Secure ID in a JavaScript Enviroment

I want to to generate a secure, randomised string, in JavaScript. There isn't much around about security in JavaScript, because it is usually used on the client-side – in this case, I'm using it on the server-side with Node.js.

I could create a for loop that adds a random character to a string each time around – but are there any libraries, functions, or anything else that I can install with npm, that uses SSL security-like code, encyption or the like?

Thanks! :)