/*
 * 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.transport.server.ratis;

import java.io.File;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import java.util.UUID;
import java.util.EnumMap;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;

import org.apache.hadoop.hdds.conf.ConfigurationSource;
import org.apache.hadoop.hdds.conf.DatanodeRatisServerConfig;
import org.apache.hadoop.hdds.conf.StorageUnit;
import org.apache.hadoop.hdds.HddsConfigKeys;
import org.apache.hadoop.hdds.protocol.DatanodeDetails;
import org.apache.hadoop.hdds.protocol.DatanodeDetails.Port;
import org.apache.hadoop.hdds.protocol.datanode.proto.ContainerProtos.ContainerCommandRequestProto;
import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
import org.apache.hadoop.hdds.protocol.proto.StorageContainerDatanodeProtocolProtos.MetadataStorageReportProto;
import org.apache.hadoop.hdds.protocol.proto.StorageContainerDatanodeProtocolProtos.ClosePipelineInfo;
import org.apache.hadoop.hdds.protocol.proto.StorageContainerDatanodeProtocolProtos.PipelineAction;
import org.apache.hadoop.hdds.protocol.proto.StorageContainerDatanodeProtocolProtos.PipelineReport;
import org.apache.hadoop.hdds.ratis.ContainerCommandRequestMessage;
import org.apache.hadoop.hdds.ratis.RatisHelper;
import org.apache.hadoop.hdds.scm.pipeline.PipelineID;
import org.apache.hadoop.hdds.security.x509.SecurityConfig;
import org.apache.hadoop.hdds.security.x509.certificate.client.CertificateClient;
import org.apache.hadoop.hdds.tracing.TracingUtil;
import org.apache.hadoop.hdds.utils.HAUtils;
import org.apache.hadoop.hdds.utils.HddsServerUtil;
import org.apache.hadoop.ozone.OzoneConfigKeys;
import org.apache.hadoop.ozone.OzoneConsts;
import org.apache.hadoop.ozone.container.common.impl.ContainerData;
import org.apache.hadoop.ozone.container.common.impl.StorageLocationReport;
import org.apache.hadoop.ozone.container.common.interfaces.ContainerDispatcher;
import org.apache.hadoop.ozone.container.common.statemachine.StateContext;
import org.apache.hadoop.ozone.container.common.transport.server.XceiverServerSpi;
import org.apache.hadoop.ozone.container.common.volume.MutableVolumeSet;
import org.apache.hadoop.ozone.container.ozoneimpl.ContainerController;
import org.apache.hadoop.fs.StorageType;
import org.apache.hadoop.hdfs.server.datanode.StorageLocation;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.ThreadFactoryBuilder;
import io.opentracing.Scope;
import io.opentracing.Span;
import io.opentracing.util.GlobalTracer;
import org.apache.ratis.RaftConfigKeys;
import org.apache.ratis.conf.Parameters;
import org.apache.ratis.conf.RaftProperties;
import org.apache.ratis.grpc.GrpcConfigKeys;
import org.apache.ratis.grpc.GrpcTlsConfig;
import org.apache.ratis.netty.NettyConfigKeys;
import org.apache.ratis.proto.RaftProtos;
import org.apache.ratis.proto.RaftProtos.RoleInfoProto;
import org.apache.ratis.protocol.exceptions.NotLeaderException;
import org.apache.ratis.protocol.exceptions.StateMachineException;
import org.apache.ratis.protocol.ClientId;
import org.apache.ratis.protocol.GroupInfoReply;
import org.apache.ratis.protocol.GroupInfoRequest;
import org.apache.ratis.protocol.GroupManagementRequest;
import org.apache.ratis.protocol.RaftClientReply;
import org.apache.ratis.protocol.RaftClientRequest;
import org.apache.ratis.protocol.RaftGroup;
import org.apache.ratis.protocol.RaftGroupId;
import org.apache.ratis.protocol.RaftGroupMemberId;
import org.apache.ratis.protocol.RaftPeerId;
import org.apache.ratis.rpc.RpcType;
import org.apache.ratis.rpc.SupportedRpcType;
import org.apache.ratis.server.RaftServer;
import org.apache.ratis.server.RaftServerConfigKeys;
import org.apache.ratis.server.RaftServerRpc;
import org.apache.ratis.server.protocol.TermIndex;
import org.apache.ratis.util.SizeInBytes;
import org.apache.ratis.util.TimeDuration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import static org.apache.hadoop.hdds.DatanodeVersions.SEPARATE_RATIS_PORTS_AVAILABLE;

