Messaging

These features remain application-owned in 4.0.0. Upgrade them along with core and common, and review the migration guide for removed global accessors and changed contracts.

Messaging

@heronjs/ebs supports Kafka, NATS and AMQP. Declare adapters and handlers in modules, then inject or resolve their application-owned registrations. Global helpers such as usePublisher, useStreamer, useKafka, useNats and useAMQP have been removed.

Consumers normalize values, Promises and Observables before treating work as settled, retaining each transport’s acknowledgement policy. Stream publishing is ordered; failures propagate, empty sources complete normally and StreamerInput.signal cancels subscriptions. End hooks run after in-flight publishes settle. AMQP publishing waits for writable backpressure.