I want to HMAC-SHA256 encryption in WSO2 EI but I cant able to find the way.

I have tried with below JS snippet but it gives library CryptoJS not found error

var hash = CryptoJS.HmacSHA256("message", "secret");
var hashInBase64 = CryptoJS.enc.Base64.stringify(hash);

What could be the solution to perform hmac encryption in wso2?