Working on kafka.

project/SparkBuild.scala

@@ -156,7 +156,9 @@ object SparkBuild extends Build {
   def bagelSettings = sharedSettings ++ Seq(name := "spark-bagel")
 
   def streamingSettings = sharedSettings ++ Seq(
-    name := "spark-streaming"
+    name := "spark-streaming",
+    libraryDependencies ++= Seq(
+      "kafka" % "core-kafka_2.9.1" % "0.7.2")
   ) ++ assemblySettings ++ extraAssemblySettings
 
   def extraAssemblySettings() = Seq(test in assembly := {}) ++ Seq(

streaming/src/main/scala/spark/streaming/StreamingContext.scala

@@ -86,6 +86,17 @@ class StreamingContext (
 
   private[streaming] def getNewNetworkStreamId() = nextNetworkInputStreamId.getAndIncrement()
 
+  def kafkaStream[T: ClassManifest](
+      hostname: String,
+      port: Int,
+      groupId: String,
+      storageLevel: StorageLevel = StorageLevel.MEMORY_ONLY_SER_2
+    ): DStream[T] = {
+    val inputStream = new KafkaInputDStream[T](this, hostname, port, groupId, storageLevel)
+    graph.addInputStream(inputStream)
+    inputStream
+  }
+
   def networkTextStream(
       hostname: String,
       port: Int,

streaming/src/main/scala/spark/streaming/examples/KafkaWordCount.scala

@@ -0,0 +1,27 @@
+package spark.streaming.examples
+
+import spark.streaming.{Seconds, StreamingContext, KafkaInputDStream}
+import spark.streaming.StreamingContext._
+import spark.storage.StorageLevel
+
+object KafkaWordCount {
+  def main(args: Array[String]) {
+    if (args.length < 2) {
+      System.err.println("Usage: WordCountNetwork <master> <hostname> <port>")
+      System.exit(1)
+    }
+
+    // Create the context and set the batch size
+    val ssc = new StreamingContext(args(0), "WordCountNetwork")
+    ssc.setBatchDuration(Seconds(2))
+
+    // Create a NetworkInputDStream on target ip:port and count the
+    // words in input stream of \n delimited test (eg. generated by 'nc') 
+    val lines = ssc.kafkaStream[String](args(1), args(2).toInt, "test_group")
+    val words = lines.flatMap(_.split(" "))
+    val wordCounts = words.map(x => (x, 1)).reduceByKey(_ + _)
+    wordCounts.print()
+    ssc.start()
+
+  }
+}

streaming/src/main/scala/spark/streaming/input/KafkaInputDStream.scala

@@ -0,0 +1,121 @@
+package spark.streaming
+
+import java.nio.ByteBuffer
+import java.util.Properties
+import java.util.concurrent.{ArrayBlockingQueue, Executors}
+import kafka.api.{FetchRequest}
+import kafka.consumer.{Consumer, ConsumerConfig, KafkaStream}
+import kafka.javaapi.consumer.SimpleConsumer
+import kafka.javaapi.message.ByteBufferMessageSet
+import kafka.message.{Message, MessageSet, MessageAndMetadata}
+import kafka.utils.Utils
+import scala.collection.JavaConversions._
+import spark._
+import spark.RDD
+import spark.storage.StorageLevel
+
+
+/**
+ * An input stream that pulls messages form a Kafka Broker.
+ */
+class KafkaInputDStream[T: ClassManifest](
+    @transient ssc_ : StreamingContext,
+    host: String,
+    port: Int,
+    groupId: String,
+    storageLevel: StorageLevel,
+    timeout: Int = 10000,
+    bufferSize: Int = 1024000
+  ) extends NetworkInputDStream[T](ssc_ ) with Logging {
+
+  def createReceiver(): NetworkReceiver[T] = {
+    new KafkaReceiver(id, host, port, storageLevel, groupId, timeout).asInstanceOf[NetworkReceiver[T]]
+  }
+}
+
+class KafkaReceiver(streamId: Int, host: String, port: Int, storageLevel: StorageLevel, groupId: String, timeout: Int)
+  extends NetworkReceiver[Any](streamId) {
+
+  //var executorPool : = null
+  var blockPushingThread : Thread = null
+
+  def onStop() {
+    blockPushingThread.interrupt()
+  }
+
+  def onStart() {
+
+    val executorPool = Executors.newFixedThreadPool(2)
+
+    logInfo("Starting Kafka Consumer with groupId " + groupId)
+
+    val zooKeeperEndPoint = host + ":" + port
+    logInfo("Connecting to " + zooKeeperEndPoint)
+
+    // Specify some consumer properties
+    val props = new Properties()
+    props.put("zk.connect", zooKeeperEndPoint)
+    props.put("zk.connectiontimeout.ms", timeout.toString)
+    props.put("groupid", groupId)
+
+    // Create the connection to the cluster
+    val consumerConfig = new ConsumerConfig(props)
+    val consumerConnector = Consumer.create(consumerConfig)
+    logInfo("Connected to " + zooKeeperEndPoint)
+    logInfo("")
+    logInfo("")
+
+    // Specify which topics we are listening to
+    val topicCountMap = Map("test" -> 2)
+    val topicMessageStreams = consumerConnector.createMessageStreams(topicCountMap)
+    val streams = topicMessageStreams.get("test")
+    
+    // Queue that holds the blocks
+    val queue = new ArrayBlockingQueue[ByteBuffer](2)
+
+    streams.getOrElse(Nil).foreach { stream =>
+      executorPool.submit(new MessageHandler(stream, queue))
+    }
+
+    blockPushingThread = new DaemonThread {
+      override def run() {
+        logInfo("Starting BlockPushingThread.")
+        var nextBlockNumber = 0
+        while (true) {
+          val buffer = queue.take()
+          val blockId = "input-" + streamId + "-" + nextBlockNumber
+          nextBlockNumber += 1
+          pushBlock(blockId, buffer, storageLevel)
+        }
+      }
+    }
+    blockPushingThread.start()
+
+    // while (true) {
+    //   // Create a fetch request for topic “test”, partition 0, current offset, and fetch size of 1MB
+    //   val fetchRequest = new FetchRequest("test", 0, offset, 1000000)
+
+    //   // get the message set from the consumer and print them out
+    //   val messages = consumer.fetch(fetchRequest)
+    //   for(msg <- messages.iterator) {
+    //     logInfo("consumed: " + Utils.toString(msg.message.payload, "UTF-8"))
+    //     // advance the offset after consuming each message
+    //     offset = msg.offset
+    //     queue.put(msg.message.payload)
+    //   }
+    // }
+  }
+
+  class MessageHandler(stream: KafkaStream[Message], queue: ArrayBlockingQueue[ByteBuffer]) extends Runnable {
+    def run() {
+      logInfo("Starting MessageHandler.")
+      while(true) {
+        stream.foreach { msgAndMetadata => 
+          logInfo("Consumed: " + Utils.toString(msgAndMetadata.message.payload, "UTF-8"))
+          queue.put(msgAndMetadata.message.payload)
+        }
+      }      
+    }
+  }
+
+}