examples/streaming/state/src/main/scala/org/apache/gearpump/streaming/examples/state/WindowAverageApp.scala

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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package org.apache.gearpump.streaming.examples.state

import akka.actor.ActorSystem
import org.apache.hadoop.conf.Configuration

import org.apache.gearpump.cluster.UserConfig
import org.apache.gearpump.cluster.client.ClientContext
import org.apache.gearpump.cluster.main.{ArgumentsParser, CLIOption, ParseResult}
import org.apache.gearpump.partitioner.HashPartitioner
import org.apache.gearpump.streaming.examples.state.processor.{NumberGeneratorProcessor, WindowAverageProcessor}
import org.apache.gearpump.streaming.hadoop.HadoopCheckpointStoreFactory
import org.apache.gearpump.streaming.state.impl.{PersistentStateConfig, WindowConfig}
import org.apache.gearpump.streaming.{Processor, StreamApplication}
import org.apache.gearpump.util.Graph.Node
import org.apache.gearpump.util.{AkkaApp, Graph}

/** Does exactly-once sliding window based average aggregation */
object WindowAverageApp extends AkkaApp with ArgumentsParser {

  override val options: Array[(String, CLIOption[Any])] = Array(
    "gen" -> CLIOption("<how many gen tasks>", required = false, defaultValue = Some(1)),
    "window" -> CLIOption("<how mange window tasks", required = false, defaultValue = Some(1)),
    "window_size" -> CLIOption("<window size in milliseconds>", required = false,
      defaultValue = Some(5000)),
    "window_step" -> CLIOption("<window step in milliseconds>", required = false,
      defaultValue = Some(5000))
  )

  def application(config: ParseResult)(implicit system: ActorSystem): StreamApplication = {
    val windowSize = config.getInt("window_size")
    val windowStep = config.getInt("window_step")
    val checkpointStoreFactory = new HadoopCheckpointStoreFactory("MessageCount", new Configuration)
    val taskConfig = UserConfig.empty.
      withBoolean(PersistentStateConfig.STATE_CHECKPOINT_ENABLE, true)
      .withLong(PersistentStateConfig.STATE_CHECKPOINT_INTERVAL_MS, 1000L)
      .withValue(PersistentStateConfig.STATE_CHECKPOINT_STORE_FACTORY, checkpointStoreFactory)
      .withValue(WindowConfig.NAME, WindowConfig(windowSize, windowStep))
    val gen = Processor[NumberGeneratorProcessor](config.getInt("gen"))
    val count = Processor[WindowAverageProcessor](config.getInt("window"), taskConf = taskConfig)
    val partitioner = new HashPartitioner()
    val app = StreamApplication("WindowAverage", Graph(gen ~ partitioner ~> count),
      UserConfig.empty)
    app
  }

  override def main(akkaConf: Config, args: Array[String]): Unit = {
    val config = parse(args)
    val context = ClientContext(akkaConf)

    implicit val system = context.system
    val appId = context.submit(application(config))
    context.close()
  }
}