text: /*
   * 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.bookkeeper.stream.protocol;
  
  import io.grpc.Metadata;
  import org.apache.bookkeeper.common.grpc.netty.IdentityBinaryMarshaller;
  import org.apache.bookkeeper.common.grpc.netty.LongBinaryMarshaller;
  import org.apache.bookkeeper.stream.proto.FixedRangeSplitPolicy;
  import org.apache.bookkeeper.stream.proto.RangeKeyType;
  import org.apache.bookkeeper.stream.proto.RetentionPolicy;
  import org.apache.bookkeeper.stream.proto.SegmentRollingPolicy;
  import org.apache.bookkeeper.stream.proto.SizeBasedSegmentRollingPolicy;
  import org.apache.bookkeeper.stream.proto.SplitPolicy;
  import org.apache.bookkeeper.stream.proto.StreamConfiguration;
  import org.apache.bookkeeper.stream.proto.TimeBasedRetentionPolicy;
  
  /**
   * Protocol related constants used across the project.
   */
  public final class ProtocolConstants {
  
      private ProtocolConstants() {
      }
  
      public static final String SCHEME = "stream";
  
      //
      // Storage Container Constants
      //
  
      // the root storage container id
      public static final long ROOT_STORAGE_CONTAINER_ID = 0L;
      // the stream hosts root range
      public static final long ROOT_STREAM_ID = 0L;
      // the root range
      public static final long ROOT_RANGE_ID = 0L;
      // the stream used by each container to store metadata
      public static final long CONTAINER_META_STREAM_ID = 1L;
      // the range used by each container to store metadata
      public static final long CONTAINER_META_RANGE_ID = 0L;
      // the default number of storage containers
      public static final int DEFAULT_NUM_STORAGE_CONTAINERS = 1024;
      // invalid storage container id
      public static final long INVALID_STORAGE_CONTAINER_ID = -1L;
  
      //
      // Stream Related Constants
      //
  
      // invalid namespace id
      public static final long INVALID_NAMESPACE_ID = -1L;
      // invalid stream id
      public static final long INVALID_STREAM_ID = -1L;
      // invalid metadata range id
      public static final long INVALID_RANGE_ID = -1L;
  
      // the minimum data range id - ids between [1L - 1024L) are reserved now.
      public static final long MIN_DATA_RANGE_ID = 1024L;
  
      // the minimum data stream id - stream id between [1L - 1024L) are reserved.
      public static final long MIN_DATA_STREAM_ID = 1024L;
  
      // default split policy
      public static final SplitPolicy DEFAULT_SPLIT_POLICY =
          SplitPolicy.newBuilder()
              .setFixedRangePolicy(
                  FixedRangeSplitPolicy.newBuilder()
                      .setNumRanges(2))
              .build();
      // default rolling policy
      public static final SegmentRollingPolicy DEFAULT_SEGMENT_ROLLING_POLICY =
          SegmentRollingPolicy.newBuilder()
              .setSizePolicy(
                  SizeBasedSegmentRollingPolicy.newBuilder()
                      .setMaxSegmentSize(128 * 1024 * 1024))
              .build();
      // default retention policy
      public static final RetentionPolicy DEFAULT_RETENTION_POLICY =
          RetentionPolicy.newBuilder()
              .setTimePolicy(
                  TimeBasedRetentionPolicy.newBuilder()
                      .setRetentionMinutes(-1))
              .build();
      // default stream configuration
      public static final int INIT_NUM_RANGES = 24;
      public static final int MIN_NUM_RANGES = 24;
      public static final StreamConfiguration DEFAULT_STREAM_CONF =
          StreamConfiguration.newBuilder()
              .setKeyType(RangeKeyType.HASH)
              .setInitialNumRanges(INIT_NUM_RANGES)
              .setMinNumRanges(MIN_NUM_RANGES)
              .setRetentionPolicy(DEFAULT_RETENTION_POLICY)
              .setRollingPolicy(DEFAULT_SEGMENT_ROLLING_POLICY)
              .setSplitPolicy(DEFAULT_SPLIT_POLICY)
              .build();
  
      // storage container request metadata key
      public static final String SC_ID_KEY = "bk-rt-sc-id" + Metadata.BINARY_HEADER_SUFFIX;
  
      // request metadata key for routing requests
      public static final String ROUTING_KEY = "bk-rt-key" + Metadata.BINARY_HEADER_SUFFIX;
      public static final String STREAM_ID_KEY = "bk-rt-sid" + Metadata.BINARY_HEADER_SUFFIX;
      public static final String RANGE_ID_KEY = "bk-rt-rid" + Metadata.BINARY_HEADER_SUFFIX;
  
      // the metadata keys in grpc call metadata
      public static final Metadata.Key<Long> SCID_METADATA_KEY = Metadata.Key.of(
          SC_ID_KEY,
          LongBinaryMarshaller.of()
      );
      public static final Metadata.Key<Long> RID_METADATA_KEY = Metadata.Key.of(
          RANGE_ID_KEY,
          LongBinaryMarshaller.of()
      );
      public static final Metadata.Key<Long> SID_METADATA_KEY = Metadata.Key.of(
          STREAM_ID_KEY,
          LongBinaryMarshaller.of()
      );
      public static final Metadata.Key<byte[]> RK_METADATA_KEY = Metadata.Key.of(
          ROUTING_KEY,
          IdentityBinaryMarshaller.of()
      );
  
  
  }
  