Struct hannibal::Broker

pub struct Broker<T: Message<Result = ()>> { /* private fields */ }

Message broker is used to support publishing and subscribing to messages.

Examples

use hannibal::*;
use std::time::Duration;

#[message]
#[derive(Clone)]
struct MyMsg(&'static str);

#[message(result = "String")]
struct GetValue;

#[derive(Default)]
struct MyActor(String);

#[async_trait::async_trait]
impl Actor for MyActor {
    async fn started(&mut self, ctx: &mut Context<Self>) -> Result<()>  {
        ctx.subscribe::<MyMsg>().await;
        Ok(())
    }
}

#[async_trait::async_trait]
impl Handler<MyMsg> for MyActor {
    async fn handle(&mut self, _ctx: &mut Context<Self>, msg: MyMsg) {
        self.0 += msg.0;
    }
}

#[async_trait::async_trait]
impl Handler<GetValue> for MyActor {
    async fn handle(&mut self, _ctx: &mut Context<Self>, _msg: GetValue) -> String {
        self.0.clone()
    }
}

#[hannibal::main]
async fn main() -> Result<()> {
    let mut addr1 = MyActor::start_default().await?;
    let mut addr2 = MyActor::start_default().await?;

    Broker::from_registry().await?.publish(MyMsg("a"));
    Broker::from_registry().await?.publish(MyMsg("b"));

    sleep(Duration::from_secs(1)).await; // Wait for the messages

    assert_eq!(addr1.call(GetValue).await?, "ab");
    assert_eq!(addr2.call(GetValue).await?, "ab");
    Ok(())
}

Trait Implementations

impl<T: Message<Result = ()>> Actor for Broker<T>

const NAME: &'static str

fn started<'life0, 'life1, 'async_trait>(
    &'life0 mut self,
    ctx: &'life1 mut Context<Self>
) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>> where
    'life0: 'async_trait,
    'life1: 'async_trait,
    Self: 'async_trait, 

Called when the actor is first started.

fn stopped<'life0, 'life1, 'async_trait>(
    &'life0 mut self,
    ctx: &'life1 mut Context<Self>
) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>> where
    'life0: 'async_trait,
    'life1: 'async_trait,
    Self: 'async_trait, 

Called after an actor is stopped.

fn start_default<'async_trait>(
) -> Pin<Box<dyn Future<Output = Result<Addr<Self>>> + Send + 'async_trait>> where
    Self: Default,
    Self: 'async_trait, 

Construct and start a new actor, returning its address.

fn start<'async_trait>(
    self
) -> Pin<Box<dyn Future<Output = Result<Addr<Self>>> + Send + 'async_trait>> where
    Self: 'async_trait, 

Start a new actor, returning its address.

fn name(&self) -> Cow<'static, str>

impl<T: Message<Result = ()>> Default for Broker<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T: Message<Result = ()>> Service for Broker<T>

fn from_registry<'async_trait>(
) -> Pin<Box<dyn Future<Output = Result<Addr<Self>>> + Send + 'async_trait>> where
    Self: Send + 'async_trait,