node.js HMAC SHA512 signing

sign.js

var crypto = require("crypto");

function encrypt(key, str) {
    var hmac = crypto.createHmac("sha512", key);
    var signed = hmac.update(new Buffer(str, 'utf-8')).digest("base64");
    return signed
}

Example code

console.log(encrypt("test", "hello world"));
console.log(encrypt("test", "goodbye world"));