/**
 * Creates a ratis server endpoint that acts as the communication layer for
 * Ozone containers.
 */
public final class XceiverServerRatis implements XceiverServerSpi {
  private static final Logger LOG = LoggerFactory
      .getLogger(XceiverServerRatis.class);
  private static final AtomicLong CALL_ID_COUNTER = new AtomicLong();
  private static final List<Integer> DEFAULT_PRIORITY_LIST =
      new ArrayList<>(
          Collections.nCopies(HddsProtos.ReplicationFactor.THREE_VALUE, 0));

  private static long nextCallId() {
    return CALL_ID_COUNTER.getAndIncrement() & Long.MAX_VALUE;
  }

  private int serverPort;
  private int adminPort;
  private int clientPort;
  private final RaftServer server;
  private final List<ThreadPoolExecutor> chunkExecutors;
  private final ContainerDispatcher dispatcher;
  private final ContainerController containerController;
  private ClientId clientId = ClientId.randomId();
  private final StateContext context;
  private long nodeFailureTimeoutMs;
  private boolean isStarted = false;
  private DatanodeDetails datanodeDetails;
  private final ConfigurationSource conf;
  // TODO: Remove the gids set when Ratis supports an api to query active
  // pipelines
  private final Set<RaftGroupId> raftGids = new HashSet<>();
  private final RaftPeerId raftPeerId;
  // pipelines for which I am the leader
  private Map<RaftGroupId, Boolean> groupLeaderMap = new ConcurrentHashMap<>();
  // Timeout used while calling submitRequest directly.
  private long requestTimeout;
  private boolean shouldDeleteRatisLogDirectory;

  /**
   * Maintains a list of active volumes per StorageType.
   */
  private EnumMap<StorageType, List<String>> ratisVolumeMap;

  private XceiverServerRatis(DatanodeDetails dd,
      ContainerDispatcher dispatcher, ContainerController containerController,
      StateContext context, ConfigurationSource conf, Parameters parameters)
      throws IOException {
    this.conf = conf;
    Objects.requireNonNull(dd, "id == null");
    datanodeDetails = dd;
    assignPorts();
    RaftProperties serverProperties = newRaftProperties();
    this.context = context;
    this.dispatcher = dispatcher;
    this.containerController = containerController;
    this.raftPeerId = RatisHelper.toRaftPeerId(dd);
    chunkExecutors = createChunkExecutors(conf);
    nodeFailureTimeoutMs =
            conf.getObject(DatanodeRatisServerConfig.class)
                    .getFollowerSlownessTimeout();
    shouldDeleteRatisLogDirectory =
            conf.getObject(DatanodeRatisServerConfig.class)
                    .shouldDeleteRatisLogDirectory();

    RaftServer.Builder builder =
        RaftServer.newBuilder().setServerId(raftPeerId)
            .setProperties(serverProperties)
            .setStateMachineRegistry(this::getStateMachine)
            .setParameters(parameters);
    this.server = builder.build();
    this.requestTimeout = conf.getTimeDuration(
        HddsConfigKeys.HDDS_DATANODE_RATIS_SERVER_REQUEST_TIMEOUT,
        HddsConfigKeys.HDDS_DATANODE_RATIS_SERVER_REQUEST_TIMEOUT_DEFAULT,
        TimeUnit.MILLISECONDS);
    initializeRatisVolumeMap();
  }

  private void assignPorts() {
    clientPort = determinePort(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_IPC_PORT,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_IPC_PORT_DEFAULT);

    if (datanodeDetails.getInitialVersion() >= SEPARATE_RATIS_PORTS_AVAILABLE) {
      adminPort = determinePort(
          OzoneConfigKeys.DFS_CONTAINER_RATIS_ADMIN_PORT,
          OzoneConfigKeys.DFS_CONTAINER_RATIS_ADMIN_PORT_DEFAULT);
      serverPort = determinePort(
          OzoneConfigKeys.DFS_CONTAINER_RATIS_SERVER_PORT,
          OzoneConfigKeys.DFS_CONTAINER_RATIS_SERVER_PORT_DEFAULT);
    } else {
      adminPort = clientPort;
      serverPort = clientPort;
    }
  }

  private int determinePort(String key, int defaultValue) {
    boolean randomPort = conf.getBoolean(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_IPC_RANDOM_PORT,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_IPC_RANDOM_PORT_DEFAULT);
    return randomPort ? 0 : conf.getInt(key, defaultValue);
  }

  private ContainerStateMachine getStateMachine(RaftGroupId gid) {
    return new ContainerStateMachine(gid, dispatcher, containerController,
        chunkExecutors, this, conf);
  }

  private RaftProperties newRaftProperties() {
    final RaftProperties properties = new RaftProperties();

    // Set rpc type
    final RpcType rpc = setRpcType(properties);

    // set raft segment size
    setRaftSegmentAndWriteBufferSize(properties);

    // set raft segment pre-allocated size
    final int raftSegmentPreallocatedSize =
        setRaftSegmentPreallocatedSize(properties);

    TimeUnit timeUnit;
    long duration;

