/**
 * 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.yarn.server.resourcemanager;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.yarn.ams.ApplicationMasterServiceContext;
import org.apache.hadoop.yarn.ams.ApplicationMasterServiceUtils;
import org.apache.hadoop.yarn.ams.ApplicationMasterServiceProcessor;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest;
import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest;
import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterResponse;
import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterRequest;
import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterResponse;
import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
import org.apache.hadoop.yarn.api.records.CollectorInfo;
import org.apache.hadoop.yarn.api.records.Container;
import org.apache.hadoop.yarn.api.records.ContainerId;
import org.apache.hadoop.yarn.api.records.ContainerUpdateType;
import org.apache.hadoop.yarn.api.records.NMToken;
import org.apache.hadoop.yarn.api.records.NodeId;
import org.apache.hadoop.yarn.api.records.NodeReport;
import org.apache.hadoop.yarn.api.records.PreemptionContainer;
import org.apache.hadoop.yarn.api.records.PreemptionContract;
import org.apache.hadoop.yarn.api.records.PreemptionMessage;
import org.apache.hadoop.yarn.api.records.PreemptionResourceRequest;
import org.apache.hadoop.yarn.api.records.Resource;
import org.apache.hadoop.yarn.api.records.ResourceBlacklistRequest;
import org.apache.hadoop.yarn.api.records.ResourceRequest;
import org.apache.hadoop.yarn.api.records.StrictPreemptionContract;
import org.apache.hadoop.yarn.api.records.UpdateContainerError;
import org.apache.hadoop.yarn.conf.YarnConfiguration;
import org.apache.hadoop.yarn.exceptions.InvalidContainerReleaseException;
import org.apache.hadoop.yarn.exceptions.InvalidResourceBlacklistRequestException;
import org.apache.hadoop.yarn.exceptions.InvalidResourceRequestException;
import org.apache.hadoop.yarn.exceptions.YarnException;
import org.apache.hadoop.yarn.factories.RecordFactory;
import org.apache.hadoop.yarn.factory.providers.RecordFactoryProvider;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMApp;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttempt;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt
    .RMAppAttemptState;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.event.RMAppAttemptRegistrationEvent;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.event
    .RMAppAttemptStatusupdateEvent;
import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.event
    .RMAppAttemptUnregistrationEvent;
import org.apache.hadoop.yarn.server.resourcemanager.rmnode.RMNode;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler
    .AbstractYarnScheduler;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.Allocation;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ContainerUpdates;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler
    .SchedulerNodeReport;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.YarnScheduler;
import org.apache.hadoop.yarn.server.utils.BuilderUtils;
import org.apache.hadoop.yarn.util.resource.Resources;

import java.io.IOException;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

/**
 * This is the default Application Master Service processor. It has be the
 * last processor in the @{@link AMSProcessingChain}.
 */
final class DefaultAMSProcessor implements ApplicationMasterServiceProcessor {

  private static final Log LOG = LogFactory.getLog(DefaultAMSProcessor.class);

  private final static List<Container> EMPTY_CONTAINER_LIST =
      new ArrayList<Container>();
  protected static final Allocation EMPTY_ALLOCATION = new Allocation(
      EMPTY_CONTAINER_LIST, Resources.createResource(0), null, null, null);

  private final RecordFactory recordFactory =
      RecordFactoryProvider.getRecordFactory(null);

  private RMContext rmContext;

  @Override
  public void init(ApplicationMasterServiceContext amsContext,
      ApplicationMasterServiceProcessor nextProcessor) {
    this.rmContext = (RMContext)amsContext;
  }

  @Override
  public void registerApplicationMaster(
      ApplicationAttemptId applicationAttemptId,
      RegisterApplicationMasterRequest request,
      RegisterApplicationMasterResponse response) throws IOException {

    RMApp app = getRmContext().getRMApps().get(
        applicationAttemptId.getApplicationId());
    LOG.info("AM registration " + applicationAttemptId);
    getRmContext().getDispatcher().getEventHandler()
        .handle(
            new RMAppAttemptRegistrationEvent(applicationAttemptId, request
                .getHost(), request.getRpcPort(), request.getTrackingUrl()));
    RMAuditLogger.logSuccess(app.getUser(),
        RMAuditLogger.AuditConstants.REGISTER_AM,
        "ApplicationMasterService", app.getApplicationId(),
        applicationAttemptId);
    response.setMaximumResourceCapability(getScheduler()
        .getMaximumResourceCapability(app.getQueue()));
    response.setApplicationACLs(app.getRMAppAttempt(applicationAttemptId)
        .getSubmissionContext().getAMContainerSpec().getApplicationACLs());
    response.setQueue(app.getQueue());
    if (UserGroupInformation.isSecurityEnabled()) {
      LOG.info("Setting client token master key");
      response.setClientToAMTokenMasterKey(java.nio.ByteBuffer.wrap(
          getRmContext().getClientToAMTokenSecretManager()
          .getMasterKey(applicationAttemptId).getEncoded()));
    }

