概述

StreamingListener 是针对spark streaming的各个阶段的事件监听机制。

StreamingListener接口

//需要监听spark streaming中各个阶段的事件只需实现这个特质中对应的事件函数即可
//本身既有注释说明
trait StreamingListener {
  /** Called when the streaming has been started */
  /** streaming 启动的事件 */
  def onStreamingStarted(streamingStarted: StreamingListenerStreamingStarted) { }
  /** Called when a receiver has been started */
  /** 接收启动事件 */
  def onReceiverStarted(receiverStarted: StreamingListenerReceiverStarted) { }
  /** Called when a receiver has reported an error */
  def onReceiverError(receiverError: StreamingListenerReceiverError) { }
  /** Called when a receiver has been stopped */
  def onReceiverStopped(receiverStopped: StreamingListenerReceiverStopped) { }
  /** Called when a batch of jobs has been submitted for processing. */
  /** 每个批次提交的事件 */
  def onBatchSubmitted(batchSubmitted: StreamingListenerBatchSubmitted) { }
  /** Called when processing of a batch of jobs has started.  */
  /** 每个批次启动的事件 */
  def onBatchStarted(batchStarted: StreamingListenerBatchStarted) { }
  /** Called when processing of a batch of jobs has completed. */
  /** 每个批次完成的事件  */
  def onBatchCompleted(batchCompleted: StreamingListenerBatchCompleted) { }
  /** Called when processing of a job of a batch has started. */
  def onOutputOperationStarted(
      outputOperationStarted: StreamingListenerOutputOperationStarted) { }
  /** Called when processing of a job of a batch has completed. */
  def onOutputOperationCompleted(
      outputOperationCompleted: StreamingListenerOutputOperationCompleted) { }
}

自定义StreamingListener

功能：监控批次处理时间，若超过阈值则告警，每次告警间隔2分钟

class SparkStreamingDelayListener(private val appName:String, private val duration: Int,private val times: Int) extends StreamingListener{
  private val logger = LoggerFactory.getLogger("SparkStreamingDelayListener")
//每个批次完成时执行
  override def onBatchCompleted(batchCompleted: StreamingListenerBatchCompleted): Unit = {
    val batchInfo = batchCompleted.batchInfo
    val processingStartTime = batchCompleted.batchInfo.processingStartTime
    val numRecords = batchCompleted.batchInfo.numRecords
    val processingEndTime = batchInfo.processingEndTime
    val processingDelay = batchInfo.processingDelay
    val totalDelay = batchInfo.totalDelay
    //将每次告警时间写入redis,用以判断告警间隔大于2分钟
    val jedis = RedisClusterClient.getJedisClusterClient()
    val current_time = (System.currentTimeMillis / 1000).toInt
    val redis_time = jedis.get(appName)
    var flag = false
    if(redis_time==null || current_time-redis_time.toInt>120){
      jedis.set(appName,current_time.toString)
      flag = true
    }
    
    //若批次处理延迟大于批次时长指定倍数，并且告警间隔大约2分钟，则告警
    if(totalDelay.get >= times * duration * 1000 && flag){
      val monitorContent = appName+": numRecords ->"+numRecords+",processingDelay ->"+processingDelay.get/1000+" s,totalDelay -> "+totalDelay.get/1000+"s"
      println(monitorContent)
      val msg = "Streaming_"+appName+"_DelayTime:"+totalDelay.get/1000+"S"
      val getURL = "http://node1:8002/message/weixin?msg="+msg
      HttpClient.doGet(getURL)
    }
  }
}

应用

//streamingListener不需要在配置中设置，可以直接添加到streamingContext中
object My{
    def main(args : Array[String]) : Unit = {
        val sparkConf = new SparkConf()
        val ssc = new StreamingContext(sparkConf,Seconds(20))
        ssc.addStreamingListener(new SparkStreamingDelayListener("Userid2Redis", duration,times))
        ....
    }
}

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