"gopkg.in/yaml.v3"包用于yaml数据格式的序列化和解析。
提供了与"encoding/json"包类似的序列化反序列化方法和接口。

func Marshal(in any) (out []byte, err error)
func Unmarshal(in []byte, out any) (err error)

type Marshaler interface {
	MarshalYAML() (interface{}, error)
}
type Unmarshaler interface {
	UnmarshalYAML(value *Node) error
}

func NewEncoder(w io.Writer) *Encoder 初始化一个编码器
func (e *Encoder) SetIndent(spaces int) 设置缩进空格数
func (e *Encoder) Encode(v any) (err error) 编码写入数据
func (e *Encoder) Close() (err error) 写入剩余数据并关闭编码器

func NewDecoder(r io.Reader) *Decoder 初始化一个解码器
func (dec *Decoder) KnownFields(enable bool) 确保要解码的键在结构体字段中存在
func (dec *Decoder) Decode(v any) (err error) 解码数据

========== ========== ========== ========== ==========

type Data struct {
	Bool     bool
	Int      int
	Float    float64 `yaml:"pi"`
	String   string
	Content  string
	Array    []string
	Bytes    []byte `yaml:",flow"`
	Map      map[string]any
	Object   map[string]any `yaml:",flow"`
	Duration time.Duration
	Time     time.Time
	Struct   Struct
}
type Struct struct {
	AppID   string
	secret  string
	Float32 float32
}

func en() {
	data := &Data{
		Bool:   true,
		Int:    1,
		Float:  3.141592653,
		String: "ABC",
		Content: `xxx
yyy
zzz`,
		Array: []string{"apple", "banana"},
		Bytes: []byte{65, 66, 67},
		Map: map[string]any{
			"key": "max_int64",
			"num": math.MaxInt64,
		},
		Object: map[string]any{
			"key": "min_int32",
			"num": math.MinInt32,
		},
		Duration: 2*time.Hour + 3*time.Minute + 4*time.Second + 5*time.Millisecond,
		Time:     time.Date(2022, 1, 1, 13, 14, 15, 0, time.Local),
		Struct:   Struct{AppID: "wxa", secret: "sec", Float32: math.MaxFloat32},
	}
	b, _ := yaml.Marshal(data)
	os.WriteFile("output.yaml", b, 0666)
}

/*
bool: true
int: 1
pi: 3.141592653
string: ABC
content: |-
    xxx
    yyy
    zzz
array:
    - apple
    - banana
bytes: [65, 66, 67]
map:
    key: max_int64
    num: 9223372036854775807
object: {key: min_int32, num: -2147483648}
duration: 2h3m4.005s
time: 2022-01-01T13:14:15+08:00
struct:
    appid: wxa
    float32: 3.4028235e+38
*/

func de() {
	s := `bool: true
int: 1
pi: 3.141592653
string: ABC
content: |-
    xxx
    yyy
    zzz
array:
    - apple
    - banana
bytes: [65, 66, 67]
map:
    key: max_int64
    num: 9223372036854775807
object: {key: min_int32, num: -2147483648}
duration: 2h3m4.005s
time: 2022-1-1
struct:
    appid: wxa
    float32: 3.4028235e+38
`
	var result Data
	err := yaml.Unmarshal([]byte(s), &result)
	fmt.Println(err)
	fmt.Printf("%+v", result) //...Time:2022-01-01 00:00:00 +0000 UTC...
}