SparkStreaming+Zookeeper+Kafka入门程序

准备工作：

• 安装 spark
• 安装 zookeeper
• 安装 kafka

开始工作

1. 启动zookeeper

打开终端，切换到 zookeeper HOME 目录， 进入conf文件夹，拷贝一份 zoo_sample.cfg 副本并重命名为 zoo.cfg
切换到上级的bin目录中，执行 ./zkServer.sh start 启动zookeeper，会有日志打印

Starting zookeeper ... STARTED

然后用 ./zkServer.sh status 查看状态，如果有下列信息输出，则说明启动成功

Mode: standalone

如果要停止zookeeper，则运行 ./zkServer stop 即可

2. 启动kafka

打开终端，切换到 kafka HOME 目录,运行 bin/kafka-server-start.sh config/server.properties 会有以下类似日志输出

[2014-11-12 17:38:13,395] INFO [ReplicaFetcherManager on broker 0] Removed fetcher for partitions [test,0] (kafka.server.ReplicaFetcherManager)
[2014-11-12 17:38:13,420] INFO [ReplicaFetcherManager on broker 0] Removed fetcher for partitions [test,0] (kafka.server.ReplicaFetcherManager)

3. 启动kafka生产者

重新打开一个终端，暂叫做 生产者终端，方便后面引用说明。切换到 kafka HOME 目录,运行 bin/kafka-console-producer.sh --broker-list localhost:9092 --topic test 创建一个叫 test 的主题。

4. 编写scala应用程序

    package test
    import java.util.Properties
    import kafka.producer._
    import org.apache.spark.streaming._
    import org.apache.spark.streaming.StreamingContext._
    import org.apache.spark.streaming.kafka._
    import org.apache.spark.SparkConf


    object KafkaWordCount {
      def main(args: Array[String]) {
    //    if (args.length < 4) {
    //      System.err.println("Usage: KafkaWordCount        ")
    //      System.exit(1)
     //    }

    //    StreamingExamples.setStreamingLogLevels()

    //val Array(zkQuorum, group, topics, numThreads) = args
    val zkQuorum = "localhost:2181"
    val group = "1"
    val topics = "test"
    val numThreads = 2
    
    val sparkConf = new SparkConf().setAppName("KafkaWordCount").setMaster("local[2]")
    val ssc =  new StreamingContext(sparkConf, Seconds(2))
    ssc.checkpoint("checkpoint")

    val topicpMap = topics.split(",").map((_,numThreads)).toMap
    val lines = KafkaUtils.createStream(ssc, zkQuorum, group, topicpMap).map(_._2)
    val words = lines.flatMap(_.split(" "))
    
    val pairs = words.map(word => (word, 1))
    
    val wordCounts = pairs.reduceByKey(_ + _)
    
    //val wordCounts = words.map(x => (x, 1L))
    //  .reduceByKeyAndWindow(_ + _, _ - _, Minutes(10), Seconds(2), 2)
    wordCounts.print()

    ssc.start()
    ssc.awaitTermination()
  }
}

build.sbt 文件中添加依赖

libraryDependencies += "org.apache.spark" % "spark-streaming_2.10" % "1.1.0"

libraryDependencies += "org.apache.spark" % "spark-streaming-kafka_2.10" % "1.1.0"

启动scala程序，然后在 上面第2步的 生产者终端中输入一些字符串，如 sdfsadf a aa a a a a a a a a ，在ide的控制台上可以看到有信息输出

4/11/12 16:38:22 INFO scheduler.DAGScheduler: Stage 195 (take at DStream.scala:608) finished in 0.004 s
-------------------------------------------
Time: 1415781502000 ms
-------------------------------------------
(aa,1)
(a,9)
(sdfsadf,1)

说明程序成功运行。