Pub/Sub Bus¶
Introduction¶
A Pub/Sub bus, short for Publish/Subscribe bus, is a messaging system that enables asynchronous communication between different parts of an application or system. It functions like a central communication hub where:
-
Publishers: Emit events or messages containing information about something that happened (for example, a user logged in, a product was purchased, a sensor detected a change).
-
Subscribers: Register to receive specific types of events. They're notified and receive the published messages whenever an event relevant to their interests occurs.
We explain an example of Pub/Sub bus which is a Server Side Chat Application.
function main(_, ws) { // defines main function
const ws = this.scriptForge('myScriptForge')//ScriptForge integration
const {publish, subscribe} = require('cxPubSub');//Pub/Sub Messaging:
subscribe('chat', data => ws.send(data))//Subscribing to 'chat' topic
wc.on('data', data => publish('chat', data))//Publishing to 'chat' topic
}
Thus, this code:
- Establishes a WebSocket connection through ScriptForge.
- Integrates with a Pub/Sub messaging system.
- Subscribes to the 'chat' topic to receive messages and forward them over the WebSocket.
- Listens for incoming data on the WebSocket and publishes it to the 'chat' topic, making it accessible to other parts of the application that might be interested in chat messages.