Nacos服务注册与发现源码

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
  com.alibaba.cloud.nacos.discovery.NacosDiscoveryAutoConfiguration,\
  com.alibaba.cloud.nacos.endpoint.NacosDiscoveryEndpointAutoConfiguration,\
  com.alibaba.cloud.nacos.registry.NacosServiceRegistryAutoConfiguration,\
  com.alibaba.cloud.nacos.discovery.NacosDiscoveryClientConfiguration,\
  com.alibaba.cloud.nacos.discovery.reactive.NacosReactiveDiscoveryClientConfiguration,\
  com.alibaba.cloud.nacos.discovery.configclient.NacosConfigServerAutoConfiguration,\
  com.alibaba.cloud.nacos.NacosServiceAutoConfiguration
org.springframework.cloud.bootstrap.BootstrapConfiguration=\
  com.alibaba.cloud.nacos.discovery.configclient.NacosDiscoveryClientConfigServiceBootstrapConfiguration

@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.TYPE, ElementType.METHOD })
@ConditionalOnProperty(value = "spring.cloud.nacos.discovery.enabled",matchIfMissing = true)
public @interface ConditionalOnNacosDiscoveryEnabled {
}

public class NacosServiceRegistry implements ServiceRegistry<Registration> {
    private final NacosDiscoveryProperties nacosDiscoveryProperties;
    @Autowired
    private NacosServiceManager nacosServiceManager;
    
    //客户端往nacos注册中心进行服务注册
    @Override
    public void register(Registration registration) {
​
        if (StringUtils.isEmpty(registration.getServiceId())) {
            log.warn("No service to register for nacos client...");
            return;
        }
​
        NamingService namingService = namingService();
        String serviceId = registration.getServiceId();
        String group = nacosDiscoveryProperties.getGroup();
        //当前节点实例信息
        Instance instance = getNacosInstanceFromRegistration(registration);
        try {
            //通过beanReactor创建心跳检测任务(有一定配置,默认是true,创建临时节点,定时查询nacos,如果nacos上没找到就重新注册上去)
            //通过serverProxy往nacos客户端注册服务实例
            namingService.registerInstance(serviceId, group, instance);
        }
        catch (Exception e) {
            rethrowRuntimeException(e);
        }
    }
}

    private NamingService buildNamingService(Properties properties) {
        if (Objects.isNull(namingService)) {
            synchronized (NacosServiceManager.class) {
                if (Objects.isNull(namingService)) {
                    namingService = createNewNamingService(properties);
                }
            }
        }
        return namingService;
    }

public class HostReactor implements Closeable {
   private static final long DEFAULT_DELAY = 1000L;
    private static final long UPDATE_HOLD_INTERVAL = 5000L;
    private final Map<String, ScheduledFuture<?>> futureMap = new HashMap<String, ScheduledFuture<?>>();
    //服务的内存缓存
    private final Map<String, ServiceInfo> serviceInfoMap;
    //临时记录节点变更
    private final Map<String, Object> updatingMap;
    //本地启用一个udp端口,主动接受服务端的变更通知
    private final PushReceiver pushReceiver;
    //心跳检测 - 在这个类中创建心跳检测任务
    private final BeatReactor beatReactor;
    //nacos交互代理
    private final NamingProxy serverProxy;
    //failover-mode 模式下,使用本地文件代替内存缓存来返回服务信息
    private final FailoverReactor failoverReactor;
    //本地文件缓存的地址,默认 user.home\nacos\naming\namespace
    private final String cacheDir;
    private final boolean pushEmptyProtection;
    private final ScheduledExecutorService executor;
    //实例变更事件的订阅者
    private final InstancesChangeNotifier notifier;
    public HostReactor(NamingProxy serverProxy, BeatReactor beatReactor, String cacheDir, boolean loadCacheAtStart,
            boolean pushEmptyProtection, int pollingThreadCount) {
        // init executorService
        this.executor = new ScheduledThreadPoolExecutor(pollingThreadCount, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                thread.setName("com.alibaba.nacos.client.naming.updater");
                return thread;
            }
        });
        this.beatReactor = beatReactor;
        this.serverProxy = serverProxy;
        this.cacheDir = cacheDir;
        if (loadCacheAtStart) {
            this.serviceInfoMap = new ConcurrentHashMap<String, ServiceInfo>(DiskCache.read(this.cacheDir));
        } else {
            this.serviceInfoMap = new ConcurrentHashMap<String, ServiceInfo>(16);
        }
        this.pushEmptyProtection = pushEmptyProtection;
        this.updatingMap = new ConcurrentHashMap<String, Object>();
        this.failoverReactor = new FailoverReactor(this, cacheDir);
        this.pushReceiver = new PushReceiver(this);
        this.notifier = new InstancesChangeNotifier();
        
        //注册一个InstancesChangeEvent事件的发布器,将notifier作为订阅者
        NotifyCenter.registerToPublisher(InstancesChangeEvent.class, 16384);
        NotifyCenter.registerSubscriber(notifier);
    }
}

{"name":"DEFAULT_GROUP@@nacos-consumer","clusters":"DEFAULT","cacheMillis":10000,"hosts":[{"instanceId":"172.23.215.241#8090#DEFAULT#DEFAULT_GROUP@@nacos-consumer","ip":"172.23.215.241","port":8090,"weight":1.0,"healthy":true,"enabled":true,"ephemeral":true,"clusterName":"DEFAULT","serviceName":"DEFAULT_GROUP@@nacos-consumer","metadata":{"preserved.register.source":"SPRING_CLOUD"},"instanceHeartBeatInterval":5000,"instanceHeartBeatTimeOut":15000,"ipDeleteTimeout":30000}],"lastRefTime":1632383613389,"checksum":"","allIPs":false,"reachProtectionThreshold":false,"valid":true}