[ISSUE #3386] Extract server list maintain logic to ServerListManager

client/src/main/java/com/alibaba/nacos/client/naming/NacosNamingMaintainService.java

@@ -25,10 +25,10 @@
 import com.alibaba.nacos.api.selector.AbstractSelector;
 import com.alibaba.nacos.api.selector.ExpressionSelector;
 import com.alibaba.nacos.api.selector.NoneSelector;
+import com.alibaba.nacos.client.naming.core.ServerListManager;
 import com.alibaba.nacos.client.naming.remote.http.NamingHttpClientProxy;
 import com.alibaba.nacos.client.naming.utils.InitUtils;
 import com.alibaba.nacos.client.utils.ValidatorUtils;
-import com.alibaba.nacos.common.utils.StringUtils;
 
 import java.util.Map;
 import java.util.Properties;
@@ -44,10 +44,6 @@ public class NacosNamingMaintainService implements NamingMaintainService {
 
  private String namespace;
 
- private String endpoint;
-
- private String serverList;
-
  private NamingHttpClientProxy serverProxy;
 
  public NacosNamingMaintainService(String serverList) throws NacosException {
@@ -64,17 +60,9 @@ private void init(Properties properties) throws NacosException {
  ValidatorUtils.checkInitParam(properties);
  namespace = InitUtils.initNamespaceForNaming(properties);
  InitUtils.initSerialization();
- initServerAddr(properties);
  InitUtils.initWebRootContext();
- serverProxy = new NamingHttpClientProxy(namespace, endpoint, serverList, properties);
- }
-
- private void initServerAddr(Properties properties) {
- serverList = properties.getProperty(PropertyKeyConst.SERVER_ADDR);
- endpoint = InitUtils.initEndpoint(properties);
- if (StringUtils.isNotEmpty(endpoint)) {
- serverList = "";
- }
+ ServerListManager serverListManager = new ServerListManager(properties);
+ serverProxy = new NamingHttpClientProxy(namespace, serverListManager, properties);
  }
 
  @Override

client/src/main/java/com/alibaba/nacos/client/naming/NacosNamingService.java

@@ -30,12 +30,12 @@
 import com.alibaba.nacos.client.naming.core.Balancer;
 import com.alibaba.nacos.client.naming.core.EventDispatcher;
 import com.alibaba.nacos.client.naming.core.HostReactor;
+import com.alibaba.nacos.client.naming.core.ServerListManager;
 import com.alibaba.nacos.client.naming.remote.gprc.NamingGrpcClientProxy;
 import com.alibaba.nacos.client.naming.remote.http.NamingHttpClientProxy;
 import com.alibaba.nacos.client.naming.utils.CollectionUtils;
 import com.alibaba.nacos.client.naming.utils.InitUtils;
 import com.alibaba.nacos.client.naming.utils.UtilAndComs;
-import com.alibaba.nacos.client.remote.ServerListFactory;
 import com.alibaba.nacos.client.utils.ValidatorUtils;
 import com.alibaba.nacos.common.utils.ConvertUtils;
 import com.alibaba.nacos.common.utils.StringUtils;
@@ -44,7 +44,6 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.Properties;
-import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * Nacos Naming Service.
@@ -59,10 +58,6 @@ public class NacosNamingService implements NamingService {
  */
  private String namespace;
 
- private String endpoint;
-
- private String serverList;
-
  private String cacheDir;
 
  private String logName;
@@ -91,34 +86,18 @@ private void init(Properties properties) throws NacosException {
  ValidatorUtils.checkInitParam(properties);
  this.namespace = InitUtils.initNamespaceForNaming(properties);
  InitUtils.initSerialization();
- initServerAddr(properties);
  InitUtils.initWebRootContext();
  initCacheDir();
  initLogName(properties);
 
