In this json I want to change the value of an key from int to string in golang.

Input:

{
    "id": 12345,
    "wrapper": 898984,
    "sections": {
        "main": {
            "type": 76899
        }
    },
    "order": [
        82322
    ]
}

Desired output:

{
    "id": "12345",
    "wrapper": "898984",
    "sections": {
        "main": {
            "type": "76899"
        }
    },
    "order": [
        "82322"
    ]
}

CodePudding user response：

The most straightforward way is to create structs for both jsons. Then create function that converts one to another:

package main

import (
    "encoding/json"
    "fmt"
    "strconv"
)

var input = `{ "id": 12345, "wrapper": 898984, "sections": { "main": { "type": 76899 } }, "order": [ 82322 ] }`

type DataWithInts struct {
    ID       int `json:"id"`
    Wrapper  int `json:"wrapper"`
    Sections struct {
        Main struct {
            Type int `json:"type"`
        } `json:"main"`
    } `json:"sections"`
    Order []int `json:"order"`
}

type MainStringsData struct {
    Type string `json:"type"`
}

type SectionsStringsData struct {
    Main MainStringsData `json:"main"`
}

type DataWithStrings struct {
    ID       string              `json:"id"`
    Wrapper  string              `json:"wrapper"`
    Sections SectionsStringsData `json:"sections"`
    Order    []string            `json:"order"`
}

func GetDataWithStrings(data *DataWithInts) *DataWithStrings {
    var order []string
    for _, v := range data.Order {
        order = append(order, strconv.Itoa(v))
    }
    return &DataWithStrings{
        ID:      strconv.Itoa(data.ID),
        Wrapper: strconv.Itoa(data.Wrapper),
        Sections: SectionsStringsData{
            Main: MainStringsData{
                Type: strconv.Itoa(data.Sections.Main.Type),
            },
        },
        Order: order,
    }
}

func main() {
    var dataInts DataWithInts
    err := json.Unmarshal([]byte(input), &dataInts)
    if err != nil {
        panic(err)
    }
    dataStrings := GetDataWithStrings(&dataInts)
    jsonData, err := json.Marshal(dataStrings)
    if err != nil {
        panic(err)
    }
    fmt.Println(string(jsonData))
}

more universal approach can use direct json parsing or reflect package.

P.S. To create structs, following site can be used: https://mholt.github.io/json-to-go/