#actor-model #service #actix #async #message #async-api #tokio

serviceless

An simple actor model in rust, like actix

3 releases

0.1.2 Dec 15, 2023
0.1.1 Sep 12, 2023
0.1.0 Sep 11, 2023

#1437 in Asynchronous

MIT license

11KB
203 lines

Serviceless

Serviceless is an simple actor model in rust, like actix but simple and async.

Currently, this crate only use tokio as backend.

This crate is no unsafe code.

Usage

This crate provide API same like actix. But all api is async include handler.

Service

Service is a Actor in Actor Model.

We can impl an Service on an struct to delcare an Service.

pub struct Service0 {}

impl Service for Service0 {}

The Service provide hook named started and stopped, them all are async. Please use async_trait macros.

pub struct Service1 {}

#[async_trait]
impl Service for Service1 {
    async fn started(&mut self, _ctx: &mut Context<Self>) {
        println!("Started")
    }
}

Start Service

Start a service is very simple, only create it and call start method.

let svc = Service1 {};
svc.start();

Note: this function must call in async function or after async runtime initialized. If not, it will panic.

Stop and Pause

When a service started, we can call stop and pause method on context.

You can call these function in Service Hook or in Handler.

Handler and Mesaage

A service can sending an message to other service, or called by other service.

Message

To call other Service, we must declare an Message first.

Any type can be a message, only need impl Message trait on struct and define an result.

pub struct Messagep {}

pub struct MessageResult {}

impl Message for Message0 {
    type Result = MessageResult;
}

Handler

Impl Handler on service, we can make a service accept call from other service.

#[async_trait]
impl Handler<U8> for Service0 {
    async fn handler(&mut self, message: U8, _ctx: &mut Context<Self>) -> U8 {
        U8(message.0 + 2)
    }
}

Handler also an async function, please use async_trait macros.

Address

When we start an service, we can get an address. We also can get it from Context.

Call and Send

The address can make call or send.

  • Call means caller want to known the result.
    1. This is an async function
    2. When an service stop, caller will get ServiceStopped from Error.
    3. When an service pause, caller will get ServicePaused from Error.
  • Send means caller don't care the result, so
    1. This is an plain function
    2. When an service stop, caller will get ServiceStopped from Error.
    3. Caller can't known service paused

Dependencies

~2.3–8MB
~66K SLoC