Parse kubernetes memory units

k8s_memory.js

function parseMemory(units) {
	function multiply(amount, scale, base) {
		switch (scale.toLowerCase()) {
			case 'k': return amount * Math.pow(base, 1);
			case 'm': return amount * Math.pow(base, 2);
			case 'g': return amount * Math.pow(base, 3);
			case 't': return amount * Math.pow(base, 4);
			case 'p': return amount * Math.pow(base, 5);
			case 'e': return amount * Math.pow(base, 6);
			default: throw new ValueError("Unknown unit: " + scale);
		}
	}

	if (typeof units !== "string") {
		throw new TypeError("expected string");
	}

	units = units.trim();

	// Try to parse SI units
	var m = units.match(/^(\d+)\s*([KMGPE])i$/)
	if (m != null) {
		return multiply(parseInt(m[1]), m[2], 1024);
	}

	// Try to parse thousands
	var m = units.match(/^(\d+)\s*([KMGPE])$/)
	if (m != null) {
		return multiply(parseInt(m[1]), m[2], 1000);
	}

	throw ValueError("Unknown units: " + units);
}

console.log(parseMemory("28 Mi"))
console.log(parseMemory("28M"))
console.log(parseMemory("5Pi"))