Using nested struct to save master-detail POST request

[Hugh Myrie]

I am able to decode the body of a POST request using json.NewDecoder(r.Body)., then save the result to a database. 

Example:

type Product struct {

ID    int  `json:"id"`   

Description  string  `json:"description"`

Price   float64 `json:"price"`

Packsize int `json:"packsize"`

Count1 int `json:"count1"`

Bin string `json:"bin"`

Qoh int `json:"qoh"`

}

items := []Product{}

err := json.NewDecoder(r.Body).Decode(&items)

    if err != nil {

        http.Error(w, err.Error(), http.StatusBadRequest)

fmt.Println("Error occurs here")

log.Printf(err.Error())

        return

    }

How can I use a nested struct to produce two slices from an incoming (master-detail) POST request, in the form:

[{receipt: 1, date: '01/01/2021', customer: 'Cash' , subtotal: 10.70,

 detail: [{receipt: 1, description: 'item1', price: 2.00, qty: 2},

              {receipt: 1, description: 'item2', price: 2.50, qty: 1},

              {receipt: 1, description: 'item3', price: 4.20, qty: 1}]

]

I am trying to avoid sending two POST requests, master followed by detail.

[Shulhan]

You can add new field with type is slice of struct inside the Product,
for example,

Details []ProductDetail `json:"detail"`