content: /*
   * Copyright 1999-2023 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.plugin.control.impl;
  
  import com.alibaba.nacos.common.utils.JacksonUtils;
  import com.alibaba.nacos.plugin.control.Loggers;
  import com.alibaba.nacos.plugin.control.connection.ConnectionControlManager;
  import com.alibaba.nacos.plugin.control.connection.ConnectionMetricsCollector;
  import com.alibaba.nacos.plugin.control.connection.request.ConnectionCheckRequest;
  import com.alibaba.nacos.plugin.control.connection.response.ConnectionCheckCode;
  import com.alibaba.nacos.plugin.control.connection.response.ConnectionCheckResponse;
  import com.alibaba.nacos.plugin.control.connection.rule.ConnectionControlRule;
  
  import java.util.Map;
  import java.util.stream.Collectors;
  
  /**
   * Nacos default control plugin implementation.
   *
   * @author shiyiyue
   */
  public class NacosConnectionControlManager extends ConnectionControlManager {
      
      @Override
      public String getName() {
          return "nacos";
      }
      
      public NacosConnectionControlManager() {
          super();
      }
      
      @Override
      public void applyConnectionLimitRule(ConnectionControlRule connectionControlRule) {
          super.connectionControlRule = connectionControlRule;
          Loggers.CONTROL.info("Connection control rule updated to ->" + (this.connectionControlRule == null ? null
                  : JacksonUtils.toJson(this.connectionControlRule)));
          Loggers.CONTROL.warn("Connection control updated, But connection control manager is no limit implementation.");
      }
      
      @Override
      public ConnectionCheckResponse check(ConnectionCheckRequest connectionCheckRequest) {
          ConnectionCheckResponse connectionCheckResponse = new ConnectionCheckResponse();
          connectionCheckResponse.setSuccess(true);
          connectionCheckResponse.setCode(ConnectionCheckCode.PASS_BY_TOTAL);
          int totalCountLimit = connectionControlRule.getCountLimit();
          // If totalCountLimit less than 0, no limit is applied.
          if (totalCountLimit < 0) {
              return connectionCheckResponse;
          }
          
          // Get total connection from metrics
          Map<String, Integer> metricsTotalCount = metricsCollectorList.stream().collect(
                  Collectors.toMap(ConnectionMetricsCollector::getName, ConnectionMetricsCollector::getTotalCount));
          int totalCount = metricsTotalCount.values().stream().mapToInt(Integer::intValue).sum();
          if (totalCount >= totalCountLimit) {
              connectionCheckResponse.setSuccess(false);
              connectionCheckResponse.setCode(ConnectionCheckCode.DENY_BY_TOTAL_OVER);
          }
          return connectionCheckResponse;
      }
      
  }
  