hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/ozone/protocol/commands/RetriableDatanodeEventWatcher.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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.protocol.commands;

import org.apache.hadoop.hdds.scm.command.CommandStatusReportHandler.CommandStatusEvent;
import org.apache.hadoop.hdds.scm.events.SCMEvents;
import org.apache.hadoop.hdds.server.events.Event;
import org.apache.hadoop.hdds.server.events.EventPublisher;
import org.apache.hadoop.hdds.server.events.EventWatcher;
import org.apache.hadoop.ozone.lease.LeaseManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * EventWatcher for start events and completion events with payload of type
 * RetriablePayload and RetriableCompletionPayload respectively.
 */
public class RetriableDatanodeEventWatcher<T extends CommandStatusEvent>
    extends EventWatcher<CommandForDatanode, T> {

  public static final Logger LOG =
      LoggerFactory.getLogger(RetriableDatanodeEventWatcher.class);

  public RetriableDatanodeEventWatcher(Event<CommandForDatanode> startEvent,
      Event<T> completionEvent, LeaseManager<Long> leaseManager) {
    super(startEvent, completionEvent, leaseManager);
  }

  @Override
  protected void onTimeout(EventPublisher publisher,
      CommandForDatanode payload) {
    LOG.info("RetriableDatanodeCommand type={} with id={} timed out. Retrying.",
        payload.getCommand().getType(), payload.getId());
    //put back to the original queue
    publisher.fireEvent(SCMEvents.RETRIABLE_DATANODE_COMMAND, payload);
  }

  @Override
  protected void onFinished(EventPublisher publisher,
      CommandForDatanode payload) {

  }
}