code: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.skywalking.oap.server.core.storage.model;
  
  import lombok.Getter;
  import lombok.Setter;
  import org.apache.skywalking.oap.server.core.analysis.record.Record;
  
  import java.util.List;
  
  /**
   * BanyanDBExtension represents extra metadata for models, but specific for BanyanDB usages.
   *
   * @since 9.3.0
   */
  public class BanyanDBModelExtension {
      /**
       * timestampColumn is to identify which column in {@link Record} is providing the timestamp(millisecond) for BanyanDB.
       * BanyanDB stream requires a timestamp in milliseconds
       *
       * @since 9.3.0
       */
      @Getter
      @Setter
      private String timestampColumn;
  
      /**
       * storeIDTag indicates whether a metric stores its ID as a tag.
       * The installer will create a virtual string ID tag with a tree index rule.
       */
      @Getter
      @Setter
      private boolean storeIDTag;
  
      @Getter
      @Setter
      private TopN topN;
  
      public static class TopN {
          /**
           * lru_size defines how many time_buckets are held in the memory.
           * For example, "2" means data points belonging to the latest "2" time_buckets will be persisted.
           * The default value is 2 in the BanyanDB if not set.
           *
           * @since 9.4.0
           */
          @Getter
          @Setter
          private int lruSize;
  
          /**
           * counters_number defines the max number of entries to be tracked during the pre-aggregation.
           * The default value is 1000 in the BanyanDB if not set.
           *
           * @since 9.4.0
           */
          @Getter
          @Setter
          private int countersNumber;
  
          @Setter
          @Getter
          private List<String> groupByTagNames;
      }
  }
  