    // For work-preserving AM restart, retrieve previous attempts' containers
    // and corresponding NM tokens.
    if (app.getApplicationSubmissionContext()
        .getKeepContainersAcrossApplicationAttempts()) {
      List<Container> transferredContainers = getScheduler()
          .getTransferredContainers(applicationAttemptId);
      if (!transferredContainers.isEmpty()) {
        response.setContainersFromPreviousAttempts(transferredContainers);
        // Clear the node set remembered by the secret manager. Necessary
        // for UAM restart because we use the same attemptId.
        rmContext.getNMTokenSecretManager()
            .clearNodeSetForAttempt(applicationAttemptId);

        List<NMToken> nmTokens = new ArrayList<NMToken>();
        for (Container container : transferredContainers) {
          try {
            NMToken token = getRmContext().getNMTokenSecretManager()
                .createAndGetNMToken(app.getUser(), applicationAttemptId,
                    container);
            if (null != token) {
              nmTokens.add(token);
            }
          } catch (IllegalArgumentException e) {
            // if it's a DNS issue, throw UnknowHostException directly and
            // that
            // will be automatically retried by RMProxy in RPC layer.
            if (e.getCause() instanceof UnknownHostException) {
              throw (UnknownHostException) e.getCause();
            }
          }
        }
        response.setNMTokensFromPreviousAttempts(nmTokens);
        LOG.info("Application " + app.getApplicationId() + " retrieved "
            + transferredContainers.size() + " containers from previous"
            + " attempts and " + nmTokens.size() + " NM tokens.");
      }
    }

    response.setSchedulerResourceTypes(getScheduler()
        .getSchedulingResourceTypes());
  }

  @Override
  public void allocate(ApplicationAttemptId appAttemptId,
      AllocateRequest request, AllocateResponse response) throws YarnException {

    handleProgress(appAttemptId, request);

    List<ResourceRequest> ask = request.getAskList();
    List<ContainerId> release = request.getReleaseList();

    ResourceBlacklistRequest blacklistRequest =
        request.getResourceBlacklistRequest();
    List<String> blacklistAdditions =
        (blacklistRequest != null) ?
            blacklistRequest.getBlacklistAdditions() : Collections.EMPTY_LIST;
    List<String> blacklistRemovals =
        (blacklistRequest != null) ?
            blacklistRequest.getBlacklistRemovals() : Collections.EMPTY_LIST;
    RMApp app =
        getRmContext().getRMApps().get(appAttemptId.getApplicationId());

    // set label expression for Resource Requests if resourceName=ANY
    ApplicationSubmissionContext asc = app.getApplicationSubmissionContext();
    for (ResourceRequest req : ask) {
      if (null == req.getNodeLabelExpression()
          && ResourceRequest.ANY.equals(req.getResourceName())) {
        req.setNodeLabelExpression(asc.getNodeLabelExpression());
      }
    }

    Resource maximumCapacity = getScheduler().getMaximumResourceCapability();

    // sanity check
    try {
      RMServerUtils.normalizeAndValidateRequests(ask,
          maximumCapacity, app.getQueue(),
          getScheduler(), getRmContext());
    } catch (InvalidResourceRequestException e) {
      LOG.warn("Invalid resource ask by application " + appAttemptId, e);
      throw e;
    }

    try {
      RMServerUtils.validateBlacklistRequest(blacklistRequest);
    }  catch (InvalidResourceBlacklistRequestException e) {
      LOG.warn("Invalid blacklist request by application " + appAttemptId, e);
      throw e;
    }

    // In the case of work-preserving AM restart, it's possible for the
    // AM to release containers from the earlier attempt.
    if (!app.getApplicationSubmissionContext()
        .getKeepContainersAcrossApplicationAttempts()) {
      try {
        RMServerUtils.validateContainerReleaseRequest(release, appAttemptId);
      } catch (InvalidContainerReleaseException e) {
        LOG.warn("Invalid container release by application " + appAttemptId,
            e);
        throw e;
      }
    }

