final class ClusterSingletonProxy extends Actor with ActorLogging

The ClusterSingletonProxy works together with the akka.cluster.singleton.ClusterSingletonManager to provide a distributed proxy to the singleton actor.

The proxy can be started on every node where the singleton needs to be reached and used as if it were the singleton itself. It will then act as a router to the currently running singleton instance. If the singleton is not currently available, e.g., during hand off or startup, the proxy will buffer the messages sent to the singleton and then deliver them when the singleton is finally available. The size of the buffer is configurable and it can be disabled by using a buffer size of 0. When the buffer is full old messages will be dropped when new messages are sent via the proxy.

The proxy works by keeping track of the oldest cluster member. When a new oldest member is identified, e.g. because the older one left the cluster, or at startup, the proxy will try to identify the singleton on the oldest member by periodically sending an akka.actor.Identify message until the singleton responds with its akka.actor.ActorIdentity.

Note that this is a best effort implementation: messages can always be lost due to the distributed nature of the actors involved.

Source
ClusterSingletonProxy.scala
Linear Supertypes
ActorLogging, Actor, AnyRef, Any
Type Hierarchy
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Inherited
  1. ClusterSingletonProxy
  2. ActorLogging
  3. Actor
  4. AnyRef
  5. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Visibility
  1. Public
  2. Protected

Instance Constructors

  1. new ClusterSingletonProxy(singletonManagerPath: String, settings: ClusterSingletonProxySettings)

Type Members

  1. type Receive = PartialFunction[Any, Unit]
    Definition Classes
    Actor

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toany2stringadd[ClusterSingletonProxy] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (ClusterSingletonProxy, B)
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toArrowAssoc[ClusterSingletonProxy] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  6. def add(m: Member): Unit

    Adds new member if it has the right role.

    Adds new member if it has the right role.

    m

    New cluster member.

  7. val ageOrdering: Ordering[Member]
  8. def aroundPostRestart(reason: Throwable): Unit

    INTERNAL API.

    INTERNAL API.

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

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

    INTERNAL API.

    INTERNAL API.

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

    Attributes
    protected[akka]
    Definition Classes
    Actor
    Annotations
    @InternalApi()
  10. def aroundPreRestart(reason: Throwable, message: Option[Any]): Unit

    INTERNAL API.

    INTERNAL API.

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

    Attributes
    protected[akka]
    Definition Classes
    Actor
    Annotations
    @InternalApi()
  11. def aroundPreStart(): Unit

    INTERNAL API.

    INTERNAL API.

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

    Attributes
    protected[akka]
    Definition Classes
    Actor
    Annotations
    @InternalApi()
  12. def aroundReceive(receive: actor.Actor.Receive, msg: Any): Unit

    INTERNAL API.

    INTERNAL API.

    Can be overridden to intercept calls to this actor's current behavior.

    receive

    current behavior.

    msg

    current message.

    Attributes
    protected[akka]
    Definition Classes
    Actor
    Annotations
    @InternalApi()
  13. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  14. def buffer(msg: Any): Unit
  15. var buffer: MessageBuffer
  16. def cancelTimer(): Unit
  17. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @HotSpotIntrinsicCandidate() @native()
  18. val cluster: Cluster
  19. implicit val context: ActorContext

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

    Scala API: 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.AbstractActor.ActorContext, which is the Java API of the actor context.

    Definition Classes
    Actor
  20. def createIdentifyId(i: Int): String
  21. def ensuring(cond: (ClusterSingletonProxy) => Boolean, msg: => Any): ClusterSingletonProxy
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toEnsuring[ClusterSingletonProxy] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  22. def ensuring(cond: (ClusterSingletonProxy) => Boolean): ClusterSingletonProxy
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toEnsuring[ClusterSingletonProxy] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  23. def ensuring(cond: Boolean, msg: => Any): ClusterSingletonProxy
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toEnsuring[ClusterSingletonProxy] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  24. def ensuring(cond: Boolean): ClusterSingletonProxy
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toEnsuring[ClusterSingletonProxy] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  25. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  26. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  27. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  28. def handleInitial(state: CurrentClusterState): Unit
  29. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  30. var identifyCounter: Int
  31. var identifyId: String
  32. def identifySingleton(): Unit

    Discard old singleton ActorRef and send a periodic message to self to identify the singleton.

  33. var identifyTimer: Option[Cancellable]
  34. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  35. def log: LoggingAdapter
    Definition Classes
    ActorLogging
  36. def matchingRole(member: Member): Boolean
  37. var membersByAge: SortedSet[Member]
  38. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  39. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  40. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  41. 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])
  42. def postStop(): Unit

    User overridable callback.

    User overridable callback.

    Is called asynchronously after 'actor.stop()' is invoked. Empty default implementation.

    Definition Classes
    ClusterSingletonProxy → Actor
  43. def preRestart(reason: Throwable, message: Option[Any]): Unit

    Scala API: User overridable callback: By default it disposes of all children and then calls postStop().

    Scala API: User overridable callback: By default it disposes of all children and then calls postStop().

    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
    Actor
    Annotations
    @throws(classOf[Exception])
  44. def preStart(): Unit

    User overridable callback.

    User overridable callback.

    Is called when an Actor is started. Actors are automatically started asynchronously when created. Empty default implementation.

    Definition Classes
    ClusterSingletonProxy → Actor
  45. def receive: PartialFunction[Any, Unit]

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

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

    Definition Classes
    ClusterSingletonProxy → Actor
  46. def remove(m: Member): Unit

    Removes a member.

    Removes a member.

    m

    Cluster member to remove.

  47. 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
  48. def sendBuffered(): Unit
  49. 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
  50. var singleton: Option[ActorRef]
  51. val singletonPath: Array[String]
  52. 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
  53. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  54. def toString(): String
    Definition Classes
    AnyRef → Any
  55. def trackChange(block: () => Unit): Unit
  56. 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
    Actor
  57. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  58. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()
  59. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])

Deprecated Value Members

  1. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable]) @Deprecated
    Deprecated

    (Since version 9)

  2. def formatted(fmtstr: String): String
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toStringFormat[ClusterSingletonProxy] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @deprecated @inline()
    Deprecated

    (Since version 2.12.16) Use formatString.format(value) instead of value.formatted(formatString), or use the f"" string interpolator. In Java 15 and later, formatted resolves to the new method in String which has reversed parameters.

  3. def →[B](y: B): (ClusterSingletonProxy, B)
    Implicit
    This member is added by an implicit conversion from ClusterSingletonProxy toArrowAssoc[ClusterSingletonProxy] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @deprecated
    Deprecated

    (Since version 2.13.0) Use -> instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.

Inherited from ActorLogging

Inherited from Actor

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd fromClusterSingletonProxy to any2stringadd[ClusterSingletonProxy]

Inherited by implicit conversion StringFormat fromClusterSingletonProxy to StringFormat[ClusterSingletonProxy]

Inherited by implicit conversion Ensuring fromClusterSingletonProxy to Ensuring[ClusterSingletonProxy]

Inherited by implicit conversion ArrowAssoc fromClusterSingletonProxy to ArrowAssoc[ClusterSingletonProxy]

Ungrouped