Talk about Deregister Instance of Nacos Naming Service

order

This paper mainly studies the deregister Instance of Nacos Naming Service.

NacosNamingService

nacos-1.1.3/client/src/main/java/com/alibaba/nacos/client/naming/NacosNamingService.java

public class NacosNamingService implements NamingService {
    private static final String DEFAULT_PORT = "8080";
    private static final long DEFAULT_HEART_BEAT_INTERVAL = TimeUnit.SECONDS.toMillis(5);

    /**
     * Each Naming instance should have different namespace.
     */
    private String namespace;

    private String endpoint;

    private String serverList;

    private String cacheDir;

    private String logName;

    private HostReactor hostReactor;

    private BeatReactor beatReactor;

    private EventDispatcher eventDispatcher;

    private NamingProxy serverProxy;

    //......

    @Override
    public void deregisterInstance(String serviceName, String ip, int port) throws NacosException {
        deregisterInstance(serviceName, ip, port, Constants.DEFAULT_CLUSTER_NAME);
    }

    @Override
    public void deregisterInstance(String serviceName, String groupName, String ip, int port) throws NacosException {
        deregisterInstance(serviceName, groupName, ip, port, Constants.DEFAULT_CLUSTER_NAME);
    }

    @Override
    public void deregisterInstance(String serviceName, String ip, int port, String clusterName) throws NacosException {
        deregisterInstance(serviceName, Constants.DEFAULT_GROUP, ip, port, clusterName);
    }

    @Override
    public void deregisterInstance(String serviceName, String groupName, String ip, int port, String clusterName) throws NacosException {
        Instance instance = new Instance();
        instance.setIp(ip);
        instance.setPort(port);
        instance.setClusterName(clusterName);

        deregisterInstance(serviceName, groupName, instance);
    }

    @Override
    public void deregisterInstance(String serviceName, Instance instance) throws NacosException {
        deregisterInstance(serviceName, Constants.DEFAULT_GROUP, instance);
    }

    @Override
    public void deregisterInstance(String serviceName, String groupName, Instance instance) throws NacosException {
        if (instance.isEphemeral()) {
            beatReactor.removeBeatInfo(NamingUtils.getGroupedName(serviceName, groupName), instance.getIp(), instance.getPort());
        }
        serverProxy.deregisterService(NamingUtils.getGroupedName(serviceName, groupName), instance);
    }

    //......
}
  • The deregisterInstance method removes BeatInfo from beatReactor for instance of ephemeral (default is ephemeral) and then logs out the service through serverProxy.deregisterService.

BeatReactor

nacos-1.1.3/client/src/main/java/com/alibaba/nacos/client/naming/beat/BeatReactor.java

public class BeatReactor {

    private ScheduledExecutorService executorService;

    private NamingProxy serverProxy;

    public final Map<String, BeatInfo> dom2Beat = new ConcurrentHashMap<String, BeatInfo>();

    //......

    public void removeBeatInfo(String serviceName, String ip, int port) {
        NAMING_LOGGER.info("[BEAT] removing beat: {}:{}:{} from beat map.", serviceName, ip, port);
        BeatInfo beatInfo = dom2Beat.remove(buildKey(serviceName, ip, port));
        if (beatInfo == null) {
            return;
        }
        beatInfo.setStopped(true);
        MetricsMonitor.getDom2BeatSizeMonitor().set(dom2Beat.size());
    }

    //......

    class BeatTask implements Runnable {

        BeatInfo beatInfo;

        public BeatTask(BeatInfo beatInfo) {
            this.beatInfo = beatInfo;
        }

        @Override
        public void run() {
            if (beatInfo.isStopped()) {
                return;
            }
            long result = serverProxy.sendBeat(beatInfo);
            long nextTime = result > 0 ? result : beatInfo.getPeriod();
            executorService.schedule(new BeatTask(beatInfo), nextTime, TimeUnit.MILLISECONDS);
        }
    }

    //......
}
  • The removeBeatInfo method removes the specified key from the dom2Beat and marks its stopped as true; BeatTask first determines whether it is stopped or not, then sends heartbeat information through serverProxy.sendBeat, calculates the next scheduling time, and adds scheduling tasks to the executorService.

NamingProxy

nacos-1.1.3/client/src/main/java/com/alibaba/nacos/client/naming/net/NamingProxy.java

public class NamingProxy {

    private static final int DEFAULT_SERVER_PORT = 8848;

    private int serverPort = DEFAULT_SERVER_PORT;

    private String namespaceId;

    private String endpoint;

    private String nacosDomain;

    private List<String> serverList;

    private List<String> serversFromEndpoint = new ArrayList<String>();

    private long lastSrvRefTime = 0L;

    private long vipSrvRefInterMillis = TimeUnit.SECONDS.toMillis(30);

    private Properties properties;

    //......

    public void deregisterService(String serviceName, Instance instance) throws NacosException {

        NAMING_LOGGER.info("[DEREGISTER-SERVICE] {} deregistering service {} with instance: {}",
            namespaceId, serviceName, instance);

        final Map<String, String> params = new HashMap<String, String>(8);
        params.put(CommonParams.NAMESPACE_ID, namespaceId);
        params.put(CommonParams.SERVICE_NAME, serviceName);
        params.put(CommonParams.CLUSTER_NAME, instance.getClusterName());
        params.put("ip", instance.getIp());
        params.put("port", String.valueOf(instance.getPort()));
        params.put("ephemeral", String.valueOf(instance.isEphemeral()));

        reqAPI(UtilAndComs.NACOS_URL_INSTANCE, params, HttpMethod.DELETE);
    }

    //......
}
  • The deregisterService method of NamingProxy sends a DELETE request to the / instance interface for service logout.

Summary

The deregister Instance method of NacosNamingService removes BeatInfo from beatReactor for instance of ephemeral (default is ephemeral), and then logs out the service through server Proxy. deregisterService.

doc

Tags: Programming Java

Posted on Tue, 08 Oct 2019 03:21:43 -0700 by Frozenlight777