hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/container/replication/health/OpenContainerHandler.java

/*
 * 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.hdds.scm.container.replication.health;

import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
import org.apache.hadoop.hdds.scm.container.ContainerInfo;
import org.apache.hadoop.hdds.scm.container.ContainerReplica;
import org.apache.hadoop.hdds.scm.container.ReplicationManagerReport;
import org.apache.hadoop.hdds.scm.container.replication.ContainerCheckRequest;
import org.apache.hadoop.hdds.scm.container.replication.ReplicationManager;

import java.util.Set;

import static org.apache.hadoop.hdds.scm.container.replication.ReplicationManager.compareState;

/**
 * Class used in Replication Manager to check open container health for both
 * EC and Ratis containers. Healthy open containers are skipped, while
 * containers where some replicas are not in the same state as the container
 * will be closed.
 */
public class OpenContainerHandler extends AbstractCheck {

  private ReplicationManager replicationManager;

  public OpenContainerHandler(ReplicationManager replicationManager) {
    this.replicationManager = replicationManager;
  }

  @Override
  public boolean handle(ContainerCheckRequest request) {
    ContainerInfo containerInfo = request.getContainerInfo();
    if (containerInfo.getState() == HddsProtos.LifeCycleState.OPEN) {
      if (!isOpenContainerHealthy(
          containerInfo, request.getContainerReplicas())) {
        // This is an unhealthy open container, so we need to trigger the
        // close process on it.
        request.getReport().incrementAndSample(
            ReplicationManagerReport.HealthState.OPEN_UNHEALTHY,
            containerInfo.containerID());
        replicationManager.sendCloseContainerEvent(containerInfo.containerID());
        return true;
      }
      // For open containers we do not want to do any further processing in RM
      // so return true to stop the command chain.
      return true;
    }
    // The container is not open, so we return false to let the next handler in
    // the chain process it.
    return false;
  }

  /**
   * An open container is healthy if all its replicas are in the same state as
   * the container.
   * @param container The container to check
   * @param replicas The replicas belonging to the container
   * @return True if the container is healthy, false otherwise
   */
  private boolean isOpenContainerHealthy(
      ContainerInfo container, Set< ContainerReplica > replicas) {
    HddsProtos.LifeCycleState state = container.getState();
    return replicas.stream()
        .allMatch(r -> compareState(state, r.getState()));
  }
}