spring cloud nacos源码解析（2）实例注册的那些事

//客户端注册请求
    @CanDistro
    @PostMapping
    @Secured(parser = NamingResourceParser.class, action = ActionTypes.WRITE)
    public String register(HttpServletRequest request) throws Exception {
        //获取命名空间 key = namespaceId  默认值public
        final String namespaceId = WebUtils
                .optional(request, CommonParams.NAMESPACE_ID, Constants.DEFAULT_NAMESPACE_ID);
        final String serviceName = WebUtils.required(request, CommonParams.SERVICE_NAME);
        NamingUtils.checkServiceNameFormat(serviceName);
        
        final Instance instance = parseInstance(request);
          //兼容版本 2.0.0版本 使用instanceServiceV2
        getInstanceOperator().registerInstance(namespaceId, serviceName, instance);
        return "ok";

    public static String optional(final HttpServletRequest req, final String key, final String defaultValue) {
// 获取key 没有则返回默认值
        if (!req.getParameterMap().containsKey(key) || req.getParameterMap().get(key)[0] == null) {
            return defaultValue;
        }
        String value = req.getParameter(key);
        if (StringUtils.isBlank(value)) {
            return defaultValue;
        }
//参数编码格式 默认utf-8
        String encoding = req.getParameter(ENCODING_KEY);
        return resolveValue(value, encoding);
    }


// 获取参数报告     
    public static String required(final HttpServletRequest req, final String key) {
        String value = req.getParameter(key);
//参数为空异异常
        if (StringUtils.isEmpty(value)) {
            throw new IllegalArgumentException("Param '" + key + "' is required.");
        }
        String encoding = req.getParameter(ENCODING_KEY);
        return resolveValue(value, encoding);
    }

    /**
     * check combineServiceName format. the serviceName can't be blank.
     * <pre>
     * serviceName = "@@";                 the length = 0; illegal
     * serviceName = "[email protected]@";            the length = 1; illegal
     * serviceName = "@@serviceName";      the length = 2; illegal
     * serviceName = "[email protected]@serviceName"; the length = 2; legal 分组@@服务名合法
     * </pre>
     *
     * @param combineServiceName such as: [email protected]@serviceName
     */
    public static void checkServiceNameFormat(String combineServiceName) {
        String[] split = combineServiceName.split(Constants.SERVICE_INFO_SPLITER);
        if (split.length <= 1) {
            throw new IllegalArgumentException(
                    "Param 'serviceName' is illegal, it should be format as '[email protected]@serviceName'");
        }
        if (split[0].isEmpty()) {
            throw new IllegalArgumentException("Param 'serviceName' is illegal, groupName can't be empty");
        }
    }

初始化实例

    private Instance getIpAddress(HttpServletRequest request) {
        
        String enabledString = WebUtils.optional(request, "enabled", StringUtils.EMPTY);
        boolean enabled;
        //是否启用
        if (StringUtils.isBlank(enabledString)) {
            enabled = BooleanUtils.toBoolean(WebUtils.optional(request, "enable", "true"));
        } else {
            enabled = BooleanUtils.toBoolean(enabledString);
        }
        //获取权重
        String weight = WebUtils.optional(request, "weight", "1");
        //是否健康
        boolean healthy = BooleanUtils.toBoolean(WebUtils.optional(request, "healthy", "true"));
        //获取基础实例
        Instance instance = getBasicIpAddress(request);
        instance.setWeight(Double.parseDouble(weight));
        instance.setHealthy(healthy);
        instance.setEnabled(enabled);
        
        return instance;
    }

    private Instance getBasicIpAddress(HttpServletRequest request) {
        //获取ip port
        final String ip = WebUtils.required(request, "ip");
        final String port = WebUtils.required(request, "port");
        //客户名称  clusterName
        String cluster = WebUtils.optional(request, CommonParams.CLUSTER_NAME, StringUtils.EMPTY);
        if (StringUtils.isBlank(cluster)) {
            //名称为空则获取cluster 没有则为default
            cluster = WebUtils.optional(request, "cluster", UtilsAndCommons.DEFAULT_CLUSTER_NAME);
        }
        boolean ephemeral = BooleanUtils.toBoolean(
                WebUtils.optional(request, "ephemeral", String.valueOf(switchDomain.isDefaultInstanceEphemeral())));
        
        Instance instance = new Instance();
        instance.setPort(Integer.parseInt(port));
        instance.setIp(ip);
        instance.setEphemeral(ephemeral);
        instance.setClusterName(cluster);
        
        return instance;
    }

建立service(实例处理对象)

