Spark Streaming程序优雅关闭

流式任务需要 7*24 小时执行，但是有时涉及到升级代码需要主动停止程序，但是分布式程序，没办法做到一个个进程去杀死，所有配置优雅的关闭就显得至关重要了。使用外部文件系统来控制内部程序关闭。

其实就是单独起一个线程专门去专门查找程序是否停止的标志

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]) => {
 //当前批次内容的计算
 val sum: Int = values.sum
 //取出状态信息中上一次状态
  val lastStatu: Int = status.getOrElse(0)
 Some(sum + lastStatu)
 }
 val sparkConf: SparkConf = new 
SparkConf().setMaster("local[4]").setAppName("SparkTest")
 //设置优雅的关闭
 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()
 }
}