如何在 Go 的 YAML 中将字节数组呈现为字符串？

Question

我有一个以字节数组作为字段的结构。这是代码：package mainimport (    "fmt"    "gopkg.in/yaml.v3")type A struct {    PublicKey []byte `json:"PublicKey" yaml:"PublicKey"`}// Implements the Marshaler interface of the yaml pkg.func (a A) MarshalYAML() (interface{}, error) {    type alias A    node := yaml.Node{}    _ = node.Encode(alias(a))    return node, nil}func PublicKey() {    token := []byte{87, 88, 89, 90}    a := A{PublicKey: token}    fmt.Printf("A: %+v\nA.PublicKey:%s\n\n", a, a.PublicKey)    out, _ := yaml.Marshal(a)    fmt.Println(string(out))}func main() {    PublicKey()}这是输出：A: {PublicKey:[87 88 89 90]}A.PublicKey:WXYZPublicKey:    - 87    - 88    - 89    - 90是否可以让 marshal-er 将其输出为字符串而不是字节数组？例如：PublicKey: WXYZ

Answer 1

与其自定义编解码器，不如A为公钥创建自定义类型并使用 Base64 对其值进行编码/解码

type PubKey []byte

func (pk PubKey) MarshalYAML() (interface{}, error) {

    return base64.StdEncoding.EncodeToString(pk), nil

}

func (pk *PubKey) UnmarshalYAML(node *yaml.Node) error {

    value := node.Value

    ba, err := base64.StdEncoding.DecodeString(value)

    if err != nil {

        return err

    }

    *pk = ba

    return nil

}

type A struct {

    PublicKey PubKey `json:"PublicKey" yaml:"PublicKey"`

}

// No custom YAML codec

编码/解码是这样的：

func PublicKey() {

    token := []byte{87, 88, 89, 90}

    a := A{PublicKey: token}

    fmt.Printf("A: %+v\nA.PublicKey:%s\n\n", a, a.PublicKey)

    out, _ := yaml.Marshal(a)

    fmt.Println("Encoded: ", string(out))

    var b A

    err := yaml.Unmarshal(out, &b)

    if err != nil {

        println(err)

    }

    fmt.Printf("after decoding: %+v\n", b)

}

完整示例https://go.dev/play/p/2_gMi9sazIp

结果是：

A: {PublicKey:[87 88 89 90]}

A.PublicKey:WXYZ

Encoded:  PublicKey: V1hZWg==

after decoding: {PublicKey:[87 88 89 90]}

顺便说一句，base64 是编解码器如何json编组字节切片 示例与您的数据：https://go.dev/play/p/dGr0i0DnnNX

A: {PublicKey:[87 88 89 90]}

A.PublicKey:WXYZ

Encoded JSON:  {"PublicKey":"V1hZWg=="}

after decoding JSON: {PublicKey:[87 88 89 90]}