MeBus

MeBus is a type safe, runtime validated, event bus. It is a wrapper around native browser event system, and it uses io-ts.

Use cases

• Micro frontends communication

  Microfrontends are, by design, disconnected from each other. They are independent applications that are composed together to form a single user interface. This means that they need a way to communicate with each other. MeBus can be used to create a type safe a communication layer between microfrontends. Microfronteds only need to share same event schema.

• Event driven architecture

  MeBus can be used to create an event driven architecture. It can be used to create a communication layer between different parts of an application.

Installation

You can install MeBus using npm:

npm i mebus

Usage

import { MeBus } from 'mebus';
import * as t from 'io-ts'

const myEventSchema = {
  event1: t.type({
    data: t.string
  }),
  event2: t.type({
    id: t.number
  }),
  ["namespace::event3"]: t.type({
    foo: t.boolean
  }),
}


const bus = new MeBus(MyEventSchema);

bus.subscribe("event1", ({ data }) => {
  console.log("event1 received", data);
});

bus.publish("event2", { id: "Hello, world!" });

API

• constructor(eventSchema: Record<string, TypeC) Creates a new instance of MeBus.

  • eventSchema: An object that defines the schema for the events. The keys are the event names and the values are the io-ts schemas for the event payloads.

• subscribe(eventName: string, handler: (payload: any) => void): void

  Subscribes to an event. The handler function will be called whenever the event is published.

  • eventName: The name of the event to subscribe to.

  • handler: The function to call when the event is published. The function will be called with the payload of the event.

• unsubscribe(eventName: string, handler: (payload: any) => void): void

  Unsubscribes from an event.

  • eventName: The name of the event to unsubscribe from.

  • handler: The function to unsubscribe.

• publish(eventName: string, payload: any): void

  Publishes an event with window.dispatchEvent

  • eventName: The name of the event to publish.

  • payload: The payload of the event.

License

MIT