tokio-messaging
A crate which offers non-blocking publish/subscribe functionality using Tokio channels.
Publishing messages and subscribing to them is done using an `Messaging` instance,
which acts as a message broker.
In order to create a message broker, start by defining the structure of messages and their data (payload).
The types should implement `Message` and `MessageData` respectively.
```rust
enum MyMessage
{
Greeting,
Request
}
impl Message for MyMessage {}
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
struct MyPayload(&'static str);
impl MessageData for MyPayload {}
```
Next, create the message broker instance. Usually, you'll have a single, long-living instance.
```rust
lazy_static! {
static ref INSTANCE: Messaging = { Messaging::new() };
}
pub fn messaging() -> &'static Messaging { &INSTANCE }
```
Publish messages using the `dispatch()` function and subscribe to them using the `on()` function.
```rust
// Subscribe to messages
tokio::spawn(messaging().on(MyMessage::Request, |data: MyPayload| {
assert_eq!(data.0, "Here's a request!");
}));
// Publish a message
messaging().dispatch(MyMessage::Request, MyPayload("Here's a request!"));
```