Raw JSON URL string from json marshal of a struct

ex.go

package main

import (
	`bytes`
	`fmt`
	`net/url`
	`encoding/json`
)

type Ex struct {
	Url url.URL
}
func (ex Ex) MarshalJSON() ([]byte, error) {
	tmp := struct{
		Url string `json:"url,"`
	}{
		ex.Url.String(),
	}
	b := bytes.NewBuffer([]byte(``))
	e := json.NewEncoder(b)
	e.SetEscapeHTML(false)
	err := e.Encode(tmp)
	return b.Bytes(), err
}

func main() {
	u := "http://googl.ntt/chair?hi=bye&this=that"
	urx, _ := url.Parse(u)
	e := Ex{*urx}
	b := bytes.NewBuffer([]byte(``))
	enc := json.NewEncoder(b)
	enc.SetEscapeHTML(false)
	enc.Encode(e)
	
	// {"url":"http://googl.ntt/chair?hi=bye&this=that"}
	fmt.Println(b.String())
}