Supervision strategies

Actors have a place in their system's hierarchy trees. To manage failures done by the child actors, their parents/supervisors may decide to use specific supervisor strategies (see: Akka supervision) in order to react to the specific types of errors. In F# this may be configured using functions of the Strategy module:

• Strategy.OneForOne (decider : exn -> Directive) : SupervisorStrategy - returns a supervisor strategy applicable only to child actor which faulted during execution.
• Strategy.OneForOne (decider : exn -> Directive, ?retries : int, ?timeout : TimeSpan) : SupervisorStrategy - returns a supervisor strategy applicable only to child actor which faulted during execution. [retries] param defines a number of times, an actor could be restarted. If it's a negative value, there is not limit. [timeout] param defines a time window for number of retries to occur.
• OneForOne (decider : Expr<(exn -> Directive)>, ?retries : int, ?timeout : TimeSpan) : SupervisorStrategy - returns a supervisor strategy applicable only to child actor which faulted during execution. [retries] param defines a number of times, an actor could be restarted. If it's a negative value, there is not limit. [timeout] param defines a time window for number of retries to occur. Strategies created this way may be serialized and deserialized on remote nodes .
• Strategy.AllForOne (decider : exn -> Directive) : SupervisorStrategy - returns a supervisor strategy applicable to each supervised actor when any of them had faulted during execution.
• Strategy.AllForOne (decider : exn -> Directive, ?retries : int, ?timeout : TimeSpan) : SupervisorStrategy - returns a supervisor strategy applicable to each supervised actor when any of them had faulted during execution. [retries] param defines a number of times, an actor could be restarted. If it's a negative value, there is not limit. [timeout] param defines a time window for number of retries to occur.
• AllForOne (decider : Expr<(exn -> Directive)>, ?retries : int, ?timeout : TimeSpan) : SupervisorStrategy - returns a supervisor strategy applicable to each supervised actor when any of them had faulted during execution. [retries] param defines a number of times, an actor could be restarted. If it's a negative value, there is not limit. [timeout] param defines a time window for number of retries to occur. Strategies created this way may be serialized and deserialized on remote nodes .

Example:

let aref = 
    spawnOpt system "my-actor" { props (actorOf myFunc) with
        SupervisorStrategy = Strategy.OneForOne (fun error -> 
            match error with
            | :? ArithmeticException -> Directive.Escalate
            | _ -> SupervisorStrategy.DefaultDecider error ) }

let remoteRef = 
    spawne system "remote-actor" { propse <@ actorOf myFunc @> with
        SupervisorStrategy = (Strategy.OneForOne <@ fun error -> 
            match error with
            | :? ArithmeticException -> Directive.Escalate
            | _ -> SupervisorStrategy.DefaultDecider error ) @>);
        Deploy = Deploy (RemoteScope remoteNodeAddr) }