我有一个关于 alpakka_kafka+alpakka_s3 整合。阿尔帕卡s3 multipartUpload 当我使用alpakka-kafka源代码时似乎不会上传文件。

kafkaSource ~> kafkaSubscriber.serializer.deserializeFlow ~> bcast.in
    bcast.out(0) ~> kafkaMsgToByteStringFlow ~> s3Sink
    bcast.out(1) ~> kafkaMsgToOffsetFlow ~> commitFlow ~> Sink.ignore

不过，我一加上 .take(100) Kafka资源之后。一切正常。

kafkaSource.take(100) ~> kafkaSubscriber.serializer.deserializeFlow ~>     bcast.in
    bcast.out(0) ~> kafkaMsgToByteStringFlow ~> s3Sink
    bcast.out(1) ~> kafkaMsgToOffsetFlow ~> commitFlow ~> Sink.ignore

任何帮助都将不胜感激。提前谢谢！
以下是完整的代码片段：

// Source
val kafkaSource: Source[(CommittableOffset, Array[Byte]), Consumer.Control] = {
    Consumer
      .committableSource(consumerSettings, Subscriptions.topics(prefixedTopics))
      .map(committableMessage => (committableMessage.committableOffset, committableMessage.record.value))
      .watchTermination() { (mat, f: Future[Done]) =>
        f.foreach { _ =>
          log.debug("consumer source shutdown, consumerId={}, group={}, topics={}", consumerId, group,     prefixedTopics.mkString(", "))
        }
        mat
      }
  }
// Flow
val commitFlow: Flow[CommittableOffset, Done, NotUsed] = {
    Flow[CommittableOffset]
      .groupedWithin(batchingSize, batchingInterval)
      .map(group => group.foldLeft(CommittableOffsetBatch.empty) { (batch, elem) => batch.updated(elem) })
      .mapAsync(parallelism = 3) { msg =>
        log.debug("committing offset, msg={}", msg)
        msg.commitScaladsl().map { result =>
          log.debug("committed offset, msg={}", msg)
          result
        }
      }
  }
private val kafkaMsgToByteStringFlow = Flow[KafkaMessage[Any]].map(x => ByteString(x.msg + "\n"))
private val kafkaMsgToOffsetFlow = {
    implicit val askTimeout: Timeout = Timeout(5.seconds)
    Flow[KafkaMessage[Any]].mapAsync(parallelism = 5) { elem =>
      Future(elem.offset)
    }
  }
// Sink
val s3Sink = {
      val BUCKET = "test-data"
      s3Client.multipartUpload(BUCKET, s"tmp/data.txt")
// Doesnt' work..... ( no files are showing up on the S3)
kafkaSource ~> kafkaSubscriber.serializer.deserializeFlow ~> bcast.in
        bcast.out(0) ~> kafkaMsgToByteStringFlow ~> s3Sink
        bcast.out(1) ~> kafkaMsgToOffsetFlow ~> commitFlow ~> Sink.ignore
// This one works...
kafkaSource.take(100) ~> kafkaSubscriber.serializer.deserializeFlow ~> bcast.in
        bcast.out(0) ~> kafkaMsgToByteStringFlow ~> s3Sink
        bcast.out(1) ~> kafkaMsgToOffsetFlow ~> commitFlow ~> Sink.ignore