spring:
  application:
    name: item-order
  cloud:
    nacos:
      server-addr: 127.0.0.1:8848
      username: nacos
      password: nacos
      discovery:
        metadata:
          route.enable: true
          route.prefix: 1
          route.path: /order/**

import com.alibaba.cloud.nacos.discovery.NacosServiceDiscovery;
import com.alibaba.fastjson.JSON;
import com.alibaba.nacos.api.exception.NacosException;
import lombok.extern.slf4j.Slf4j;
import org.example.gateway.base.GatewayRouteDefinition;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.event.HeartbeatEvent;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.EventListener;
import java.util.List;
import java.util.Map;
import java.util.Objects;
/**
 * 自動(dòng)注冊(cè)網(wǎng)關(guān)路由配置
 * 通過注冊(cè)中心的心跳機(jī)制實(shí)時(shí)查詢是否注冊(cè)
 *
 * @author 苦瓜不苦
 * @date 2022/11/15 14:19
 **/
@Slf4j
@Configuration
public class RouteRegisterConfig {
    // nacos服務(wù)發(fā)現(xiàn)
    private final NacosServiceDiscovery nacosServiceDiscovery;
    // 自定義的ApplicationEventPublisherAware子類，里面實(shí)現(xiàn)了save()和delete()方法
    private final GatewayRouteConfig gatewayRouteConfig;
    public RouteRegisterConfig(NacosServiceDiscovery nacosServiceDiscovery, GatewayRouteConfig gatewayRouteConfig) {
        this.nacosServiceDiscovery = nacosServiceDiscovery;
        this.gatewayRouteConfig = gatewayRouteConfig;
    }
    // @EventListener事件監(jiān)聽注解，監(jiān)聽HeartbeatEvent心跳機(jī)制
    @EventListener(classes = HeartbeatEvent.class)
    public void eventListen(ApplicationEvent applicationEvent) {
        try {
            // 根據(jù)當(dāng)前服務(wù)分組查詢注冊(cè)的所有服務(wù)名
            List<String> serviceList = nacosServiceDiscovery.getServices();
            if (Objects.isNull(serviceList) || serviceList.size() <= 0) {
                return;
            }
            // 循環(huán)所有服務(wù)獲取服務(wù)信息
            for (String service : serviceList) {
                // 判斷是否注冊(cè)路由，MAP對(duì)象記錄的是配置成功的路由，通過服務(wù)ID來判斷唯一性
                if (gatewayRouteConfig.MAP.containsKey(service)) {
                    continue;
                }
                // 獲取當(dāng)前服務(wù)ID所有的節(jié)點(diǎn)
                List<ServiceInstance> instanceList = nacosServiceDiscovery.getInstances(service);
                if (Objects.isNull(instanceList) || instanceList.size() <= 0) {
                    continue;
                }
                // 獲取指定服務(wù)ID的第一個(gè)節(jié)點(diǎn)，是否需要遍歷所有，根據(jù)實(shí)際情況決定，因?yàn)闀?huì)存在一個(gè)微服務(wù)多實(shí)例節(jié)點(diǎn)
                ServiceInstance instance = instanceList.get(0);
                // 獲取當(dāng)前實(shí)例節(jié)點(diǎn)的元數(shù)據(jù)，主要是獲取到上面所配置的信息
                Map<String, String> metadata = instance.getMetadata();
                // 判斷是否開啟注冊(cè)路由
                if ("true".equals(metadata.get("route.enable"))) {
                    // 定制路由JSON模板
                    String template = "{\"filters\":[{\"name\":\"StripPrefix\",\"args\":{\"_genkey_0\":\"{StripPrefix}\"}}],\"id\":\"{id}\",\"uri\":\"lb://{id}\",\"order\":0,\"predicates\":[{\"name\":\"Path\",\"args\":{\"_genkey_0\":\"{Path}\"}}]}";
                    // 替換模板中的數(shù)據(jù)
                    template = template.replace("{id}", service)
                            .replace("{Path}", metadata.getOrDefault("route.path", "/**"))
                            .replace("{StripPrefix}", metadata.getOrDefault("route.prefix", "0"));
                    GatewayRouteDefinition definition = JSON.parseObject(template, GatewayRouteDefinition.class);
                    // 調(diào)用注冊(cè)路由方法
                    gatewayRouteConfig.save(definition);
                    log.info("服務(wù)節(jié)點(diǎn) {} 注冊(cè)路由成功, 路由信息 \n {}", service, JSON.toJSONString(definition));
                }
            }
        } catch (NacosException e) {
            log.error("注冊(cè)中心心跳機(jī)制監(jiān)聽失敗\n", e);
        }
    }
}