glodev

package main

import (
	"encoding/json"
	"fmt"
)

type Data1 struct {
	SomeField string `json:"some_field"`
}

type Data2 struct {
	SomeOtherField string `json:"some_other_field"`
}

type DefaultResponse struct {
	Code int    `json:"code"`
	Msg  string `json:"msg"`
}

type Response1 struct {
	DefaultResponse
	Datas []Data1 `json:"datas"`
}

type Response2 struct {
	DefaultResponse
	Datas []Data2 `json:"datas"`
}

func main() {
	json1 := `{"code":123,"msg":"test","datas":[{"some_field":"test field data"}]}`
	json2 := `{"code":456,"msg":"test2","datas":[{"some_other_field":"other test field data"}]}`

	var res1 Response1
	var res2 Response2

	json.Unmarshal([]byte(json1), &res1)
	json.Unmarshal([]byte(json2), &res2)

	fmt.Printf("%+v\n", res1)
	fmt.Printf("%+v\n", res2)
}