Merge pull request #1341 from chuntaojun/fix_issue_1214

[#ISSUE 1214] Adjust client error retry mechanism

api/src/main/java/com/alibaba/nacos/api/PropertyKeyConst.java

@@ -46,6 +46,12 @@ public class PropertyKeyConst {
 
     public final static String ENCODE = "encode";
 
+    public final static String CONFIG_LONG_POLL_TIMEOUT = "config.long-poll.timeout";
+
+    public final static String CONFIG_RETRY_TIME = "config.retry.time";
+
+    public final static String MAX_RETRY = "maxRetry";
+
     public final static String NAMING_LOAD_CACHE_AT_START = "namingLoadCacheAtStart";
 
     public final static String NAMING_CLIENT_BEAT_THREAD_COUNT = "namingClientBeatThreadCount";

api/src/main/java/com/alibaba/nacos/api/common/Constants.java

@@ -88,6 +88,26 @@ public class Constants {
      */
     public static final int SO_TIMEOUT = 60000;
 
+    /**
+     * millisecond
+     */
+    public static final int CONFIG_LONG_POLL_TIMEOUT = 30000;
+
+    /**
+     * millisecond
+     */
+    public static final int MIN_CONFIG_LONG_POLL_TIMEOUT = 10000;
+
+    /**
+     * millisecond
+     */
+    public static final int CONFIG_RETRY_TIME = 2000;
+
+    /**
+     * Maximum number of retries
+     */
+    public static final int MAX_RETRY = 3;
+
     /**
      * millisecond
      */

client/src/main/java/com/alibaba/nacos/client/config/NacosConfigService.java

@@ -82,7 +82,7 @@ public class NacosConfigService implements ConfigService {
         initNamespace(properties);
         agent = new MetricsHttpAgent(new ServerHttpAgent(properties));
         agent.start();
-        worker = new ClientWorker(agent, configFilterChainManager);
+        worker = new ClientWorker(agent, configFilterChainManager, properties);
     }
 
     private void initNamespace(Properties properties) {

client/src/main/java/com/alibaba/nacos/client/config/http/ServerHttpAgent.java

@@ -31,6 +31,7 @@ import com.alibaba.nacos.client.utils.ParamUtil;
 import com.alibaba.nacos.client.utils.StringUtils;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.core.type.TypeReference;
+import org.apache.commons.lang3.math.NumberUtils;
 import org.slf4j.Logger;
 import java.io.IOException;
 import java.net.ConnectException;
@@ -67,6 +68,9 @@ public class ServerHttpAgent implements HttpAgent {
         final long endTime = System.currentTimeMillis() + readTimeoutMs;
         final boolean isSSL = false;
 
+        String currentServerAddr = serverListMgr.getCurrentServerAddr();
+        int maxRetry = this.maxRetry;
+
         do {
             try {
                 List<String> newHeaders = getSpasHeaders(paramValues);
@@ -74,7 +78,7 @@ public class ServerHttpAgent implements HttpAgent {
                     newHeaders.addAll(headers);
                 }
                 HttpResult result = HttpSimpleClient.httpGet(
-                    getUrl(serverListMgr.getCurrentServerAddr(), path, isSSL), newHeaders, paramValues, encoding,
+                    getUrl(currentServerAddr, path, isSSL), newHeaders, paramValues, encoding,
                     readTimeoutMs, isSSL);
                 if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR
                     || result.code == HttpURLConnection.HTTP_BAD_GATEWAY
@@ -82,18 +86,29 @@ public class ServerHttpAgent implements HttpAgent {
                     LOGGER.error("[NACOS ConnectException] currentServerAddr: {}, httpCode: {}",
                         serverListMgr.getCurrentServerAddr(), result.code);
                 } else {
+                    // Update the currently available server addr
+                    serverListMgr.updateCurrentServerAddr(currentServerAddr);
                     return result;
                 }
             } catch (ConnectException ce) {
-                LOGGER.error("[NACOS ConnectException] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
+                LOGGER.error("[NACOS ConnectException httpGet] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
-                serverListMgr.refreshCurrentServerAddr();
             } catch (SocketTimeoutException stoe) {
-                LOGGER.error("[NACOS SocketTimeoutException] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
+                LOGGER.error("[NACOS SocketTimeoutException httpGet] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
-                serverListMgr.refreshCurrentServerAddr();
             } catch (IOException ioe) {
-                LOGGER.error("[NACOS IOException] currentServerAddr: " + serverListMgr.getCurrentServerAddr(), ioe);
+                LOGGER.error("[NACOS IOException httpGet] currentServerAddr: " + serverListMgr.getCurrentServerAddr(), ioe);
                 throw ioe;
             }
+
+            if (serverListMgr.getIterator().hasNext()) {
+                currentServerAddr = serverListMgr.getIterator().next();
+            } else {
+                maxRetry --;
+                if (maxRetry < 0) {
+                    throw new ConnectException("[NACOS HTTP-GET] The maximum number of tolerable server reconnection errors has been reached");
+                }
+                serverListMgr.refreshCurrentServerAddr();
+            }
+
         } while (System.currentTimeMillis() <= endTime);
 
