const crypto = require('crypto'),
secretKey = 'RTk2eNs67Vpan3345pmrwYEBYsWXRXtGF3BKTFq8WMLLOLOL',
time = Math.round(new Date().getTime() / 1000).toString(),
body = {
timestamp: time,
validity: '2000'
};
const signature = crypto.createHmac('sha256',secretKey).update(JSON.stringify(body)).digest('hex')
Created from: https://npm.runkit.com/uuid