Go JSON manipulation spike

json-test.go

package main

import (
  "log"
	"encoding/json"
)

type Hoge struct {
	Name string `json:"name"`
	Body map[string]interface{} `json:"body"`
}

type Foo struct {
	Name string `json:"name"`
	Body []interface{} `json:"body"`
}

// Simple JSON wrapping test
// I think Go is quite good at manipulating JSON at this point.
// When it need to change some fields, you might wanna use
// https://github.com/bitly/go-simplejson
func main() {
	// JSON wrapping test
	var h Hoge
	b := []byte(`{"id":"0fd34da25b13b","message":"Hello","date":"2012-12-01"}`)
	if err := json.Unmarshal(b, &h.Body); err != nil {
		panic(err.Error())
	}

	h.Name = "Tomoya"
	log.Println(h)

	if hogeJson, err := json.Marshal(&h); err != nil {
		panic(err.Error())
	} else {
		log.Println(string(hogeJson))
	}

	// JSON(Array) wrapping test
	var f Foo
	b2 := []byte(`["foo","bar","hoge", {"smagch": "tomoya"}]`)

	if err := json.Unmarshal(b2, &f.Body); err != nil {
	  panic(err.Error())
	}

	f.Name = "Smagch"
	log.Println(f)

	if fooJson, err := json.Marshal(&f); err != nil {
		panic(err.Error())
	} else {
		log.Println(string(fooJson))
	}
}

Probably, it's better to use RawMessage.