blob: d61b67c61498b480bce2447d7378643e925f3c6f [file] [log] [blame]
// +build OMIT
package main
import (
"bytes"
"encoding/json"
"fmt"
"log"
"strings"
"time"
)
const input = `{
"name":"Gopher",
"birthdate": "2009/11/10",
"shirt-size": "XS"
}`
type Person struct {
Name string
Born time.Time
Size ShirtSize
}
type ShirtSize byte
const (
NA ShirtSize = iota
XS
S
M
L
XL
)
func (ss ShirtSize) String() string {
s, ok := map[ShirtSize]string{XS: "XS", S: "S", M: "M", L: "L", XL: "XL"}[ss]
if !ok {
return "invalid ShirtSize"
}
return s
}
func (ss *ShirtSize) UnmarshalJSON(data []byte) error {
// Extract the string from data.
var s string
if err := json.Unmarshal(data, &s); err != nil { // HL
return fmt.Errorf("shirt-size should be a string, got %s", data)
}
// The rest is equivalen to ParseShirtSize.
got, ok := map[string]ShirtSize{"XS": XS, "S": S, "M": M, "L": L, "XL": XL}[s]
if !ok {
return fmt.Errorf("invalid ShirtSize %q", s)
}
*ss = got // HL
return nil
}
func (p *Person) UnmarshalJSON(data []byte) error {
var aux struct {
Name string
Born string `json:"birthdate"`
Size ShirtSize `json:"shirt-size"` // HL
}
dec := json.NewDecoder(bytes.NewReader(data))
if err := dec.Decode(&aux); err != nil {
return fmt.Errorf("decode person: %v", err)
}
p.Name = aux.Name
p.Size = aux.Size // HL
// ... rest of function omitted ...
born, err := time.Parse("2006/01/02", aux.Born)
if err != nil {
return fmt.Errorf("invalid date: %v", err)
}
p.Born = born
return nil
}
func main() {
var p Person
dec := json.NewDecoder(strings.NewReader(input))
if err := dec.Decode(&p); err != nil {
log.Fatalf("parse person: %v", err)
}
fmt.Println(p)
}