Serialize/Deserialize time.Time to/from JSON

jsonTime.go

// This code snippet demonstrates how to serialize/deserialize a struct
// who has one or more date fields to/from JSON.
//
// Though, this example implements both encoding.TextMarshaler and json.JSONMarshaler,
// either is necessary to format/parse time.Time in JSON format.
package main

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

type LastLogin struct {
	Login     string   `json:"login"`
	IP        string   `json:"ip"`
	CreatedAt jsonTime `json:"created_at"`
}

type jsonTime struct {
	t time.Time
}

func (j jsonTime) String() string {
	return j.t.String()
}

func (j jsonTime) MarshalText() ([]byte, error) {
	return []byte(j.t.Format("2006-01-02 15:04:05")), nil
}

func (t *jsonTime) UnmarshalText(data []byte) (err error) {
	(*t).t, err = time.Parse("2006-01-02 15:04:05", string(data))
	return err
}

func (j jsonTime) MarshalJSON() ([]byte, error) {
	return []byte(j.t.Format("\"2006-01-02 15:04:05\"")), nil
}

func (t *jsonTime) UnmarshalJSON(data []byte) (err error) {
	(*t).t, err = time.Parse("\"2006-01-02 15:04:05\"", string(data))
	return err
}

func main() {
	fmt.Println("Hello, playground")
	str := "{\"ip\": \"127.250.0.168\", \"login\": \"bernardo_stracke\", \"created_at\": \"2014-02-24 05:53:26\"}"
	ll := &LastLogin{}
	json.Unmarshal([]byte(str), ll)
	fmt.Printf("%v\n", *ll)
	js, _ := json.Marshal(*ll)
	fmt.Printf("%v\n", string(js))
}