         LOGGER.error("no available server");
@@ -105,39 +120,55 @@ public class ServerHttpAgent implements HttpAgent {
                                long readTimeoutMs) throws IOException {
         final long endTime = System.currentTimeMillis() + readTimeoutMs;
         boolean isSSL = false;
+
+        String currentServerAddr = serverListMgr.getCurrentServerAddr();
+        int maxRetry = this.maxRetry;
+
         do {
+
             try {
                 List<String> newHeaders = getSpasHeaders(paramValues);
                 if (headers != null) {
                     newHeaders.addAll(headers);
                 }
+
                 HttpResult result = HttpSimpleClient.httpPost(
-                    getUrl(serverListMgr.getCurrentServerAddr(), path, isSSL), newHeaders, paramValues, encoding,
+                    getUrl(currentServerAddr, path, isSSL), newHeaders, paramValues, encoding,
                     readTimeoutMs, isSSL);
                 if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR
                     || result.code == HttpURLConnection.HTTP_BAD_GATEWAY
                     || result.code == HttpURLConnection.HTTP_UNAVAILABLE) {
-                    LOGGER.error("[NACOS ConnectException] currentServerAddr: {}, httpCode: {}",
+                    LOGGER.error("[NACOS ConnectException httpPost] currentServerAddr: {}, httpCode: {}",
-                        serverListMgr.getCurrentServerAddr(), result.code);
+                        currentServerAddr, result.code);
                 } else {
+                    // Update the currently available server addr
+                    serverListMgr.updateCurrentServerAddr(currentServerAddr);
                     return result;
                 }
             } catch (ConnectException ce) {
-                LOGGER.error("[NACOS ConnectException] currentServerAddr: {}", serverListMgr.getCurrentServerAddr());
+                LOGGER.error("[NACOS ConnectException httpPost] currentServerAddr: {}", currentServerAddr);
-                serverListMgr.refreshCurrentServerAddr();
             } catch (SocketTimeoutException stoe) {
-                LOGGER.error("[NACOS SocketTimeoutException]", "currentServerAddr: {}",
+                LOGGER.error("[NACOS SocketTimeoutException httpPost] currentServerAddr: {}， err : {}",
-                    serverListMgr.getCurrentServerAddr());
+                    currentServerAddr, stoe.getMessage());
-                serverListMgr.refreshCurrentServerAddr();
             } catch (IOException ioe) {
-                LOGGER.error("[NACOS IOException] currentServerAddr: " + serverListMgr.getCurrentServerAddr(), ioe);
+                LOGGER.error("[NACOS IOException httpPost] currentServerAddr: " + currentServerAddr, ioe);
                 throw ioe;
             }
 
+            if (serverListMgr.getIterator().hasNext()) {
+                currentServerAddr = serverListMgr.getIterator().next();
+            } else {
+                maxRetry --;
+                if (maxRetry < 0) {
+                    throw new ConnectException("[NACOS HTTP-POST] The maximum number of tolerable server reconnection errors has been reached");
+                }
+                serverListMgr.refreshCurrentServerAddr();
+            }
+
         } while (System.currentTimeMillis() <= endTime);
 
