/**
* 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.snapshot;
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.classification.InterfaceAudience;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.errorhandling.ForeignException;
import org.apache.hadoop.hbase.exceptions.HBaseSnapshotException;
import org.apache.hadoop.hbase.master.MasterServices;
import org.apache.hadoop.hbase.procedure.Procedure;
import org.apache.hadoop.hbase.procedure.ProcedureCoordinator;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription;
import org.apache.hadoop.hbase.util.Pair;
import com.google.common.collect.Lists;
/**
* Handle the master side of taking a snapshot of an online table, regardless of snapshot type.
* Uses a {@link Procedure} to run the snapshot across all the involved region servers.
* @see ProcedureCoordinator
*/
@InterfaceAudience.Private
public class EnabledTableSnapshotHandler extends TakeSnapshotHandler {
private static final Log LOG = LogFactory.getLog(EnabledTableSnapshotHandler.class);
private final ProcedureCoordinator coordinator;
public EnabledTableSnapshotHandler(SnapshotDescription snapshot, MasterServices master,
SnapshotManager manager) throws IOException {
super(snapshot, master);
this.coordinator = manager.getCoordinator();
}
@Override
public EnabledTableSnapshotHandler prepare() throws Exception {
return (EnabledTableSnapshotHandler) super.prepare();
}
// TODO consider switching over to using regionnames, rather than server names. This would allow
// regions to migrate during a snapshot, and then be involved when they are ready. Still want to
// enforce a snapshot time constraints, but lets us be potentially a bit more robust.
/**
* This method kicks off a snapshot procedure. Other than that it hangs around for various
* phases to complete.
*/
@Override
protected void snapshotRegions(List<Pair<HRegionInfo, ServerName>> regions)
throws HBaseSnapshotException {
Set<String> regionServers = new HashSet<String>(regions.size());
for (Pair<HRegionInfo, ServerName> region : regions) {
regionServers.add(region.getSecond().toString());
}
// start the snapshot on the RS
Procedure proc = coordinator.startProcedure(this.monitor, this.snapshot.getName(),
this.snapshot.toByteArray(), Lists.newArrayList(regionServers));
if (proc == null) {
String msg = "Failed to submit distributed procedure for snapshot '"
+ snapshot.getName() + "'";
LOG.error(msg);
throw new HBaseSnapshotException(msg);
}
try {
// wait for the snapshot to complete. A timer thread is kicked off that should cancel this
// if it takes too long.
proc.waitForCompleted();
LOG.info("Done waiting - snapshot for " + this.snapshot.getName() + " finished!");
} catch (InterruptedException e) {
ForeignException ee =
new ForeignException("Interrupted while waiting for snapshot to finish", e);
monitor.receive(ee);
Thread.currentThread().interrupt();
} catch (ForeignException e) {
monitor.receive(e);
}
}
}