Nacos - 客戶端心跳續約及客戶端總結

Nacos - 客戶端註冊中提到了心跳續約。

public void registerInstance(String serviceName, String groupName, Instance instance) throws NacosException {
    String groupedServiceName = NamingUtils.getGroupedName(serviceName, groupName);
    if (instance.isEphemeral()) {
        // 封裝心跳資訊
        BeatInfo beatInfo = beatReactor.buildBeatInfo(groupedServiceName, instance);
        // 開啟定時任務續約
        beatReactor.addBeatInfo(groupedServiceName, beatInfo);
    }
    serverProxy.registerService(groupedServiceName, groupName, instance);
}

BeatReactor#addBeatInfo

把心跳任務放入執行緒池。

public void addBeatInfo(String serviceName, BeatInfo beatInfo) {
    NAMING_LOGGER.info("[BEAT] adding beat: {} to beat map.", beatInfo);
    String key = buildKey(serviceName, beatInfo.getIp(), beatInfo.getPort());
    BeatInfo existBeat = null;
    //fix #1733
    // 移除舊的BeatInfo
    if ((existBeat = dom2Beat.remove(key)) != null) {
        existBeat.setStopped(true);
    }
    //存入dom2Beat
    dom2Beat.put(key, beatInfo);
    // 開啟定時任務
    executorService.schedule(new BeatTask(beatInfo), beatInfo.getPeriod(), TimeUnit.MILLISECONDS);
    MetricsMonitor.getDom2BeatSizeMonitor().set(dom2Beat.size());
}

BeatReactor.BeatTask#run

向伺服器傳送心跳，如果沒有心跳資訊，則重新註冊。

public void run() {
        if (beatInfo.isStopped()) {
            return;
        }
        long nextTime = beatInfo.getPeriod();
        try {
            // 向伺服器傳送心跳
            JsonNode result = serverProxy.sendBeat(beatInfo, BeatReactor.this.lightBeatEnabled);
            // 獲取下一次傳送的間隔時間
            long interval = result.get("clientBeatInterval").asLong();
            boolean lightBeatEnabled = false;
            if (result.has(CommonParams.LIGHT_BEAT_ENABLED)) {
                lightBeatEnabled = result.get(CommonParams.LIGHT_BEAT_ENABLED).asBoolean();
            }
            BeatReactor.this.lightBeatEnabled = lightBeatEnabled;
            if (interval > 0) {
                nextTime = interval;
            }
            int code = NamingResponseCode.OK;
            if (result.has(CommonParams.CODE)) {
                code = result.get(CommonParams.CODE).asInt();
            }
            // 發現沒有心跳資訊，則重新註冊
            if (code == NamingResponseCode.RESOURCE_NOT_FOUND) {
                Instance instance = new Instance();
                instance.setPort(beatInfo.getPort());
                instance.setIp(beatInfo.getIp());
                instance.setWeight(beatInfo.getWeight());
                instance.setMetadata(beatInfo.getMetadata());
                instance.setClusterName(beatInfo.getCluster());
                instance.setServiceName(beatInfo.getServiceName());
                instance.setInstanceId(instance.getInstanceId());
                instance.setEphemeral(true);
                try {
                    serverProxy.registerService(beatInfo.getServiceName(),
                            NamingUtils.getGroupName(beatInfo.getServiceName()), instance);
                } catch (Exception ignore) {
                }
            }
        } catch (NacosException ex) {
            NAMING_LOGGER.error("[CLIENT-BEAT] failed to send beat: {}, code: {}, msg: {}",
                    JacksonUtils.toJson(beatInfo), ex.getErrCode(), ex.getErrMsg());
            
        }
        executorService.schedule(new BeatTask(beatInfo), nextTime, TimeUnit.MILLISECONDS);
    }

客戶端總結