https://gist.github.com/asmallteapot/6fcd3c1484943e6800ae690e6ad35fef but in JavaScript

fixWords.js

const sampleInputs = [
    "OAuth Token",
    "Hello-World!",
];

String.prototype.capitalized = function() {
	const firstCharacter = this.charAt(0).toUpperCase();
	const remainder = this.substring(1);
	return firstCharacter + remainder;
};

String.prototype.camelCased = function() {
	const words = this.split(/[- ]/);
	let shouldCapitalizeNextWord = false;
	let output = "";
	for (wordIndex in words) {
		let word = words[wordIndex];
		let fixedWord = word.toLowerCase().replace(/[,.\/<>\?\!@#\$%\^&\*()\[\]\{\}]+/, '');
		if (shouldCapitalizeNextWord) {
			output += fixedWord.capitalized();
		} else {
			shouldCapitalizeNextWord = true;
			output += fixedWord;
		}
	}
	return output
};

for (idx in sampleInputs) {
	const sampleInput = sampleInputs[idx];
	console.log(sampleInput.camelCased());
}
// oauthToken
// helloWorld