001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.hadoop.yarn.api.protocolrecords;
020
021import java.nio.ByteBuffer;
022import java.util.Map;
023
024import org.apache.hadoop.classification.InterfaceAudience.Public;
025import org.apache.hadoop.classification.InterfaceStability.Stable;
026import org.apache.hadoop.yarn.api.ContainerManager;
027
028/**
029 * <p>The response sent by the <code>NodeManager</code> to the 
030 * <code>ApplicationMaster</code> when asked to <em>start</em> an
031 * allocated container.</p>
032 * 
033 * @see ContainerManager#startContainer(StartContainerRequest)
034 */
035@Public
036@Stable
037public interface StartContainerResponse {
038  /**
039   * <p>Get the responses from all auxiliary services running on the 
040   * <code>NodeManager</code>.</p>
041   * <p>The responses are returned as a Map between the auxiliary service names
042   * and their corresponding opaque blob <code>ByteBuffer</code>s</p> 
043   * @return a Map between the auxiliary service names and their outputs
044   */
045  Map<String, ByteBuffer> getAllServiceResponse();
046
047  /**
048   * Get the response from a single auxiliary service running on the
049   * <code>NodeManager</code>
050   * 
051   * @param key The auxiliary service name whose response is desired.
052   * @return The opaque blob <code>ByteBuffer</code> returned by the auxiliary
053   * service.
054   */
055  ByteBuffer getServiceResponse(String key);
056
057  /**
058   * Add to the list of auxiliary services which have been started on the
059   * <code>NodeManager</code>. This is done only once when the
060   * <code>NodeManager</code> starts up
061   * @param serviceResponse A map from auxiliary service names to the opaque
062   * blob <code>ByteBuffer</code>s for that auxiliary service
063   */
064  void addAllServiceResponse(Map<String, ByteBuffer> serviceResponse);
065
066  /**
067   * Add to the list of auxiliary services which have been started on the
068   * <code>NodeManager</code>. This is done only once when the
069   * <code>NodeManager</code> starts up
070   * 
071   * @param key The auxiliary service name
072   * @param value The opaque blob <code>ByteBuffer</code> managed by the
073   * auxiliary service
074   */
075  void setServiceResponse(String key, ByteBuffer value);
076
077  /**
078   * Remove a single auxiliary service from the StartContainerResponse object
079   * @param key The auxiliary service to remove
080   */
081  void removeServiceResponse(String key);
082  
083  /**
084   * Remove all the auxiliary services from the StartContainerResponse object
085   */
086  void clearServiceResponse();
087}