+ ServerListManager serverListManager = new ServerListManager(properties);
  this.eventDispatcher = new EventDispatcher();
- this.serverProxy = new NamingHttpClientProxy(this.namespace, this.endpoint, this.serverList, properties);
+ this.serverProxy = new NamingHttpClientProxy(this.namespace, serverListManager, properties);
  this.beatReactor = new BeatReactor(this.serverProxy, initClientBeatThreadCount(properties));
  this.hostReactor = new HostReactor(this.eventDispatcher, this.serverProxy, beatReactor, this.cacheDir,
  isLoadCacheAtStart(properties), initPollingThreadCount(properties));
  this.grpcClientProxy = new NamingGrpcClientProxy(namespace, hostReactor);
- grpcClientProxy.start(new ServerListFactory() {
-
- private final AtomicInteger index = new AtomicInteger();
-
- private final String[] serverLists = serverList.split(",");
-
- @Override
- public String genNextServer() {
- int nextIndex = index.getAndIncrement() % serverLists.length;
- return serverLists[nextIndex];
- }
-
- @Override
- public String getCurrentServer() {
- return serverLists[index.get() % serverLists.length];
- }
- });
+ grpcClientProxy.start(serverListManager);
  }
 
  private int initClientBeatThreadCount(Properties properties) {
@@ -151,14 +130,6 @@ private boolean isLoadCacheAtStart(Properties properties) {
  return loadCacheAtStart;
  }
 
- private void initServerAddr(Properties properties) {
- serverList = properties.getProperty(PropertyKeyConst.SERVER_ADDR);
- endpoint = InitUtils.initEndpoint(properties);
- if (StringUtils.isNotEmpty(endpoint)) {
- serverList = "";
- }
- }
-
  private void initLogName(Properties properties) {
  logName = System.getProperty(UtilAndComs.NACOS_NAMING_LOG_NAME);
  if (StringUtils.isEmpty(logName)) {

