hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/interfaces/ContainerPacker.java

/**
 * 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.hadoop.ozone.container.common.interfaces;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.hadoop.ozone.container.common.impl.ContainerData;

/**
 * Service to pack/unpack ContainerData container data to/from a single byte
 * stream.
 */
public interface ContainerPacker<CONTAINERDATA extends ContainerData> {

  /**
   * Extract the container data to the path defined by the container.
   * <p>
   * This doesn't contain the extraction of the container descriptor file.
   *
   * @return the byte content of the descriptor (which won't be written to a
   * file but returned).
   */
  byte[] unpackContainerData(Container<CONTAINERDATA> container,
      InputStream inputStream)
      throws IOException;

  /**
   * Compress all the container data (chunk data, metadata db AND container
   * descriptor) to one single archive.
   */
  void pack(Container<CONTAINERDATA> container, OutputStream destination)
      throws IOException;

  /**
   * Read the descriptor from the finished archive to get the data before
   * importing the container.
   */
  byte[] unpackContainerDescriptor(InputStream inputStream)
      throws IOException;
}