Rocket.Chat.ReactNative/app/lib/methods/subscriptions/rooms.js

import database from '../../realm';
import { merge } from '../helpers/mergeSubscriptionsRooms';

export default async function subscribeRooms(id) {
	const subscriptions = Promise.all([
		this.ddp.subscribe('stream-notify-user', `${ id }/subscriptions-changed`, false),
		this.ddp.subscribe('stream-notify-user', `${ id }/rooms-changed`, false),
		this.ddp.subscribe('stream-notify-user', `${ id }/message`, false)
	]);

	let timer = null;
	const loop = (time = new Date()) => {
		if (timer) {
			return;
		}
		timer = setTimeout(async() => {
			try {
				await this.getRooms(time);
				timer = false;
				loop();
			} catch (e) {
				loop(time);
			}
		}, 5000);
	};

	if (this.ddp) {
		this.ddp.on('logged', () => {
			clearTimeout(timer);
			timer = false;
		});

		this.ddp.on('logout', () => {
			clearTimeout(timer);
			timer = true;
		});

		this.ddp.on('disconnected', () => {
			if (this._login) {
				loop();
			}
		});

		this.ddp.on('stream-notify-user', (ddpMessage) => {
			const [type, data] = ddpMessage.fields.args;
			const [, ev] = ddpMessage.fields.eventName.split('/');
			if (/subscriptions/.test(ev)) {
				const tpm = merge(data);
				return database.write(() => {
					database.create('subscriptions', tpm, true);
				});
			}
			if (/rooms/.test(ev) && type === 'updated') {
				const [sub] = database.objects('subscriptions').filtered('rid == $0', data._id);
				database.write(() => {
					merge(sub, data);
				});
			}
		});
	}

	await subscriptions;
	// console.log(this.ddp.subscriptions);
}