package org.apache.helix.examples;
/*
* 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.
*/
import java.io.File;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Date;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.GnuParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.OptionBuilder;
import org.apache.commons.cli.OptionGroup;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.helix.HelixManager;
import org.apache.helix.HelixManagerFactory;
import org.apache.helix.InstanceType;
import org.apache.helix.NotificationContext;
import org.apache.helix.messaging.AsyncCallback;
import org.apache.helix.messaging.handling.HelixTaskResult;
import org.apache.helix.messaging.handling.MessageHandler;
import org.apache.helix.messaging.handling.MessageHandlerFactory;
import org.apache.helix.model.Message;
import org.apache.helix.model.Message.MessageType;
import org.apache.helix.participant.StateMachineEngine;
import org.apache.helix.participant.statemachine.StateModel;
import org.apache.helix.participant.statemachine.StateModelFactory;
import org.apache.helix.tools.ClusterStateVerifier;
/**
* This process does little more than handling the state transition messages.
* This is generally the case when the server needs to bootstrap when it comes
* up.<br>
* Flow for a typical Master-slave state model<br>
* <ul>
* <li>Gets OFFLINE-SLAVE transition</li>
* <li>Figure out if it has any data and how old it is for the SLAVE partition</li>
* <li>If the data is fresh enough it can probably catch up from the replication
* stream of the master</li>
* <li>If not, then it can use the messaging service provided by cluster manager
* to talk other nodes to figure out if they have any backup</li>
* </li>
* <li>Once it gets a response from other nodes in the cluster the process can
* decide which back up it wants to use to bootstrap</li>
* </ul>
*
*/
public class BootstrapProcess
{
static final String REQUEST_BOOTSTRAP_URL = "REQUEST_BOOTSTRAP_URL";
public static final String zkServer = "zkSvr";
public static final String cluster = "cluster";
public static final String hostAddress = "host";
public static final String hostPort = "port";
public static final String relayCluster = "relayCluster";
public static final String help = "help";
public static final String configFile = "configFile";
public static final String stateModel = "stateModelType";
public static final String transDelay = "transDelay";
private final String zkConnectString;
private final String clusterName;
private final String instanceName;
private final String stateModelType;
private HelixManager manager;
// private StateMachineEngine genericStateMachineHandler;
private String _file = null;
private StateModelFactory<StateModel> stateModelFactory;
private final int delay;
public BootstrapProcess(String zkConnectString, String clusterName,
String instanceName, String stateModel, int delay)
{
this.zkConnectString = zkConnectString;
this.clusterName = clusterName;
this.instanceName = instanceName;
stateModelType = stateModel;
this.delay = delay;
}
public void start() throws Exception
{
manager = HelixManagerFactory.getZKHelixManager(clusterName,
instanceName,
InstanceType.PARTICIPANT,
zkConnectString);
stateModelFactory = new BootstrapHandler();
// genericStateMachineHandler = new StateMachineEngine();
// genericStateMachineHandler.registerStateModelFactory("MasterSlave", stateModelFactory);
StateMachineEngine stateMach = manager.getStateMachineEngine();
stateMach.registerStateModelFactory("MasterSlave", stateModelFactory);
manager.getMessagingService().registerMessageHandlerFactory(
MessageType.STATE_TRANSITION.toString(), stateMach);
manager.getMessagingService().registerMessageHandlerFactory(
MessageType.USER_DEFINE_MSG.toString(),
new CustomMessageHandlerFactory());
manager.connect();
}
public static class CustomMessageHandlerFactory implements
MessageHandlerFactory
{
@Override
public MessageHandler createHandler(Message message,
NotificationContext context)
{
return new CustomMessageHandler(message, context);
}
@Override
public String getMessageType()
{
return MessageType.USER_DEFINE_MSG.toString();
}
@Override
public void reset()
{
}
static class CustomMessageHandler extends MessageHandler
{
public CustomMessageHandler(Message message, NotificationContext context)
{
super(message, context);
// TODO Auto-generated constructor stub
}
@Override
public HelixTaskResult handleMessage() throws InterruptedException
{
String hostName;
HelixTaskResult result = new HelixTaskResult();
try
{
hostName = InetAddress.getLocalHost().getCanonicalHostName();
} catch (UnknownHostException e)
{
hostName = "UNKNOWN";
}
String port = "2134";
String msgSubType = _message.getMsgSubType();
if (msgSubType.equals(REQUEST_BOOTSTRAP_URL))
{
result.getTaskResultMap().put(
"BOOTSTRAP_URL",
"http://" + hostName + ":" + port
+ "/getFile?path=/data/bootstrap/"
+ _message.getResourceName() + "/"
+ _message.getPartitionName() + ".tar");
result.getTaskResultMap().put(
