nacos配置中心之ClusterRpcClientProxy源码分析

首先看初始化方法第一行

    /**
     * init after constructor.
     */
    @PostConstruct
    public void init() {
   
        try {
   
            NotifyCenter.registerSubscriber(this);
            List<Member> members = serverMemberManager.allMembersWithoutSelf();
            refresh(members);
            Loggers.CLUSTER
                    .warn("[ClusterRpcClientProxy] success to refresh cluster rpc client on start up,members ={} ",
                            members);
        } catch (NacosException e) {
   
            Loggers.CLUSTER.warn("[ClusterRpcClientProxy] fail to refresh cluster rpc client,{} ", e.getMessage());
        }
        
    }

ClusterRpcClientProxy继承了Subscriber，所以先将自己注册成订阅者，发生MembersChangeEvent事件的时候，会执行onEvent方法

    @Override
    public void onEvent(MembersChangeEvent event) {
   
        try {
   
            List<Member> members = serverMemberManager.allMembersWithoutSelf();
            refresh(members);
        } catch (NacosException e) {
   
            Loggers.CLUSTER.warn("[serverlist] fail to refresh cluster rpc client, event:{}, msg: {} ", event, e.getMessage());
        }
    }

根据以上代码得出结论：ClusterRpcClientProxy初始化和发生MembersChangeEvent事件的时候会执行refresh(members);方法。
继续看refresh方法到底做了什么

  /**
     * init cluster rpc clients.
     *
     * @param members cluster server list member list.
     */
    private void refresh(List<Member> members) throws NacosException {
   
        
        //ensure to create client of new members
        for (Member member : members) {
   
            
            if (MemberUtil.isSupportedLongCon(member)) {
   
                createRpcClientAndStart(member, ConnectionType.GRPC);
            }
        }
        
        //shutdown and remove old members.
        Set<Map.Entry<String, RpcClient>> allClientEntrys = RpcClientFactory.getAllClientEntries();
        Iterator<Map.Entry<String, RpcClient>> iterator = allClientEntrys.iterator();
        List<String> newMemberKeys = members.stream().filter(MemberUtil::isSupportedLongCon)
                .map(this::memberClientKey).collect(Collectors.toList());
        while (iterator.hasNext()) {
   
            Map.Entry<String, RpcClient> next1 = iterator.next();
            if (next1.getKey().startsWith("Cluster-") && !newMemberKeys.contains(next1.getKey())) {
   
                Loggers.CLUSTER.info("member leave,destroy client of member - > : {}", next1.getKey());
                RpcClientFactory.getClient(next1.getKey()).shutdown();
                iterator.remove();
            }
        }
        
    }

继续看createRpcClientAndStart

  private void createRpcClientAndStart(Member member, ConnectionType type) throws NacosException {
   
        Map<String, String> labels = new HashMap<String, String>(2);
        labels.put(RemoteConstants.LABEL_SOURCE, RemoteConstants.LABEL_SOURCE_CLUSTER);
        String memberClientKey = memberClientKey(member);
        RpcClient client = RpcClientFactory.