content: /*
   * Tencent is pleased to support the open source community by making Angel available.
   *
   * Copyright (C) 2017-2018 THL A29 Limited, a Tencent company. All rights reserved.
   *
   * Licensed 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
   *
   * https://opensource.org/licenses/Apache-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 com.tencent.angel.master.client;
  
  import com.google.protobuf.ServiceException;
  import com.tencent.angel.common.location.Location;
  import com.tencent.angel.ipc.TConnection;
  import com.tencent.angel.ipc.TConnectionManager;
  import com.tencent.angel.master.app.AMContext;
  import com.tencent.angel.protobuf.generated.MasterWorkerServiceProtos.GetThreadStackRequest;
  import com.tencent.angel.worker.WorkerAttemptId;
  import com.tencent.angel.worker.WorkerProtocol;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import java.io.IOException;
  
  /**
   * The RPC client from master to a worker, it just for get worker thread stack from worker.
   */
  public class WorkerClient implements WorkerClientInterface {
    private static final Log LOG = LogFactory.getLog(WorkerClient.class);
    /**
     * master context
     */
    private final AMContext context;
  
    /**
     * connection from master to the worker
     */
    private final TConnection connection;
  
    /**
     * rpc protocol
     */
    private final WorkerProtocol worker;
  
    /**
     * Create a WorkerClient
     *
     * @param context         master context
     * @param workerAttemptId worker attempt id
     * @throws IOException
     */
    public WorkerClient(AMContext context, WorkerAttemptId workerAttemptId) throws IOException {
      this.context = context;
      this.connection = TConnectionManager.getConnection(context.getConf());
      Location workerLoc = context.getWorkerManager().getWorker(workerAttemptId.getWorkerId())
        .getWorkerAttempt(workerAttemptId).getLocation();
      LOG.debug("workerLoc= " + workerLoc.toString());
      this.worker = connection.getWorkerService(workerLoc.getIp(), workerLoc.getPort());
    }
  
    @Override public String getThreadStack() throws ServiceException {
      WorkerProtocol workerProtocol = getWorker();
      GetThreadStackRequest request = GetThreadStackRequest.newBuilder().build();
      LOG.info("the class of workerProtocol is " + workerProtocol.getClass());
      return workerProtocol.workerThreadStack(null, request).getStack();
    }
  
    private WorkerProtocol getWorker() {
      return worker;
    }
  }
  