akka.persistence

AtLeastOnceDelivery

trait AtLeastOnceDelivery extends Processor

Mix-in this trait with your PersistentActor to send messages with at-least-once delivery semantics to destinations. It takes care of re-sending messages when they have not been confirmed within a configurable timeout. Use the #deliver method to send a message to a destination. Call the #confirmDelivery method when the destination has replied with a confirmation message.

At-least-once delivery implies that original message send order is not always retained and the destination may receive duplicate messages due to possible resends.

The interval between redelivery attempts can be defined by #redeliverInterval. After a number of delivery attempts a AtLeastOnceDelivery.UnconfirmedWarning message will be sent to self. The re-sending will still continue, but you can choose to call #confirmDelivery to cancel the re-sending.

The AtLeastOnceDelivery trait has a state consisting of unconfirmed messages and a sequence number. It does not store this state itself. You must persist events corresponding to the deliver and confirmDelivery invocations from your PersistentActor so that the state can be restored by calling the same methods during the recovery phase of the PersistentActor. Sometimes these events can be derived from other business level events, and sometimes you must create separate events. During recovery calls to deliver will not send out the message, but it will be sent later if no matching confirmDelivery was performed.

Support for snapshots is provided by #getDeliverySnapshot and #setDeliverySnapshot. The AtLeastOnceDeliverySnapshot contains the full delivery state, including unconfirmed messages. If you need a custom snapshot for other parts of the actor state you must also include the AtLeastOnceDeliverySnapshot. It is serialized using protobuf with the ordinary Akka serialization mechanism. It is easiest to include the bytes of the AtLeastOnceDeliverySnapshot as a blob in your custom snapshot.

Source
AtLeastOnceDelivery.scala
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  1. AtLeastOnceDelivery
  2. Processor
  3. ProcessorImpl
  4. Recovery
  5. StashFactory
  6. Stash
  7. RequiresMessageQueue
  8. UnrestrictedStash
  9. StashSupport
  10. Snapshotter
  11. Actor
  12. AnyRef
  13. Any
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Type Members

  1. type Receive = PartialFunction[Any, Unit]

    Definition Classes
    Actor

Abstract Value Members

  1. abstract def receive: actor.Actor.Receive

    This defines the initial actor behavior, it must return a partial function with the actor logic.

    This defines the initial actor behavior, it must return a partial function with the actor logic.

    Definition Classes
    Actor

Concrete Value Members

  1. final def !=(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  2. final def !=(arg0: Any): Boolean

    Definition Classes
    Any
  3. final def ##(): Int

    Definition Classes
    AnyRef → Any
  4. def +(other: String): String

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to StringAdd performed by method any2stringadd in scala.Predef.
    Definition Classes
    StringAdd
  5. def ->[B](y: B): (AtLeastOnceDelivery, B)

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to ArrowAssoc[AtLeastOnceDelivery] performed by method any2ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  6. final def ==(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  7. final def ==(arg0: Any): Boolean

    Definition Classes
    Any
  8. def aroundPostRestart(reason: Throwable): Unit

    Can be overridden to intercept calls to postRestart.

    Can be overridden to intercept calls to postRestart. Calls postRestart by default.

    Attributes
    protected[akka]
    Definition Classes
    Actor
  9. def aroundPostStop(): Unit

    INTERNAL API

    INTERNAL API

    Attributes
    protected[akka]
    Definition Classes
    AtLeastOnceDelivery → ProcessorImpl → Actor
  10. def aroundPreRestart(reason: Throwable, message: Option[Any]): Unit

    INTERNAL API

    INTERNAL API

    Attributes
    protected[akka]
    Definition Classes
    AtLeastOnceDelivery → ProcessorImpl → Actor
  11. def aroundPreStart(): Unit

    INTERNAL API.

    INTERNAL API.

    Attributes
    protected[akka]
    Definition Classes
    ProcessorImpl → Actor
  12. def aroundReceive(receive: Receive, message: Any): Unit

    INTERNAL API

    INTERNAL API

    receive

    current behavior.

    Attributes
    protected[akka]
    Definition Classes
    AtLeastOnceDeliveryRecoveryActor
  13. final def asInstanceOf[T0]: T0

    Definition Classes
    Any
  14. def clone(): AnyRef

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  15. def confirmDelivery(deliveryId: Long): Boolean

    Call this method when a message has been confirmed by the destination, or to abort re-sending.

