xdmp.hmacSha512( secretkey as Item, message as Item, [encoding as String] ) as String
Calculates the Hash-based Message Authentication Code (HMAC) using the SHA512 hash function of the given secret key and message arguments.
xdmp.hmacSha512("foo", "bar"); => "114682914c5d017dfe59fdc804118b56a3a652a0b8870759cf9e792ed7426b08197076\ bf7d01640b1b0684df79e4b67e37485669e8ce98dbab60445f0db94fce"
xdmp.hmacSha512("foo", "bar", "base64"); => "EUaCkUxdAX3+Wf3IBBGLVqOmUqC4hwdZz555LtdCawgZcHa/fQFkCxsGhN955LZ\ +N0hWaejOmNurYERfDblPzg=="