ActorModel.NET

A lightweight Actor Model for .NET, which supports persistence, sleeping and on-demand restoring.

Properties:

• Isolated State: State kept outside of Actor definition
• Support Persistence Layer: The state would be persisted after any change in state by a defined delay
• Support Sleep & Restore: Actors will be automatically persisted and disposed after a defined period of inactivity to release the RAM. Then, they will be automatically restored from the persistence layer on demand.

How to use

Define Actor Definition (State and Behavior) by implementing the interface IActor<TState>.
In actor definition, you need to declare:

• State Type TState
• State initial value (by implementing InitialState())
• Actor Behaviour (by implementing the interface IActorBehavior<TState> and its factory in Behaviour())

// Actor Definition
public class MyActor : IActor<ActorState>
{
    // State Initial value
    public ActorState InitialState() => new ActorState(4);
    
    // Behaviour Factory
    public IActorBehavior<ActorState> Behaviour() => new ActorBehaviour();
}

// Actor State
public record ActorState(int IntValue);

// Actor Behaviour
public class ActorBehaviour : IActorBehavior<ActorState>
{
    public ActorState Handle(MessageEnvelope envelope, ActorState state)
    {
        switch (envelope.Message)
        {
            case AddValue message:
                return new ActorState(state.IntValue + message.IntValue);
            case Ping message:
                envelope.Responde(new Pong(state.IntValue));
                return state;
        }
        return state;
    }
}

Then, you need to create an ActorSystem instance and keep it as a singleton instance. You need to implement the IPersistence interface for the persistence layer. Also, you can customise the configuration by providing an ActorSystemConfiguration configuration class.

// Create Instance of ActorSystem
using var actorSystem = new ActorSystem(logger, persistence, configuration);

After creating ActorSystem instance and actor definitions, it's time to register Actor definitions in the system:

// Register Actors
actorSystem.Register<MyActort1>();
actorSystem.Register(new MyActor2(...));

Now, you can Create (Spawn) Actor / Send message / Get sate:

// Spawn (Create) and Actor
var actor1 = actorSystem.Spawn<ActorTest, ActorState>(new GuidActorIdentity(Guid.NewGuid()));

// Send a message to the actor
actor1.Send(new AddValue(13));

// Get Sate of the Actor
var state1 = await actor1.GetState(m => m.IntValue);

// Get / Restore the Actor
var actor1 = actorSystem.Get<ActorTest, ActorState>(identity);