http json encoding errors

errors.go

package main

import (
	"encoding/json"
)

type ErrorType struct {
	Title  string `json:"title"`
	Detail string `json:"detail"`
	Code   int    `json:"code"`
	Status int
}

func (e ErrorType) Error() string {
  return e.Title
}

func (e ErrorType) toJSON() ([]byte, error) {
  return json.Marshal(e)
}

func Must(data []byte, err error) []byte {
  if err != nil {
    panic(err)
  }
  return data
}

func main() {
  err := ErrorType{"foo", "bar", 1000, 500}
  
  http.Error(httptest.NewRecorder(), Must(err.toJSON()), err.Status)
}