Nacos源码深度解析1-服务注册初始化（客户端）

一.初始化

NamingService naming = NamingFactory.createNamingService(properties);

二.通过反射传入properties生成NacosNamingService的实例

/**
     * Create a new naming service.
     *
     * @param properties naming service properties
     * @return new naming service
     * @throws NacosException nacos exception
     */
    public static NamingService createNamingService(Properties properties) throws NacosException {
        try {
            Class<?> driverImplClass = Class.forName("com.alibaba.nacos.client.naming.NacosNamingService");
            Constructor constructor = driverImplClass.getConstructor(Properties.class);
            NamingService vendorImpl = (NamingService) constructor.newInstance(properties);
            return vendorImpl;
        } catch (Throwable e) {
            throw new NacosException(NacosException.CLIENT_INVALID_PARAM, e);
        }
    }

三.init初始化

 public NacosNamingService(Properties properties) throws NacosException {
        init(properties);
    }

    private void init(Properties properties) throws NacosException {
        ValidatorUtils.checkInitParam(properties);
        this.namespace = InitUtils.initNamespaceForNaming(properties);
        InitUtils.initSerialization();
        //解析serverlist，endpoint
        initServerAddr(properties);
        InitUtils.initWebRootContext();
        //缓存地址C:\Users\admin\nacos\naming\fe3078a2-019d-4fdd-b6cf-22c3117f847d
        initCacheDir();
        //初始化日志信息
        initLogName(properties);
        //监听事件变更
        this.eventDispatcher = new EventDispatcher();
        //1.根据endpoint查找serverlist，nacos服务器地址；2.安全登陆验证
        this.serverProxy = new NamingProxy(this.namespace, this.endpoint, this.serverList, properties);
        //与服务端建立上报机制
        this.beatReactor = new BeatReactor(this.serverProxy, initClientBeatThreadCount(properties));
        this.hostReactor = new HostReactor(this.eventDispatcher, this.serverProxy, beatReactor, this.cacheDir,
                isLoadCacheAtStart(properties), initPollingThreadCount(properties));
    }      

 

四.EventDispatcher 监听事件分发

public EventDispatcher() {

        this.executor = Executors.newSingleThreadExecutor(new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread thread = new Thread(r, "com.alibaba.nacos.naming.client.listener");
                thread.setDaemon(true);

                return thread;
            }
        });

        this.executor.execute(new Notifier());
    }

//changedServices 改变的服务
private final BlockingQueue<ServiceInfo> changedServices = new LinkedBlockingQueue<ServiceInfo>();
//服务 - 监听器回调
private final ConcurrentMap<String, List<EventListener>> observerMap = new ConcurrentHashMap<String, List<EventListener>>();
    private class Notifier implements Runnable {

        @Override
        public void run() {
            while (!closed) {

                ServiceInfo serviceInfo = null;
                try {
                    serviceInfo = changedServices.poll(5, TimeUnit.MINUTES);
                } catch (Exception ignore) {
                }

                if (serviceInfo == null) {
                    continue;
                }

                try {
                    List<EventListener> listeners = observerMap.get(serviceInfo.getKey());

                    if (!CollectionUtils.isEmpty(listeners)) {
                        for (EventListener listener : listeners) {
                            List<Instance> hosts = Collections.unmodifiableList(serviceInfo.getHosts());
                            listener.onEvent(new NamingEvent(serviceInfo.getName(), serviceInfo.getGroupName(),
                                    serviceInfo.getClusters(), hosts));
                        }
                    }

                } catch (Exception e) {
                    NAMING_LOGGER.error("[NA] notify error for service: " + serviceInfo.getName() + ", clusters: "
                            + serviceInfo.getClusters(), e);
                }
            }
        }
    }

五.NamingProxy

1.根据endpoint查找serverlist，nacos服务器地址；2.安全登陆验证

public NamingProxy(String namespaceId, String endpoint, String serverList, Properties properties) {

        this.securityProxy = new SecurityProxy(properties, nacosRestTemplate);
        this.properties = properties;
        this.setServerPort(DEFAULT_SERVER_PORT);
        this.namespaceId = namespaceId;
        this.endpoint = endpoint;
        if (StringUtils.isNotEmpty(serverList)) {
            this.serverList = Arrays.asList(serverList.split(","));
            if (this.serverList.size() == 1) {
                this.nacosDomain = serverList;
            }
        }
        this.initRefreshTask();
    }

private void initRefreshTask() {

        this.executorService = new ScheduledThreadPoolExecutor(2, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread t = new Thread(r);
                t.setName("com.alibaba.nacos.client.naming.updater");
                t.setDaemon(true);
                return t;
            }
        });

