atomr_core/actor/
traits.rs

1//! Core `Actor` trait and message envelope.
2
3use async_trait::async_trait;
4
5use super::context::Context;
6use super::sender::Sender;
7use crate::supervision::SupervisorStrategy;
8
9/// Envelope that carries a user message plus a typed [`Sender`].
10///
11/// `M` is the actor's user message type. The [`Sender`] preserves the
12/// origin's identity end-to-end (no `Any::downcast` on reply paths) —
13/// see `docs/idiomatic-rust.md` (P-1) and Phase 1 of
14/// `docs/full-port-plan.md`.
15pub struct MessageEnvelope<M> {
16    pub message: M,
17    pub sender: Sender,
18}
19
20impl<M> MessageEnvelope<M> {
21    pub fn new(message: M) -> Self {
22        Self { message, sender: Sender::None }
23    }
24
25    /// Construct with a typed [`Sender`].
26    pub fn with_typed_sender(message: M, sender: Sender) -> Self {
27        Self { message, sender }
28    }
29}
30
31/// The user-facing `Actor` trait.
32///
33/// is expressed here as: each actor has an
34/// associated `Msg` type (typically an enum) and implements an async
35/// `handle` that matches on it.
36#[async_trait]
37pub trait Actor: Sized + Send + 'static {
38    type Msg: Send + 'static;
39
40    /// Process a single message.
41    async fn handle(&mut self, ctx: &mut Context<Self>, msg: Self::Msg);
42
43    /// Called once before the first message.
44    async fn pre_start(&mut self, _ctx: &mut Context<Self>) {}
45
46    /// Called after the actor has been stopped.
47    async fn post_stop(&mut self, _ctx: &mut Context<Self>) {}
48
49    /// Called when the actor is about to be restarted by the supervisor.
50    async fn pre_restart(&mut self, _ctx: &mut Context<Self>, _err: &str) {}
51
52    /// Called after a restart.
53    async fn post_restart(&mut self, _ctx: &mut Context<Self>, _err: &str) {}
54
55    /// Called when a watched actor terminates. The `path` argument is
56    /// the path of the actor that just stopped. Default is a no-op.
57    /// Implementations may translate this into a user-visible message
58    /// (the Python binding does this for `Terminated` events).
59    async fn on_terminated(&mut self, _ctx: &mut Context<Self>, _path: &super::path::ActorPath) {}
60
61    /// The supervisor strategy this actor applies to its own children.
62    fn supervisor_strategy(&self) -> SupervisorStrategy {
63        SupervisorStrategy::default()
64    }
65}
atomr_core/actor/traits.rs

atomr_core/actor/
traits.rs