-        LOGGER.error("no available server");
+        LOGGER.error("no available server, currentServerAddr : {}", currentServerAddr);
-        throw new ConnectException("no available server");
+        throw new ConnectException("no available server, currentServerAddr : " + currentServerAddr);
     }
 
     @Override
@@ -145,6 +176,10 @@ public class ServerHttpAgent implements HttpAgent {
                                  long readTimeoutMs) throws IOException {
         final long endTime = System.currentTimeMillis() + readTimeoutMs;
         boolean isSSL = false;
+
+        String currentServerAddr = serverListMgr.getCurrentServerAddr();
+        int maxRetry = this.maxRetry;
+
         do {
             try {
                 List<String> newHeaders = getSpasHeaders(paramValues);
@@ -152,7 +187,7 @@ public class ServerHttpAgent implements HttpAgent {
                     newHeaders.addAll(headers);
                 }
                 HttpResult result = HttpSimpleClient.httpDelete(
-                    getUrl(serverListMgr.getCurrentServerAddr(), path, isSSL), newHeaders, paramValues, encoding,
+                    getUrl(currentServerAddr, path, isSSL), newHeaders, paramValues, encoding,
                     readTimeoutMs, isSSL);
                 if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR
                     || result.code == HttpURLConnection.HTTP_BAD_GATEWAY
@@ -160,19 +195,29 @@ public class ServerHttpAgent implements HttpAgent {
                     LOGGER.error("[NACOS ConnectException] currentServerAddr: {}, httpCode: {}",
                         serverListMgr.getCurrentServerAddr(), result.code);
                 } else {
+                    // Update the currently available server addr
+                    serverListMgr.updateCurrentServerAddr(currentServerAddr);
                     return result;
                 }
             } catch (ConnectException ce) {
-                LOGGER.error("[NACOS ConnectException] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
+                LOGGER.error("[NACOS ConnectException httpDelete] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
-                serverListMgr.refreshCurrentServerAddr();
             } catch (SocketTimeoutException stoe) {
-                LOGGER.error("[NACOS SocketTimeoutException] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
+                LOGGER.error("[NACOS SocketTimeoutException httpDelete] currentServerAddr:{}", serverListMgr.getCurrentServerAddr());
-                serverListMgr.refreshCurrentServerAddr();
             } catch (IOException ioe) {
-                LOGGER.error("[NACOS IOException] currentServerAddr: " + serverListMgr.getCurrentServerAddr(), ioe);
+                LOGGER.error("[NACOS IOException httpDelete] currentServerAddr: " + serverListMgr.getCurrentServerAddr(), ioe);
                 throw ioe;
             }
 
+            if (serverListMgr.getIterator().hasNext()) {
+                currentServerAddr = serverListMgr.getIterator().next();
+            } else {
+                maxRetry --;
+                if (maxRetry < 0) {
+                    throw new ConnectException("[NACOS HTTP-DELETE] The maximum number of tolerable server reconnection errors has been reached");
+                }
+                serverListMgr.refreshCurrentServerAddr();
+            }
+
         } while (System.currentTimeMillis() <= endTime);
 
         LOGGER.error("no available server");
@@ -208,6 +253,7 @@ public class ServerHttpAgent implements HttpAgent {
     private void init(Properties properties) {
         initEncode(properties);
         initAkSk(properties);
+        initMaxRetry(properties);
     }
 
     private void initEncode(Properties properties) {
@@ -240,6 +286,10 @@ public class ServerHttpAgent implements HttpAgent {
         }
     }
 
+    private void initMaxRetry(Properties properties) {
+        maxRetry = NumberUtils.toInt(String.valueOf(properties.get(PropertyKeyConst.MAX_RETRY)), Constants.MAX_RETRY);
+    }
+
     @Override
     public synchronized void start() throws NacosException {
         serverListMgr.start();
@@ -391,6 +441,7 @@ public class ServerHttpAgent implements HttpAgent {
     private String accessKey;
     private String secretKey;
     private String encode;
+    private int maxRetry = 3;
     private volatile STSCredential sTSCredential;
     final ServerListManager serverListMgr;
 

client/src/main/java/com/alibaba/nacos/client/config/impl/ClientWorker.java

@@ -15,6 +15,7 @@
  */
 package com.alibaba.nacos.client.config.impl;
 