    Call this method when a message has been confirmed by the destination, or to abort re-sending.

    returns

    true the first time the deliveryId is confirmed, i.e. false for duplicate confirm

    See also

    #deliver

  16. implicit val context: ActorContext

    Stores the context for this actor, including self, and sender.

    Stores the context for this actor, including self, and sender. It is implicit to support operations such as forward.

    WARNING: Only valid within the Actor itself, so do not close over it and publish it to other threads!

    akka.actor.ActorContext is the Scala API. getContext returns a akka.actor.UntypedActorContext, which is the Java API of the actor context.

    Definition Classes
    Actor
  17. def deleteMessages(toSequenceNr: Long, permanent: Boolean): Unit

    Deletes all persistent messages with sequence numbers less than or equal toSequenceNr.

    Deletes all persistent messages with sequence numbers less than or equal toSequenceNr. If permanent is set to false, the persistent messages are marked as deleted in the journal, otherwise they permanently deleted from the journal.

    toSequenceNr

    upper sequence number bound of persistent messages to be deleted.

    permanent

    if false, the message is marked as deleted, otherwise it is permanently deleted.

    Definition Classes
    ProcessorImpl
  18. def deleteMessages(toSequenceNr: Long): Unit

    Permanently deletes all persistent messages with sequence numbers less than or equal toSequenceNr.

    Permanently deletes all persistent messages with sequence numbers less than or equal toSequenceNr.

    toSequenceNr

    upper sequence number bound of persistent messages to be deleted.

    Definition Classes
    ProcessorImpl
  19. def deleteSnapshot(sequenceNr: Long, timestamp: Long): Unit

    Deletes a snapshot identified by sequenceNr and timestamp.

    Deletes a snapshot identified by sequenceNr and timestamp.

    Definition Classes
    Snapshotter
  20. def deleteSnapshots(criteria: SnapshotSelectionCriteria): Unit

    Deletes all snapshots matching criteria.

    Deletes all snapshots matching criteria.

    Definition Classes
    Snapshotter
  21. def deliver(destination: ActorPath, deliveryIdToMessage: (Long) ⇒ Any): Unit

    Scala API: Send the message created by the deliveryIdToMessage function to the destination actor.

    Scala API: Send the message created by the deliveryIdToMessage function to the destination actor. It will retry sending the message until the delivery is confirmed with #confirmDelivery. Correlation between deliver and confirmDelivery is performed with the deliveryId that is provided as parameter to the deliveryIdToMessage function. The deliveryId is typically passed in the message to the destination, which replies with a message containing the same deliveryId.

    The deliveryId is a strictly monotonically increasing sequence number without gaps. The same sequence is used for all destinations of the actor, i.e. when sending to multiple destinations the destinations will see gaps in the sequence if no translation is performed.

    During recovery this method will not send out the message, but it will be sent later if no matching confirmDelivery was performed.

    This method will throw AtLeastOnceDelivery.MaxUnconfirmedMessagesExceededException if numberOfUnconfirmed is greater than or equal to #maxUnconfirmedMessages.

  22. def ensuring(cond: (AtLeastOnceDelivery) ⇒ Boolean, msg: ⇒ Any): AtLeastOnceDelivery

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to Ensuring[AtLeastOnceDelivery] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  23. def ensuring(cond: (AtLeastOnceDelivery) ⇒ Boolean): AtLeastOnceDelivery

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to Ensuring[AtLeastOnceDelivery] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  24. def ensuring(cond: Boolean, msg: ⇒ Any): AtLeastOnceDelivery

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to Ensuring[AtLeastOnceDelivery] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  25. def ensuring(cond: Boolean): AtLeastOnceDelivery

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to Ensuring[AtLeastOnceDelivery] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  26. final def eq(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  27. def equals(arg0: Any): Boolean

    Definition Classes
    AnyRef → Any
  28. def finalize(): Unit

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  29. def formatted(fmtstr: String): String

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to StringFormat performed by method any2stringfmt in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  30. final def getClass(): Class[_]

    Definition Classes
    AnyRef → Any
  31. def getDeliverySnapshot: AtLeastOnceDeliverySnapshot

    Full state of the AtLeastOnceDelivery.

