| /** |
| * 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<InetSocketAddress> getIncludes(); |
| |
| /** |
| * Return all datanodes that should be in decommissioned state. |
| * @return Iterable of those datanodes |
| */ |
| public abstract Iterable<InetSocketAddress> 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); |
| } |