content: /*
   * 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.kafka.streams.state.internals;
  
  import org.apache.kafka.common.utils.Bytes;
  import org.apache.kafka.streams.state.KeyValueStore;
  import org.apache.kafka.streams.state.VersionedBytesStoreSupplier;
  
  public class RocksDbVersionedKeyValueBytesStoreSupplier implements VersionedBytesStoreSupplier {
  
      private final String name;
      private final long historyRetentionMs;
      private final long segmentIntervalMs;
  
      public RocksDbVersionedKeyValueBytesStoreSupplier(final String name,
                                                        final long historyRetentionMs
      ) {
          this(name, historyRetentionMs, defaultSegmentInterval(historyRetentionMs));
      }
  
      public RocksDbVersionedKeyValueBytesStoreSupplier(final String name,
                                                        final long historyRetentionMs,
                                                        final long segmentIntervalMs
      ) {
          this.name = name;
          this.historyRetentionMs = historyRetentionMs;
          this.segmentIntervalMs = segmentIntervalMs;
      }
  
      @Override
      public String name() {
          return name;
      }
  
      @Override
      public long historyRetentionMs() {
          return historyRetentionMs;
      }
  
      public long segmentIntervalMs() {
          return segmentIntervalMs;
      }
  
      @Override
      public KeyValueStore<Bytes, byte[]> get() {
          return new VersionedKeyValueToBytesStoreAdapter(
              new RocksDBVersionedStore(name, metricsScope(), historyRetentionMs, segmentIntervalMs)
          );
      }
  
      @Override
      public String metricsScope() {
          return "rocksdb";
      }
  
      private static long defaultSegmentInterval(final long historyRetentionMs) {
          // Selected somewhat arbitrarily. Optimal value depends heavily on data distribution
          if (historyRetentionMs <= 60_000L) {
              return Math.max(historyRetentionMs / 3, 2_000L);
          } else if (historyRetentionMs <= 300_000L) {
              return Math.max(historyRetentionMs / 5, 20_000L);
          } else if (historyRetentionMs <= 3600_000L) {
              return Math.max(historyRetentionMs / 12, 60_000L);
          } else {
              return Math.max(historyRetentionMs / 24, 300_000L);
          }
      }
  }