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

This example Akka source code file (Snapshotter.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

actor, akka, any, deletesnapshot, deletesnapshots, loadsnapshot, long, persistence, savesnapshot, snapshotselectioncriteria, string, unit

The Snapshotter.scala Akka example source code

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

package akka.persistence

import akka.actor._
import akka.persistence.SnapshotProtocol._

/**
 * Snapshot API on top of the internal snapshot protocol.
 */
trait Snapshotter extends Actor {
  private lazy val snapshotStore = Persistence(context.system).snapshotStoreFor(snapshotterId)

  /**
   * Snapshotter id.
   */
  def snapshotterId: String

  /**
   * Sequence number to use when taking a snapshot.
   */
  def snapshotSequenceNr: Long

  def loadSnapshot(persistenceId: String, criteria: SnapshotSelectionCriteria, toSequenceNr: Long) =
    snapshotStore ! LoadSnapshot(persistenceId, criteria, toSequenceNr)

  /**
   * Saves a `snapshot` of this snapshotter's state. If saving succeeds, this snapshotter will receive a
   * [[SaveSnapshotSuccess]] message, otherwise a [[SaveSnapshotFailure]] message.
   */
  def saveSnapshot(snapshot: Any): Unit = {
    snapshotStore ! SaveSnapshot(SnapshotMetadata(snapshotterId, snapshotSequenceNr), snapshot)
  }

  /**
   * Deletes a snapshot identified by `sequenceNr` and `timestamp`.
   */
  def deleteSnapshot(sequenceNr: Long, timestamp: Long): Unit = {
    snapshotStore ! DeleteSnapshot(SnapshotMetadata(snapshotterId, sequenceNr, timestamp))
  }

  /**
   * Deletes all snapshots matching `criteria`.
   */
  def deleteSnapshots(criteria: SnapshotSelectionCriteria): Unit = {
    snapshotStore ! DeleteSnapshots(snapshotterId, criteria)
  }

}