/**
*
* 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.hbase.master.handler;
import java.io.IOException;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.TableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.Server;
import org.apache.hadoop.hbase.MetaTableAccessor;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.client.TableState;
import org.apache.hadoop.hbase.executor.EventType;
import org.apache.hadoop.hbase.master.HMaster;
import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
import org.apache.hadoop.hbase.master.MasterFileSystem;
import org.apache.hadoop.hbase.master.MasterServices;
import org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos;
import org.apache.hadoop.hbase.util.Bytes;
@InterfaceAudience.Private
public class ModifyTableHandler extends TableEventHandler {
private static final Log LOG = LogFactory.getLog(ModifyTableHandler.class);
private final HTableDescriptor htd;
public ModifyTableHandler(final TableName tableName,
final HTableDescriptor htd, final Server server,
final MasterServices masterServices) {
super(EventType.C_M_MODIFY_TABLE, tableName, server, masterServices);
// This is the new schema we are going to write out as this modification.
this.htd = htd;
}
@Override
protected void prepareWithTableLock() throws IOException {
super.prepareWithTableLock();
// Check operation is possible on the table in its current state
// Also checks whether the table exists
if (masterServices.getAssignmentManager().getTableStateManager()
.isTableState(this.htd.getTableName(), TableState.State.ENABLED)
&& this.htd.getRegionReplication() != getTableDescriptor()
.getHTableDescriptor().getRegionReplication()) {
throw new IOException("REGION_REPLICATION change is not supported for enabled tables");
}
}
@Override
protected void handleTableOperation(List<HRegionInfo> hris)
throws IOException {
MasterCoprocessorHost cpHost = ((HMaster) this.server).getMasterCoprocessorHost();
if (cpHost != null) {
cpHost.preModifyTableHandler(this.tableName, this.htd);
}
// Update descriptor
HTableDescriptor oldDescriptor =
this.masterServices.getTableDescriptors().get(this.tableName);
this.masterServices.getTableDescriptors().add(htd);
deleteFamilyFromFS(hris, oldDescriptor.getFamiliesKeys());
removeReplicaColumnsIfNeeded(
this.htd.getRegionReplication(),
oldDescriptor.getRegionReplication(),
this.htd.getTableName());
if (cpHost != null) {
cpHost.postModifyTableHandler(this.tableName, this.htd);
}
}
private void removeReplicaColumnsIfNeeded(int newReplicaCount, int oldReplicaCount,
TableName table) throws IOException {
if (newReplicaCount >= oldReplicaCount) return;
Set<byte[]> tableRows = new HashSet<byte[]>();
Scan scan = MetaTableAccessor.getScanForTableName(table);
scan.addColumn(HConstants.CATALOG_FAMILY, HConstants.REGIONINFO_QUALIFIER);
Table htable = null;
try {
htable = new HTable(masterServices.getConfiguration(), TableName.META_TABLE_NAME);
ResultScanner resScanner = htable.getScanner(scan);
for (Result result : resScanner) {
tableRows.add(result.getRow());
}
MetaTableAccessor.removeRegionReplicasFromMeta(tableRows, newReplicaCount,
oldReplicaCount - newReplicaCount, masterServices.getShortCircuitConnection());
} finally {
if (htable != null) {
htable.close();
}
}
}
/**
* Removes from hdfs the families that are not longer present in the new table descriptor.
*/
private void deleteFamilyFromFS(final List<HRegionInfo> hris, final Set<byte[]> oldFamilies) {
try {
Set<byte[]> newFamilies = this.htd.getFamiliesKeys();
MasterFileSystem mfs = this.masterServices.getMasterFileSystem();
for (byte[] familyName: oldFamilies) {
if (!newFamilies.contains(familyName)) {
LOG.debug("Removing family=" + Bytes.toString(familyName) +
" from table=" + this.tableName);
for (HRegionInfo hri: hris) {
// Delete the family directory in FS for all the regions one by one
mfs.deleteFamilyFromFS(hri, familyName);
}
}
}
} catch (IOException e) {
LOG.warn("Unable to remove on-disk directories for the removed families", e);
}
}
@Override
public String toString() {
String name = "UnknownServerName";
if(server != null && server.getServerName() != null) {
name = server.getServerName().toString();
}
return getClass().getSimpleName() + "-" + name + "-" + getSeqid() + "-" +
tableName;
}
}