/**
*
* 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.List;
import java.util.concurrent.ExecutorService;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.CoordinatedStateException;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.Server;
import org.apache.hadoop.hbase.TableNotEnabledException;
import org.apache.hadoop.hbase.TableNotFoundException;
import org.apache.hadoop.hbase.MetaTableAccessor;
import org.apache.hadoop.hbase.constraint.ConstraintException;
import org.apache.hadoop.hbase.executor.EventHandler;
import org.apache.hadoop.hbase.executor.EventType;
import org.apache.hadoop.hbase.master.AssignmentManager;
import org.apache.hadoop.hbase.master.BulkAssigner;
import org.apache.hadoop.hbase.master.HMaster;
import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
import org.apache.hadoop.hbase.master.RegionStates;
import org.apache.hadoop.hbase.master.TableLockManager;
import org.apache.hadoop.hbase.master.RegionState.State;
import org.apache.hadoop.hbase.master.TableLockManager.TableLock;
import org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos;
import org.apache.htrace.Trace;
/**
* Handler to run disable of a table.
*/
@InterfaceAudience.Private
public class DisableTableHandler extends EventHandler {
private static final Log LOG = LogFactory.getLog(DisableTableHandler.class);
private final TableName tableName;
private final AssignmentManager assignmentManager;
private final TableLockManager tableLockManager;
private final boolean skipTableStateCheck;
private TableLock tableLock;
public DisableTableHandler(Server server, TableName tableName,
AssignmentManager assignmentManager, TableLockManager tableLockManager,
boolean skipTableStateCheck) {
super(server, EventType.C_M_DISABLE_TABLE);
this.tableName = tableName;
this.assignmentManager = assignmentManager;
this.tableLockManager = tableLockManager;
this.skipTableStateCheck = skipTableStateCheck;
}
public DisableTableHandler prepare()
throws TableNotFoundException, TableNotEnabledException, IOException {
if(tableName.equals(TableName.META_TABLE_NAME)) {
throw new ConstraintException("Cannot disable catalog table");
}
//acquire the table write lock, blocking
this.tableLock = this.tableLockManager.writeLock(tableName,
EventType.C_M_DISABLE_TABLE.toString());
this.tableLock.acquire();
boolean success = false;
try {
// Check if table exists
if (!MetaTableAccessor.tableExists(this.server.getConnection(), tableName)) {
throw new TableNotFoundException(tableName);
}
// There could be multiple client requests trying to disable or enable
// the table at the same time. Ensure only the first request is honored
// After that, no other requests can be accepted until the table reaches
// DISABLED or ENABLED.
//TODO: reevaluate this since we have table locks now
if (!skipTableStateCheck) {
try {
if (!this.assignmentManager.getTableStateManager().setTableStateIfInStates(
this.tableName, ZooKeeperProtos.Table.State.DISABLING,
ZooKeeperProtos.Table.State.ENABLED)) {
LOG.info("Table " + tableName + " isn't enabled; skipping disable");
throw new TableNotEnabledException(this.tableName);
}
} catch (CoordinatedStateException e) {
throw new IOException("Unable to ensure that the table will be" +
" disabling because of a coordination engine issue", e);
}
}
success = true;
} finally {
if (!success) {
releaseTableLock();
}
}
return this;
}
@Override
public String toString() {
String name = "UnknownServerName";
if(server != null && server.getServerName() != null) {
name = server.getServerName().toString();
}
return getClass().getSimpleName() + "-" + name + "-" + getSeqid() + "-" +
tableName;
}
@Override
public void process() {
try {
LOG.info("Attempting to disable table " + this.tableName);
MasterCoprocessorHost cpHost = ((HMaster) this.server)
.getMasterCoprocessorHost();
if (cpHost != null) {
cpHost.preDisableTableHandler(this.tableName);
}
handleDisableTable();
if (cpHost != null) {
cpHost.postDisableTableHandler(this.tableName);
}
} catch (IOException e) {
LOG.error("Error trying to disable table " + this.tableName, e);
} catch (CoordinatedStateException e) {
LOG.error("Error trying to disable table " + this.tableName, e);
} finally {
releaseTableLock();
}
}
private void releaseTableLock() {
if (this.tableLock != null) {
try {
this.tableLock.release();
} catch (IOException ex) {
LOG.warn("Could not release the table lock", ex);
}
}
}
private void handleDisableTable() throws IOException, CoordinatedStateException {
// Set table disabling flag up in zk.
this.assignmentManager.getTableStateManager().setTableState(this.tableName,
ZooKeeperProtos.Table.State.DISABLING);
boolean done = false;
while (true) {
// Get list of online regions that are of this table. Regions that are
// already closed will not be included in this list; i.e. the returned
// list is not ALL regions in a table, its all online regions according
// to the in-memory state on this master.
final List<HRegionInfo> regions = this.assignmentManager
.getRegionStates().getRegionsOfTable(tableName);
if (regions.size() == 0) {
done = true;
break;
}
LOG.info("Offlining " + regions.size() + " regions.");
BulkDisabler bd = new BulkDisabler(this.server, regions);
try {
if (bd.bulkAssign()) {
done = true;
break;
}
} catch (InterruptedException e) {
LOG.warn("Disable was interrupted");
// Preserve the interrupt.
Thread.currentThread().interrupt();
break;
}
}
// Flip the table to disabled if success.
if (done) this.assignmentManager.getTableStateManager().setTableState(this.tableName,
ZooKeeperProtos.Table.State.DISABLED);
LOG.info("Disabled table, " + this.tableName + ", is done=" + done);
}
/**
* Run bulk disable.
*/
class BulkDisabler extends BulkAssigner {
private final List<HRegionInfo> regions;
BulkDisabler(final Server server, final List<HRegionInfo> regions) {
super(server);
this.regions = regions;
}
@Override
protected void populatePool(ExecutorService pool) {
RegionStates regionStates = assignmentManager.getRegionStates();
for (HRegionInfo region: regions) {
if (regionStates.isRegionInTransition(region)
&& !regionStates.isRegionInState(region, State.FAILED_CLOSE)) {
continue;
}
final HRegionInfo hri = region;
pool.execute(Trace.wrap("DisableTableHandler.BulkDisabler",new Runnable() {
public void run() {
assignmentManager.unassign(hri, true);
}
}));
}
}
@Override
protected boolean waitUntilDone(long timeout)
throws InterruptedException {
long startTime = System.currentTimeMillis();
long remaining = timeout;
List<HRegionInfo> regions = null;
while (!server.isStopped() && remaining > 0) {
Thread.sleep(waitingTimeForEvents);
regions = assignmentManager.getRegionStates().getRegionsOfTable(tableName);
LOG.debug("Disable waiting until done; " + remaining + " ms remaining; " + regions);
if (regions.isEmpty()) break;
remaining = timeout - (System.currentTimeMillis() - startTime);
}
return regions != null && regions.isEmpty();
}
}
}