    Full state of the AtLeastOnceDelivery. It can be saved with PersistentActor#saveSnapshot. During recovery the snapshot received in SnapshotOffer should be set with #setDeliverySnapshot.

    The AtLeastOnceDeliverySnapshot contains the full delivery state, including unconfirmed messages. If you need a custom snapshot for other parts of the actor state you must also include the AtLeastOnceDeliverySnapshot. It is serialized using protobuf with the ordinary Akka serialization mechanism. It is easiest to include the bytes of the AtLeastOnceDeliverySnapshot as a blob in your custom snapshot.

  32. def hashCode(): Int

    Definition Classes
    AnyRef → Any
  33. final def isInstanceOf[T0]: Boolean

    Definition Classes
    Any
  34. def lastSequenceNr: Long

    Highest received sequence number so far or 0L if this actor hasn't received a persistent message yet.

    Highest received sequence number so far or 0L if this actor hasn't received a persistent message yet. Usually equal to the sequence number of currentPersistentMessage (unless a receiver implementation is about to re-order persistent messages using stash() and unstash()).

    Definition Classes
    Recovery
  35. def loadSnapshot(persistenceId: String, criteria: SnapshotSelectionCriteria, toSequenceNr: Long): Unit

    Definition Classes
    Snapshotter
  36. def maxUnconfirmedMessages: Int

    Maximum number of unconfirmed messages that this actor is allowed to hold in memory.

    Maximum number of unconfirmed messages that this actor is allowed to hold in memory. If this number is exceed #deliver will not accept more messages and it will throw AtLeastOnceDelivery.MaxUnconfirmedMessagesExceededException.

    The default value can be configured with the akka.persistence.at-least-once-delivery.max-unconfirmed-messages configuration key. This method can be overridden by implementation classes to return non-default values.

  37. final def ne(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  38. final def notify(): Unit

    Definition Classes
    AnyRef
  39. final def notifyAll(): Unit

    Definition Classes
    AnyRef
  40. def numberOfUnconfirmed: Int

    Number of messages that have not been confirmed yet.

  41. def persistenceId: String

    Persistence id.

    Persistence id. Defaults to this persistent-actors's path and can be overridden.

    Definition Classes
    ProcessorRecovery
  42. def postRestart(reason: Throwable): Unit

    User overridable callback: By default it calls preStart().

    User overridable callback: By default it calls preStart().

    reason

    the Throwable that caused the restart to happen

    Is called right AFTER restart on the newly created Actor to allow reinitialization after an Actor crash.

    Definition Classes
    Actor
    Annotations
    @throws( classOf[Exception] )
  43. def postStop(): Unit

    Overridden callback.

    Overridden callback. Prepends all messages in the stash to the mailbox and clears the stash. Must be called when overriding this method, otherwise stashed messages won't be propagated to DeadLetters when actor stops.

    Definition Classes
    UnrestrictedStashActor
  44. def preRestart(reason: Throwable, message: Option[Any]): Unit

    User-overridable callback.

    User-overridable callback. Called before a processor is restarted. Default implementation sends a Recover(lastSequenceNr) message to self if message is defined, Recover() otherwise.

    reason

    the Throwable that caused the restart to happen

    message

    optionally the current message the actor processed when failing, if applicable

    Is called on a crashed Actor right BEFORE it is restarted to allow clean up of resources before Actor is terminated.

    Definition Classes
    ProcessorImpl → UnrestrictedStashActor
  45. def preRestartDefault(reason: Throwable, message: Option[Any]): Unit

    Calls preRestart and then super.preRestart().

    Calls preRestart and then super.preRestart(). If processor implementation classes want to opt out from stopping child actors, they should override this method and call preRestart only.

    Definition Classes
    ProcessorImpl
  46. def preStart(): Unit

    User-overridable callback.

    User-overridable callback. Called when a processor is started. Default implementation sends a Recover() to self.

    Definition Classes
    ProcessorImpl → Actor
    Annotations
    @throws( classOf[Exception] )
  47. def recoveryFinished: Boolean

    Returns true if this processor has successfully finished recovery.

    Returns true if this processor has successfully finished recovery.

    Definition Classes
    ProcessorImpl
  48. def recoveryRunning: Boolean

    Returns true if this processor is currently recovering.

    Returns true if this processor is currently recovering.

    Definition Classes
    ProcessorImpl
  49. def redeliverInterval: FiniteDuration

    Interval between redelivery attempts.

