is the
to the actor to which all messages will be forwarded.
ActorPath
can point to a local or remote actor, but the tunnel endpoint will be
deployed remotely on the node where the target actor lives.targetPath
is the ACK timeout after which all outstanding messages will be resent. There is no limit on the queue size or the number of retries.
is an optional interval between connection attempts.
It is also used as the interval between receiving a Terminated
for the tunnel and
attempting to reconnect to the target actor. The minimum recommended value for this is
the value of the configuration setting akka.remote.retry-gate-closed-for
. Use None
to never reconnect after a disconnection.
is an optional maximum number of attempts to connect to the
target actor. Use None
for no limit. If reconnectAfter
is None
this value is ignored.
This extractor is just convenience for matching a (S, S) pair, including a reminder what the new state is.
This extractor is just convenience for matching a (S, S) pair, including a reminder what the new state is.
This case object is received in case of a state timeout.
This case object is received in case of a state timeout.
Can be overridden to intercept calls to postRestart
.
Can be overridden to intercept calls to postStop
.
Can be overridden to intercept calls to preRestart
.
Can be overridden to intercept calls to preStart
.
INTERNAL API.
Cancel named timer, ensuring that the message is not subsequently delivered (no race).
Cancel named timer, ensuring that the message is not subsequently delivered (no race).
of the timer to cancel
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.
Retrieve current rolling log in oldest-first order.
Retrieve current rolling log in oldest-first order. The log is filled with each incoming event before processing by the user supplied state handler. The log entries are lost when this actor is restarted.
Sends the supplied message to all current listeners using the provided sender() as sender.
Sends the supplied message to all current listeners using the provided sender() as sender.
Produce transition to other state.
Produce transition to other state. Return this from a state function in order to effect the transition.
state designator for the next state
state transition descriptor
Verify existence of initial state and setup timers.
Verify existence of initial state and setup timers. This should be the last call within the constructor, or akka.actor.Actor#preStart and akka.actor.Actor#postRestart
Inquire whether the named timer is still active.
Inquire whether the named timer is still active. Returns true unless the timer does not exist, has previously been canceled or if it was a single-shot timer whose message was already received.
Chain this into the receive function.
Chain this into the receive function.
def receive = listenerManagement orElse
By default FSM.Failure is logged at error level and other reason types are not logged.
By default FSM.Failure is logged at error level and other reason types are not logged. It is possible to override this behavior.
Returns the next retry interval duration.
Returns the next retry interval duration. By default each interval is the same, reconnectAfter.
Return next state data (available in onTransition handlers)
Return next state data (available in onTransition handlers)
Set handler which is called upon termination of this FSM actor.
Set handler which is called upon termination of this FSM actor. Calling this method again will overwrite the previous contents.
Set handler which is called upon each state transition, i.e.
Set handler which is called upon each state transition, i.e. not when staying in the same state. This may use the pair extractor defined in the FSM companion object like so:
onTransition { case Old -> New => doSomething }
It is also possible to supply a 2-ary function object:
onTransition(handler _) private def handler(from: S, to: S) { ... }
The underscore is unfortunately necessary to enable the nicer syntax shown above (it uses the implicit conversion total2pf under the hood).
Multiple handlers may be installed, and every one of them will be called, not only the first one matching.
User overridable callback: By default it calls preStart()
.
User overridable callback: By default it calls preStart()
.
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.
Call onTermination
hook; if you want to retain this behavior when
overriding make sure to call super.postStop()
.
Call onTermination
hook; if you want to retain this behavior when
overriding make sure to call super.postStop()
.
Please note that this method is called by default from preRestart()
,
so override that one if onTermination
shall not be called during
restart.
User overridable callback: By default it disposes of all children and then calls postStop()
.
User overridable callback: By default it disposes of all children and then calls postStop()
.
the Throwable that caused the restart to happen
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.
User overridable callback.
User overridable callback.
Is called when an Actor is started. Actors are automatically started asynchronously when created. Empty default implementation.
This defines the initial actor behavior, it must return a partial function with the actor logic.
Reset backoff interval.
Reset backoff interval.
This and nextBackoff are meant to be implemented by subclasses.
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
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!
Set state timeout explicitly.
Set state timeout explicitly. This method can safely be used from within a state handler.
Schedule named timer to deliver message after given delay, possibly repeating.
Schedule named timer to deliver message after given delay, possibly repeating. Any existing timer with the same name will automatically be canceled before adding the new timer.
identifier to be used with cancelTimer()
message to be delivered
delay of first message delivery and between subsequent messages
send once if false, scheduleAtFixedRate if true
current state descriptor
Set initial state.