        this.executorService.scheduleWithFixedDelay(new Runnable() {
            @Override
            public void run() {
                //根据endpoint定时刷新serverlist地址
                refreshSrvIfNeed();
            }
        }, 0, vipSrvRefInterMillis, TimeUnit.MILLISECONDS);

        this.executorService.scheduleWithFixedDelay(new Runnable() {
            @Override
            public void run() {
                //定时安全登陆验证
                securityProxy.login(getServerList());
            }
        }, 0, securityInfoRefreshIntervalMills, TimeUnit.MILLISECONDS);

        refreshSrvIfNeed();
        this.securityProxy.login(getServerList());
    }

六.初始化心跳线程池

 public BeatReactor(NamingProxy serverProxy, int threadCount) {
        this.serverProxy = serverProxy;
        this.executorService = new ScheduledThreadPoolExecutor(threadCount, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                thread.setName("com.alibaba.nacos.naming.beat.sender");
                return thread;
            }
        });
    }

 

七.HostReactor

ublic HostReactor(EventDispatcher eventDispatcher, NamingProxy serverProxy, BeatReactor beatReactor,
            String cacheDir, boolean loadCacheAtStart, int pollingThreadCount) {
        // init executorService
        this.executor = new ScheduledThreadPoolExecutor(pollingThreadCount, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                thread.setName("com.alibaba.nacos.client.naming.updater");
                return thread;
            }
        });
        this.eventDispatcher = eventDispatcher;
        this.beatReactor = beatReactor;
        this.serverProxy = serverProxy;
        this.cacheDir = cacheDir;
        if (loadCacheAtStart) {
            this.serviceInfoMap = new ConcurrentHashMap<String, ServiceInfo>(DiskCache.read(this.cacheDir));
        } else {
            this.serviceInfoMap = new ConcurrentHashMap<String, ServiceInfo>(16);
        }

        this.updatingMap = new ConcurrentHashMap<String, Object>();
        //容灾备份策略
        this.failoverReactor = new FailoverReactor(this, cacheDir);
        //接收服务器端的数据
        this.pushReceiver = new PushReceiver(this);
    }

 

 

八.PushReceiver

public PushReceiver(HostReactor hostReactor) {
        try {
            this.hostReactor = hostReactor;
            this.udpSocket = new DatagramSocket();
            this.executorService = new ScheduledThreadPoolExecutor(1, new ThreadFactory() {
                @Override
                public Thread newThread(Runnable r) {
                    Thread thread = new Thread(r);
                    thread.setDaemon(true);
                    thread.setName("com.alibaba.nacos.naming.push.receiver");
                    return thread;
                }
            });

            this.executorService.execute(this);
        } catch (Exception e) {
            NAMING_LOGGER.error("[NA] init udp socket failed", e);
        }
    }

九.run 方法

@Override
public void run() {
    while (!closed) {
        try {

            // byte[] is initialized with 0 full filled by default
            byte[] buffer = new byte[UDP_MSS];
            DatagramPacket packet = new DatagramPacket(buffer, buffer.length);

            udpSocket.receive(packet);

            String json = new String(IoUtils.tryDecompress(packet.getData()), UTF_8).trim();
            NAMING_LOGGER.info("received push data: " + json + " from " + packet.getAddress().toString());

            PushPacket pushPacket = JacksonUtils.toObj(json, PushPacket.class);
            String ack;
            if ("dom".equals(pushPacket.type) || "service".equals(pushPacket.type)) {
                //处理从服务端接收的数据
                hostReactor.processServiceJson(pushPacket.data);

                // send ack to server
                ack = "{\"type\": \"push-ack\"" + ", \"lastRefTime\":\"" + pushPacket.lastRefTime + "\", \"data\":"
                        + "\"\"}";
            } else if ("dump".equals(pushPacket.type)) {
                // dump data to server
                ack = "{\"type\": \"dump-ack\"" + ", \"lastRefTime\": \"" + pushPacket.lastRefTime + "\", \"data\":"
                        + "\"" + StringUtils.escapeJavaScript(JacksonUtils.toJson(hostReactor.getServiceInfoMap()))
                        + "\"}";
            } else {
                // do nothing send ack only
                ack = "{\"type\": \"unknown-ack\"" + ", \"lastRefTime\":\"" + pushPacket.lastRefTime
                        + "\", \"data\":" + "\"\"}";
            }
            //发送ack给服务器端
            udpSocket.send(new DatagramPacket(ack.getBytes(UTF_8), ack.getBytes(UTF_8).length,
                    packet.getSocketAddress()));
        } catch (Exception e) {
            if (closed) {
                return;
            }
            NAMING_LOGGER.error("[NA] error while receiving push data", e);
        }
    }
}

