import nats, { Message } from \'node-nats-streaming\';

import { randomBytes } from \'crypto\'

console.clear();

// create client

const stan = nats.connect(\'ticketing\', randomBytes(4).toString(\'hex\'), {

url: \'http://localhost:4222\'

})

// Get Default stan options (functional chaining)

const options = stan.subscriptionOptions()

.setManualAckMode(true) // waits 30 seconds by default

.setDeliverAllAvailable() // Get all events emited in the past

.setDurableName(\'id-subscription\') // create a Durable Susbcription

// On connect

stan.on(\'connect\', () => {

console.log(\'Connected to NATS\');

// Set gracefull close event

stan.on(\'close\', () => {

console.log(\'NATS connection closed!\');

process.exit();

});

// Create subscription using channel id, and the second argument is the Group Queue!!

const subscription = stan.subscribe(

\'ticket:created\', // subscriber id

// \'queue-group:orders-service\', // queue group for balancing

options // Additional options

)

subscription.on(\'message\', (msg: Message) => {

const sequence = msg.getSequence();

const data = msg.getData();

if (typeof data === \'string\') {

const dataObj = JSON.parse(data);

console.log(dataObj, sequence);

}

// Acknowledge

msg.ack();

});

});

// Handler for console close events

process.on(\'SIGINT\', () => { stan.close() });

process.on(\'SIGTERM\', () => { stan.close() });

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