atsapura/PostOffice

PostOffice

This library is a convinient API for the MailboxProcessor. It helps to build a simple actor model.

Creating a pure MailboxProcessor actor

open PostOffice

type Message =
    | Increment of int
    | Decrement of int

let applyMessage state msg =
    match msg with
    | Increment i -> state + i
    | Decrement i -> state - i

let actor = 0 |> Mailbox.buildAgent applyMessage

Then you can use Mailbox module to interact with your actor:

open PostOffice

let increment myActor =
    Increment 1 |> Mailbox.post myActor

let getCount myActor =
    Mailbox.get myActor

Building an actor network

Build your mailbox processor as shown above, add unique address to it and create a MailAgent That way you don't need to call Mailbox module directly

let [<Literal>] myAgentAddress = "address"
let myAgent = (myAgentAddress, []|> Mailbox.buildAgent applyMessage) |> MailAgent
do Increment 1 |> myAgent.Post
let count = myAgent.GetState()

When you have your agent(s), you can create a network

let network = new MailboxNetwork()
do network.RespawnBox myAgent
let myAgentInNetwork = network.Box<Message, int32>(myAgentAddress)

Lost messages

Sometimes you mess up your addresses or generic parameters and messages get lost. You can find the map with all of them in the dead box in your network like this:

let deadLetters = network.DeadLetters.GetState()