@CanDistro
@PutMapping("/beat")
@Secured(parser = NamingResourceParser.class, action = ActionTypes.WRITE)
public ObjectNode beat(HttpServletRequest request) throws Exception {
// 创建一个JSON Node，该方法的返回值就是它，后面的代码就是对这个Node进行各种初始化
ObjectNode result = JacksonUtils.createEmptyJsonNode();
result.put(SwitchEntry.CLIENT_BEAT_INTERVAL, switchDomain.getClientBeatInterval());
// 从请求中获取到beat，即client端的beatInfo
String beat = WebUtils.optional(request, "beat", StringUtils.EMPTY);
RsInfo clientBeat = null;
// 将beat构建为clientBeat
if (StringUtils.isNotBlank(beat)) {
clientBeat = JacksonUtils.toObj(beat, RsInfo.class);
}
String clusterName = WebUtils
.optional(request, CommonParams.CLUSTER_NAME, UtilsAndCommons.DEFAULT_CLUSTER_NAME);
String ip = WebUtils.optional(request, "ip", StringUtils.EMPTY);
// 获取到客户端传递来的client的port，其将来用于UDP通信
int port = Integer.parseInt(WebUtils.optional(request, "port", "0"));
if (clientBeat != null) {
if (StringUtils.isNotBlank(clientBeat.getCluster())) {
clusterName = clientBeat.getCluster();
} else {
// fix #2533
clientBeat.setCluster(clusterName);
}
ip = clientBeat.getIp();
port = clientBeat.getPort();
}
String namespaceId = WebUtils.optional(request, CommonParams.NAMESPACE_ID, Constants.DEFAULT_NAMESPACE_ID);
String serviceName = WebUtils.required(request, CommonParams.SERVICE_NAME);
checkServiceNameFormat(serviceName);
Loggers.SRV_LOG.debug("[CLIENT-BEAT] full arguments: beat: {}, serviceName: {}", clientBeat, serviceName);
// 从注册表中获取当前发送请求的client对应的instance,Ip port对应
Instance instance = serviceManager.getInstance(namespaceId, serviceName, clusterName, ip, port);
// 处理注册表中不存在该client的instance的情况
if (instance == null) {
// 若请求中没有携带心跳数据，则直接返回
if (clientBeat == null) {
result.put(CommonParams.CODE, NamingResponseCode.RESOURCE_NOT_FOUND);
return result;
}
Loggers.SRV_LOG.warn("[CLIENT-BEAT] The instance has been removed for health mechanism, "
+ "perform data compensation operations, beat: {}, serviceName: {}", clientBeat, serviceName);
// 下面处理的情况是，注册表中没有该client的instance，但其发送的请求中具有心跳数据。
// 在client的注册请求还未到达时（网络抖动等原因），第一次心跳请求先到达了server，会出现这种情况
// 处理方式是，使用心跳数据构建出一个instance，注册到注册表
instance = new Instance();
instance.setPort(clientBeat.getPort());
instance.setIp(clientBeat.getIp());
instance.setWeight(clientBeat.getWeight());
instance.setMetadata(clientBeat.getMetadata());
instance.setClusterName(clusterName);
instance.setServiceName(serviceName);
instance.setInstanceId(instance.getInstanceId());
instance.setEphemeral(clientBeat.isEphemeral());
// 注册
serviceManager.registerInstance(namespaceId, serviceName, instance);
}
// 从注册表中获取service
Service service = serviceManager.getService(namespaceId, serviceName);
if (service == null) {
throw new NacosException(NacosException.SERVER_ERROR,
"service not found: " + serviceName + "@" + namespaceId);
}
// 从请求中获取到beat为null
if (clientBeat == null) {
clientBeat = new RsInfo();
clientBeat.setIp(ip);
clientBeat.setPort(port);
clientBeat.setCluster(clusterName);
}
// 处理本次心跳
service.processClientBeat(clientBeat);
result.put(CommonParams.CODE, NamingResponseCode.OK);
if (instance.containsMetadata(PreservedMetadataKeys.HEART_BEAT_INTERVAL)) {
result.put(SwitchEntry.CLIENT_BEAT_INTERVAL, instance.getInstanceHeartBeatInterval());
}
result.put(SwitchEntry.LIGHT_BEAT_ENABLED, switchDomain.isLightBeatEnabled());
return result;
}
