06、Sentinel实战：ClusterClientConfigManager-程序员江小北

    private static SentinelProperty<ClusterClientConfig> clientConfigProperty = new DynamicSentinelProperty<>();
    private static SentinelProperty<ClusterClientAssignConfig> clientAssignProperty = new DynamicSentinelProperty<>();
    private static final PropertyListener<ClusterClientConfig> CONFIG_PROPERTY_LISTENER
        = new ClientConfigPropertyListener();
    private static final PropertyListener<ClusterClientAssignConfig> ASSIGN_PROPERTY_LISTENER
        = new ClientAssignPropertyListener();

    private static final List<ServerChangeObserver> SERVER_CHANGE_OBSERVERS = new ArrayList<>();

    static {
        bindPropertyListener();
    }

    private static void bindPropertyListener() {
        removePropertyListener();
        clientAssignProperty.addListener(ASSIGN_PROPERTY_LISTENER);
        clientConfigProperty.addListener(CONFIG_PROPERTY_LISTENER);
    }

ClientConfigPropertyListener

主要监听请求超时时间的改变（sentinel后台管理并没有开放这个属性）

com.alibaba.csp.sentinel.cluster.client.config.ClusterClientConfigManager.ClientConfigPropertyListener#configLoad

        @Override
        public void configLoad(ClusterClientConfig config) {
            if (config == null) {
                RecordLog.warn("[ClusterClientConfigManager] Empty initial client config");
                return;
            }
            applyConfig(config);
        }

com.alibaba.csp.sentinel.cluster.client.config.ClusterClientConfigManager.ClientConfigPropertyListener#applyConfig

    private synchronized void applyConfig(ClusterClientConfig config) {
            if (!isValidClientConfig(config)) {
                RecordLog.warn(
                    "[ClusterClientConfigManager] Invalid cluster client config, ignoring: {}", config);
                return;
            }

            RecordLog.info("[ClusterClientConfigManager] Updating to new client config: {}", config);

            updateClientConfigChange(config);
        }
    }

    private static void updateClientConfigChange(ClusterClientConfig config) {
        if (config.getRequestTimeout() != requestTimeout) {
            requestTimeout = config.getRequestTimeout();
        }
    }

控制netty请求token时的超时时间

ClientAssignPropertyListener

主要监听token-client应该连接的token-server的ip和端口

        @Override
        public void configLoad(ClusterClientAssignConfig config) {
            if (config == null) {
                RecordLog.warn("[ClusterClientConfigManager] Empty initial client assignment config");
                return;
            }
            applyConfig(config);
        }

com.alibaba.csp.sentinel.cluster.client.config.ClusterClientConfigManager.ClientAssignPropertyListener#applyConfig

        private synchronized void applyConfig(ClusterClientAssignConfig config) {
            if (!isValidAssignConfig(config)) {
                RecordLog.warn(
                    "[ClusterClientConfigManager] Invalid cluster client assign config, ignoring: " + config);
                return;
            }
            if (serverPort == config.getServerPort() && config.getServerHost().equals(serverHost)) {
                return;
            }

            RecordLog.info("[ClusterClientConfigManager] Assign to new target token server: {}", config);

            updateServerAssignment(config);
        }

com.alibaba.csp.sentinel.cluster.client.config.ClusterClientConfigManager#updateServerAssignment

    private static void updateServerAssignment(/*@Valid*/ ClusterClientAssignConfig config) {
        String host = config.getServerHost();
        int port = config.getServerPort();

        for (ServerChangeObserver observer : SERVER_CHANGE_OBSERVERS) {
            observer.onRemoteServerChange(config);
        }

        serverHost = host;
        serverPort = port;
    }

com.alibaba.csp.sentinel.cluster.client.DefaultClusterTokenClient#changeServer

    private void changeServer(/*@Valid*/ ClusterClientAssignConfig config) {
        if (serverEqual(serverDescriptor, config)) {
            return;
        }
        try {
            //重启token-client客户端，连接新的token-server
            if (transportClient != null) {
                transportClient.stop();
            }
            // Replace with new, even if the new client is not ready.
            this.transportClient = new NettyTransportClient(config.getServerHost(), config.getServerPort());
            this.serverDescriptor = new TokenServerDescriptor(config.getServerHost(), config.getServerPort());
            startClientIfScheduled();
            RecordLog.info("[DefaultClusterTokenClient] New client created: {}", serverDescriptor);
        } catch (Exception ex) {
            RecordLog.warn("[DefaultClusterTokenClient] Failed to change remote token server", ex);
        }
    }