+import com.alibaba.nacos.api.PropertyKeyConst;
 import com.alibaba.nacos.api.common.Constants;
 import com.alibaba.nacos.api.config.listener.Listener;
 import com.alibaba.nacos.api.exception.NacosException;
@@ -28,6 +29,7 @@ import com.alibaba.nacos.client.monitor.MetricsMonitor;
 import com.alibaba.nacos.client.utils.LogUtils;
 import com.alibaba.nacos.client.utils.ParamUtil;
 import com.alibaba.nacos.client.utils.StringUtils;
+import org.apache.commons.lang3.math.NumberUtils;
 import com.alibaba.nacos.client.utils.TenantUtil;
 import org.slf4j.Logger;
 
@@ -35,8 +37,18 @@ import java.io.File;
 import java.io.IOException;
 import java.net.HttpURLConnection;
 import java.net.URLDecoder;
-import java.util.*;
+import java.util.ArrayList;
-import java.util.concurrent.*;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicReference;
 
 import static com.alibaba.nacos.api.common.Constants.LINE_SEPARATOR;
@@ -302,7 +314,7 @@ public class ClientWorker {
     /**
      * 从Server获取值变化了的DataID列表。返回的对象里只有dataId和group是有效的。 保证不返回NULL。
      */
-    List<String> checkUpdateDataIds(List<CacheData> cacheDatas, List<String> inInitializingCacheList) {
+    List<String> checkUpdateDataIds(List<CacheData> cacheDatas, List<String> inInitializingCacheList) throws IOException {
         StringBuilder sb = new StringBuilder();
         for (CacheData cacheData : cacheDatas) {
             if (!cacheData.isUseLocalConfigInfo()) {
@@ -328,10 +340,9 @@ public class ClientWorker {
     /**
      * 从Server获取值变化了的DataID列表。返回的对象里只有dataId和group是有效的。 保证不返回NULL。
      */
-    List<String> checkUpdateConfigStr(String probeUpdateString, boolean isInitializingCacheList) {
+    List<String> checkUpdateConfigStr(String probeUpdateString, boolean isInitializingCacheList) throws IOException {
 
         List<String> params = Arrays.asList(Constants.PROBE_MODIFY_REQUEST, probeUpdateString);
-        long timeout = TimeUnit.SECONDS.toMillis(30L);
 
         List<String> headers = new ArrayList<String>(2);
         headers.add("Long-Pulling-Timeout");
@@ -361,6 +372,7 @@ public class ClientWorker {
         } catch (IOException e) {
             setHealthServer(false);
             LOGGER.error("[" + agent.getName() + "] [check-update] get changed dataId exception", e);
+            throw e;
         }
         return Collections.emptyList();
     }
@@ -403,10 +415,14 @@ public class ClientWorker {
     }
 
     @SuppressWarnings("PMD.ThreadPoolCreationRule")
-    public ClientWorker(final HttpAgent agent, final ConfigFilterChainManager configFilterChainManager) {
+    public ClientWorker(final HttpAgent agent, final ConfigFilterChainManager configFilterChainManager, final Properties properties) {
         this.agent = agent;
         this.configFilterChainManager = configFilterChainManager;
 
+        // Initialize the timeout parameter
+
+        init(properties);
+
         executor = Executors.newScheduledThreadPool(1, new ThreadFactory() {
             @Override
             public Thread newThread(Runnable r) {
@@ -417,17 +433,18 @@ public class ClientWorker {
             }
         });
 
