如何动态分配静态类型

I'm having a bit of trouble getting my head around the proper implementation of this. If I use the structs below which are embedded within each other and push them to a SOAP API, the response is decoded directly into the Response struct.

The problem I have is that everything except the ResponseBody struct would be used elsewhere and it seems wrong to repeat all of these structs in every implementation of it.

So I would like to:

• Keep my code as strongly typed as possible
• Use the generic soap structs elsewhere
• Assign / create the proper object at runtime.

Do I use a struct? Interface? Generics? Something else?

package soapv1

import (
    "encoding/xml"
)

//Response 
type Response struct {
    XMLName  xml.Name `xml:"Envelope"`
    SoapBody *SOAPBodyResponse
}

//SOAPBodyResponse
type SOAPBodyResponse struct {
    XMLName      xml.Name `xml:"Body"`
    Resp         *ResponseBody
    FaultDetails *Fault
}

//Fault 
type Fault struct {
    XMLName     xml.Name `xml:"Fault"`
    Faultcode   string   `xml:"faultcode"`
    Faultstring string   `xml:"faultstring"`
}

//ResponseBody
type ResponseBody struct {
    XMLName     xml.Name `xml:"loginResponse"`
    LoginReturn string   `xml:"loginReturn"`
}
// Some other code between here to prepare and post request

// read and parse the response body
result := new(Response)
err = xml.NewDecoder(res.Body).Decode(result)