Actix is a rust actor framework.
- API Documentation (Development)
- API Documentation (Releases)
- Cargo package: actix
- Async/Sync actors.
- Actor communication in a local/thread context.
- Using Futures for asynchronous message handling.
- HTTP1/HTTP2 support (actix-web)
- Actor supervision.
- Typed messages (No
Any
type). Generic messages are allowed.
To use actix
, add this to your Cargo.toml
:
[dependencies]
actix = "0.3"
You may consider to check chat example.
In order to use actix you first need to create an System
.
extern crate actix;
fn main() {
let system = actix::System::new("test");
system.run();
}
Actix uses tokio event loop.
System::new()
call creates new event loop and starts System
actor.
system.run()
starts tokio event loop and will finish once the System
actor
receives SystemExit
message.
Let's create simple Actor.
In order to define an actor you need to define a struct and have it implement
the Actor
trait.
extern crate actix;
use actix::{msgs, Actor, Address, Arbiter, Context, System};
struct MyActor;
impl Actor for MyActor {
type Context = Context<Self>;
fn started(&mut self, ctx: &mut Self::Context) {
println!("I am alive!");
Arbiter::system().send(msgs::SystemExit(0));
}
}
fn main() {
let system = System::new("test");
let addr: Address<_> = MyActor.start();
system.run();
}
Spawning a new actor is achieved via the start
and create
methods of
Actor
trait. It provides several different ways of creating actors, for details check docs.
You can implement started
, stopping
and stopped
mthods of Actor trait,
started
method get called when actor starts and stopping
when actor finishes.
Check api documentation
for more information on actor lifecycle.
An Actor communicates with another Actor by sending an messages. In actix all messages are typed.
Let's define simple Sum
message with two usize
parameters and actor which will
accept this message and return sum of those two numbers.
extern crate actix;
extern crate futures;
use futures::{future, Future};
use actix::*;
// this is our Message
struct Sum(usize, usize);
// we have to define type of response for `Sum` message
impl ResponseType for Sum {
type Item = usize;
type Error = ();
}
// Actor definition
struct Summator;
impl Actor for Summator {
type Context = Context<Self>;
}
// now we need to define `MessageHandler` for `Sum` message.
impl Handler<Sum> for Summator {
fn handle(&mut self, msg: Sum, ctx: &mut Context<Self>) -> Response<Self, Sum> {
Self::reply(msg.0 + msg.1)
}
}
fn main() {
let system = System::new("test");
let addr: Address<_> = Summator.start();
// Address<A>::call() returns ActorFuture object, so we need to wait for result.
// ActorFuture makes sense within Actor execution context, but we can use
// Address<A>::call_fut() which return simple Future object.
let res = addr.call_fut(Sum(10, 5));
system.handle().spawn(res.then(|res| {
match res {
Ok(Ok(result)) => println!("SUM: {}", result),
_ => println!("Something wrong"),
}
Arbiter::system().send(msgs::SystemExit(0));
future::result(Ok(()))
}));
system.run();
}
All communications with actors go through Address
object. You can send
message
without waiting response or call
actor with specific message. ResponseType
trait defines response type for a message, Item
and Error
for value and error respectevily.
There are different types of addresses.
Address<A>
is an address
of an actor that runs in same arbiter (event loop). If actor is running in different
thread SyncAddress<A>
has to be used.
If you noticed, methods of Actor
and Handler
traits accept &mut self
, so you are welcome to
store anything in an actor and mutate it whenever you need.
Address object requires actor type, but if we just want to send specific message to
an actor that can handle message, we can use Subscriber
interface. Let's create
new actor that uses Subscriber
, also this example will show how to use standard future objects.
Also in this example we are going to use unstable proc_macro
rust's feature for message
and handler definitions
#![feature(proc_macro)]
extern crate actix;
use std::time::Duration;
use actix::*;
#[msg]
struct Ping { pub id: usize }
// Actor definition
struct Game {
counter: usize,
addr: Box<Subscriber<Ping>>
}
#[actor(Context<_>)]
impl Game {
#[simple(Ping)]
// simple message handler for Ping message
fn ping(&mut self, id: usize, ctx: &mut Context<Self>) {
self.counter += 1;
if self.counter > 10 {
Arbiter::system().send(msgs::SystemExit(0));
} else {
println!("Ping received {:?}", id);
// wait 100 nanos
ctx.run_later(Duration::new(0, 100), move |act, _| {
act.addr.send(Ping{id: id + 1});
});
}
}
}
fn main() {
let system = System::new("test");
// we need Subscriber object so we need to use different builder method
// which will allow to postpone actor creation
let _: Address<_> = Game::create(|ctx| {
// now we can get address of first actor and create second actor
let addr: Address<_> = ctx.address();
let addr2: Address<_> = Game{counter: 0, addr: addr.subscriber()}.start();
// lets start pings
addr2.send(Ping{id: 10});
// now we can finally create first actor
Game{counter: 0, addr: addr2.subscriber()}
});
system.run();
}
More information on signals handling is in signal module.
You may consider to check chat example. It provides basic example of networking client/server service.
You may consider to check fectl utility. It is written
with actix
and shows how to create networking application with relatevly complex interactions.
All contribution are welcome, if you have a feature request don't hesitate to open an issue!
This project is licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.