Azure Key Generation in OIC

Hi Team, We need to generate an Azure Key in OIC to connect to Azure API calls. Currently Client is using the below script in MuleSoft and we need to generate the same structure but not able to understand how these functions can be implemented as these are specific to Mule.

var sig =toBase64(fromHex(Crypto::HMACWith(secretKey as Binary, strToSign as Binary, "HmacSHA256") as Binary {class: "byte[]"}));