    Interval between redelivery attempts.

    The default value can be configured with the akka.persistence.at-least-once-delivery.redeliver-interval configuration key. This method can be overridden by implementation classes to return non-default values.

  50. def saveSnapshot(snapshot: Any): Unit

    Saves a snapshot of this snapshotter's state.

    Saves a snapshot of this snapshotter's state. If saving succeeds, this snapshotter will receive a SaveSnapshotSuccess message, otherwise a SaveSnapshotFailure message.

    Definition Classes
    Snapshotter
  51. implicit final val self: ActorRef

    The 'self' field holds the ActorRef for this actor.

    The 'self' field holds the ActorRef for this actor.

    Can be used to send messages to itself:

    self ! message
    

    Definition Classes
    Actor
  52. final def sender(): ActorRef

    The reference sender Actor of the last received message.

    The reference sender Actor of the last received message. Is defined if the message was sent from another Actor, else deadLetters in akka.actor.ActorSystem.

    WARNING: Only valid within the Actor itself, so do not close over it and publish it to other threads!

    Definition Classes
    Actor
  53. def setDeliverySnapshot(snapshot: AtLeastOnceDeliverySnapshot): Unit

    If snapshot from #getDeliverySnapshot was saved it will be received during recovery in a SnapshotOffer message and should be set with this method.

  54. def snapshotSequenceNr: Long

    Returns lastSequenceNr.

    Returns lastSequenceNr.

    Definition Classes
    RecoverySnapshotter
  55. def snapshotterId: String

    Returns persistenceId.

    Returns persistenceId.

    Definition Classes
    ProcessorImpl → Snapshotter
  56. def stash(): Unit

    Adds the current message (the message that the actor received last) to the actor's stash.

    Adds the current message (the message that the actor received last) to the actor's stash.

    Definition Classes
    StashSupport
    Exceptions thrown
    IllegalStateException

    if the same message is stashed more than once

    StashOverflowException

    in case of a stash capacity violation

  57. def supervisorStrategy: SupervisorStrategy

    User overridable definition the strategy to use for supervising child actors.

    User overridable definition the strategy to use for supervising child actors.

    Definition Classes
    Actor
  58. final def synchronized[T0](arg0: ⇒ T0): T0

    Definition Classes
    AnyRef
  59. def toString(): String

    Definition Classes
    AnyRef → Any
  60. def unhandled(message: Any): Unit

    User overridable callback.

    User overridable callback.

    Is called when a message isn't handled by the current behavior of the actor by default it fails with either a akka.actor.DeathPactException (in case of an unhandled akka.actor.Terminated message) or publishes an akka.actor.UnhandledMessage to the actor's system's akka.event.EventStream

    Definition Classes
    ProcessorImpl → Actor
  61. def unstashAll(): Unit

    Prepends all messages in the stash to the mailbox, and then clears the stash.

    Prepends all messages in the stash to the mailbox, and then clears the stash.

    Messages from the stash are enqueued to the mailbox until the capacity of the mailbox (if any) has been reached. In case a bounded mailbox overflows, a MessageQueueAppendFailedException is thrown.

    The stash is guaranteed to be empty after calling unstashAll().

    Definition Classes
    StashSupport
  62. final def wait(): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  63. final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  64. final def wait(arg0: Long): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  65. def warnAfterNumberOfUnconfirmedAttempts: Int

    After this number of delivery attempts a AtLeastOnceDelivery.UnconfirmedWarning message will be sent to self.

    After this number of delivery attempts a AtLeastOnceDelivery.UnconfirmedWarning message will be sent to self. The count is reset after a restart.

    The default value can be configured with the akka.persistence.at-least-once-delivery.warn-after-number-of-unconfirmed-attempts configuration key. This method can be overridden by implementation classes to return non-default values.

  66. def [B](y: B): (AtLeastOnceDelivery, B)

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to ArrowAssoc[AtLeastOnceDelivery] performed by method any2ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Shadowed Implicit Value Members

  1. val self: Any

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to StringAdd performed by method any2stringadd in scala.Predef.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (atLeastOnceDelivery: StringAdd).self
    Definition Classes
    StringAdd
  2. val self: Any

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to StringFormat performed by method any2stringfmt in scala.Predef.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (atLeastOnceDelivery: StringFormat).self
    Definition Classes
    StringFormat

Deprecated Value Members

  1. implicit def currentPersistentMessage: Option[Persistent]

    Returns the current persistent message if there is any.

