A mock NATS client for Node.js

Usage no npm install needed!

<script type="module">
  import sensorfactdevMockNodeNats from 'https://cdn.skypack.dev/@sensorfactdev/mock-node-nats';



This is a small mocking library aimed at facilitating tests of our NATS-connected services.

It exposes a NATS class based on the API provided by node-nats. It maintains an in-memory "bus" shared accross the class' instances.

NB: This is very much a work in progress that fits our particular current needs. Additional development is needed to mock the node-nats API more faithfully, e.g. supporting options, completing the signatures of existing methods, etc.


npm install @sensorfactdev/mock-node-nats


const NATS = require(@sensorfactdev/mock-node-nats);
const nats = NATS.connect();

// Simple Publisher
nats.publish('subject', 'message!');

// Simple Subscriber
nats.subscribe('subject', msg => {
  console.log(`Received a message: ${msg}`);

// Unsubscribing
const sid = nats.subscribe('subject', msg => {});

// Request
const sid = nats.request('request', res => {
  console.log(`Received a message: ${res}`););

// Access the list of subs (useful for testing)
const subs = nats.subs;

// Close connection