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Installation & Basic Usage

Installation

Below is an installation example using deep-equal.

npm install runneljs @runnel/validator deep-equal

Preparation

runnel requires two dependencies to be installed.

Dependency #1: Deep Equal

The first dependency is used to compare two objects and requires the following interface:

interface DeepEqual {
  (a: object, b, object): boolean;
}

deep-equal and lodash.isequal are good libraries for this.

Dependency #2: JSON Schema Validator

The second dependency validates payloads against a JSON Schema. The interface is as follows:

interface Validator {
  (jsonSchema: object): (payload?: unknown) => boolean;
}

You can use the package @runnel/validator for this purpose.

Please read Make Your Own Validator if you need a customized validator.

Usage

  1. Initialize an event bus with createEventBus which returns registerTopic.
import { runnel } from "runneljs";
import deepEqual from "deep-equal";
import { validator } from "@runnel/validator";

const { registerTopic } = runnel("my-event-bus", deepEqual, validator);
  1. Create an event topic.
const exampleTopic = registerTopic<string>("messageTopic", {
  type: "string",
});
  1. Publish and subscribe to events using the topic.
exampleTopic.publish("Hello World");

exampleTopic.subscribe((payload: string) => alert(`Received [${payload}]`));