Go dynamodbattribute.MarshallMap返回空映射

我试图编写一个非常简单的Go函数，将一个条目插入DynamoDB表

我正在遵循AWS文档站点上提供的教程，但出于某种原因，dynamodbattribute.marshallMap函数返回一个空映射

代码编译并运行，但在尝试插入记录时中断，因为它在映射中找不到所需的键。一个小小的println操作显示映射是空的，即使创建它的结构不是空的

感谢您的帮助

package main

import (
    "context"
    "fmt"

    "github.com/aws/aws-sdk-go/aws"

    "github.com/aws/aws-lambda-go/lambda"
    "github.com/aws/aws-sdk-go/aws/session"
    "github.com/aws/aws-sdk-go/service/dynamodb"
    "github.com/aws/aws-sdk-go/service/dynamodb/dynamodbattribute"
)

// Item Struct for Fruit Item
type Item struct {
    fruitID   int
    fruitName string
}

/*HandleRequest handles the lambda request.*/
func HandleRequest(ctx context.Context) (string, error) {
    // Initialize a session that the SDK will use to load
    // credentials from the shared credentials file ~/.aws/credentials
    // and region from the shared configuration file ~/.aws/config.
    sess := session.Must(session.NewSessionWithOptions(session.Options{
        SharedConfigState: session.SharedConfigEnable,
    }))

    // Create DynamoDB client
    svc := dynamodb.New(sess)

    item := Item{
        fruitID:   2,
        fruitName: "Orange",
    }

    fmt.Println(item)

    av, err := dynamodbattribute.MarshalMap(item)
    if err != nil {
        fmt.Println("Got error marshalling new fruit item: ")
        fmt.Println(err.Error())
        return "", err
    }

    fmt.Println("av: ", av)
    fmt.Println("ln: ", len(av))
    fmt.Println("KEY VALUE PAIRS::")
    for key, value := range av {
        fmt.Println("Key:", key, "Value:", value)
    }

    tableName := "fruits"

    input := &dynamodb.PutItemInput{
        Item:      av,
        TableName: aws.String(tableName),
    }

    _, err = svc.PutItem(input)
    if err != nil {
        fmt.Println("Got error inserting new fruit item: ")
        fmt.Println(err.Error())
        return "", err
    }

    return "SUCCESS!", nil
}

func main() {
    lambda.Start(HandleRequest)
}

Lambda的日志输出

---

struct中以大写字母开头的字段只能导出，并且可以在此包外部使用

你能试试这个结构，看看它是否有效吗

type Item struct {
    FruitID   int
    FruitName string
}

---

这应该是批准的答案，字段需要导出，所以从国会发信开始。

type Item struct {
    FruitID   int
    FruitName string
}