    /**
     * Register an instance to a service in AP mode.
     *
     * <p>This method creates service or cluster silently if they don't exist.
     *
     * @param namespaceId id of namespace
     * @param serviceName service name
     * @param instance    instance to register
     * @throws Exception any error occurred in the process
     */
    public void registerInstance(String namespaceId, String serviceName, Instance instance) throws NacosException {

        // 不存在则创建 instance.isEphemeral()是否为临时 service true是 false不是
        createEmptyService(namespaceId, serviceName, instance.isEphemeral());
        //获取服务消息
        Service service = getService(namespaceId, serviceName);
        //service 为空 创建异常
        checkServiceIsNull(service, namespaceId, serviceName);
        //实例存放 在服务中
        addInstance(namespaceId, serviceName, instance.isEphemeral(), instance);
    }


    /**
     * Create service if not exist.
     *
     * @param namespaceId namespace
     * @param serviceName service name
     * @param local       whether create service by local
     * @param cluster     cluster
     * @throws NacosException nacos exception
     */
    public void createServiceIfAbsent(String namespaceId, String serviceName, boolean local, Cluster cluster)
            throws NacosException {
        Service service = getService(namespaceId, serviceName);
        if (service == null) {
            
            Loggers.SRV_LOG.info("creating empty service {}:{}", namespaceId, serviceName);
            service = new Service();
            service.setName(serviceName);
            service.setNamespaceId(namespaceId);
            service.setGroupName(NamingUtils.getGroupName(serviceName));
            // now validate the service. if failed, exception will be thrown
            service.setLastModifiedMillis(System.currentTimeMillis());
            //重新计算checkSum
            service.recalculateChecksum();
            if (cluster != null) {
                cluster.setService(service);
                service.getClusterMap().put(cluster.getName(), cluster);
            }
            service.validate();
            //存储初始化 初始化 创建健康检测定时任务
            putServiceAndInit(service);

            if (!local) {
 //不是临时service 处理则持久化消息
                addOrReplaceService(service);
            }
        }
    }

// 更新service 实例化信息
public List<Instance> updateIpAddresses(Service service, String action, boolean ephemeral, Instance... ips)
            throws NacosException {
        
        Datum datum = consistencyService
                .get(KeyBuilder.buildInstanceListKey(service.getNamespaceId(), service.getName(), ephemeral));
        
        List<Instance> currentIPs = service.allIPs(ephemeral);
        Map<String, Instance> currentInstances = new HashMap<>(currentIPs.size());
        Set<String> currentInstanceIds = Sets.newHashSet();
        
        for (Instance instance : currentIPs) {
            currentInstances.put(instance.toIpAddr(), instance);
            currentInstanceIds.add(instance.getInstanceId());
        }
        
        Map<String, Instance> instanceMap;
        if (datum != null && null != datum.value) {
            instanceMap = setValid(((Instances) datum.value).getInstanceList(), currentInstances);
        } else {
            instanceMap = new HashMap<>(ips.length);
        }
        
        for (Instance instance : ips) {
            if (!service.getClusterMap().containsKey(instance.getClusterName())) {
                Cluster cluster = new Cluster(instance.getClusterName(), service);
                cluster.init();
                service.getClusterMap().put(instance.getClusterName(), cluster);
                Loggers.SRV_LOG
                        .warn("cluster: {} not found, ip: {}, will create new cluster with default configuration.",
                                instance.getClusterName(), instance.toJson());
            }
            
            if (UtilsAndCommons.UPDATE_INSTANCE_ACTION_REMOVE.equals(action)) {
                instanceMap.remove(instance.getDatumKey());
            } else {
                Instance oldInstance = instanceMap.get(instance.getDatumKey());
                if (oldInstance != null) {
                    instance.setInstanceId(oldInstance.getInstanceId());
                } else {
                    instance.setInstanceId(instance.generateInstanceId(currentInstanceIds));
                }
                instanceMap.put(instance.getDatumKey(), instance);
            }
            
        }
        
        if (instanceMap.size() <= 0 && UtilsAndCommons.UPDATE_INSTANCE_ACTION_ADD.equals(action)) {
            throw new IllegalArgumentException(
                    "ip list can not be empty, service: " + service.getName() + ", ip list: " + JacksonUtils
                            .toJson(instanceMap.values()));
        }
        
        return new ArrayList<>(instanceMap.values());
    }