    // Split Update Resource Requests into increase and decrease.
    // No Exceptions are thrown here. All update errors are aggregated
    // and returned to the AM.
    List<UpdateContainerError> updateErrors = new ArrayList<>();
    ContainerUpdates containerUpdateRequests =
        RMServerUtils.validateAndSplitUpdateResourceRequests(
            getRmContext(), request, maximumCapacity, updateErrors);

    // Send new requests to appAttempt.
    Allocation allocation;
    RMAppAttemptState state =
        app.getRMAppAttempt(appAttemptId).getAppAttemptState();
    if (state.equals(RMAppAttemptState.FINAL_SAVING) ||
        state.equals(RMAppAttemptState.FINISHING) ||
        app.isAppFinalStateStored()) {
      LOG.warn(appAttemptId + " is in " + state +
          " state, ignore container allocate request.");
      allocation = EMPTY_ALLOCATION;
    } else {
      allocation =
          getScheduler().allocate(appAttemptId, ask, release,
              blacklistAdditions, blacklistRemovals,
              containerUpdateRequests);
    }

    if (!blacklistAdditions.isEmpty() || !blacklistRemovals.isEmpty()) {
      LOG.info("blacklist are updated in Scheduler." +
          "blacklistAdditions: " + blacklistAdditions + ", " +
          "blacklistRemovals: " + blacklistRemovals);
    }
    RMAppAttempt appAttempt = app.getRMAppAttempt(appAttemptId);

    if (allocation.getNMTokens() != null &&
        !allocation.getNMTokens().isEmpty()) {
      response.setNMTokens(allocation.getNMTokens());
    }

    // Notify the AM of container update errors
    ApplicationMasterServiceUtils.addToUpdateContainerErrors(
        response, updateErrors);

    // update the response with the deltas of node status changes
    handleNodeUpdates(app, response);

    ApplicationMasterServiceUtils.addToAllocatedContainers(
        response, allocation.getContainers());

    response.setCompletedContainersStatuses(appAttempt
        .pullJustFinishedContainers());
    response.setAvailableResources(allocation.getResourceLimit());

    addToContainerUpdates(response, allocation,
        ((AbstractYarnScheduler)getScheduler())
            .getApplicationAttempt(appAttemptId).pullUpdateContainerErrors());

    response.setNumClusterNodes(getScheduler().getNumClusterNodes());

    // add collector address for this application
    if (YarnConfiguration.timelineServiceV2Enabled(
        getRmContext().getYarnConfiguration())) {
      CollectorInfo collectorInfo = app.getCollectorInfo();
      if (collectorInfo != null) {
        response.setCollectorInfo(collectorInfo);
      }
    }

    // add preemption to the allocateResponse message (if any)
    response.setPreemptionMessage(generatePreemptionMessage(allocation));

    // Set application priority
    response.setApplicationPriority(app
        .getApplicationPriority());
  }

  private void handleNodeUpdates(RMApp app, AllocateResponse allocateResponse) {
    List<RMNode> updatedNodes = new ArrayList<>();
    if(app.pullRMNodeUpdates(updatedNodes) > 0) {
      List<NodeReport> updatedNodeReports = new ArrayList<>();
      for(RMNode rmNode: updatedNodes) {
        SchedulerNodeReport schedulerNodeReport =
            getScheduler().getNodeReport(rmNode.getNodeID());
        Resource used = BuilderUtils.newResource(0, 0);
        int numContainers = 0;
        if (schedulerNodeReport != null) {
          used = schedulerNodeReport.getUsedResource();
          numContainers = schedulerNodeReport.getNumContainers();
        }
        NodeId nodeId = rmNode.getNodeID();
        NodeReport report =
            BuilderUtils.newNodeReport(nodeId, rmNode.getState(),
                rmNode.getHttpAddress(), rmNode.getRackName(), used,
                rmNode.getTotalCapability(), numContainers,
                rmNode.getHealthReport(), rmNode.getLastHealthReportTime(),
                rmNode.getNodeLabels());

        updatedNodeReports.add(report);
      }
      allocateResponse.setUpdatedNodes(updatedNodeReports);
    }
  }

  private void handleProgress(ApplicationAttemptId appAttemptId,
      AllocateRequest request) {
    //filter illegal progress values
    float filteredProgress = request.getProgress();
    if (Float.isNaN(filteredProgress) ||
        filteredProgress == Float.NEGATIVE_INFINITY ||
        filteredProgress < 0) {
      request.setProgress(0);
    } else if (filteredProgress > 1 ||
        filteredProgress == Float.POSITIVE_INFINITY) {
      request.setProgress(1);
    }

