Invalid field name in struct literal Golang - go

Question

I have this struct call Status and have inside another struct call Data
package model
import "time"
type Status struct {
Data struct {
OrderId string json:"orderId"
DisputeStatus string json:"disputeStatus"
DisputeCauseCategoryName string json:"disputeCauseCategoryName"
ReverseLogisticCost string json:"ReverseLogisticCost"
} json:"data"
StatusJ string json:"status"
}
And i have this function
func (s StatusServices) UpdateStatusItem(ctx context.Context, status model.Status) (error) {
statusDetails := model.Status{
OrderID: status.Data.OrderID,
}
}
In OrderId appear the error Invalid field name, i tried with this
statusDetails := model.Status{
Data: status.Data{
OrderID: status.Data.OrderID,
},
}
but i doesn't work, what can i do

Answer 1

The type model.Status has a field Data with a type defined as
struct {
OrderId string json:"orderId"
DisputeStatus string json:"disputeStatus"
DisputeCauseCategoryName string json:"disputeCauseCategoryName"
ReverseLogisticCost string json:"ReverseLogisticCost"
}
To initialize the variable, you can use a composite literal, more specifically a struct literal
func main() {
s := Status{
Data: struct {
OrderId string `json:"orderId"`
DisputeStatus string `json:"disputeStatus"`
DisputeCauseCategoryName string `json:"disputeCauseCategoryName"`
ReverseLogisticCost string `json:"ReverseLogisticCost"`
}{OrderId: "123456"},
}
fmt.Println(s)
}
https://play.golang.org/p/nLhLHNNf7Jb

Answer 2

I do not believe you can initialize a struct with a nested struct this way.
Best is to give the nested struct its own type. OR you can start with an empty struct (eg var m model.Status) and then (in a separate line) assign to s.Data.OrderId.
I believe you can only assign to a nested struct if you define and initialize it in one go (as is often done in go tests) which is consistent with the idea that this construct is useful only for onetime off uses.

Answer 3

Not sure it answers your question, but you may want to modify your model a little bit from :
type Status struct {
Data struct {
OrderId string json:"orderId"
DisputeStatus string json:"disputeStatus"
DisputeCauseCategoryName string json:"disputeCauseCategoryName"
ReverseLogisticCost string json:"ReverseLogisticCost"
} json:"data"
StatusJ string json:"status"
}
To:
type Status struct {
Data Data `json:"data"`
StatusJ string `json:"status"`
}
type Data struct {
OrderID string `json:"orderId"`
DisputeStatus string `json:"disputeStatus"`
DisputeCauseCategoryName string `json:"disputeCauseCategoryName"`
ReverseLogisticCost string `json:"reverseLogisticCost"`
}
Check the capital letter; in your example you had OrderId in your Data struct but status.Data.OrderID in your function.
Also your field Status does not contain an OrderID field which you were setting in your function.
As mentionned in comment, backticks were missing around your json tags.
A proper IDE would catch those.

Answer 4

Change OrderID to OrderId,declare the field's type upfront as per suggestion of mkopriva:
package main
import (
"fmt"
)
type StatusData struct {
OrderId string `json:"orderId"`
DisputeStatus string `json:"disputeStatus"`
DisputeCauseCategoryName string `json:"disputeCauseCategoryName"`
ReverseLogisticCost string `json:"ReverseLogisticCost"`
}
type Status struct {
Data StatusData
StatusJ string
}
func main() {
s := Status{Data: StatusData{OrderId: "123456"}}
fmt.Println(s)
}
Output:
{{123456 } }