topic controller

TopicsController

Overview

TopicsController is a utility class for managing topic-based subscriptions in real-time applications. It handles subscribing to topics, listening for specific events, and managing subscription lifecycles.

API Reference

Constructor

const topicsController = new TopicsController(client);

Parameter	Type	Description
client	Object	RTEngine client

Properties

Property	Type	Description
subscribed	Set	Stores currently subscribed topics

Methods

on(topic, event, callback)

Registers a callback for a specific event on a given topic.

topicsController.on('chat/room1', 'message', (data, payload) => {
  console.log('Message received:', data);
});

Parameter	Type	Description
topic	string	Topic to associate the event with
event	string	Name of the event to listen for
callback	Function	Function to execute when the event occurs on the topic

subscribe(topic)

Subscribes to a specific topic.

await topicsController.subscribe('chat/room1');

Parameter	Type	Description
topic	string	Topic to subscribe to
Returns	Promise	Resolves to true when subscription is complete

unsubscribe(topic)

Unsubscribes from a specific topic.

await topicsController.unsubscribe('chat/room1');

Parameter	Type	Description
topic	string	Topic to unsubscribe from
Returns	Promise	Resolves to true when unsubscription is complete

unsubscribeAll()

Unsubscribes from all currently subscribed topics.

await topicsController.unsubscribeAll();

| Returns | Promise | Resolves to true when all unsubscriptions are complete |

regenerate()

Refreshes all current subscriptions by unsubscribing and resubscribing.

await topicsController.regenerate();

| Returns | Promise | Resolves to true when regeneration is complete |

Basic Usage Example

// Initialize
const topicsController = new TopicsController(realTimeClient);

// Subscribe to a topic
await topicsController.subscribe('notifications');

// Listen for events on that topic
topicsController.on('notifications', 'new', handleNewNotification);

// Clean up when done
await topicsController.unsubscribe('notifications');
// Or unsubscribe from everything
await topicsController.unsubscribeAll();