``js
const qz = require("qz-tray");

qz.websocket.connect().then(() => {
return qz.printers.find();
}).then((printers) => {
console.log(printers);
let config = qz.configs.create('PDF');
return qz.print(config, [{
type: 'pixel',
format: 'html',
flavor: 'plain',
data: '

Hello JavaScript!

'
}]);
}).then(() => {
return qz.websocket.disconnect();
}).then(() => {
// process.exit(0);
}).catch((err) => {
console.error(err);
// process.exit(1);
});
``