org.apache.hadoop.hdfs.server.blockmanagement.HostConfigManager Maven / Gradle / Ivy
/**
* 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.server.blockmanagement;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.hdfs.protocol.DatanodeID;
import java.io.IOException;
import java.net.InetSocketAddress;
/**
* This interface abstracts how datanode configuration is managed.
*
* Each implementation defines its own way to persist the configuration.
* For example, it can use one JSON file to store the configs for all
* datanodes; or it can use one file to store in-service datanodes and another
* file to store decommission-requested datanodes.
*
* These files control which DataNodes the NameNode expects to see in the
* cluster.
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
public abstract class HostConfigManager implements Configurable {
/**
* Return all the datanodes that are allowed to connect to the namenode.
* @return Iterable of all datanodes
*/
public abstract Iterable getIncludes();
/**
* Return all datanodes that should be in decommissioned state.
* @return Iterable of those datanodes
*/
public abstract Iterable getExcludes();
/**
* Check if a datanode is allowed to connect the namenode.
* @param dn the DatanodeID of the datanode
* @return boolean if dn is allowed to connect the namenode.
*/
public abstract boolean isIncluded(DatanodeID dn);
/**
* Check if a datanode needs to be decommissioned.
* @param dn the DatanodeID of the datanode
* @return boolean if dn needs to be decommissioned.
*/
public abstract boolean isExcluded(DatanodeID dn);
/**
* Reload the configuration.
*/
public abstract void refresh() throws IOException;
/**
* Get the upgrade domain of a datanode.
* @param dn the DatanodeID of the datanode
* @return the upgrade domain of dn.
*/
public abstract String getUpgradeDomain(DatanodeID dn);
/**
* Get the maintenance expiration time in milli seconds.
* @param dn the DatanodeID of the datanode
* @return the maintenance expiration time of dn.
*/
public abstract long getMaintenanceExpirationTimeInMS(DatanodeID dn);
}