Akka/Scala example source code file (SnapshotFailureRobustnessSpec.scala)

This example Akka source code file (SnapshotFailureRobustnessSpec.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

actorref, akka, concurrent, error, failinglocalsnapshotstore, localsnapshotstore, namedprocessor, persistence, persistent, snapshotfailurerobustnessspec, snapshotmetadata, snapshotoffer, string, test, testing, time

The SnapshotFailureRobustnessSpec.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */

package akka.persistence

import akka.actor.{ Props, ActorRef }
import akka.testkit.{ TestEvent, EventFilter, ImplicitSender, AkkaSpec }
import scala.concurrent.duration._
import akka.persistence.snapshot.local.LocalSnapshotStore
import akka.persistence.serialization.Snapshot
import akka.event.Logging

import scala.language.postfixOps

object SnapshotFailureRobustnessSpec {

  class SaveSnapshotTestProcessor(name: String, probe: ActorRef) extends NamedProcessor(name) {
    def receive = {
      case Persistent(payload, snr) ⇒ saveSnapshot(payload)
      case SaveSnapshotSuccess(md)  ⇒ probe ! md.sequenceNr
      case SnapshotOffer(md, s)     ⇒ probe ! ((md, s))
      case other                    ⇒ probe ! other
    }
  }

  class LoadSnapshotTestProcessor(name: String, probe: ActorRef) extends NamedProcessor(name) {
    def receive = {
      case Persistent(payload, snr) ⇒ probe ! s"${payload}-${snr}"
      case SnapshotOffer(md, s)     ⇒ probe ! ((md, s))
      case other                    ⇒ probe ! other
    }
    override def preStart() = ()
  }

  class FailingLocalSnapshotStore extends LocalSnapshotStore {
    override def save(metadata: SnapshotMetadata, snapshot: Any): Unit = {
      if (metadata.sequenceNr == 2) {
        val bytes = "b0rk".getBytes("UTF-8")
        withOutputStream(metadata)(_.write(bytes))
      } else super.save(metadata, snapshot)
    }
  }
}

class SnapshotFailureRobustnessSpec extends AkkaSpec(PersistenceSpec.config("leveldb", "SnapshotFailureRobustnessSpec", serialization = "off", extraConfig = Some(
  """
    |akka.persistence.snapshot-store.local.class = "akka.persistence.SnapshotFailureRobustnessSpec$FailingLocalSnapshotStore"
  """.stripMargin))) with PersistenceSpec with ImplicitSender {

  import SnapshotFailureRobustnessSpec._

  "A processor with a failing snapshot" must {
    "recover state starting from the most recent complete snapshot" in {
      val sProcessor = system.actorOf(Props(classOf[SaveSnapshotTestProcessor], name, testActor))
      val persistenceId = name

      expectMsg(RecoveryCompleted)
      sProcessor ! Persistent("blahonga")
      expectMsg(1)
      sProcessor ! Persistent("kablama")
      expectMsg(2)
      system.eventStream.publish(TestEvent.Mute(
        EventFilter.error(start = "Error loading snapshot [")))
      system.eventStream.subscribe(testActor, classOf[Logging.Error])
      try {
        val lProcessor = system.actorOf(Props(classOf[LoadSnapshotTestProcessor], name, testActor))
        lProcessor ! Recover()
        expectMsgPF() {
          case (SnapshotMetadata(`persistenceId`, 1, timestamp), state) ⇒
            state should be("blahonga")
            timestamp should be > (0L)
        }
        expectMsg("kablama-2")
        expectMsg(RecoveryCompleted)
        expectNoMsg(1 second)
      } finally {
        system.eventStream.unsubscribe(testActor, classOf[Logging.Error])
        system.eventStream.publish(TestEvent.UnMute(
          EventFilter.error(start = "Error loading snapshot [")))
      }
    }
  }
}