    Returns the current persistent message if there is any.

    Definition Classes
    Recovery
    Annotations
    @deprecated
    Deprecated

    (Since version 2.3.4) currentPersistentMessage will be removed, sequence number can be retrieved with lastSequenceNr.

  2. def deleteMessage(sequenceNr: Long, permanent: Boolean): Unit

    Deletes a persistent message identified by sequenceNr.

    Deletes a persistent message identified by sequenceNr. If permanent is set to false, the persistent message is marked as deleted in the journal, otherwise it is permanently deleted from the journal. A deleted message is not replayed during recovery. This method is usually called inside preRestartProcessor when a persistent message caused an exception. Processors that want to re-receive that persistent message during recovery should not call this method.

    sequenceNr

    sequence number of the persistent message to be deleted.

    permanent

    if false, the message is marked as deleted, otherwise it is permanently deleted.

    Definition Classes
    ProcessorImpl
    Annotations
    @deprecated
    Deprecated

    (Since version 2.3.4) deleteMessage(sequenceNr) will be removed. Instead, validate before persist, and use deleteMessages for pruning.

  3. def deleteMessage(sequenceNr: Long): Unit

    Marks a persistent message, identified by sequenceNr, as deleted.

    Marks a persistent message, identified by sequenceNr, as deleted. A message marked as deleted is not replayed during recovery. This method is usually called inside preRestartProcessor when a persistent message caused an exception. Processors that want to re-receive that persistent message during recovery should not call this method.

    sequenceNr

    sequence number of the persistent message to be deleted.

    Definition Classes
    ProcessorImpl
    Annotations
    @deprecated
    Deprecated

    (Since version 2.3.4) deleteMessage(sequenceNr) will be removed. Instead, validate before persist, and use deleteMessages for pruning.

  4. def getCurrentPersistentMessage: Persistent

    Java API: returns the current persistent message or null if there is none.

    Java API: returns the current persistent message or null if there is none.

    Definition Classes
    Recovery
    Annotations
    @deprecated
    Deprecated

    (Since version 2.3.4) getCurrentPersistentMessage will be removed, sequence number can be retrieved with lastSequenceNr.

  5. def processorId: String

    Processor id.

    Processor id. Defaults to this processor's path and can be overridden.

    Definition Classes
    ProcessorImpl → Recovery
    Annotations
    @deprecated
    Deprecated

    (Since version 2.3.4) Override persistenceId: String instead. Processor will be removed.

  6. def x: AtLeastOnceDelivery

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to ArrowAssoc[AtLeastOnceDelivery] performed by method any2ArrowAssoc in scala.Predef.
    Shadowing
    This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
    To access this member you can use a type ascription:
    (atLeastOnceDelivery: ArrowAssoc[AtLeastOnceDelivery]).x
    Definition Classes
    ArrowAssoc
    Annotations
    @deprecated
    Deprecated

    (Since version 2.10.0) Use leftOfArrow instead

  7. def x: AtLeastOnceDelivery

    Implicit information
    This member is added by an implicit conversion from AtLeastOnceDelivery to Ensuring[AtLeastOnceDelivery] performed by method any2Ensuring in scala.Predef.
    Shadowing
    This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
    To access this member you can use a type ascription:
    (atLeastOnceDelivery: Ensuring[AtLeastOnceDelivery]).x
    Definition Classes
    Ensuring
    Annotations
    @deprecated
    Deprecated

    (Since version 2.10.0) Use resultOfEnsuring instead

Inherited from Processor

Inherited from ProcessorImpl

Inherited from Recovery

Inherited from StashFactory

Inherited from Stash

Inherited from UnrestrictedStash

Inherited from StashSupport

Inherited from Snapshotter

Inherited from Actor

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from AtLeastOnceDelivery to StringAdd

Inherited by implicit conversion any2stringfmt from AtLeastOnceDelivery to StringFormat

Inherited by implicit conversion any2ArrowAssoc from AtLeastOnceDelivery to ArrowAssoc[AtLeastOnceDelivery]

Inherited by implicit conversion any2Ensuring from AtLeastOnceDelivery to Ensuring[AtLeastOnceDelivery]

Ungrouped