Golang JSON

go-json.go

package main

import (
	"encoding/json"
	"fmt"
	"log"

	"github.com/tidwall/gjson"
)

type JsonMap map[string]string

type JsonStruct struct {
	Name     string `json:"name"`
	Location string `json:"location"`
	Address  string `json:"address"`
}

func (jsonStruct *JsonStruct) updateName(name string) {
	jsonStruct.Name = name
}

func merge(a, b interface{}) (interface{}, error) {

	ja, err := json.Marshal(b)
	if err != nil {
		return nil, err
	}
	err = json.Unmarshal(ja, &b)
	if err != nil {
		return nil, err
	}

	return b, nil
}

func main() {
	jsonStr := `{"name": "sai", "location": "bhainsa"}`
	jsonStrNested := `{"name": "sai", "location": "bhainsa", "nested": { "one": "1", "two": 2 }}`

	jsonMap := make(JsonMap)

	// convert this into map using default json
	if err := json.Unmarshal([]byte(jsonStr), &jsonMap); err != nil {
		log.Fatal(err.Error())
	}
	fmt.Println("name is", jsonMap["name"])

	// convert json string into struct
	jsonStruct := &JsonStruct{}
	if err := json.Unmarshal([]byte(jsonStr), jsonStruct); err != nil {
		log.Fatal(err.Error())
	}

	fmt.Println("name is", jsonStruct.Name)

	jsonStruct.updateName("Sai Umesh")

	fmt.Println("name is", jsonStruct.Name)

	result := gjson.Get(jsonStr, "name")

	fmt.Println("result", result.String())

	// nested json
	resultNested := gjson.Get(jsonStrNested, "nested.one")

	fmt.Println("nested ", resultNested.String())

	// iterate through json
	gjson.Parse(jsonStrNested).ForEach(func(key, value gjson.Result) bool {
		fmt.Println("key, value", key.String(), value.String())
		return true
	})

	// merge two structs
	one := JsonStruct{
		Name:     "sai",
		Location: "Hyderabad",
	}

	two := JsonStruct{
		Name:     "sai",
		Location: "Bangalore",
		Address:  "sasasasas",
	}

	combine, err := merge(&one, &two)
	if err != nil {
		log.Fatal(err.Error())
	}
	fmt.Println(combine)

}