content: /*
   * 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.core.cluster.lookup;
  
  import com.alibaba.nacos.api.exception.NacosException;
  import com.alibaba.nacos.common.http.HttpClientBeanHolder;
  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.model.RestResult;
  import com.alibaba.nacos.common.utils.ExceptionUtil;
  import com.alibaba.nacos.core.cluster.MemberUtil;
  import com.alibaba.nacos.core.utils.GenericType;
  import com.alibaba.nacos.core.utils.GlobalExecutor;
  import com.alibaba.nacos.core.utils.Loggers;
  import com.alibaba.nacos.sys.env.EnvUtil;
  import com.alibaba.nacos.common.utils.StringUtils;
  
  import java.io.Reader;
  import java.io.StringReader;
  import java.util.HashMap;
  import java.util.Map;
  
  import static com.alibaba.nacos.common.constant.RequestUrlConstants.HTTP_PREFIX;
  
  /**
   * Cluster member addressing mode for the address server.
   *
   * @author <a href="mailto:liaochuntao@live.com">liaochuntao</a>
   */
  public class AddressServerMemberLookup extends AbstractMemberLookup {
      
      private final GenericType<String> genericType = new GenericType<String>() { };
      
      public String domainName;
      
      public String addressPort;
      
      public String addressUrl;
      
      public String envIdUrl;
      
      public String addressServerUrl;
      
      private volatile boolean isAddressServerHealth = true;
      
      private int addressServerFailCount = 0;
      
      private int maxFailCount = 12;
      
      private final NacosRestTemplate restTemplate = HttpClientBeanHolder.getNacosRestTemplate(Loggers.CORE);
      
      private volatile boolean shutdown = false;
      
      private static final String HEALTH_CHECK_FAIL_COUNT_PROPERTY = "maxHealthCheckFailCount";
      
      private static final String DEFAULT_HEALTH_CHECK_FAIL_COUNT = "12";
      
      private static final String DEFAULT_SERVER_DOMAIN = "jmenv.tbsite.net";
      
      private static final String DEFAULT_SERVER_POINT = "8080";
      
      private static final int DEFAULT_SERVER_RETRY_TIME = 5;
      
      private static final long DEFAULT_SYNC_TASK_DELAY_MS = 5_000L;
      
      private static final String ADDRESS_SERVER_DOMAIN_ENV = "address_server_domain";
      
      private static final String ADDRESS_SERVER_DOMAIN_PROPERTY = "address.server.domain";
      
      private static final String ADDRESS_SERVER_PORT_ENV = "address_server_port";
      
      private static final String ADDRESS_SERVER_PORT_PROPERTY = "address.server.port";
      
      private static final String ADDRESS_SERVER_URL_ENV = "address_server_url";
      
      private static final String ADDRESS_SERVER_URL_PROPERTY = "address.server.url";
      
      private static final String ADDRESS_SERVER_RETRY_PROPERTY = "nacos.core.address-server.retry";
      
      @Override
      public void doStart() throws NacosException {
          this.maxFailCount = Integer.parseInt(EnvUtil.getProperty(HEALTH_CHECK_FAIL_COUNT_PROPERTY, DEFAULT_HEALTH_CHECK_FAIL_COUNT));
          initAddressSys();
          run();
      }
      
      @Override
      public boolean useAddressServer() {
          return true;
      }
      
