//! More comprehensive example that aims to show more of `message` //! crate functionality. //! //! In this example, both `Handler` and `Notifiable` traits are implemented, //! as well as additional methods of an `Actor` trait. use messages::prelude::*; #[derive(Debug, Default)] pub struct Service { value: u64, } #[async_trait] impl Actor for Service { // `started` method will be invoked *before* the first message // will be received. async fn started(&mut self) { println!("Service was started"); } // `stopping` method will be invoked when the actor will be requested // to stop its execution. async fn stopping(&mut self) -> ActorAction { println!("Service is stopping"); // We could've ignored the stop request by returning `ActorAction::KeepRunning`. ActorAction::Stop } // `stopped` method will be invoked once actor is actually stopped. fn stopped(&mut self) { println!("Service has stopped"); } } // Type that we will use to send messages. #[derive(Debug)] pub struct Request(pub u64); #[async_trait] impl Handler for Service { type Result = u64; async fn handle(&mut self, input: Request, _: &Context) -> u64 { self.value + input.0 } } // Type that we will use for notifications. #[derive(Debug)] pub struct Notification(pub u64); // Unlike `Handler`, `Notifiable` trait doesn't have output. // It only serves one purpose: deliver a message to an actor. // No response is expected. #[async_trait] impl Notifiable for Service { async fn notify(&mut self, input: Notification, _: &Context) { self.value = input.0; } } impl Service { pub fn new() -> Self { Self::default() } } #[tokio::main] async fn main() { // Start a service. let mut address = Service::new().spawn(); // Send a notification. address.notify(Notification(10)).await.unwrap(); // Send a request and receive a response. let response: u64 = address.send(Request(1)).await.unwrap(); assert_eq!(response, 11); // Stop service. address.stop().await; // Wait for service to stop. address.wait_for_stop().await; // Ensure that actor is not running anymore. assert!(!address.connected()); }