java Flink CEP不在事件时间工作，但在处理时间工作

Question

当我使用Flink CEP代码处理时间（默认配置）时，我能够获得所需的模式匹配，但在配置env to Event time时，我无法获得任何模式匹配

 def main(args: Array[String]): Unit = {
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime)
    env.enableCheckpointing(3000) // checkpoint every 3000 msec
     val lines = env.addSource(consumerKafkaSource.consume("bank_transaction_2", "192.168.2.201:9092", "192.168.2.201:2181", "http://192.168.2.201:8081"))

  val eventdate = ExtractAndAssignEventTime.assign(lines, "unix", "datetime", 3) //Extracting date time here

    val event = eventdate.keyBy(v => v.get("customer_id").toString.toInt)
   val pattern1 = Pattern.begin[GenericRecord]("start").where(v=>v.get("state").toString=="FAILED").next("d").where(v=>v.get("state").toString=="FAILED")
      val patternStream = CEP.pattern(event, pattern1)
    val warnID = patternStream.sideOutputLateData(latedata).select(value =>  {
      val v = value.mapValues(c => c.toList.toString)
      Json(DefaultFormats).write(v).replace("\\\"", "\"")
        //.replace("List(","{").replace(")","}")
    })
    val latedatastream = warnID.getSideOutput(latedata)
    latedatastream.print("late_data")


    warnID.print("warning")
    event.print("event")

时间戳提取代码

object ExtractAndAssignEventTime {
  def assign(stream:DataStream[GenericRecord],timeFormat:String,timeColumn:String,OutofOrderTime:Int ):DataStream[GenericRecord] ={
    if(!(timeFormat.equalsIgnoreCase("Unix"))){
      val EventTimeStream=stream.assignTimestampsAndWatermarks(new BoundedOutOfOrdernessTimestampExtractor[GenericRecord](Time.seconds(3)) {
        override def extractTimestamp(t: GenericRecord): Long = {
          new java.text.SimpleDateFormat(timeFormat).parse(t.get(timeColumn).toString).getTime
        }
      })
      EventTimeStream
    }
    else{
      val EventTimeStream=stream.assignTimestampsAndWatermarks(new BoundedOutOfOrdernessTimestampExtractor[GenericRecord](Time.seconds(OutofOrderTime)) {
        override def extractTimestamp(t: GenericRecord): Long = {
          (t.get(timeColumn).toString.toLong)
        }
      })
      EventTimeStream
    }
  }

请帮我解决这个问题。提前谢谢

Answer 1

因为您使用的是AssingerWithPeriodicWatermark，所以还需要设置setAutowatermarkInterval，以便Flink使用这个间隔来生成水印

您可以通过调用env.getConfig.setAutoWatermarkInterval([interval])来实现这一点

对于事件时间，CEP基于水印，因此如果不生成水印，则基本上不会有输出

Answer 2

我也有同样的问题，我刚刚“解决”了它，但答案没有多大意义（至少对我来说），你会看到的

说明：

在我最初的代码中，我有：

var env = StreamExecutionEnvironment.getExecutionEnvironment
env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime)
env.setParallelism(1)
env.getConfig.setAutoWatermarkInterval(1)

...

var stream : DataStream[String] = env.readTextFile("/home/luca/Desktop/input")
    
    
var tupleStream = stream.map(new S2TMapFunction())
tupleStream.assignTimestampsAndWatermarks(new PlacasPunctualTimestampAssigner())

val pattern = Pattern.begin[(String,Double,Double,String,Int,Int)]("follow").where(new SameRegionFunction())

val patternStream = CEP.pattern(newTupleStream,pattern)

val result = patternStream.process(new MyPatternProcessFunction())

根据我的日志记录，我看到SameRegionFunction和MyPatternProcessFunction都没有被执行，至少可以说这是非常出乎意料的

答复:

由于我一无所知，我决定测试让我的流再经过一个转换函数，只是为了检查我的事件是否真的被插入流中。因此，我将tupleStream提交给一个映射操作，生成newTupleStream，如下所示：

var env = StreamExecutionEnvironment.getExecutionEnvironment
env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime)
env.setParallelism(1)
env.getConfig.setAutoWatermarkInterval(1)

...

var stream : DataStream[String] = env.readTextFile("/home/luca/Desktop/input")


/* I created 'DoNothingMapFunction', where the output event = input event*/
var tupleStream = stream.map(new S2TMapFunction())
var newTupleStream = tupleStream.assignTimestampsAndWatermarks(new PlacasPunctualTimestampAssigner()).map(new DoNothingMapFunction())


val pattern = Pattern.begin[(String,Double,Double,String,Int,Int)]("follow").where(new SameRegionFunction())

val patternStream = CEP.pattern(newTupleStream,pattern)

val result = patternStream.process(new MyPatternProcessFunction())

然后SameRegionFunction和MyPatternProcessFunction决定运行

Obs:

我换了一行：

var newTupleStream = tupleStream.assignTimestampsAndWatermarks(new PlacasPunctualTimestampAssigner()).map(new DoNothingMapFunction())

为此：

var newTupleStream = tupleStream.assignTimestampsAndWatermarks(new PlacasPunctualTimestampAssigner())

它也起了作用。显然，仅仅是另一个间接层次就足以让它发挥作用，尽管我不清楚它为什么会发生