    // set the configs enable and set the stateMachineData sync timeout
    RaftServerConfigKeys.Log.StateMachineData.setSync(properties, true);
    timeUnit = OzoneConfigKeys.
        DFS_CONTAINER_RATIS_STATEMACHINEDATA_SYNC_TIMEOUT_DEFAULT.getUnit();
    duration = conf.getTimeDuration(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_STATEMACHINEDATA_SYNC_TIMEOUT,
        OzoneConfigKeys.
            DFS_CONTAINER_RATIS_STATEMACHINEDATA_SYNC_TIMEOUT_DEFAULT
            .getDuration(), timeUnit);
    final TimeDuration dataSyncTimeout =
        TimeDuration.valueOf(duration, timeUnit);
    RaftServerConfigKeys.Log.StateMachineData
        .setSyncTimeout(properties, dataSyncTimeout);
    // typically a pipeline close will be initiated after a node failure
    // timeout from Ratis in case a follower does not respond.
    // By this time, all the writeStateMachine calls should be stopped
    // and IOs should fail.
    // Even if the leader is not able to complete write calls within
    // the timeout seconds, it should just fail the operation and trigger
    // pipeline close. failing the writeStateMachine call with limited retries
    // will ensure even the leader initiates a pipeline close if its not
    // able to complete write in the timeout configured.

    // NOTE : the default value for the retry count in ratis is -1,
    // which means retry indefinitely.
    RaftServerConfigKeys.Log.StateMachineData
            .setSyncTimeoutRetry(properties, (int) nodeFailureTimeoutMs /
                    dataSyncTimeout.toIntExact(TimeUnit.MILLISECONDS));

    // set timeout for a retry cache entry
    setTimeoutForRetryCache(properties);

    // Set the ratis leader election timeout
    setRatisLeaderElectionTimeout(properties);

    // Set the maximum cache segments
    RaftServerConfigKeys.Log.setSegmentCacheNumMax(properties, 2);

    // Disable the pre vote feature in Ratis
    RaftServerConfigKeys.LeaderElection.setPreVote(properties, false);

    // Set the ratis storage directory
    Collection<String> storageDirPaths =
            HddsServerUtil.getOzoneDatanodeRatisDirectory(conf);
    List<File> storageDirs= new ArrayList<>(storageDirPaths.size());
    storageDirPaths.stream().forEach(d -> storageDirs.add(new File(d)));

    RaftServerConfigKeys.setStorageDir(properties, storageDirs);

    // For grpc set the maximum message size
    GrpcConfigKeys.setMessageSizeMax(properties,
        SizeInBytes.valueOf(OzoneConsts.OZONE_SCM_CHUNK_MAX_SIZE
                + raftSegmentPreallocatedSize));

    // Set the ratis port number
    if (rpc == SupportedRpcType.GRPC) {
      GrpcConfigKeys.Admin.setPort(properties, adminPort);
      GrpcConfigKeys.Client.setPort(properties, clientPort);
      GrpcConfigKeys.Server.setPort(properties, serverPort);
    } else if (rpc == SupportedRpcType.NETTY) {
      NettyConfigKeys.Server.setPort(properties, serverPort);
    }

    long snapshotThreshold =
        conf.getLong(OzoneConfigKeys.DFS_RATIS_SNAPSHOT_THRESHOLD_KEY,
            OzoneConfigKeys.DFS_RATIS_SNAPSHOT_THRESHOLD_DEFAULT);
    RaftServerConfigKeys.Snapshot.
      setAutoTriggerEnabled(properties, true);
    RaftServerConfigKeys.Snapshot.
      setAutoTriggerThreshold(properties, snapshotThreshold);

    // Set the limit on num/ bytes of pending requests a Ratis leader can hold
    setPendingRequestsLimits(properties);

    int logQueueNumElements =
        conf.getInt(OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_QUEUE_NUM_ELEMENTS,
            OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_QUEUE_NUM_ELEMENTS_DEFAULT);
    final int logQueueByteLimit = (int) conf.getStorageSize(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_QUEUE_BYTE_LIMIT,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_QUEUE_BYTE_LIMIT_DEFAULT,
        StorageUnit.BYTES);
    RaftServerConfigKeys.Log.setQueueElementLimit(
        properties, logQueueNumElements);
    RaftServerConfigKeys.Log.setQueueByteLimit(properties, logQueueByteLimit);

    int numSyncRetries = conf.getInt(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_STATEMACHINEDATA_SYNC_RETRIES,
        OzoneConfigKeys.
            DFS_CONTAINER_RATIS_STATEMACHINEDATA_SYNC_RETRIES_DEFAULT);
    RaftServerConfigKeys.Log.StateMachineData.setSyncTimeoutRetry(properties,
        numSyncRetries);

    // Enable the StateMachineCaching
    RaftServerConfigKeys.Log.StateMachineData.setCachingEnabled(
        properties, true);

    RaftServerConfigKeys.Log.Appender.setInstallSnapshotEnabled(properties,
        false);

    int purgeGap = conf.getInt(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_PURGE_GAP,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_PURGE_GAP_DEFAULT);
    RaftServerConfigKeys.Log.setPurgeGap(properties, purgeGap);

    //Set the number of Snapshots Retained.
    RatisServerConfiguration ratisServerConfiguration =
        conf.getObject(RatisServerConfiguration.class);
    int numSnapshotsRetained =
        ratisServerConfiguration.getNumSnapshotsRetained();
    RaftServerConfigKeys.Snapshot.setRetentionFileNum(properties,
        numSnapshotsRetained);

