/**
* 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 com.alibaba.wasp.master.handler;
import com.alibaba.wasp.EntityGroupInfo;
import com.alibaba.wasp.Server;
import com.alibaba.wasp.ServerName;
import com.alibaba.wasp.TableExistsException;
import com.alibaba.wasp.TableLockedException;
import com.alibaba.wasp.executor.EventHandler;
import com.alibaba.wasp.master.AssignmentManager;
import com.alibaba.wasp.master.FMasterServices;
import com.alibaba.wasp.master.FServerManager;
import com.alibaba.wasp.master.TableLockManager;
import com.alibaba.wasp.meta.FMetaEditor;
import com.alibaba.wasp.meta.FMetaReader;
import com.alibaba.wasp.meta.FTable;
import com.google.protobuf.ServiceException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.zookeeper.KeeperException;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
/**
* Handler to create a table.
*/
public class CreateTableHandler extends EventHandler {
private static final Log LOG = LogFactory.getLog(CreateTableHandler.class);
private final AssignmentManager assignmentManager;
private final FTable table;
private EntityGroupInfo[] newEntityGroups;
private final Configuration conf;
private TableLockManager tableLockManager;
public CreateTableHandler(Server server, FMasterServices fMasterServices,
AssignmentManager assignmentManager, FTable table,
EntityGroupInfo[] newEntityGroups) throws TableExistsException,
IOException {
super(server, EventType.C_M_CREATE_TABLE);
this.table = table;
this.newEntityGroups = newEntityGroups;
this.assignmentManager = assignmentManager;
String tableName = this.table.getTableName();
this.conf = server.getConfiguration();
// Check if table exists
if (FMetaReader.tableExists(conf, tableName)) {
throw new TableExistsException(tableName);
}
// If we have multiple client threads trying to create the table at the
// same time, given the async nature of the operation, the table
// could be in a state where .META. table hasn't been updated yet in
// the process() function.
// Use enabling state to tell if there is already a request for the same
// table in progress. This will introduce a new zookeeper call. Given
// createTable isn't a frequent operation, that should be ok.
try {
this.tableLockManager = fMasterServices.getTableLockManager();
if (tableLockManager.lockTable(tableName)) {
LOG.info("lock table '" + tableName + "' by CreateIndexHandler");
} else {
throw new TableLockedException(tableName + " has been locked. ");
}
try {
if (!this.assignmentManager.getZKTable().checkAndSetEnablingTable(
tableName))
throw new TableExistsException(tableName);
} catch (KeeperException e) {
tableLockManager.unlockTable(tableName);
throw new IOException("Unable to ensure that the table will be"
+ " enabling because of a ZooKeeper issue", e);
}
} catch (TableExistsException e) {
tableLockManager.unlockTable(tableName);
throw e;
}
}
@Override
public void process() throws IOException {
String tableName = this.table.getTableName();
try {
LOG.info("Attempting to create the table " + tableName);
handleCreateTable(tableName);
} catch (IOException e) {
LOG.error("Error trying to create the table " + tableName, e);
} catch (ServiceException e) {
LOG.error("Error trying to create the table " + tableName, e);
} finally {
tableLockManager.unlockTable(tableName);
}
}
private void handleCreateTable(String tableName) throws IOException,
ServiceException {
// 1. Add Table Info to FMETA
FMetaEditor.createTable(this.conf, table);
// 2. Add Table's EntityGroupInfos to FMETA
List<EntityGroupInfo> entityGroupInfos = Arrays.asList(newEntityGroups);
if (entityGroupInfos.size() > 0) {
FMetaEditor.addEntityGroupsToMeta(this.conf, entityGroupInfos);
}
// 3. Trigger immediate assignment of the entityGroups in round-robin
// fashion
try {
List<EntityGroupInfo> entityGroups = Arrays.asList(newEntityGroups);
if (entityGroups.size() > 0) {
assignmentManager.getEntityGroupStates().createEntityGroupStates(
entityGroups);
assignmentManager.assign(entityGroups);
}
} catch (InterruptedException ie) {
LOG.error("Caught " + ie + " during round-robin assignment");
throw new IOException(ie);
}
// 4. Set table enabled flag up in zk.
try {
// notify server to refresh the table's meta cache.
FServerManager serverManager = ((FMasterServices) server)
.getFServerManager();
for (ServerName serverName : serverManager.getOnlineServersList()) {
serverManager.sendEnableTable(serverName, tableName);
}
assignmentManager.getZKTable().setEnabledTable(this.table.getTableName());
} catch (KeeperException e) {
throw new IOException("Unable to ensure that the table will be"
+ " enabled because of a ZooKeeper issue", e);
}
}
@Override
public String toString() {
String name = "UnknownServerName";
if (server != null && server.getServerName() != null) {
name = server.getServerName().toString();
}
return getClass().getSimpleName() + "-" + name + "-" + getSeqid() + "-"
+ this.table.getTableName();
}
}