Storm-Kafka模块常用接口分析及使用Zk动态读取方式，storm-kafkazk

Storm-Kafka模块常用接口分析及使用Zk动态读取方式，storm-kafkazk

使用storm-kafka模块读取kafka中的数据，按照以下两步进行构建(我使用的版本是0.9.3) 1. 使用BrokerHosts接口来配置kafka broker host与partition的mapping信息; 2. 使用KafkaConfig来配置一些与kafka自身相关的选项，如fetchSizeBytes、socketTimeoutMs 下面分别介绍这两块的实现：
对于配置1，目前支持两种实现方式：zk配置、静态ip端口方式
第一种方式：Zk读取(比较常见)

ZkHosts支持两种创建方式，
public ZkHosts(String brokerZkStr, String brokerZkPath)
//使用默认brokerZkPath:"/brokers"
public ZkHosts(String brokerZkStr)

通过这种方式访问的时候，经过60s会刷新一下host->partition的mapping 第二步：构建KafkaConfig对象 目前提供两种构造函数，

public KafkaConfig(BrokerHosts hosts, String topic)
//clientId如果不想每次随机生成的话，就自己设置一个
public KafkaConfig(BrokerHosts hosts, String topic, String clientId)

代码参考：

        //这个地方其实就是kafka配置文件里边的zookeeper.connect这个参数，可以去那里拿过来。
        String brokerZkStr = "10.100.90.201:2181/kafka_online_sample";
        String brokerZkPath = "/brokers";
        ZkHosts zkHosts = new ZkHosts(brokerZkStr, brokerZkPath);

        String topic = "mars-wap";
        //以下：将offset汇报到哪个zk集群,相应配置
//        String offsetZkServers = "10.199.203.169";
        String offsetZkServers = "10.100.90.201";
        String offsetZkPort = "2181";
        List<String> zkServersList = new ArrayList<String>();
        zkServersList.add(offsetZkServers);
        //汇报offset信息的root路径
        String offsetZkRoot = "/stormExample";
        //存储该spout id的消费offset信息,譬如以topoName来命名
        String offsetZkId = "storm-example";


        SpoutConfig kafkaConfig = new SpoutConfig(zkHosts, topic, offsetZkRoot, offsetZkId);
        kafkaConfig.zkRoot = offsetZkRoot;
        kafkaConfig.zkPort = Integer.parseInt(offsetZkPort);
        kafkaConfig.zkServers = zkServersList;
        kafkaConfig.id = offsetZkId;
        kafkaConfig.scheme = new SchemeAsMultiScheme(new StringScheme());


        KafkaSpout spout = new KafkaSpout(kafkaConfig);

        TopologyBuilder builder = new TopologyBuilder();
        builder.setSpout("spout", spout, 1);
        builder.setBolt("bolt", new Bolt(), 1).shuffleGrouping("spout");

        Config config = new Config();

        LocalCluster cluster = new LocalCluster();
        cluster.submitTopology("test", config, builder.createTopology());

        // cluster submit.
//        try {
//            StormSubmitter.submitTopology("storm-kafka-example",config,builder.createTopology());
//        } catch (AlreadyAliveException e) {
//            e.printStackTrace();
//        } catch (InvalidTopologyException e) {
//            e.printStackTrace();
//        }

第二种方式：

String kafkaHost = "10.100.90.201";
        Broker brokerForPartition0 = new Broker(kafkaHost);//localhost:9092
        Broker brokerForPartition1 = new Broker(kafkaHost, 9092);//localhost:9092 but we specified the port explicitly
        GlobalPartitionInformation partitionInfo = new GlobalPartitionInformation();
        partitionInfo.addPartition(0, brokerForPartition0);//mapping form partition 0 to brokerForPartition0
        partitionInfo.addPartition(1, brokerForPartition1);//mapping form partition 1 to brokerForPartition1
        StaticHosts hosts = new StaticHosts(partitionInfo);

        String topic="mars-wap";
        String offsetZkRoot ="/stormExample";
        String offsetZkId="staticHost";
        String offsetZkServers = "10.100.90.201";
        String offsetZkPort = "2181";
        List<String> zkServersList = new ArrayList<String>();
        zkServersList.add(offsetZkServers);

        SpoutConfig kafkaConfig = new SpoutConfig(hosts,topic,offsetZkRoot,offsetZkId);

        kafkaConfig.zkPort = Integer.parseInt(offsetZkPort);
        kafkaConfig.zkServers = zkServersList;
        kafkaConfig.scheme = new SchemeAsMultiScheme(new StringScheme());

        KafkaSpout spout = new KafkaSpout(kafkaConfig);

        TopologyBuilder builder = new TopologyBuilder();
        builder.setSpout("spout", spout, 1);
        builder.setBolt("bolt", new Bolt(), 1).shuffleGrouping("spout");

        Config config = new Config();

        LocalCluster cluster = new LocalCluster();
        cluster.submitTopology("test", config, builder.createTopology());

完整的使用例子，见github源码 https://github.com/tonylee0329/storm-example/blob/master/src/main/java/org/tony/storm_kafka/common/
参考： https://github.com/apache/storm/blob/v0.9.3/external/storm-kafka/README.md

本文为原创，转载请标明出处！From Tony_老七