 

十.处理服务器端数据

public ServiceInfo processServiceJson(String json) {
        ServiceInfo serviceInfo = JacksonUtils.toObj(json, ServiceInfo.class);
        ServiceInfo oldService = serviceInfoMap.get(serviceInfo.getKey());
        if (serviceInfo.getHosts() == null || !serviceInfo.validate()) {
            //empty or error push, just ignore
            return oldService;
        }

        boolean changed = false;

        if (oldService != null) {
            //处理服务器端数据，判断是新增，删除，还是修改
            if (oldService.getLastRefTime() > serviceInfo.getLastRefTime()) {
                NAMING_LOGGER.warn("out of date data received, old-t: " + oldService.getLastRefTime() + ", new-t: "
                        + serviceInfo.getLastRefTime());
            }
            //向服务缓存map中，放置新的服务
            serviceInfoMap.put(serviceInfo.getKey(), serviceInfo);

            Map<String, Instance> oldHostMap = new HashMap<String, Instance>(oldService.getHosts().size());
            for (Instance host : oldService.getHosts()) {
                oldHostMap.put(host.toInetAddr(), host);
            }

            Map<String, Instance> newHostMap = new HashMap<String, Instance>(serviceInfo.getHosts().size());
            for (Instance host : serviceInfo.getHosts()) {
                newHostMap.put(host.toInetAddr(), host);
            }

            Set<Instance> modHosts = new HashSet<Instance>();
            Set<Instance> newHosts = new HashSet<Instance>();
            Set<Instance> remvHosts = new HashSet<Instance>();

            List<Map.Entry<String, Instance>> newServiceHosts = new ArrayList<Map.Entry<String, Instance>>(
                    newHostMap.entrySet());
            for (Map.Entry<String, Instance> entry : newServiceHosts) {
                Instance host = entry.getValue();
                String key = entry.getKey();
                if (oldHostMap.containsKey(key) && !StringUtils
                        .equals(host.toString(), oldHostMap.get(key).toString())) {
                    modHosts.add(host);
                    continue;
                }

                if (!oldHostMap.containsKey(key)) {
                    newHosts.add(host);
                }
            }

            for (Map.Entry<String, Instance> entry : oldHostMap.entrySet()) {
                Instance host = entry.getValue();
                String key = entry.getKey();
                if (newHostMap.containsKey(key)) {
                    continue;
                }

                if (!newHostMap.containsKey(key)) {
                    remvHosts.add(host);
                }

            }

            if (newHosts.size() > 0) {
                changed = true;
                NAMING_LOGGER.info("new ips(" + newHosts.size() + ") service: " + serviceInfo.getKey() + " -> "
                        + JacksonUtils.toJson(newHosts));
            }

            if (remvHosts.size() > 0) {
                changed = true;
                NAMING_LOGGER.info("removed ips(" + remvHosts.size() + ") service: " + serviceInfo.getKey() + " -> "
                        + JacksonUtils.toJson(remvHosts));
            }

            if (modHosts.size() > 0) {
                changed = true;
                updateBeatInfo(modHosts);
                NAMING_LOGGER.info("modified ips(" + modHosts.size() + ") service: " + serviceInfo.getKey() + " -> "
                        + JacksonUtils.toJson(modHosts));
            }

            serviceInfo.setJsonFromServer(json);

            if (newHosts.size() > 0 || remvHosts.size() > 0 || modHosts.size() > 0) {
                //向事件缓存list changedServices中写入变更事件
                eventDispatcher.serviceChanged(serviceInfo);
                //写入缓存
                DiskCache.write(serviceInfo, cacheDir);
            }

        } else {
            changed = true;
            NAMING_LOGGER.info("init new ips(" + serviceInfo.ipCount() + ") service: " + serviceInfo.getKey() + " -> "
                    + JacksonUtils.toJson(serviceInfo.getHosts()));
            serviceInfoMap.put(serviceInfo.getKey(), serviceInfo);
            eventDispatcher.serviceChanged(serviceInfo);
            serviceInfo.setJsonFromServer(json);
            DiskCache.write(serviceInfo, cacheDir);
        }

        MetricsMonitor.getServiceInfoMapSizeMonitor().set(serviceInfoMap.size());

        if (changed) {
            NAMING_LOGGER.info("current ips:(" + serviceInfo.ipCount() + ") service: " + serviceInfo.getKey() + " -> "
                    + JacksonUtils.toJson(serviceInfo.getHosts()));
        }

        return serviceInfo;
    }

nacos配置加刷新流程图

https://www.processon.com/view/5f2a101d1e08533a629b8bde