/*
 * 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.
 */

// scalastyle:off println
package org.apache.spark.examples.streaming

import org.apache.spark.SparkConf
import org.apache.spark.storage.StorageLevel
import org.apache.spark.streaming._
import org.apache.spark.streaming.flume._
import org.apache.spark.util.IntParam

/**
 *  Produces a count of events received from Flume.
 *
 *  This should be used in conjunction with an AvroSink in Flume. It will start
 *  an Avro server on at the request host:port address and listen for requests.
 *  Your Flume AvroSink should be pointed to this address.
 *
 *  Usage: FlumeEventCount <host> <port>
 *    <host> is the host the Flume receiver will be started on - a receiver
 *           creates a server and listens for flume events.
 *    <port> is the port the Flume receiver will listen on.
 *
 *  To run this example:
 *    `$ bin/run-example org.apache.spark.examples.streaming.FlumeEventCount <host> <port> `
 */
object FlumeEventCount {
  def main(args: Array[String]) {
    if (args.length < 2) {
      System.err.println(
        "Usage: FlumeEventCount <host> <port>")
      System.exit(1)
    }

    StreamingExamples.setStreamingLogLevels()

    val Array(host, IntParam(port)) = args

    val batchInterval = Milliseconds(2000)

    // Create the context and set the batch size
    val sparkConf = new SparkConf().setAppName("FlumeEventCount")
    val ssc = new StreamingContext(sparkConf, batchInterval)

    // Create a flume stream
    val stream = FlumeUtils.createStream(ssc, host, port, StorageLevel.MEMORY_ONLY_SER_2)

    // Print out the count of events received from this server in each batch
    stream.count().map(cnt => "Received " + cnt + " flume events." ).print()

    ssc.start()
    ssc.awaitTermination()
  }
}
// scalastyle:on println
