mediatrix

Strongly typed, extensible event mediator. For more info and explanation, please see the docs.

Usage

Sync

use mediatrix::synchronous::basic::*;

struct UserMessageRequest {
    msg: String,
    priority: u8,
}

#[derive(Debug)]
enum NotifyEvent {
    Ignore,
    SendEmail(String),
    SendTextMessage(String),
}

impl RequestHandler<UserMessageRequest, NotifyEvent> for BasicMediator<NotifyEvent> {
    fn handle(&self, req: UserMessageRequest) {
        match req.priority {
            0 => self.publish(NotifyEvent::Ignore),
            1..=5 => self.publish(NotifyEvent::SendEmail(req.msg)),
            _ => self.publish(NotifyEvent::SendTextMessage(req.msg)),
        };
    }
}

let mediator = BasicMediator::<NotifyEvent>::builder()
    .add_listener(move |ev: &NotifyEvent| {
        if let NotifyEvent::Ignore = ev {
            println!("Ignored some Message")
        }
    })
    .add_listener(move |ev: &NotifyEvent| {
        if let NotifyEvent::SendEmail(msg) = ev {
            println!("Send Email with Message: {}", msg)
        }
    })
    .add_listener(move |ev: &NotifyEvent| {
        if let NotifyEvent::SendTextMessage(msg) = ev {
            println!("Send SMS with Message: {}", msg)
        }
    })
    .build();

mediator.send(UserMessageRequest {
    msg: String::from("Hello World"),
    priority: 0,
});

mediator.send(UserMessageRequest {
    msg: String::from("Is Rust Memory Safe?"),
    priority: 2,
});

mediator.send(UserMessageRequest {
    msg: String::from("New Rust Version"),
    priority: 8,
});

// Prints: Ignored some Message
mediator.next().ok();
// Prints: Send Email with Message: Is Rust Memory Safe?
mediator.next().ok();
// Prints: Send SMS with Message: New Rust Version
mediator.next().ok();

Async

use mediatrix::asynchronous::basic::*;
use async_trait::async_trait;

struct UserMessageRequest {
    msg: String,
    priority: u8,
}

#[derive(Debug)]
enum NotifyEvent {
    Ignore,
    SendEmail(String),
    SendTextMessage(String),
}

#[async_trait]
impl AsyncRequestHandler<UserMessageRequest, NotifyEvent> for BasicAsyncMediator<NotifyEvent> {
    async fn handle(&self, req: UserMessageRequest) {
        match req.priority {
            0 => self.publish(NotifyEvent::Ignore).await,
            1..=5 => self.publish(NotifyEvent::SendEmail(req.msg)).await,
            _ => self.publish(NotifyEvent::SendTextMessage(req.msg)).await,
        };
    }
}

let async_mediator = BasicAsyncMediator::<NotifyEvent>::builder()
    .add_listener(move |ev: &NotifyEvent| {
        if let NotifyEvent::Ignore = ev {
            println!("Ignored some Message")
        }
    })
    .add_listener(move |ev: &NotifyEvent| {
        if let NotifyEvent::SendEmail(msg) = ev {
            println!("Send Email with Message: {}", msg)
        }
    })
    .add_listener(move |ev: &NotifyEvent| {
        if let NotifyEvent::SendTextMessage(msg) = ev {
            println!("Send SMS with Message: {}", msg)
        }
    })
    .build();

async_std::task::block_on(async {
    async_mediator.send(UserMessageRequest {
        msg: String::from("Hello World"),
        priority: 0,
    }).await;

    async_mediator.send(UserMessageRequest {
        msg: String::from("Is Rust Memory Safe?"),
        priority: 2,
    }).await;

    async_mediator.send(UserMessageRequest {
        msg: String::from("New Rust Version"),
        priority: 8,
    }).await;

    async_mediator.next().await.ok();
    async_mediator.next().await.ok();
    async_mediator.next().await.ok();
});

Features

• sync and async (use async feature) mediators
• CxAwareMediator (use async feature, carries a struct of your choice)
• compiler-baked typing
• extensible architecture

Todo

• internally, make builders reuse other builders whose target is a comp. of this builder.

Contributions

Feel free to open an issue/PR explaining possible improvements or changes.

Help

Also, please do not hesitate and open an issue when needed. I am happy to help!