urlEncode.js

function fixedEncodeURIComponent(str) {
	return encodeURIComponent(str).replace(/[!'()*]/g, (c) => {
		return `%${c.charCodeAt(0).toString(16)}`;
	});
}

function urlEncode(params) {
	let data = '';
	Object.keys(params).forEach((key, idx, { length }) => {
		const k = fixedEncodeURIComponent(key.toString());
		const v = fixedEncodeURIComponent(params[key].toString());
		data += `${k}=${v}`;
		if (idx < length - 1) data += '&';
	});
	// in application/x-www-form-urlencoded spaces are replaced with +
	return data.replace(/%20/g, '+');
}