storm 消息确认机制及可靠性

worker进程死掉

在一个节点 kill work进程 比方 kill 2509  对work没有影响 由于会在其它节点又一次启动进程运行topology任务

supervisor进程死掉

supervisor进程kill掉 对work进程没有影响  由于他们是互相独立的！

。

nimbus进程死掉(存在HA的问题)

nimbus假设死掉 整个任务挂掉 存在单点故障问题！(hadoop2有ha！。！！。！

storm没有ha高可用)

节点宕机(和supervisor是一样的)

ack/fail消息确认机制

spout发送过来的数据  blot要确认数据是否收到及反馈给spout 以下给一个样例：

import java.util.Map;

import backtype.storm.Config;

import backtype.storm.StormSubmitter;

import backtype.storm.generated.AlreadyAliveException;

import backtype.storm.generated.InvalidTopologyException;

import backtype.storm.spout.SpoutOutputCollector;

import backtype.storm.task.OutputCollector;

import backtype.storm.task.TopologyContext;

import backtype.storm.topology.OutputFieldsDeclarer;

import backtype.storm.topology.TopologyBuilder;

import backtype.storm.topology.base.BaseRichBolt;

import backtype.storm.topology.base.BaseRichSpout;

import backtype.storm.tuple.Fields;

import backtype.storm.tuple.Tuple;

import backtype.storm.tuple.Values;

import backtype.storm.utils.Utils;





public class ClusterStormTopologyAck {



public static class DataSourceSpout extends BaseRichSpout{

private Map conf;

private TopologyContext context;

private SpoutOutputCollector collector;



/**

* 在本实例执行的时候被调用一次

*/

public void open(Map conf, TopologyContext context,

SpoutOutputCollector collector) {

this.conf = conf;

this.context = context;

this.collector = collector;

}

/**

* 死循环调用 心跳

*/

int i=0;

public void nextTuple() {

System.err.println("spout :"+i);

//values 就是value的list列表

//(new Values(i++),i-1);发送的值及key一一相应

this.collector.emit(new Values(i++),i-1);

Utils.sleep(1000);

}

/**

* 声明字段名称

*/

public void declareOutputFields(OutputFieldsDeclarer declarer) {

//fields就是field的列表

declarer.declare(new Fields("num"));

}

@Override

public void ack(Object msgId) {

System.out.println("运行ACK："+msgId);

}

@Override

public void fail(Object msgId) {

System.out.println("运行FAIL："+msgId);

//TODO--

//this.collector.emit(tuple);

}





}



public static class SumBolt extends BaseRichBolt{



private Map stormConf;

private TopologyContext context;

private OutputCollector collector;

/**

* 仅仅会被调用一次

*/

public void prepare(Map stormConf, TopologyContext context,

OutputCollector collector) {

this.stormConf = stormConf;

this.context = context;

this.collector = collector;

}

/**

* 死循环，循环的获取上一级发送过来的数据（spout/bolt）

*/

int sum = 0;

public void execute(Tuple input) {

//input.getInteger(0);

Integer count = input.getIntegerByField("num");



try{

//--------



this.collector.ack(input);

}catch(Exception e){

this.collector.fail(input);

}

/*if(count>10 && count<20){

this.collector.fail(input);

}{

this.collector.ack(input);

}*/

}





public void declareOutputFields(OutputFieldsDeclarer declarer) {



}

}





public static void main(String[] args) {

TopologyBuilder builder = new TopologyBuilder();

String SPOUT_NAME = DataSourceSpout.class.getSimpleName();

String BOLT_NAME = SumBolt.class.getSimpleName();

builder.setSpout(SPOUT_NAME, new DataSourceSpout());

builder.setBolt(BOLT_NAME, new SumBolt()).shuffleGrouping(SPOUT_NAME);

Config config = new Config();

try {

StormSubmitter.submitTopology(ClusterStormTopologyAck.class.getSimpleName(), config, builder.createTopology());

} catch (AlreadyAliveException e) {

e.printStackTrace();

} catch (InvalidTopologyException e) {

e.printStackTrace();

}





}





}