我正在尝试创建一个HTTP端点，它将处理来自网站的表单提交。
该表单包含以下字段：

• 姓名
• 电子邮件
• 联系电话
• 电子邮件正文（电子邮件正文的文本）
• 照片（最多5张）

然后，我的端点将向site@mysite.co.uk发送一封电子邮件，其中照片作为附件，电子邮件正文如下所示：
约翰（john@example.com）说：
电子邮件正文...
我是新的去，但我一直试图让这个工作了2个星期，仍然没有任何运气。
我现在的代码是：

package aj

import (
    "bytes"
    "encoding/base64"
    "fmt"
    "io/ioutil"
    "mime"
    "net/http"
    "net/mail"
    "net/textproto"
    "os"

    "github.com/aws/aws-sdk-go-v2/aws"
    "github.com/aws/aws-sdk-go-v2/service/sesv2"
    "github.com/aws/aws-sdk-go-v2/service/sesv2/types"
    "go.uber.org/zap"
)

const expectedContentType string = "multipart/form-data"
const charset string = "UTF-8"

func FormSubmissionHandler(logger *zap.Logger, emailSender EmailSender) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        logger.Info("running the form submission handler...")

        // get the destination email address
        destinationEmail := os.Getenv("DESTINATION_EMAIL")

        // get the subject line of the email
        emailSubject := os.Getenv("EMAIL_SUBJECT")

        // enforce a multipart/form-data content-type
        contentType := r.Header.Get("content-type")

        mediatype, _, err := mime.ParseMediaType(contentType)
        if err != nil {
            logger.Error("error when parsing the mime type", zap.Error(err))
            http.Error(w, err.Error(), http.StatusBadRequest)
            return
        }

        if mediatype != expectedContentType {
            logger.Error("unsupported content-type", zap.Error(err))
            http.Error(w, fmt.Sprintf("api expects %v content-type", expectedContentType), http.StatusUnsupportedMediaType)
            return
        }

        err = r.ParseMultipartForm(10 << 20)
        if err != nil {
            logger.Error("error parsing form data", zap.Error(err))
            http.Error(w, "error parsing form data", http.StatusBadRequest)
            return
        }

        name := r.MultipartForm.Value["name"]
        if len(name) == 0 {
            logger.Error("name not set", zap.Error(err))
            http.Error(w, "api expects name to be set", http.StatusBadRequest)
            return
        }

        email := r.MultipartForm.Value["email"]
        if len(email) == 0 {
            logger.Error("email not set", zap.Error(err))
            http.Error(w, "api expects email to be set", http.StatusBadRequest)
            return
        }

        phone := r.MultipartForm.Value["phone"]
        if len(phone) == 0 {
            logger.Error("phone not set", zap.Error(err))
            http.Error(w, "api expects phone to be set", http.StatusBadRequest)
            return
        }

        body := r.MultipartForm.Value["body"]
        if len(body) == 0 {
            logger.Error("body not set", zap.Error(err))
            http.Error(w, "api expects body to be set", http.StatusBadRequest)
            return
        }

        files := r.MultipartForm.File["photos"]
        if len(files) == 0 {
            logger.Error("no files were submitted", zap.Error(err))
            http.Error(w, "api expects one or more files to be submitted", http.StatusBadRequest)
            return
        }

        emailService := NewEmailService()

        sendEmailInput := sesv2.SendEmailInput{}

        destination := &types.Destination{
            ToAddresses: []string{destinationEmail},
        }

        // add the attachments to the email
        for _, file := range files {
            f, err := file.Open()
            if err != nil {
                http.Error(w, err.Error(), http.StatusInternalServerError)
                return
            }
            defer f.Close()

            // not sure what to do here to get the email with the attachements
        }

        message := &types.RawMessage{
            Data: make([]byte, 0), // This must change to be the bytes of the raw message
        }

        content := &types.EmailContent{
            Raw: message,
        }

        sendEmailInput.Content = content
        sendEmailInput.Destination = destination
        sendEmailInput.FromEmailAddress = aws.String(email[0])

        err = emailService.SendEmail(logger, r.Context(), &sendEmailInput)
        if err != nil {
            logger.Error("an error occured sending the email", zap.Error(err))
            http.Error(w, "error sending email", http.StatusBadRequest)
            return
        }

        w.WriteHeader(http.StatusOK)
    })
}

我的理解是（如果我错了，请纠正我），我必须构建一个similar to this的原始消息。