如何在GoLang中使用GOB编码序列化嵌套结构？

Question

I have a couple of example nested structs and need to serialize them. I am using the encoding/gob library, which should convert the struct data to bytes and the encoding/base64 library to convert the bytes to a readable base64 format. However, when I run my example code I get a serialization error error. I don't understand why this happens and how to fix the problem.

I followed this example: Golang serialize and deserialize back

Here is the code:

package main

import (
    "bytes"
    "encoding/base64"
    "encoding/gob"
    "errors"
    "fmt"
)

type Hello struct {
    greeting string
}

type Bye struct {
    helloSaid Hello
    byesaid Hello
}


func (b1 Bye) Serialize() (string, error) {
    b := bytes.Buffer{}
    e := gob.NewEncoder(&b)
    err := e.Encode(b1)
    if err != nil {
        return string(b.Bytes()[:]), errors.New("serialization failed")
    }
    return base64.StdEncoding.EncodeToString(b.Bytes()), nil
}

func DeserializeBye(str string) (Bye, error) {
    m := Bye{}
    by, err := base64.StdEncoding.DecodeString(str)
    if err != nil {
        return m, errors.New("deserialization failed")
    }
    b := bytes.Buffer{}
    b.Write(by)
    d := gob.NewDecoder(&b)
    err = d.Decode(&m)
    if err != nil {
        return m, errors.New("deserialization failed")
    }
    return m, nil
}

func main() {
    h := Hello{greeting: "hello"}
    b := Bye{helloSaid: h, byesaid: h}
    serialized, err := b.Serialize()
    if err != nil {
        fmt.Println(err)
    }
    fmt.Println(serialized)
}

Answer 1

Please, make the fields of the Hello and Bye structures public. Please see the documentation for the gob package:

Structs encode and decode only exported fields.