/**
 * 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.hdfs.protocolPB;

import java.io.Closeable;
import java.io.IOException;
import java.net.InetSocketAddress;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hdfs.protocol.proto.DatanodeProtocolProtos.HeartbeatRequestProto;
import org.apache.hadoop.hdfs.server.protocol.DatanodeLifelineProtocol;
import org.apache.hadoop.hdfs.server.protocol.DatanodeRegistration;
import org.apache.hadoop.hdfs.server.protocol.StorageReport;
import org.apache.hadoop.hdfs.server.protocol.VolumeFailureSummary;
import org.apache.hadoop.ipc.ProtobufHelper;
import org.apache.hadoop.ipc.ProtobufRpcEngine;
import org.apache.hadoop.ipc.ProtocolMetaInterface;
import org.apache.hadoop.ipc.RPC;
import org.apache.hadoop.ipc.RpcClientUtil;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.UserGroupInformation;

import com.google.protobuf.RpcController;
import com.google.protobuf.ServiceException;

/**
 * This class is the client side translator to translate the requests made on
 * {@link DatanodeLifelineProtocol} interfaces to the RPC server implementing
 * {@link DatanodeLifelineProtocolPB}.
 */
@InterfaceAudience.Private
public class DatanodeLifelineProtocolClientSideTranslatorPB implements
    ProtocolMetaInterface, DatanodeLifelineProtocol, Closeable {

  /** RpcController is not used and hence is set to null. */
  private static final RpcController NULL_CONTROLLER = null;

  private final DatanodeLifelineProtocolPB rpcProxy;

  public DatanodeLifelineProtocolClientSideTranslatorPB(
      InetSocketAddress nameNodeAddr, Configuration conf) throws IOException {
    RPC.setProtocolEngine(conf, DatanodeLifelineProtocolPB.class,
        ProtobufRpcEngine.class);
    UserGroupInformation ugi = UserGroupInformation.getCurrentUser();
    rpcProxy = createNamenode(nameNodeAddr, conf, ugi);
  }

  private static DatanodeLifelineProtocolPB createNamenode(
      InetSocketAddress nameNodeAddr, Configuration conf,
      UserGroupInformation ugi) throws IOException {
    return RPC.getProxy(DatanodeLifelineProtocolPB.class,
        RPC.getProtocolVersion(DatanodeLifelineProtocolPB.class), nameNodeAddr,
        ugi, conf,
        NetUtils.getSocketFactory(conf, DatanodeLifelineProtocolPB.class));
  }

  @Override
  public void close() throws IOException {
    RPC.stopProxy(rpcProxy);
  }

  @Override
  public void sendLifeline(DatanodeRegistration registration,
      StorageReport[] reports, long cacheCapacity, long cacheUsed,
      int xmitsInProgress, int xceiverCount, int failedVolumes,
      VolumeFailureSummary volumeFailureSummary) throws IOException {
    HeartbeatRequestProto.Builder builder = HeartbeatRequestProto.newBuilder()
        .setRegistration(PBHelper.convert(registration))
        .setXmitsInProgress(xmitsInProgress).setXceiverCount(xceiverCount)
        .setFailedVolumes(failedVolumes);
    builder.addAllReports(PBHelper.convertStorageReports(reports));
    if (cacheCapacity != 0) {
      builder.setCacheCapacity(cacheCapacity);
    }
    if (cacheUsed != 0) {
      builder.setCacheUsed(cacheUsed);
    }
    if (volumeFailureSummary != null) {
      builder.setVolumeFailureSummary(PBHelper.convertVolumeFailureSummary(
          volumeFailureSummary));
    }
    try {
      rpcProxy.sendLifeline(NULL_CONTROLLER, builder.build());
    } catch (ServiceException se) {
      throw ProtobufHelper.getRemoteException(se);
    }
  }

  @Override // ProtocolMetaInterface
  public boolean isMethodSupported(String methodName)
      throws IOException {
    return RpcClientUtil.isMethodSupported(rpcProxy,
        DatanodeLifelineProtocolPB.class, RPC.RpcKind.RPC_PROTOCOL_BUFFER,
        RPC.getProtocolVersion(DatanodeLifelineProtocolPB.class), methodName);
  }
}