    // Set properties starting with prefix raft.server
    RatisHelper.createRaftServerProperties(conf, properties);

    return properties;
  }

  private void setRatisLeaderElectionTimeout(RaftProperties properties) {
    long duration;
    TimeUnit leaderElectionMinTimeoutUnit =
        OzoneConfigKeys.
            DFS_RATIS_LEADER_ELECTION_MINIMUM_TIMEOUT_DURATION_DEFAULT
            .getUnit();
    duration = conf.getTimeDuration(
        OzoneConfigKeys.DFS_RATIS_LEADER_ELECTION_MINIMUM_TIMEOUT_DURATION_KEY,
        OzoneConfigKeys.
            DFS_RATIS_LEADER_ELECTION_MINIMUM_TIMEOUT_DURATION_DEFAULT
            .getDuration(), leaderElectionMinTimeoutUnit);
    final TimeDuration leaderElectionMinTimeout =
        TimeDuration.valueOf(duration, leaderElectionMinTimeoutUnit);
    RaftServerConfigKeys.Rpc
        .setTimeoutMin(properties, leaderElectionMinTimeout);
    long leaderElectionMaxTimeout =
        leaderElectionMinTimeout.toLong(TimeUnit.MILLISECONDS) + 200;
    RaftServerConfigKeys.Rpc.setTimeoutMax(properties,
        TimeDuration.valueOf(leaderElectionMaxTimeout, TimeUnit.MILLISECONDS));
  }

  private void setTimeoutForRetryCache(RaftProperties properties) {
    TimeUnit timeUnit;
    long duration;
    timeUnit =
        OzoneConfigKeys.DFS_RATIS_SERVER_RETRY_CACHE_TIMEOUT_DURATION_DEFAULT
            .getUnit();
    duration = conf.getTimeDuration(
        OzoneConfigKeys.DFS_RATIS_SERVER_RETRY_CACHE_TIMEOUT_DURATION_KEY,
        OzoneConfigKeys.DFS_RATIS_SERVER_RETRY_CACHE_TIMEOUT_DURATION_DEFAULT
            .getDuration(), timeUnit);
    final TimeDuration retryCacheTimeout =
        TimeDuration.valueOf(duration, timeUnit);
    RaftServerConfigKeys.RetryCache
        .setExpiryTime(properties, retryCacheTimeout);
  }

  private int setRaftSegmentPreallocatedSize(RaftProperties properties) {
    final int raftSegmentPreallocatedSize = (int) conf.getStorageSize(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_SEGMENT_PREALLOCATED_SIZE_KEY,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_SEGMENT_PREALLOCATED_SIZE_DEFAULT,
        StorageUnit.BYTES);
    int logAppenderQueueNumElements = conf.getInt(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_APPENDER_QUEUE_NUM_ELEMENTS,
        OzoneConfigKeys
            .DFS_CONTAINER_RATIS_LOG_APPENDER_QUEUE_NUM_ELEMENTS_DEFAULT);
    final int logAppenderQueueByteLimit = (int) conf.getStorageSize(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LOG_APPENDER_QUEUE_BYTE_LIMIT,
        OzoneConfigKeys
            .DFS_CONTAINER_RATIS_LOG_APPENDER_QUEUE_BYTE_LIMIT_DEFAULT,
        StorageUnit.BYTES);
    RaftServerConfigKeys.Log.Appender
        .setBufferElementLimit(properties, logAppenderQueueNumElements);
    RaftServerConfigKeys.Log.Appender.setBufferByteLimit(properties,
        SizeInBytes.valueOf(logAppenderQueueByteLimit));
    RaftServerConfigKeys.Log.setPreallocatedSize(properties,
        SizeInBytes.valueOf(raftSegmentPreallocatedSize));
    return raftSegmentPreallocatedSize;
  }

  private void setRaftSegmentAndWriteBufferSize(RaftProperties properties) {
    final int raftSegmentSize = (int)conf.getStorageSize(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_SEGMENT_SIZE_KEY,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_SEGMENT_SIZE_DEFAULT,
        StorageUnit.BYTES);
    RaftServerConfigKeys.Log.setSegmentSizeMax(properties,
        SizeInBytes.valueOf(raftSegmentSize));
    RaftServerConfigKeys.Log.setWriteBufferSize(properties,
            SizeInBytes.valueOf(raftSegmentSize));
  }

  private RpcType setRpcType(RaftProperties properties) {
    final String rpcType = conf.get(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_RPC_TYPE_KEY,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_RPC_TYPE_DEFAULT);
    final RpcType rpc = SupportedRpcType.valueOfIgnoreCase(rpcType);
    RaftConfigKeys.Rpc.setType(properties, rpc);
    return rpc;
  }