-        executorService = Executors.newCachedThreadPool(new ThreadFactory() {
+        executorService = Executors.newScheduledThreadPool(Runtime.getRuntime().availableProcessors(), new ThreadFactory() {
             @Override
             public Thread newThread(Runnable r) {
                 Thread t = new Thread(r);
-                t.setName("com.alibaba.nacos.client.Worker.longPolling" + agent.getName());
+                t.setName("com.alibaba.nacos.client.Worker.longPolling." + agent.getName());
                 t.setDaemon(true);
                 return t;
             }
         });
 
         executor.scheduleWithFixedDelay(new Runnable() {
+            @Override
             public void run() {
                 try {
                     checkConfigInfo();
@@ -438,6 +455,14 @@ public class ClientWorker {
         }, 1L, 10L, TimeUnit.MILLISECONDS);
     }
 
+    private void init(Properties properties) {
+
+        timeout = Math.max(NumberUtils.toInt(String.valueOf(properties.get(PropertyKeyConst.CONFIG_LONG_POLL_TIMEOUT)),
+            Constants.CONFIG_LONG_POLL_TIMEOUT), Constants.MIN_CONFIG_LONG_POLL_TIMEOUT);
+
+        taskPenaltyTime = NumberUtils.toInt(String.valueOf(properties.get(PropertyKeyConst.CONFIG_RETRY_TIME)), Constants.CONFIG_RETRY_TIME);
+    }
+
     class LongPollingRunnable implements Runnable {
         private int taskId;
 
@@ -445,9 +470,12 @@ public class ClientWorker {
             this.taskId = taskId;
         }
 
+        @Override
         public void run() {
+
+            List<CacheData> cacheDatas = new ArrayList<CacheData>();
+            List<String> inInitializingCacheList = new ArrayList<String>();
             try {
-                List<CacheData> cacheDatas = new ArrayList<CacheData>();
                 // check failover config
                 for (CacheData cacheData : cacheMap.get().values()) {
                     if (cacheData.getTaskId() == taskId) {
@@ -463,7 +491,6 @@ public class ClientWorker {
                     }
                 }
 
-                List<String> inInitializingCacheList = new ArrayList<String>();
                 // check server config
                 List<String> changedGroupKeys = checkUpdateDataIds(cacheDatas, inInitializingCacheList);
 
@@ -497,10 +524,14 @@ public class ClientWorker {
                     }
                 }
                 inInitializingCacheList.clear();
-            } catch (Throwable e) {
+
-                LOGGER.error("longPolling error", e);
-            } finally {
                 executorService.execute(this);
+
+            } catch (Throwable e) {
+
+                // If the rotation training task is abnormal, the next execution time of the task will be punished
+                LOGGER.error("longPolling error : ", e);
+                executorService.schedule(this, taskPenaltyTime, TimeUnit.MILLISECONDS);
             }
         }
     }
@@ -513,8 +544,9 @@ public class ClientWorker {
         this.isHealthServer = isHealthServer;
     }
 
-    private final ScheduledExecutorService executor;
+    final ScheduledExecutorService executor;
-    private final ExecutorService executorService;
+    final ScheduledExecutorService executorService;
+
     /**
      * groupKey -> cacheData
      */
@@ -524,5 +556,7 @@ public class ClientWorker {
     private final HttpAgent agent;
     private final ConfigFilterChainManager configFilterChainManager;
     private boolean isHealthServer = true;
+    private long timeout;
     private double currentLongingTaskCount = 0;
+    private int taskPenaltyTime;
 }

client/src/main/java/com/alibaba/nacos/client/config/impl/ServerListManager.java

@@ -152,6 +152,7 @@ public class ServerListManager {
                     contentPath, serverListName, namespace);
             }
         }
+
     }
 
     private void initParam(Properties properties) {
@@ -265,7 +266,8 @@ public class ServerListManager {
             return;
         }
         serverUrls = new ArrayList<String>(newList);
-        currentServerAddr = iterator().next();
+        iterator = iterator();
+        currentServerAddr = iterator.next();
 
         EventDispatcher.fireEvent(new ServerlistChangeEvent());
         LOGGER.info("[{}] [update-serverlist] serverlist updated to {}", name, serverUrls);
@@ -332,16 +334,26 @@ public class ServerListManager {
     }
 
     public void refreshCurrentServerAddr() {
-        currentServerAddr = iterator().next();
+        iterator = iterator();
+        currentServerAddr = iterator.next();
     }
 
     public String getCurrentServerAddr() {
         if (StringUtils.isBlank(currentServerAddr)) {
-            currentServerAddr = iterator().next();
+            iterator = iterator();
+            currentServerAddr = iterator.next();
         }
         return currentServerAddr;
     }
 
