Spring Cloud 2.2.2 源碼之五十九nacos服務端處理查詢實例列表

服務端處理查詢實例列表

我們看查詢服務實例列表在哪裏，在ZoneAwareLoadBalancer的updateListOfServers更新服務中。

這裏會傳UDP端口，就是前篇說的服務器推送服務實例改變的時候會用到。

InstanceController的list查詢實例列表

主要就是獲取了一些信息，這裏要注意udpPort，推送會用到。最後用doSrvIPXT處理，這個什麼方法，好像沒什麼可讀性啊。

  @GetMapping("/list")
    @Secured(parser = NamingResourceParser.class, action = ActionTypes.READ)
    public JSONObject list(HttpServletRequest request) throws Exception {

        String namespaceId = WebUtils.optional(request, CommonParams.NAMESPACE_ID,
            Constants.DEFAULT_NAMESPACE_ID);

        String serviceName = WebUtils.required(request, CommonParams.SERVICE_NAME);
        String agent = WebUtils.getUserAgent(request);
        String clusters = WebUtils.optional(request, "clusters", StringUtils.EMPTY);
        String clientIP = WebUtils.optional(request, "clientIP", StringUtils.EMPTY);
        //UDP端口號
        Integer udpPort = Integer.parseInt(WebUtils.optional(request, "udpPort", "0"));
        String env = WebUtils.optional(request, "env", StringUtils.EMPTY);
        boolean isCheck = Boolean.parseBoolean(WebUtils.optional(request, "isCheck", "false"));

        String app = WebUtils.optional(request, "app", StringUtils.EMPTY);

        String tenant = WebUtils.optional(request, "tid", StringUtils.EMPTY);

        boolean healthyOnly = Boolean.parseBoolean(WebUtils.optional(request, "healthyOnly", "false"));

        return doSrvIPXT(namespaceId, serviceName, agent, clusters, clientIP, udpPort, env, isCheck, app, tenant,
            healthyOnly);
    }

doSrvIPXT返回實例

很長的方法，而且有些邏輯很奇怪，大致就是根據客戶端agent，如果有udp端口的話就會添加到udp推送服務裏去。然後獲取集羣相關的所有實例，進行客戶端IP過濾，最後再健康狀態過濾，如果小於保護閾值，還要開啓保護模式，也就是把不健康的也加入到健康的集合裏，最後封裝數據響應。

 public JSONObject doSrvIPXT(String namespaceId, String serviceName, String agent, String clusters, String clientIP,
                                int udpPort,
                                String env, boolean isCheck, String app, String tid, boolean healthyOnly)
        throws Exception {

        ClientInfo clientInfo = new ClientInfo(agent);//創建客戶端信息
        JSONObject result = new JSONObject();
        Service service = serviceManager.getService(namespaceId, serviceName);//獲取服務

        if (service == null) {//沒有服務
            if (Loggers.SRV_LOG.isDebugEnabled()) {
                Loggers.SRV_LOG.debug("no instance to serve for service: {}", serviceName);
            }
            result.put("name", serviceName);
            result.put("clusters", clusters);
            result.put("hosts", new JSONArray());
            return result;
        }

        checkIfDisabled(service);//檢查服務是否可用
        //緩存事件3秒
        long cacheMillis = switchDomain.getDefaultCacheMillis();

        // now try to enable the push
        try {//有UDP端口的話且裏面判斷客戶端agent類型，好幾種語言版本JAVA PYTHON GO C
            if (udpPort > 0 && pushService.canEnablePush(agent)) {
                //添加要推送的客戶端信息
                pushService.addClient(namespaceId, serviceName,
                    clusters,
                    agent,
                    new InetSocketAddress(clientIP, udpPort),
                    pushDataSource,
                    tid,
                    app);
                cacheMillis = switchDomain.getPushCacheMillis(serviceName);
            }
        } catch (Exception e) {
            Loggers.SRV_LOG.error("[NACOS-API] failed to added push client {}, {}:{}", clientInfo, clientIP, udpPort, e);
            cacheMillis = switchDomain.getDefaultCacheMillis();
        }