  private void setPendingRequestsLimits(RaftProperties properties) {

    final int pendingRequestsByteLimit = (int)conf.getStorageSize(
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LEADER_PENDING_BYTES_LIMIT,
        OzoneConfigKeys.DFS_CONTAINER_RATIS_LEADER_PENDING_BYTES_LIMIT_DEFAULT,
        StorageUnit.BYTES);
    RaftServerConfigKeys.Write.setByteLimit(properties,
        SizeInBytes.valueOf(pendingRequestsByteLimit));
  }

  public static XceiverServerRatis newXceiverServerRatis(
      DatanodeDetails datanodeDetails, ConfigurationSource ozoneConf,
      ContainerDispatcher dispatcher, ContainerController containerController,
      CertificateClient caClient, StateContext context) throws IOException {
    Parameters parameters = createTlsParameters(
        new SecurityConfig(ozoneConf), caClient);

    return new XceiverServerRatis(datanodeDetails, dispatcher,
        containerController, context, ozoneConf, parameters);
  }

  // For gRPC server running DN container service with gPRC TLS
  // In summary:
  // authenticate from server to client is via TLS.
  // authenticate from client to server is via block token (or container token).
  // DN Ratis server act as both SSL client and server and we must pass TLS
  // configuration for both.
  private static Parameters createTlsParameters(SecurityConfig conf,
      CertificateClient caClient) throws IOException {
    Parameters parameters = new Parameters();

    if (conf.isSecurityEnabled() && conf.isGrpcTlsEnabled()) {
      List<X509Certificate> caList = HAUtils.buildCAX509List(caClient,
          conf.getConfiguration());
      GrpcTlsConfig serverConfig = new GrpcTlsConfig(
          caClient.getPrivateKey(), caClient.getCertificate(),
          caList, true);
      GrpcConfigKeys.Server.setTlsConf(parameters, serverConfig);
      GrpcConfigKeys.Admin.setTlsConf(parameters, serverConfig);

      GrpcTlsConfig clientConfig = new GrpcTlsConfig(
          caClient.getPrivateKey(), caClient.getCertificate(),
          caList, false);
      GrpcConfigKeys.Client.setTlsConf(parameters, clientConfig);
    }

    return parameters;
  }

  @Override
  public void start() throws IOException {
    if (!isStarted) {
      LOG.info("Starting {} {}", getClass().getSimpleName(), server.getId());
      for (ThreadPoolExecutor executor : chunkExecutors) {
        executor.prestartAllCoreThreads();
      }
      server.start();

      RaftServerRpc serverRpc = server.getServerRpc();
      clientPort = getRealPort(serverRpc.getClientServerAddress(),
          Port.Name.RATIS);
      adminPort = getRealPort(serverRpc.getAdminServerAddress(),
          Port.Name.RATIS_ADMIN);
      serverPort = getRealPort(serverRpc.getInetSocketAddress(),
          Port.Name.RATIS_SERVER);

      isStarted = true;
    }
  }

  private int getRealPort(InetSocketAddress address, Port.Name name) {
    int realPort = address.getPort();
    datanodeDetails.setPort(DatanodeDetails.newPort(name, realPort));
    LOG.info("{} {} is started using port {} for {}",
        getClass().getSimpleName(), server.getId(), realPort, name);
    return realPort;
  }

  @Override
  public void stop() {
    if (isStarted) {
      try {
        // shutdown server before the executors as while shutting down,
        // some of the tasks would be executed using the executors.
        server.close();
        for (ExecutorService executor : chunkExecutors) {
          executor.shutdown();
        }
        isStarted = false;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }
  }

  @Override
  public int getIPCPort() {
    return clientPort;
  }

  /**
   * Returns the Replication type supported by this end-point.
   *
   * @return enum -- {Stand_Alone, Ratis, Chained}
   */
  @Override
  public HddsProtos.ReplicationType getServerType() {
    return HddsProtos.ReplicationType.RATIS;
  }

  @VisibleForTesting
  public RaftServer getServer() {
    return server;
  }

  public RaftServer.Division getServerDivision() throws IOException {
    return getServerDivision(server.getGroupIds().iterator().next());
  }

  public RaftServer.Division getServerDivision(RaftGroupId id)
      throws IOException {
    return server.getDivision(id);
  }

  private void processReply(RaftClientReply reply) throws IOException {
    // NotLeader exception is thrown only when the raft server to which the
    // request is submitted is not the leader. The request will be rejected
    // and will eventually be executed once the request comes via the leader
    // node.
    NotLeaderException notLeaderException = reply.getNotLeaderException();
    if (notLeaderException != null) {
      throw notLeaderException;
    }
    StateMachineException stateMachineException =
        reply.getStateMachineException();
    if (stateMachineException != null) {
      throw stateMachineException;
    }
  }

  @Override
  public void submitRequest(ContainerCommandRequestProto request,
      HddsProtos.PipelineID pipelineID) throws IOException {
    RaftClientReply reply;
    Span span = TracingUtil
        .importAndCreateSpan(
            "XceiverServerRatis." + request.getCmdType().name(),
            request.getTraceID());
    try (Scope scope = GlobalTracer.get().activateSpan(span)) {