    // Send the status update to the appAttempt.
    getRmContext().getDispatcher().getEventHandler().handle(
        new RMAppAttemptStatusupdateEvent(appAttemptId, request
            .getProgress()));
  }

  @Override
  public void finishApplicationMaster(
      ApplicationAttemptId applicationAttemptId,
      FinishApplicationMasterRequest request,
      FinishApplicationMasterResponse response) {
    RMApp app =
        getRmContext().getRMApps().get(applicationAttemptId.getApplicationId());
    // For UnmanagedAMs, return true so they don't retry
    response.setIsUnregistered(
            app.getApplicationSubmissionContext().getUnmanagedAM());
    getRmContext().getDispatcher().getEventHandler().handle(
        new RMAppAttemptUnregistrationEvent(applicationAttemptId, request
            .getTrackingUrl(), request.getFinalApplicationStatus(), request
            .getDiagnostics()));
  }

  private PreemptionMessage generatePreemptionMessage(Allocation allocation){
    PreemptionMessage pMsg = null;
    // assemble strict preemption request
    if (allocation.getStrictContainerPreemptions() != null) {
      pMsg =
          recordFactory.newRecordInstance(PreemptionMessage.class);
      StrictPreemptionContract pStrict =
          recordFactory.newRecordInstance(StrictPreemptionContract.class);
      Set<PreemptionContainer> pCont = new HashSet<>();
      for (ContainerId cId : allocation.getStrictContainerPreemptions()) {
        PreemptionContainer pc =
            recordFactory.newRecordInstance(PreemptionContainer.class);
        pc.setId(cId);
        pCont.add(pc);
      }
      pStrict.setContainers(pCont);
      pMsg.setStrictContract(pStrict);
    }

    // assemble negotiable preemption request
    if (allocation.getResourcePreemptions() != null &&
        allocation.getResourcePreemptions().size() > 0 &&
        allocation.getContainerPreemptions() != null &&
        allocation.getContainerPreemptions().size() > 0) {
      if (pMsg == null) {
        pMsg =
            recordFactory.newRecordInstance(PreemptionMessage.class);
      }
      PreemptionContract contract =
          recordFactory.newRecordInstance(PreemptionContract.class);
      Set<PreemptionContainer> pCont = new HashSet<>();
      for (ContainerId cId : allocation.getContainerPreemptions()) {
        PreemptionContainer pc =
            recordFactory.newRecordInstance(PreemptionContainer.class);
        pc.setId(cId);
        pCont.add(pc);
      }
      List<PreemptionResourceRequest> pRes = new ArrayList<>();
      for (ResourceRequest crr : allocation.getResourcePreemptions()) {
        PreemptionResourceRequest prr =
            recordFactory.newRecordInstance(PreemptionResourceRequest.class);
        prr.setResourceRequest(crr);
        pRes.add(prr);
      }
      contract.setContainers(pCont);
      contract.setResourceRequest(pRes);
      pMsg.setContract(contract);
    }

    return pMsg;
  }

  protected RMContext getRmContext() {
    return rmContext;
  }

  protected YarnScheduler getScheduler() {
    return rmContext.getScheduler();
  }

  private static void addToContainerUpdates(AllocateResponse allocateResponse,
      Allocation allocation, List<UpdateContainerError> updateContainerErrors) {
    // Handling increased containers
    ApplicationMasterServiceUtils.addToUpdatedContainers(
        allocateResponse, ContainerUpdateType.INCREASE_RESOURCE,
        allocation.getIncreasedContainers());

    // Handling decreased containers
    ApplicationMasterServiceUtils.addToUpdatedContainers(
        allocateResponse, ContainerUpdateType.DECREASE_RESOURCE,
        allocation.getDecreasedContainers());

    // Handling promoted containers
    ApplicationMasterServiceUtils.addToUpdatedContainers(
        allocateResponse, ContainerUpdateType.PROMOTE_EXECUTION_TYPE,
        allocation.getPromotedContainers());

    // Handling demoted containers
    ApplicationMasterServiceUtils.addToUpdatedContainers(
        allocateResponse, ContainerUpdateType.DEMOTE_EXECUTION_TYPE,
        allocation.getDemotedContainers());

    ApplicationMasterServiceUtils.addToUpdateContainerErrors(
        allocateResponse, updateContainerErrors);
  }
}