eventBus

Creates messaging client reader for LOCAL transport layer (Event Bus)

Importing

import { eventBus } from '@marblejs/messaging';

Type declaration

eventBus :: EventBusConfig
  -> Reader<Context, Promise<TransportLayerConnection>>

Parameters

parameter	definition
config	EventBusConfig

EventBusConfig

parameter	definition
listener	<optional> MessagingListener

Because of asynchronous nature of messaging client, all related readers have to be bound to server creators via eager binding 👉 #bindEagerlyTo

To learn more about eventBus usage please visit:

CQRS

Example

The event bus can be attached to server creator, like basic HTTP or any other microservice.

@marblejs/messaging module exposes already existing messaging client for eventBus transport layer:

import { eventBus } from '@marblejs/messaging';

Additionally it exports tokens for both EventBus and EventBusClient instances.

import { EventBusToken, EventBusClientToken } from '@marblejs/messaging';

import { httpListener, createServer, bindEagerlyTo } from '@marblejs/core';
import { messagingListener, EventBusToken, EventBusClientToken, eventBusClient, eventBus } from '@marblejs/messaging';
​
const eventBusListener = messagingListener(...);
const listener = httpListener(...);
​
export const server = createServer({
  listener,
  dependencies: [
    bindEagerlyTo(EventBusClientToken)(eventBusClient),
    bindEagerlyTo(EventBusToken)(eventBus({ listener: eventBusListener })),
  ],
});
​
const main: IO<void> = async () =>
  await (await server)();
​
main();