        List<Instance> srvedIPs;
        //獲取集羣相關的服務實例
        srvedIPs = service.srvIPs(Arrays.asList(StringUtils.split(clusters, ",")));
        // 客戶端IP過濾
        // filter ips using selector:
        if (service.getSelector() != null && StringUtils.isNotBlank(clientIP)) {
            srvedIPs = service.getSelector().select(clientIP, srvedIPs);
        }

        if (CollectionUtils.isEmpty(srvedIPs)) {

            if (Loggers.SRV_LOG.isDebugEnabled()) {
                Loggers.SRV_LOG.debug("no instance to serve for service: {}", serviceName);
            }

            if (clientInfo.type == ClientInfo.ClientType.JAVA &&
                clientInfo.version.compareTo(VersionUtil.parseVersion("1.0.0")) >= 0) {
                result.put("dom", serviceName);
            } else {
                result.put("dom", NamingUtils.getServiceName(serviceName));
            }

            result.put("hosts", new JSONArray());
            result.put("name", serviceName);
            result.put("cacheMillis", cacheMillis);
            result.put("lastRefTime", System.currentTimeMillis());
            result.put("checksum", service.getChecksum());
            result.put("useSpecifiedURL", false);
            result.put("clusters", clusters);
            result.put("env", env);
            result.put("metadata", service.getMetadata());
            return result;
        }

        Map<Boolean, List<Instance>> ipMap = new HashMap<>(2);
        ipMap.put(Boolean.TRUE, new ArrayList<>());
        ipMap.put(Boolean.FALSE, new ArrayList<>());
        //區分健康狀況的實例
        for (Instance ip : srvedIPs) {
            ipMap.get(ip.isHealthy()).add(ip);
        }

        if (isCheck) {
            result.put("reachProtectThreshold", false);
        }
        //保護模式閾值，默認是，不開啓
        double threshold = service.getProtectThreshold();
        //健康的小於閾值的話就會開啓保護模式，會把不健康的也實例也下發
        if ((float) ipMap.get(Boolean.TRUE).size() / srvedIPs.size() <= threshold) {

            Loggers.SRV_LOG.warn("protect threshold reached, return all ips, service: {}", serviceName);
            if (isCheck) {
                result.put("reachProtectThreshold", true);
            }

            ipMap.get(Boolean.TRUE).addAll(ipMap.get(Boolean.FALSE));
            ipMap.get(Boolean.FALSE).clear();
        }

        if (isCheck) {
            result.put("protectThreshold", service.getProtectThreshold());
            result.put("reachLocalSiteCallThreshold", false);

            return new JSONObject();//返回空對象，很奇怪？是不是寫錯了
        }

        JSONArray hosts = new JSONArray();
        //封裝實例
        for (Map.Entry<Boolean, List<Instance>> entry : ipMap.entrySet()) {
            List<Instance> ips = entry.getValue();

            if (healthyOnly && !entry.getKey()) {
                continue;
            }

            for (Instance instance : ips) {

                // remove disabled instance:
                if (!instance.isEnabled()) {
                    continue;
                }

                JSONObject ipObj = new JSONObject();

                ipObj.put("ip", instance.getIp());
                ipObj.put("port", instance.getPort());
                // deprecated since nacos 1.0.0:
                ipObj.put("valid", entry.getKey());
                ipObj.put("healthy", entry.getKey());
                ipObj.put("marked", instance.isMarked());
                ipObj.put("instanceId", instance.getInstanceId());
                ipObj.put("metadata", instance.getMetadata());
                ipObj.put("enabled", instance.isEnabled());
                ipObj.put("weight", instance.getWeight());
                ipObj.put("clusterName", instance.getClusterName());
                if (clientInfo.type == ClientInfo.ClientType.JAVA &&
                    clientInfo.version.compareTo(VersionUtil.parseVersion("1.0.0")) >= 0) {
                    ipObj.put("serviceName", instance.getServiceName());
                } else {
                    ipObj.put("serviceName", NamingUtils.getServiceName(instance.getServiceName()));
                }

                ipObj.put("ephemeral", instance.isEphemeral());
                hosts.add(ipObj);

            }
        }

        result.put("hosts", hosts);
        if (clientInfo.type == ClientInfo.ClientType.JAVA &&
            clientInfo.version.compareTo(VersionUtil.parseVersion("1.0.0")) >= 0) {
            result.put("dom", serviceName);
        } else {
            result.put("dom", NamingUtils.getServiceName(serviceName));
        }
        result.put("name", serviceName);
        result.put("cacheMillis", cacheMillis);
        result.put("lastRefTime", System.currentTimeMillis());
        result.put("checksum", service.getChecksum());
        result.put("useSpecifiedURL", false);
        result.put("clusters", clusters);
        result.put("env", env);
        result.put("metadata", service.getMetadata());
        return result;
    }

好了，今天就到這裏了，希望對學習理解有幫助，大神看見勿噴，僅爲自己的學習理解，能力有限，請多包涵。