Listening to topics

First, you have to create an instance of the Twitch API client, as outlined in its own documentation.

Then, you register that instance with a new PubSubClient instance:

import { PubSubClient } from 'twitch-pubsub-client';

const pubSubClient = new PubSubClient();
const userId = await pubSubClient.registerUserListener(apiClient);

It's very easy to listen to events in any channel an API client is registered for now:

import { PubSubSubscriptionMessage } from 'twitch-pubsub-client';

const listener = await pubSubClient.onSubscription(userId, (message: PubSubSubscriptionMessage) => {
	console.log(`${message.userDisplayName} just subscribed!`);
});

When you don't want to listen to these events anymore, you just remove the listener:

listener.remove();