOS_ROUTE_GROUP;

    @Value("${spring.cloud.nacos.discover.server-addr}")
    public void setNacosServerAddr(String nacosServerAddr) {
        NACOS_SERVER_ADDR = nacosServerAddr;
    }

    @Value("${spring.cloud.nacos.discover.namespace}")
    public void setNacosNamespace(String nacosNamespace){
        NACOS_NAMESPACE = nacosNamespace;
    }

    @Value("${nacos.gateway.route.config.data-id}")
    public void setNacosRouteDataId(String nacosRouteDataId){
        NACOS_ROUTE_DATA_ID = nacosRouteDataId;
    }

    @Value("${nacos.gateway.route.config.group}")
    public void setNacosRouteGroup(String nacosRouteGroup){
        NACOS_ROUTE_GROUP = nacosRouteGroup;
    }
}

package com.imooc.ecommerce.config;

import com.alibaba.nacos.client.naming.utils.CollectionUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.event.RefreshRoutesEvent;
import org.springframework.cloud.gateway.route.RouteDefinition;
import org.springframework.cloud.gateway.route.RouteDefinitionLocator;
import org.springframework.cloud.gateway.route.RouteDefinitionWriter;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationEventPublisherAware;
import org.springframework.stereotype.Service;
import reactor.core.publisher.Mono;

import java.util.List;

@Slf4j
@Service
public class DynamicRouteServiceImpl implements ApplicationEventPublisherAware {

    /** 写路由定义 */
    private final RouteDefinitionWriter routeDefinitionWriter;

    /** 获取路由定义 */
    private final RouteDefinitionLocator routeDefinitionLocator;

    /** 事件发布 */
    private ApplicationEventPublisher publisher;

    public DynamicRouteServiceImpl(RouteDefinitionWriter routeDefinitionWriter, RouteDefinitionLocator routeDefinitionLocator){
        this.routeDefinitionWriter = routeDefinitionWriter;
        this.routeDefinitionLocator = routeDefinitionLocator;
    }
    @Override
    public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
        //完成事件推送句柄的初始化
        this.publisher = applicationEventPublisher;
    }

    /**
     * 增加路由定义
     * @param definition
     * @return
     */
    public String addRouteDefinition(RouteDefinition definition){
        log.info("gateway add route: [{}]", definition);

        //保存路由配置并发布
        routeDefinitionWriter.save(Mono.just(definition)).subscribe();
        //发布事件通知Gateway, 同步新增的路由定义
        this.publisher.publishEvent(new RefreshRoutesEvent(this));

        return "success";
    }

    /**
     * 更新路由
     */
    public String updateList(List<RouteDefinition> definitions){
        log.info("gateway update route: [{}]", definitions);
        //先拿到当前 Gateway中存储的路由定义
        List<RouteDefinition> routeDefinitionsExits = routeDefinitionLocator.getRouteDefinitions().buffer().blockFirst();
        if (!CollectionUtils.isEmpty(routeDefinitionsExits)){
            //清楚掉之前所有旧的路由定义
            routeDefinitionsExits.forEach(route -> {
                log.info("delete route definition: [{}]", route);
                deleteById(route.getId());
            });
        }
        //把更新的路由定义同步到 gateway 中
        definitions.forEach(definition -> {updateByRouteDefinition(definition);});
        return "success";
    }

    /**
     * 根据路由id删除路由配置
     * @param id
     * @return
     */
    private String deleteById(String id) {
        try {
            log.info("gateway delete route id: [{}]", id);
            this.routeDefinitionWriter.delete(Mono.just(id)).subscribe();
            return "delete success";
        } catch (Exception ex) {
            log.error("gateway delete route fail: [{}]", ex.getMessage(), ex);
            return "delete fail";
        }
    }

    /**
     * 更新路由
     * 删除 + 新增 = 更新
     */
    private String updateByRouteDefinition(RouteDefinition definition) {
        try {
            log.info("gateway update route: [{}]", definition);
            this.routeDefinitionWriter.delete(Mono.just(definition.getId()));
        } catch(Exception ex){
            log.error("update fail, not find route routeId:" + definition.getId());
            return "update fail";
        }

        try {
            this.routeDefinitionWriter.save(Mono.just(definition)).subscribe();
            this.publisher.publishEvent(new RefreshRoutesEvent(this));
            return "success";
        } catch(Exception ex) {
            log.error("update fail, not find route routeId:" + definition.getId());
            return "update fail";
        }
    }
}

课程截图：661词