Spark Streaming程序優雅關閉

流式任務需要 7*24 小時執行，但是有時涉及到升級代碼需要主動停止程序，但是分佈式程序，沒辦法做到一個個進程去殺死，所有配置優雅的關閉就顯得至關重要了。使用外部文件系統來控制內部程序關閉。

其實就是單獨起一個線程專門去專門查找程序是否停止的標誌

import java.net.URI
import org.apache.hadoop.conf.Configuration
import org.apache.hadoop.fs.{FileSystem, Path}
import org.apache.spark.streaming.{StreamingContext, StreamingContextState}
class MonitorStop(ssc: StreamingContext) extends Runnable {
 override def run(): Unit = {
 val fs: FileSystem = FileSystem.get(new URI("hdfs://linux1:9000"), new 
Configuration(), "atguigu")
 while (true) {
 try
 Thread.sleep(5000)
 catch {
 case e: InterruptedException =>
 e.printStackTrace()
 }
 val state: StreamingContextState = ssc.getState
 val bool: Boolean = fs.exists(new Path("hdfs://linux1:9000/stopSpark"))
 if (bool) {
 if (state == StreamingContextState.ACTIVE) {
 ssc.stop(stopSparkContext = true, stopGracefully = true)
 System.exit(0)
 }
 }
 }
 }
}

import org.apache.spark.SparkConf
import org.apache.spark.streaming.dstream.{DStream, ReceiverInputDStream}
import org.apache.spark.streaming.{Seconds, StreamingContext}
object SparkTest {
 def createSSC(): _root_.org.apache.spark.streaming.StreamingContext = {
 val update: (Seq[Int], Option[Int]) => Some[Int] = (values: Seq[Int], status: 
Option[Int]) => {
 //當前批次內容的計算
 val sum: Int = values.sum
 //取出狀態信息中上一次狀態
  val lastStatu: Int = status.getOrElse(0)
 Some(sum + lastStatu)
 }
 val sparkConf: SparkConf = new 
SparkConf().setMaster("local[4]").setAppName("SparkTest")
 //設置優雅的關閉
 sparkConf.set("spark.streaming.stopGracefullyOnShutdown", "true")
 val ssc = new StreamingContext(sparkConf, Seconds(5))
 ssc.checkpoint("./ck")
 val line: ReceiverInputDStream[String] = ssc.socketTextStream("linux1", 9999)
 val word: DStream[String] = line.flatMap(_.split(" "))
 val wordAndOne: DStream[(String, Int)] = word.map((_, 1))
 val wordAndCount: DStream[(String, Int)] = wordAndOne.updateStateByKey(update)
 wordAndCount.print()
 ssc
 }
 def main(args: Array[String]): Unit = {
 val ssc: StreamingContext = StreamingContext.getActiveOrCreate("./ck", () => 
createSSC())
 new Thread(new MonitorStop(ssc)).start()
 ssc.start()
 ssc.awaitTermination()
 }
}