knativebus

Publish and Send events to KNative via wrapping them in CloudEvents and sending via HTTP Post to the appropriate broker or channel from the config.

Usage

Create Brokers and Channels via KNative Eventing CRDs in Kubernetes:

Broker

This is configured to use an InMemory Broker. You'll want to use Kafka for production - see the KNative Docs for details.

CQRS/ES

Create a broker to send commands to for your aggregate:

apiVersion: eventing.knative.dev/v1
kind: Broker
metadata:
  name: example-commands

And a broker to publish domain events about your aggregate:

apiVersion: messaging.knative.dev/v1
kind: Broker
metadata:
  name: example-events

Node.js

Then in Node.js, you can use knativebus to publish events and send commands to these brokers by providing a configuration object with the URLs they generate by aggregate name.

import { knativebus } from 'knativebus'

const bus = knativebus({
  aggregates: {
    example: {
      commands: 'http://broker-ingress.knative-eventing.svc.cluster.local/default/example-commands',
      events: 'http://broker-ingress.knative-eventing.svc.cluster.local/default/example-events'
    }
  },
  source: 'tests',
  retry: true,
  timeout: 30 * 1000
})

const run = async () => {
  // send command to example commands broker
  await bus.send('example.initialize', { id: 1, name: 'Example 1' })

  // or publish events (past tense) to a model's events broker
  await bus.publish('example.initialized', { id: 1, name: 'Example 1' })
}

run()

register-server-handlers

This library works well in conjuction with register-server-handlers for building event driven CQRS/ES microservice systems with KNative.