如何使用NSData从iOS发布的Golang服务器上读取JSON？

I'm trying to validate a receipt by sending it to my custom server from iOS.

I have my NSMutableURLRequest and set it up as so:

    let body: [String: AnyObject] = ["receipt": receipt, "prod_id": productID]

    let optionalJson: NSData?

    do {
        optionalJson = try NSJSONSerialization.dataWithJSONObject(body, options: [])
    } catch _ {
        optionalJson = nil
    }

    guard let json = optionalJson else { return }

    request.HTTPBody = json

Then I send it off to my server which is written in Go, but I don't know how to then read the data.

Previously I sent only the data (in raw form, not a JSON structure), and then turned into a base 64 encoded string as so before shipping it off:

data, _ := ioutil.ReadAll(request.Body)
encodedString := base64.StdEncoding.EncodeToString(data)

But now I the JSON structure that links a prod_id with is a string, as well as the receipt data, which I assume is bytes. How do I extract that into readable JSON then turn it into a base 64 encoded string as above?

I guess I'm not sure what structure the JSON would take.

That would be something like :

type Foo strut {
  Bar string `json:"bar"`
}

// extract
data, err := ioutil.ReadAll(request.Body)
if err != nil {
  return err
}
defer request.Body.Close()

v := &Foo{}
json.Unmarshal(data, v)    

The json:"bar" in Foo binds the JSON struct with the Go struct

You should create struct like below:

type MyRequest struct {
    Receipt string `json:"receipt"`
    ProdID string `json:"prod_id"`
}

then decode request body:

func handleMyRequest(rw http.ResponseWriter, req *http.Request) {
    decoder := json.NewDecoder(req.Body)
    var myReq MyRequest
    err := decoder.Decode(&myReq)
    if err != nil {
        panic()
    }
    log.Println(myReq)
}