client/src/main/java/com/alibaba/nacos/client/naming/core/ServerListManager.java

@@ -0,0 +1,180 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.alibaba.nacos.client.naming.core;
+
+import com.alibaba.nacos.api.PropertyKeyConst;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.naming.remote.http.NamingHttpClientManager;
+import com.alibaba.nacos.client.naming.utils.CollectionUtils;
+import com.alibaba.nacos.client.naming.utils.InitUtils;
+import com.alibaba.nacos.client.naming.utils.NamingHttpUtil;
+import com.alibaba.nacos.client.remote.ServerListFactory;
+import com.alibaba.nacos.common.executor.NameThreadFactory;
+import com.alibaba.nacos.common.http.HttpRestResult;
+import com.alibaba.nacos.common.http.client.NacosRestTemplate;
+import com.alibaba.nacos.common.http.param.Header;
+import com.alibaba.nacos.common.http.param.Query;
+import com.alibaba.nacos.common.lifecycle.Closeable;
+import com.alibaba.nacos.common.utils.IoUtils;
+import com.alibaba.nacos.common.utils.StringUtils;
+import com.alibaba.nacos.common.utils.ThreadUtils;
+
+import java.io.IOException;
+import java.io.StringReader;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Properties;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static com.alibaba.nacos.client.utils.LogUtils.NAMING_LOGGER;
+
+/**
+ * Server list manager.
+ *
+ * @author xiweng.yy
+ */
+public class ServerListManager implements ServerListFactory, Closeable {
+
+ private final NacosRestTemplate nacosRestTemplate = NamingHttpClientManager.getInstance().getNacosRestTemplate();
+
+ private final long refreshServerListInternal = TimeUnit.SECONDS.toMillis(30);
+
+ private final AtomicInteger currentIndex = new AtomicInteger();
+
+ private List<String> serversFromEndpoint = new ArrayList<String>();
+
+ private List<String> serverList = new ArrayList<String>();
+
+ private ScheduledExecutorService refreshServerListExecutor;
+
+ private String endpoint;
+
+ private String nacosDomain;
+
+ private long lastServerListRefreshTime = 0L;
+
+ public ServerListManager(Properties properties) {
+ initServerAddr(properties);
+ }
+
+ private void initServerAddr(Properties properties) {
+ this.endpoint = InitUtils.initEndpoint(properties);
+ if (StringUtils.isNotEmpty(endpoint)) {
+ this.serversFromEndpoint = getServerListFromEndpoint();
+ refreshServerListExecutor = new ScheduledThreadPoolExecutor(1,
+ new NameThreadFactory("com.alibaba.nacos.client.naming.server.list.refresher"));
+ refreshServerListExecutor.scheduleWithFixedDelay(new Runnable() {
+ @Override
+ public void run() {
+ refreshServerListIfNeed();
+ }
+ }, 0, refreshServerListInternal, TimeUnit.MILLISECONDS);
+ } else {
+ String serverListFromProps = properties.getProperty(PropertyKeyConst.SERVER_ADDR);
+ if (StringUtils.isNotEmpty(serverListFromProps)) {
+ this.serverList.addAll(Arrays.asList(serverListFromProps.split(",")));
+ if (this.serverList.size() == 1) {
+ this.nacosDomain = serverListFromProps;
+ }
+ }
+ }
+ }
+
+ private List<String> getServerListFromEndpoint() {
+ try {
+ String urlString = "http://" + endpoint + "/nacos/serverlist";
+ Header header = NamingHttpUtil.builderHeader();
+ HttpRestResult<String> restResult = nacosRestTemplate.get(urlString, header, Query.EMPTY, String.class);
+ if (!restResult.ok()) {
+ throw new IOException(
+ "Error while requesting: " + urlString + "'. Server returned: " + restResult.getCode());
+ }
+ String content = restResult.getData();
+ List<String> list = new ArrayList<String>();
+ for (String line : IoUtils.readLines(new StringReader(content))) {
+ if (!line.trim().isEmpty()) {
+ list.add(line.trim());
+ }
+ }
+ return list;
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ return null;
+ }
+
+ private void refreshServerListIfNeed() {
+ try {
+ if (!CollectionUtils.isEmpty(serverList)) {
+ NAMING_LOGGER.debug("server list provided by user: " + serverList);
+ return;
+ }
+ if (System.currentTimeMillis() - lastServerListRefreshTime < refreshServerListInternal) {
+ return;
+ }
+ List<String> list = getServerListFromEndpoint();
+ if (CollectionUtils.isEmpty(list)) {
+ throw new Exception("Can not acquire Nacos list");
+ }
+ if (!CollectionUtils.isEqualCollection(list, serversFromEndpoint)) {
+ NAMING_LOGGER.info("[SERVER-LIST] server list is updated: " + list);
+ }
+ serversFromEndpoint = list;
+ lastServerListRefreshTime = System.currentTimeMillis();
+ } catch (Throwable e) {
+ NAMING_LOGGER.warn("failed to update server list", e);
+ }
+ }
+
+ public boolean isDomain() {
+ return StringUtils.isNotBlank(nacosDomain);
+ }
+
+ public String getNacosDomain() {
+ return nacosDomain;
+ }
+
+ public List<String> getServerList() {
+ return serverList.isEmpty() ? serversFromEndpoint : serverList;
+ }
+
+ @Override
+ public String genNextServer() {
+ int index = currentIndex.incrementAndGet() % getServerList().size();
+ return getServerList().get(index);
+ }
+
+ @Override
+ public String getCurrentServer() {
+ return getServerList().get(currentIndex.get() % getServerList().size());
+ }
+
+ @Override
+ public void shutdown() throws NacosException {
+ String className = this.getClass().getName();
+ NAMING_LOGGER.info("{} do shutdown begin", className);
+ if (null != refreshServerListExecutor) {
+ ThreadUtils.shutdownThreadPool(refreshServerListExecutor, NAMING_LOGGER);
+ }
+ NamingHttpClientManager.getInstance().shutdown();
+ NAMING_LOGGER.info("{} do shutdown stop", className);
+ }
+}