Messages

A publish policy with a fixed ordering key writes it into the googlepubsub binding of the message the mount site sends.

The message binding of googlepubsub describes what a message carries beyond its payload and attributes. This crate fills orderingKey where the mount site's policy fixed one. A key named per message, by the ordering_key step or the partition-key header, is named at a call site, which the document does not see. A message whose mount site fixed no key carries no binding.

Example

Every receipt goes out under the key receipts.

Macros

examples/pubsub_asyncapi.rs

fn service(broker: PubSubBroker) -> impl App<State = ()> {
    RustStream::new(AppInfo::new("orders", "1.0.0")).with_broker_labeled("pubsub", broker, |b| {
        // Every receipt goes out under one key, so the document states it.
        b.include(receipt)
            .out_reply(Publish::default().ordering_key("receipts"));
    })
}

Manual

examples/manual/pubsub_asyncapi.rs

fn service(broker: PubSubBroker) -> impl App<State = ()> {
    RustStream::new(AppInfo::new("orders", "1.0.0")).with_broker_labeled("pubsub", broker, |b| {
        // Every receipt goes out under one key, so the document states it.
        b.include(subscriber(orders(), ReceiptFor).reply().build())
            .out_reply(Publish::default().ordering_key("receipts"));
    })
}

The message Receipt in the document:

{
  "googlepubsub": {
    "orderingKey": "receipts",
    "bindingVersion": "0.2.0"
  }
}