      private void initAddressSys() {
          String envDomainName = System.getenv(ADDRESS_SERVER_DOMAIN_ENV);
          if (StringUtils.isBlank(envDomainName)) {
              domainName = EnvUtil.getProperty(ADDRESS_SERVER_DOMAIN_PROPERTY, DEFAULT_SERVER_DOMAIN);
          } else {
              domainName = envDomainName;
          }
          String envAddressPort = System.getenv(ADDRESS_SERVER_PORT_ENV);
          if (StringUtils.isBlank(envAddressPort)) {
              addressPort = EnvUtil.getProperty(ADDRESS_SERVER_PORT_PROPERTY, DEFAULT_SERVER_POINT);
          } else {
              addressPort = envAddressPort;
          }
          String envAddressUrl = System.getenv(ADDRESS_SERVER_URL_ENV);
          if (StringUtils.isBlank(envAddressUrl)) {
              addressUrl = EnvUtil.getProperty(ADDRESS_SERVER_URL_PROPERTY, EnvUtil.getContextPath() + "/" + "serverlist");
          } else {
              addressUrl = envAddressUrl;
          }
          addressServerUrl = HTTP_PREFIX + domainName + ":" + addressPort + addressUrl;
          envIdUrl = HTTP_PREFIX + domainName + ":" + addressPort + "/env";
          
          Loggers.CORE.info("ServerListService address-server port:" + addressPort);
          Loggers.CORE.info("ADDRESS_SERVER_URL:" + addressServerUrl);
      }
      
      @SuppressWarnings("PMD.UndefineMagicConstantRule")
      private void run() throws NacosException {
          // With the address server, you need to perform a synchronous member node pull at startup
          // Repeat three times, successfully jump out
          boolean success = false;
          Throwable ex = null;
          int maxRetry = EnvUtil.getProperty(ADDRESS_SERVER_RETRY_PROPERTY, Integer.class, DEFAULT_SERVER_RETRY_TIME);
          for (int i = 0; i < maxRetry; i++) {
              try {
                  syncFromAddressUrl();
                  success = true;
                  break;
              } catch (Throwable e) {
                  ex = e;
                  Loggers.CLUSTER.error("[serverlist] exception, error : {}", ExceptionUtil.getAllExceptionMsg(ex));
              }
          }
          if (!success) {
              throw new NacosException(NacosException.SERVER_ERROR, ex);
          }
          
          GlobalExecutor.scheduleByCommon(new AddressServerSyncTask(), DEFAULT_SYNC_TASK_DELAY_MS);
      }
      
      @Override
      protected void doDestroy() throws NacosException {
          shutdown = true;
      }
      
      @Override
      public Map<String, Object> info() {
          Map<String, Object> info = new HashMap<>(4);
          info.put("addressServerHealth", isAddressServerHealth);
          info.put("addressServerUrl", addressServerUrl);
          info.put("envIdUrl", envIdUrl);
          info.put("addressServerFailCount", addressServerFailCount);
          return info;
      }
      
      private void syncFromAddressUrl() throws Exception {
          RestResult<String> result = restTemplate
                  .get(addressServerUrl, Header.EMPTY, Query.EMPTY, genericType.getType());
          if (result.ok()) {
              isAddressServerHealth = true;
              Reader reader = new StringReader(result.getData());
              try {
                  afterLookup(MemberUtil.readServerConf(EnvUtil.analyzeClusterConf(reader)));
              } catch (Throwable e) {
                  Loggers.CLUSTER.error("[serverlist] exception for analyzeClusterConf, error : {}",
                          ExceptionUtil.getAllExceptionMsg(e));
              }
              addressServerFailCount = 0;
          } else {
              addressServerFailCount++;
              if (addressServerFailCount >= maxFailCount) {
                  isAddressServerHealth = false;
              }
              Loggers.CLUSTER.error("[serverlist] failed to get serverlist, error code {}", result.getCode());
          }
      }
      
      class AddressServerSyncTask implements Runnable {
          
          @Override
          public void run() {
              if (shutdown) {
                  return;
              }
              try {
                  syncFromAddressUrl();
              } catch (Throwable ex) {
                  addressServerFailCount++;
                  if (addressServerFailCount >= maxFailCount) {
                      isAddressServerHealth = false;
                  }
                  Loggers.CLUSTER.error("[serverlist] exception, error : {}", ExceptionUtil.getAllExceptionMsg(ex));
              } finally {
                  GlobalExecutor.scheduleByCommon(this, DEFAULT_SYNC_TASK_DELAY_MS);
              }
          }
      }
  }
  