Trait SubscriptionSource

Source

pub trait SubscriptionSource<B: Broker> {
    type Subscriber: Subscriber;

    // Required methods
    fn name(&self) -> &str;
    fn subscribe(
        self,
        broker: &B,
    ) -> impl Future<Output = Result<Self::Subscriber, B::Error>> + Send;
}

Expand description

A description of one subscription, resolved against a concrete broker at startup.

The runtime calls subscribe once, after Broker::connect, to obtain the live Subscriber. The associated Subscriber type lives on the source rather than the broker, so a single broker can offer several subscription kinds with different subscriber types (for example Redis pub/sub versus streams).

§Examples

use ruststream::{Broker, SubscriptionSource};

async fn open<B, S>(source: S, broker: &B) -> Result<S::Subscriber, B::Error>
where
    B: Broker,
    S: SubscriptionSource<B>,
{
    source.subscribe(broker).await
}