001    /**
002    
003     * Licensed to the Apache Software Foundation (ASF) under one
004     * or more contributor license agreements.  See the NOTICE file
005     * distributed with this work for additional information
006     * regarding copyright ownership.  The ASF licenses this file
007     * to you under the Apache License, Version 2.0 (the
008     * "License"); you may not use this file except in compliance
009     * with the License.  You may obtain a copy of the License at
010     *
011     *     http://www.apache.org/licenses/LICENSE-2.0
012     *
013     * Unless required by applicable law or agreed to in writing, software
014     * distributed under the License is distributed on an "AS IS" BASIS,
015     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016     * See the License for the specific language governing permissions and
017     * limitations under the License.
018     */
019    
020    package org.apache.hadoop.yarn.client.api;
021    
022    import java.io.IOException;
023    import java.nio.ByteBuffer;
024    import java.util.Map;
025    
026    import org.apache.hadoop.classification.InterfaceAudience;
027    import org.apache.hadoop.classification.InterfaceAudience.Private;
028    import org.apache.hadoop.classification.InterfaceAudience.Public;
029    import org.apache.hadoop.classification.InterfaceStability;
030    import org.apache.hadoop.service.AbstractService;
031    import org.apache.hadoop.yarn.api.records.Container;
032    import org.apache.hadoop.yarn.api.records.ContainerId;
033    import org.apache.hadoop.yarn.api.records.ContainerLaunchContext;
034    import org.apache.hadoop.yarn.api.records.ContainerStatus;
035    import org.apache.hadoop.yarn.api.records.NodeId;
036    import org.apache.hadoop.yarn.client.api.impl.NMClientImpl;
037    import org.apache.hadoop.yarn.exceptions.YarnException;
038    
039    @InterfaceAudience.Public
040    @InterfaceStability.Stable
041    public abstract class NMClient extends AbstractService {
042    
043      /**
044       * Create a new instance of NMClient.
045       */
046      @Public
047      public static NMClient createNMClient() {
048        NMClient client = new NMClientImpl();
049        return client;
050      }
051    
052      /**
053       * Create a new instance of NMClient.
054       */
055      @Public
056      public static NMClient createNMClient(String name) {
057        NMClient client = new NMClientImpl(name);
058        return client;
059      }
060    
061      @Private
062      protected NMClient(String name) {
063        super(name);
064      }
065    
066      /**
067       * <p>Start an allocated container.</p>
068       *
069       * <p>The <code>ApplicationMaster</code> or other applications that use the
070       * client must provide the details of the allocated container, including the
071       * Id, the assigned node's Id and the token via {@link Container}. In
072       * addition, the AM needs to provide the {@link ContainerLaunchContext} as
073       * well.</p>
074       *
075       * @param container the allocated container
076       * @param containerLaunchContext the context information needed by the
077       *                               <code>NodeManager</code> to launch the
078       *                               container
079       * @return a map between the auxiliary service names and their outputs
080       * @throws YarnException
081       * @throws IOException
082       */
083      public abstract Map<String, ByteBuffer> startContainer(Container container,
084          ContainerLaunchContext containerLaunchContext)
085              throws YarnException, IOException;
086    
087      /**
088       * <p>Stop an started container.</p>
089       *
090       * @param containerId the Id of the started container
091       * @param nodeId the Id of the <code>NodeManager</code>
092       * 
093       * @throws YarnException
094       * @throws IOException
095       */
096      public abstract void stopContainer(ContainerId containerId, NodeId nodeId)
097          throws YarnException, IOException;
098    
099      /**
100       * <p>Query the status of a container.</p>
101       *
102       * @param containerId the Id of the started container
103       * @param nodeId the Id of the <code>NodeManager</code>
104       * 
105       * @return the status of a container
106       * @throws YarnException
107       * @throws IOException
108       */
109      public abstract ContainerStatus getContainerStatus(ContainerId containerId,
110          NodeId nodeId) throws YarnException, IOException;
111    
112      /**
113       * <p>Set whether the containers that are started by this client, and are
114       * still running should be stopped when the client stops. By default, the
115       * feature should be enabled.</p> However, containers will be stopped only  
116       * when service is stopped. i.e. after {@link NMClient#stop()}. 
117       *
118       * @param enabled whether the feature is enabled or not
119       */
120      public abstract void cleanupRunningContainersOnStop(boolean enabled);
121    }