Akka Streams Resuming Materializer does not log exceptions

[dol...@thoughtworks.com]

Hello all,

When I provide a resuming materializer to the stream, the exceptions that occurred in the stream do not get logged. Is there any way to log these exceptions ?

import akka.actor.ActorSystem
import akka.stream.scaladsl.Source
import akka.stream.{ActorMaterializer, ActorMaterializerSettings, Materializer, Supervision}

import scala.concurrent.duration.DurationInt

object Demo extends App {

  private implicit val actorSystem: ActorSystem = ActorSystem()

  lazy val settings: ActorMaterializerSettings =
    ActorMaterializerSettings(actorSystem).withSupervisionStrategy(Supervision.getResumingDecider)

  implicit lazy val resumingMat: Materializer = ActorMaterializer(settings)

  var counter = 0
  def eventGenerator(): Int = {
    counter += 1
    if (counter > 5) throw new RuntimeException("Could not create an event")
    else 1
  }

  Source.tick(0.millis, 10.millis, ()).map(_ ⇒ eventGenerator()).runForeach(println)
}

[Konrad “ktoso” Malawski]

Use the .log() operator.

Same as exceptions thrown in a Future do not automatically get logged.

There has been discussion about enabling this always, however you’d then be swamped with errors which are recovered and actually “fine and nothing to worry about”.

If you want logging, put a log() there.

PS: New discussion forum: https://discuss.akka.io/ replacing akka-user google-group soon. :-)

-- 

Cheers,

Konrad 'ktoso' Malawski

Akka @ Lightbend

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[dol...@thoughtworks.com]

Hi Konrad,

Thanks for your response. I have started a thread in discuss.lightbend as suggested by you. I've posted a follow-up question on that. Looking forward for your reply.

Thanks,

Dolly