Set initial state. Call this method from the constructor before the #initialize method. If different state is needed after a restart this method, followed by #initialize, can be used in the actor life cycle hooks akka.actor.Actor#preStart and akka.actor.Actor#postRestart.
initial state designator
initial state data
state timeout for the initial state, overriding the default timeout for that state
Return current state data (i.e.
Return current state data (i.e. object of type D)
Return current state name (i.e.
Return current state name (i.e. object of type S)
Produce "empty" transition descriptor.
Produce "empty" transition descriptor. Return this from a state function when no state change is to be effected.
descriptor for staying in current state
Produce change descriptor to stop this FSM actor including specified reason.
Produce change descriptor to stop this FSM actor including specified reason.
Produce change descriptor to stop this FSM actor including specified reason.
Produce change descriptor to stop this FSM actor including specified reason.
Produce change descriptor to stop this FSM actor with reason "Normal".
Produce change descriptor to stop this FSM actor with reason "Normal".
User overridable definition the strategy to use for supervising child actors.
User overridable definition the strategy to use for supervising child actors.
Convenience wrapper for using a total function instead of a partial function literal.
Convenience wrapper for using a total function instead of a partial function literal. To be used with onTransition.
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
Insert a new StateFunction at the end of the processing chain for the given state.
Insert a new StateFunction at the end of the processing chain for the given state. If the stateTimeout parameter is set, entering this state without a differing explicit timeout setting will trigger a StateTimeout event; the same is true when using #stay.
designator for the state
default state timeout for this state
partial function describing response to input
Set handler which is called upon reception of unhandled messages.
Set handler which is called upon reception of unhandled messages. Calling this method again will overwrite the previous contents.
The current state may be queried using
.
stateName
(reliableProxy: ArrowAssoc[ReliableProxy]).->(y)
A ReliableProxy is a means to wrap a remote actor reference in order to obtain certain improved delivery guarantees:
These guarantees are valid for the communication between the two end-points of the reliable “tunnel”, which usually spans an unreliable network.
Note that the ReliableProxy guarantees at-least-once, not exactly-once, delivery.
Delivery from the remote end-point to the target actor is still subject to in-JVM delivery semantics (i.e. not strictly guaranteed due to possible OutOfMemory situations or other VM errors).
You can create a reliable connection like this:
In Scala:
or in Java:
Please note: the tunnel is uni-directional, and original sender information is retained, hence replies by the wrapped target reference will go back in the normal “unreliable” way unless also secured by a ReliableProxy from the remote end.
Message Types
This actor is an akka.actor.FSM, hence it offers the service of transition callbacks to those actors which subscribe using the
andSubscribeTransitionCallBack
messages; see akka.actor.FSM for more documentation. The proxy will transition into ReliableProxy.Active state when ACKs are outstanding and return to the ReliableProxy.Idle state when every message send so far has been confirmed by the peer end-point.UnsubscribeTransitionCallBack
The initial state of the proxy is ReliableProxy.Connecting. In this state the proxy will repeatedly send akka.actor.Identify messages to
ActorSelection(targetPath)
in order to obtain a newActorRef
for the target. When an akka.actor.ActorIdentity for the target is received a new tunnel will be created, a ReliableProxy.TargetChanged message containing the targetActorRef
will be sent to the proxy's transition subscribers and the proxy will transition into either the ReliableProxy.Idle or ReliableProxy.Active state, depending if there are any outstanding messages that need to be delivered. IfmaxConnectAttempts
is defined this actor will stop itself afterIdentify
is sentmaxConnectAttempts
times.While in the
Idle
orActive
states, if a communication failure causes the tunnel to terminate via Remote Deathwatch the proxy will transition into the ReliableProxy.Connecting state as described above. After reconnectingTargetChanged
will be sent only if the targetActorRef
has changed.If this actor is stopped and it still has outstanding messages a ReliableProxy.ProxyTerminated message will be sent to the transition subscribers. It contains an
Unsent
object with the outstanding messages.If an ReliableProxy.Unsent message is sent to this actor the messages contained within it will be relayed through the tunnel to the target.
Any other message type sent to this actor will be delivered via a remote-deployed child actor to the designated target.
Failure Cases
All failures of either the local or the remote end-point are escalated to the parent of this actor; there are no specific error cases which are predefined.
Arguments
See the constructor below for the arguments for this actor. However, prefer using akka.contrib.pattern.ReliableProxy#props to this actor's constructor.