      RaftClientRequest raftClientRequest =
          createRaftClientRequest(request, pipelineID,
              RaftClientRequest.writeRequestType());
      try {
        reply = server.submitClientRequestAsync(raftClientRequest)
            .get(requestTimeout, TimeUnit.MILLISECONDS);
      } catch (Exception e) {
        throw new IOException(e.getMessage(), e);
      }
      processReply(reply);
    } finally {
      span.finish();
    }
  }

  private void  initializeRatisVolumeMap() throws IOException {
    ratisVolumeMap = new EnumMap<>(StorageType.class);
    Collection<String> rawLocations = HddsServerUtil.
            getOzoneDatanodeRatisDirectory(conf);

    for (String locationString : rawLocations) {
      try {
        StorageLocation location = StorageLocation.parse(locationString);
        StorageType type = location.getStorageType();
        ratisVolumeMap.computeIfAbsent(type, k -> new ArrayList<String>(1));
        ratisVolumeMap.get(location.getStorageType()).
                add(location.getUri().getPath());

      } catch (IOException e) {
        LOG.error("Failed to parse the storage location: " +
                locationString, e);
      }
    }
  }

  @Override
  public List<MetadataStorageReportProto> getStorageReport()
      throws IOException {
    List<MetadataStorageReportProto> reportProto = new ArrayList<>();
    for (StorageType storageType : ratisVolumeMap.keySet()) {
      for (String path : ratisVolumeMap.get(storageType)) {
        MetadataStorageReportProto.Builder builder = MetadataStorageReportProto.
                newBuilder();
        builder.setStorageLocation(path);
        builder.setStorageType(StorageLocationReport.
                getStorageTypeProto(storageType));
        reportProto.add(builder.build());
      }
    }
    return reportProto;
  }

  private RaftClientRequest createRaftClientRequest(
      ContainerCommandRequestProto request, HddsProtos.PipelineID pipelineID,
      RaftClientRequest.Type type) {
    return RaftClientRequest.newBuilder()
        .setClientId(clientId)
        .setServerId(server.getId())
        .setGroupId(
            RaftGroupId.valueOf(
                PipelineID.getFromProtobuf(pipelineID).getId()))
        .setCallId(nextCallId())
        .setMessage(ContainerCommandRequestMessage.toMessage(request, null))
        .setType(type)
        .build();
  }

  private GroupInfoRequest createGroupInfoRequest(
      HddsProtos.PipelineID pipelineID) {
    return new GroupInfoRequest(clientId, server.getId(),
        RaftGroupId.valueOf(PipelineID.getFromProtobuf(pipelineID).getId()),
        nextCallId());
  }

  private void handlePipelineFailure(RaftGroupId groupId,
      RoleInfoProto roleInfoProto) {
    String msg;
    UUID datanode = RatisHelper.toDatanodeId(roleInfoProto.getSelf());
    RaftPeerId id = RaftPeerId.valueOf(roleInfoProto.getSelf().getId());
    switch (roleInfoProto.getRole()) {
    case CANDIDATE:
      msg = datanode + " is in candidate state for " +
          roleInfoProto.getCandidateInfo().getLastLeaderElapsedTimeMs() + "ms";
      break;
    case FOLLOWER:
      msg = datanode + " closes pipeline when installSnapshot from leader " +
          "because leader snapshot doesn't contain any data to replay, " +
          "all the log entries prior to the snapshot might have been purged." +
          "So follower should not try to install snapshot from leader but" +
          "can close the pipeline here. It's in follower state for " +
          roleInfoProto.getRoleElapsedTimeMs() + "ms";
      break;
    case LEADER:
      StringBuilder sb = new StringBuilder();
      sb.append(datanode).append(" has not seen follower/s");
      for (RaftProtos.ServerRpcProto follower : roleInfoProto.getLeaderInfo()
          .getFollowerInfoList()) {
        if (follower.getLastRpcElapsedTimeMs() > nodeFailureTimeoutMs) {
          sb.append(" ").append(RatisHelper.toDatanodeId(follower.getId()))
              .append(" for ").append(follower.getLastRpcElapsedTimeMs())
              .append("ms");
        }
      }
      msg = sb.toString();
      break;
    default:
      LOG.error("unknown state: {}", roleInfoProto.getRole());
      throw new IllegalStateException("node" + id + " is in illegal role "
          + roleInfoProto.getRole());
    }

    triggerPipelineClose(groupId, msg,
        ClosePipelineInfo.Reason.PIPELINE_FAILED, false);
  }

  private void triggerPipelineClose(RaftGroupId groupId, String detail,
      ClosePipelineInfo.Reason reasonCode, boolean triggerHB) {
    PipelineID pipelineID = PipelineID.valueOf(groupId.getUuid());
    ClosePipelineInfo.Builder closePipelineInfo =
        ClosePipelineInfo.newBuilder()
            .setPipelineID(pipelineID.getProtobuf())
            .setReason(reasonCode)
            .setDetailedReason(detail);

