SqsSubscription

SqsSubscription puts the queue steps on the mount chain, after the framework's own steps such as batch(n) and name.

The steps are those of SqsQueue: wait, visibility and create_if_missing. They chain after a framework step: a batch size, a name for a definition that fixed only the kind, or workers(n). A step at the mount site changes the descriptor the attribute built, so it wins over the attribute's value. The steps exist only on the chain of a subscription whose source is an SqsQueue, so they never reach another broker's subscription. The trait comes with the crate's prelude. In the manual form the steps follow map_source or name.

Example

Ten orders per receive, a 20 second long poll, and a queue the service creates.

Macros

examples/sqs_batches.rs

fn service(broker: SqsBroker) -> impl App<State = ()> {
    RustStream::new(AppInfo::new("orders-batches", "0.1.0")).with_broker(broker, |b| {
        // The size is the framework's word and becomes `MaxNumberOfMessages`; the long
        // poll and the queue's provisioning are this crate's, chained after it.
        b.include(
            reconcile
                .batch(nonzero!(10))
                .wait(Duration::from_secs(20))
                .create_if_missing(),
        );
    })
}

Manual

examples/manual/sqs_batches.rs

fn service(broker: SqsBroker) -> impl App<State = ()> {
    RustStream::new(AppInfo::new("orders-batches", "0.1.0")).with_broker(broker, |b| {
        // The size is the framework's word and becomes `MaxNumberOfMessages`; the long
        // poll and the queue's provisioning are this crate's, chained after it.
        b.include(
            subscriber("orders-batches", Reconcile)
                .batch(nonzero!(10))
                .build()
                .map_source(|_| SqsQueue::new("orders-batches"))
                .wait(Duration::from_secs(20))
                .create_if_missing(),
        );
    })
}