Node.js/Javascript function to extract HTTP Basic auth from Authorization header string

getBasicAuthArray.js

const getBasicAuthArray = data => {
	data = data.split(' ');
	if (data.length !== 2 || !data[0].length || !data[1].length || data[0].toLowerCase() !== 'basic') return [null, null];
	let basicAuthData = Buffer.from(data[1], 'base64').toString('utf8').split(':');
	return [basicAuthData.shift(), basicAuthData.join(':')];
};