"BOOTSTRAP_TIME",
""+new Date().getTime());
}
result.setSuccess(true);
return result;
}
@Override
public void onError( Exception e, ErrorCode code, ErrorType type)
{
e.printStackTrace();
}
}
}
@SuppressWarnings("static-access")
private static Options constructCommandLineOptions()
{
Option helpOption = OptionBuilder.withLongOpt(help)
.withDescription("Prints command-line options info").create();
Option zkServerOption = OptionBuilder.withLongOpt(zkServer)
.withDescription("Provide zookeeper address").create();
zkServerOption.setArgs(1);
zkServerOption.setRequired(true);
zkServerOption.setArgName("ZookeeperServerAddress(Required)");
Option clusterOption = OptionBuilder.withLongOpt(cluster)
.withDescription("Provide cluster name").create();
clusterOption.setArgs(1);
clusterOption.setRequired(true);
clusterOption.setArgName("Cluster name (Required)");
Option hostOption = OptionBuilder.withLongOpt(hostAddress)
.withDescription("Provide host name").create();
hostOption.setArgs(1);
hostOption.setRequired(true);
hostOption.setArgName("Host name (Required)");
Option portOption = OptionBuilder.withLongOpt(hostPort)
.withDescription("Provide host port").create();
portOption.setArgs(1);
portOption.setRequired(true);
portOption.setArgName("Host port (Required)");
Option stateModelOption = OptionBuilder.withLongOpt(stateModel)
.withDescription("StateModel Type").create();
stateModelOption.setArgs(1);
stateModelOption.setRequired(true);
stateModelOption.setArgName("StateModel Type (Required)");
// add an option group including either --zkSvr or --configFile
Option fileOption = OptionBuilder.withLongOpt(configFile)
.withDescription("Provide file to read states/messages").create();
fileOption.setArgs(1);
fileOption.setRequired(true);
fileOption.setArgName("File to read states/messages (Optional)");
Option transDelayOption = OptionBuilder.withLongOpt(transDelay)
.withDescription("Provide state trans delay").create();
transDelayOption.setArgs(1);
transDelayOption.setRequired(false);
transDelayOption.setArgName("Delay time in state transition, in MS");
OptionGroup optionGroup = new OptionGroup();
optionGroup.addOption(zkServerOption);
optionGroup.addOption(fileOption);
Options options = new Options();
options.addOption(helpOption);
// options.addOption(zkServerOption);
options.addOption(clusterOption);
options.addOption(hostOption);
options.addOption(portOption);
options.addOption(stateModelOption);
options.addOption(transDelayOption);
options.addOptionGroup(optionGroup);
return options;
}
public static void printUsage(Options cliOptions)
{
HelpFormatter helpFormatter = new HelpFormatter();
helpFormatter.printHelp("java " + BootstrapProcess.class.getName(), cliOptions);
}
public static CommandLine processCommandLineArgs(String[] cliArgs)
throws Exception
{
CommandLineParser cliParser = new GnuParser();
Options cliOptions = constructCommandLineOptions();
try
{
return cliParser.parse(cliOptions, cliArgs);
} catch (ParseException pe)
{
System.err
.println("CommandLineClient: failed to parse command-line options: "
+ pe.toString());
printUsage(cliOptions);
System.exit(1);
}
return null;
}
public static void main(String[] args) throws Exception
{
String zkConnectString = "localhost:2181";
String clusterName = "storage-integration-cluster";
String instanceName = "localhost_8905";
String stateModelValue = "MasterSlave";
int delay = 0;
boolean skipZeroArgs = true;// false is for dev testing
if (!skipZeroArgs || args.length > 0)
{
CommandLine cmd = processCommandLineArgs(args);
zkConnectString = cmd.getOptionValue(zkServer);
clusterName = cmd.getOptionValue(cluster);
String host = cmd.getOptionValue(hostAddress);
String portString = cmd.getOptionValue(hostPort);
int port = Integer.parseInt(portString);
instanceName = host + "_" + port;
stateModelValue = cmd.getOptionValue(stateModel);
if (cmd.hasOption(transDelay))
{
try
{
delay = Integer.parseInt(cmd.getOptionValue(transDelay));
if (delay < 0)
{
throw new Exception("delay must be positive");
}
} catch (Exception e)
{
e.printStackTrace();
delay = 0;
}
}
}
// Espresso_driver.py will consume this
System.out.println("Starting Process with ZK:" + zkConnectString);
BootstrapProcess process = new BootstrapProcess(zkConnectString,
clusterName, instanceName, stateModelValue, delay);
process.start();
Thread.currentThread().join();
}
}
class BootstrapReplyHandler extends AsyncCallback
{
public BootstrapReplyHandler()
{
}
private String bootstrapUrl;
private String bootstrapTime;
@Override
public void onTimeOut()
{
System.out.println("Timed out");
}
public String getBootstrapUrl()
{
return bootstrapUrl;
}
public String getBootstrapTime()
{
return bootstrapTime;
}
@Override
public void onReplyMessage(Message message)
{
String time = message.getResultMap().get("BOOTSTRAP_TIME");
if (bootstrapTime == null || time.compareTo(bootstrapTime) > -1)
{
bootstrapTime = message.getResultMap().get("BOOTSTRAP_TIME");
bootstrapUrl = message.getResultMap().get("BOOTSTRAP_URL");
}
}
}