    PipelineAction action = PipelineAction.newBuilder()
        .setClosePipeline(closePipelineInfo)
        .setAction(PipelineAction.Action.CLOSE)
        .build();
    context.addPipelineActionIfAbsent(action);
    // wait for the next HB timeout or right away?
    if (triggerHB) {
      context.getParent().triggerHeartbeat();
    }
    LOG.error("pipeline Action {} on pipeline {}.Reason : {}",
            action.getAction(), pipelineID,
            action.getClosePipeline().getDetailedReason());
  }

  @Override
  public boolean isExist(HddsProtos.PipelineID pipelineId) {
    return raftGids.contains(
        RaftGroupId.valueOf(PipelineID.getFromProtobuf(pipelineId).getId()));
  }

  private long calculatePipelineBytesWritten(HddsProtos.PipelineID pipelineID) {
    long bytesWritten = 0;
    Iterator<org.apache.hadoop.ozone.container.common.interfaces.Container<?>>
        containerIt = containerController.getContainers();
    while(containerIt.hasNext()) {
      ContainerData containerData = containerIt.next().getContainerData();
      if (containerData.getOriginPipelineId()
          .compareTo(pipelineID.getId()) == 0) {
        bytesWritten += containerData.getWriteBytes();
      }
    }
    return bytesWritten;
  }

  @Override
  public List<PipelineReport> getPipelineReport() {
    try {
      Iterable<RaftGroupId> gids = server.getGroupIds();
      List<PipelineReport> reports = new ArrayList<>();
      for (RaftGroupId groupId : gids) {
        HddsProtos.PipelineID pipelineID = PipelineID
            .valueOf(groupId.getUuid()).getProtobuf();
        reports.add(PipelineReport.newBuilder()
            .setPipelineID(pipelineID)
            .setIsLeader(groupLeaderMap.getOrDefault(groupId, Boolean.FALSE))
            .setBytesWritten(calculatePipelineBytesWritten(pipelineID))
            .build());
      }
      return reports;
    } catch (Exception e) {
      return null;
    }
  }

  @VisibleForTesting
  public List<PipelineID> getPipelineIds() {
    Iterable<RaftGroupId> gids = server.getGroupIds();
    List<PipelineID> pipelineIDs = new ArrayList<>();
    for (RaftGroupId groupId : gids) {
      pipelineIDs.add(PipelineID.valueOf(groupId.getUuid()));
      LOG.info("pipeline id {}", PipelineID.valueOf(groupId.getUuid()));
    }
    return pipelineIDs;
  }

  @Override
  public void addGroup(HddsProtos.PipelineID pipelineId,
      List<DatanodeDetails> peers) throws IOException {
    if (peers.size() == getDefaultPriorityList().size()) {
      addGroup(pipelineId, peers, getDefaultPriorityList());
    } else {
      addGroup(pipelineId, peers,
          new ArrayList<>(Collections.nCopies(peers.size(), 0)));
    }
  }

  @Override
  public void addGroup(HddsProtos.PipelineID pipelineId,
      List<DatanodeDetails> peers,
      List<Integer> priorityList) throws IOException {
    final PipelineID pipelineID = PipelineID.getFromProtobuf(pipelineId);
    final RaftGroupId groupId = RaftGroupId.valueOf(pipelineID.getId());
    final RaftGroup group =
        RatisHelper.newRaftGroup(groupId, peers, priorityList);
    GroupManagementRequest request = GroupManagementRequest.newAdd(
        clientId, server.getId(), nextCallId(), group);

    RaftClientReply reply;
    LOG.debug("Received addGroup request for pipeline {}", pipelineID);

    try {
      reply = server.groupManagement(request);
    } catch (Exception e) {
      throw new IOException(e.getMessage(), e);
    }
    processReply(reply);
    LOG.info("Created group {}", pipelineID);
  }

  @Override
  public void removeGroup(HddsProtos.PipelineID pipelineId)
      throws IOException {
    // if shouldDeleteRatisLogDirectory is set to false, the raft log
    // directory will be renamed and kept aside for debugging.
    // In case, its set to true, the raft log directory will be removed
    GroupManagementRequest request = GroupManagementRequest.newRemove(
        clientId, server.getId(), nextCallId(),
        RaftGroupId.valueOf(PipelineID.getFromProtobuf(pipelineId).getId()),
        shouldDeleteRatisLogDirectory, !shouldDeleteRatisLogDirectory);