+    public void updateCurrentServerAddr(String currentServerAddr) {
+        this.currentServerAddr = currentServerAddr;
+    }
+
+    public Iterator<String> getIterator() {
+        return iterator;
+    }
+
     public String getContentPath() {
         return contentPath;
     }
@@ -383,11 +395,13 @@ public class ServerListManager {
 
     private volatile String currentServerAddr;
 
+    private Iterator<String> iterator;
     public String serverPort = ParamUtil.getDefaultServerPort();
 
     public String addressServerUrl;
 
     private String serverAddrsStr;
+
 }
 
 /**
@@ -433,14 +447,17 @@ class ServerAddressIterator implements Iterator<String> {
         iter = sorted.iterator();
     }
 
+    @Override
     public boolean hasNext() {
         return iter.hasNext();
     }
 
+    @Override
     public String next() {
         return iter.next().serverIp;
     }
 
+    @Override
     public void remove() {
         throw new UnsupportedOperationException();
     }

config/src/main/java/com/alibaba/nacos/config/server/service/LongPollingService.java

@@ -406,6 +406,7 @@ public class LongPollingService extends AbstractEventListener {
                     }
 
                 }
+
             }, timeoutTime, TimeUnit.MILLISECONDS);
 
             allSubs.add(this);

test/src/test/java/com/alibaba/nacos/test/config/ConfigLongPoll_ITCase.java

@@ -0,0 +1,89 @@
+/*
+ * 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.test.config;
+
+import com.alibaba.nacos.api.NacosFactory;
+import com.alibaba.nacos.api.PropertyKeyConst;
+import com.alibaba.nacos.api.config.ConfigService;
+import com.alibaba.nacos.api.config.listener.Listener;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.config.server.Config;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.web.server.LocalServerPort;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import java.util.Properties;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * @author liaochuntao
+ * @date 2019-06-07 22:24
+ **/
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = Config.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+public class ConfigLongPoll_ITCase {
+
+    @LocalServerPort
+    private int port;
+
+    private ConfigService configService;
+
+    @Before
+    public void init() throws NacosException {
+        Properties properties = new Properties();
+        properties.put(PropertyKeyConst.SERVER_ADDR, "127.0.0.1:" + port);
+        properties.put(PropertyKeyConst.CONFIG_LONG_POLL_TIMEOUT, "20000");
+        properties.put(PropertyKeyConst.CONFIG_RETRY_TIME, 3000);
+        configService = NacosFactory.createConfigService(properties);
+    }
+
+    @Test
+    public void test() throws InterruptedException, NacosException {
+
+        configService.addListener("test", "DEFAULT_GROUP", new Listener() {
+            @Override
+            public Executor getExecutor() {
+                return null;
+            }
+
+            @Override
+            public void receiveConfigInfo(String configInfo) {
+                System.out.println(configInfo);
+            }
+        });
+
+        configService.addListener("test-1", "DEFAULT_GROUP", new Listener() {
+            @Override
+            public Executor getExecutor() {
+                return null;
+            }
+
+            @Override
+            public void receiveConfigInfo(String configInfo) {
+                System.out.println(configInfo);
+            }
+        });
+
+        TimeUnit.SECONDS.sleep(30);
+
+    }
+
+}

test/src/test/java/com/alibaba/nacos/test/naming/DeregisterInstance_ITCase.java

@@ -25,6 +25,7 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.web.server.LocalServerPort;
+import org.springframework.test.annotation.Repeat;
 import org.springframework.test.context.junit4.SpringRunner;
 
 import java.util.Arrays;
@@ -112,7 +113,6 @@ public class DeregisterInstance_ITCase {
     public void dregDomClusterTest() throws Exception {
 
         String serviceName = randomDomainName();
-
         System.out.println(serviceName);
 
         naming.registerInstance(serviceName, "127.0.0.1", TEST_PORT, "c1");