    RaftClientReply reply;
    try {
      reply = server.groupManagement(request);
    } catch (Exception e) {
      throw new IOException(e.getMessage(), e);
    }
    processReply(reply);
  }

  void handleNodeSlowness(RaftGroupId groupId, RoleInfoProto roleInfoProto) {
    handlePipelineFailure(groupId, roleInfoProto);
  }

  void handleNoLeader(RaftGroupId groupId, RoleInfoProto roleInfoProto) {
    handlePipelineFailure(groupId, roleInfoProto);
  }

  void handleApplyTransactionFailure(RaftGroupId groupId,
      RaftProtos.RaftPeerRole role) {
    UUID dnId = RatisHelper.toDatanodeId(getServer().getId());
    String msg =
        "Ratis Transaction failure in datanode " + dnId + " with role " + role
            + " .Triggering pipeline close action.";
    triggerPipelineClose(groupId, msg,
        ClosePipelineInfo.Reason.STATEMACHINE_TRANSACTION_FAILED, true);
  }
  /**
   * The fact that the snapshot contents cannot be used to actually catch up
   * the follower, it is the reason to initiate close pipeline and
   * not install the snapshot. The follower will basically never be able to
   * catch up.
   *
   * @param groupId raft group information
   * @param roleInfoProto information about the current node role and
   *                      rpc delay information.
   * @param firstTermIndexInLog After the snapshot installation is complete,
   * return the last included term index in the snapshot.
   */
  void handleInstallSnapshotFromLeader(RaftGroupId groupId,
                                       RoleInfoProto roleInfoProto,
                                       TermIndex firstTermIndexInLog) {
    LOG.warn("Install snapshot notification received from Leader with " +
        "termIndex: {}, terminating pipeline: {}",
        firstTermIndexInLog, groupId);
    handlePipelineFailure(groupId, roleInfoProto);
  }

  /**
   * Notify the Datanode Ratis endpoint of Ratis log failure.
   * Expected to be invoked from the Container StateMachine
   * @param groupId the Ratis group/pipeline for which log has failed
   * @param t exception encountered at the time of the failure
   *
   */
  @VisibleForTesting
  public void handleNodeLogFailure(RaftGroupId groupId, Throwable t) {
    String msg = (t == null) ? "Unspecified failure reported in Ratis log"
        : t.getMessage();

    triggerPipelineClose(groupId, msg,
        ClosePipelineInfo.Reason.PIPELINE_LOG_FAILED, true);
  }

  public long getMinReplicatedIndex(PipelineID pipelineID) throws IOException {
    Long minIndex;
    GroupInfoReply reply = getServer()
        .getGroupInfo(createGroupInfoRequest(pipelineID.getProtobuf()));
    minIndex = RatisHelper.getMinReplicatedIndex(reply.getCommitInfos());
    return minIndex == null ? -1 : minIndex.longValue();
  }

  void notifyGroupRemove(RaftGroupId gid) {
    raftGids.remove(gid);
    // Remove any entries for group leader map
    groupLeaderMap.remove(gid);
  }

  void notifyGroupAdd(RaftGroupId gid) {
    raftGids.add(gid);
    sendPipelineReport();
  }

  void handleLeaderChangedNotification(RaftGroupMemberId groupMemberId,
                                       RaftPeerId raftPeerId1) {
    LOG.info("Leader change notification received for group: {} with new " +
        "leaderId: {}", groupMemberId.getGroupId(), raftPeerId1);
    // Save the reported leader to be sent with the report to SCM
    boolean leaderForGroup = this.raftPeerId.equals(raftPeerId1);
    groupLeaderMap.put(groupMemberId.getGroupId(), leaderForGroup);
    if (context != null && leaderForGroup) {
      // Publish new report from leader
      sendPipelineReport();
    }
  }

  private void sendPipelineReport() {
    if (context !=  null) {
      // TODO: Send IncrementalPipelineReport instead of full PipelineReport
      context.addReport(context.getParent().getContainer().getPipelineReport());
      context.getParent().triggerHeartbeat();
    }
  }

  private static List<ThreadPoolExecutor> createChunkExecutors(
      ConfigurationSource conf) {
    // TODO create single pool with N threads if using non-incremental chunks
    final int threadCountPerDisk = conf.getInt(
        OzoneConfigKeys
            .DFS_CONTAINER_RATIS_NUM_WRITE_CHUNK_THREADS_PER_VOLUME_KEY,
        OzoneConfigKeys
            .DFS_CONTAINER_RATIS_NUM_WRITE_CHUNK_THREADS_PER_VOLUME_DEFAULT);

    final int numberOfDisks =
        MutableVolumeSet.getDatanodeStorageDirs(conf).size();

    ThreadPoolExecutor[] executors =
        new ThreadPoolExecutor[threadCountPerDisk * numberOfDisks];
    for (int i = 0; i < executors.length; i++) {
      ThreadFactory threadFactory = new ThreadFactoryBuilder()
          .setDaemon(true)
          .setNameFormat("ChunkWriter-" + i + "-%d")
          .build();
      BlockingQueue<Runnable> workQueue = new LinkedBlockingDeque<>();
      executors[i] = new ThreadPoolExecutor(1, 1,
          0, TimeUnit.SECONDS, workQueue, threadFactory);
    }
    return ImmutableList.copyOf(executors);
  }

  /**
   * @return list of default priority
   */
  public static List<Integer> getDefaultPriorityList() {
    return DEFAULT_PRIORITY_LIST;
  }
}