使用 AWS Pinpoint and Go 发送包含 RAW 内容的电子邮件 returns 403

Question

我正在尝试通过 AWS pinpoint 发送包含附件的电子邮件。要使用电子邮件发送附件，您必须使用 'RAW' 电子邮件内容。我能找到的关于此的唯一文档是：https://docs.aws.amazon.com/pinpoint-email/latest/APIReference/API_RawMessage.html，但它缺少很多东西（比如，需要什么 headers？）

当我使用 'simple' 内容发送电子邮件时，它工作正常：

emailInput := &pinpointemail.SendEmailInput{
    Destination: &pinpointemail.Destination{
        ToAddresses: []*string{&address},
    },
    FromEmailAddress: &sender,
    Content: &pinpointemail.EmailContent{
                Simple: &pinpointemail.Message{
                    Body: &pinpointemail.Body{
                        Html: &pinpointemail.Content{
                            Charset: &charset,
                            Data:    &emailHTML,
                        },
                        Text: &pinpointemail.Content{
                            Charset: &charset,
                            Data:    &emailText,
                        },
                    },
                    Subject: &pinpointemail.Content{
                        Charset: &charset,
                        Data:    &emailSubject,
                    },
                },
}

因为我要添加附件，所以我必须使用 'RAW' 内容类型。我编写了一个生成电子邮件内容的函数，基于：https://gist.github.com/douglasmakey/90753ecf37ac10c25873825097f46300:

func generateRawEmailContent(subject, to, from, HTMLBody string, attachments *[]EmailAttachment) []byte {
    buf := bytes.NewBuffer(nil)
    buf.WriteString(fmt.Sprintf("Subject: %s\n", subject))
    buf.WriteString(fmt.Sprintf("To: %s\n", to))
    buf.WriteString(fmt.Sprintf("From: %s\n\n", from))

    buf.WriteString("MIME-version: 1.0;\nContent-Type: text/html; charset=\"UTF-8\";\n\n")
    buf.WriteString(HTMLBody)

    writer := multipart.NewWriter(buf)
    boundary := writer.Boundary()

    buf.WriteString(fmt.Sprintf("Content-Type: multipart/mixed; boundary=%s\n", boundary))
    buf.WriteString(fmt.Sprintf("--%s\n", boundary))

    for _, attachment := range *attachments {
        buf.WriteString(fmt.Sprintf("\n\n--%s\n", boundary))
        buf.WriteString(fmt.Sprintf("Content-Type: %s\n", http.DetectContentType(attachment.Data)))
        buf.WriteString("Content-Transfer-Encoding: base64\n")
        buf.WriteString(fmt.Sprintf("Content-Disposition: attachment; filename=%s\n", attachment.FileName))

        b := make([]byte, base64.StdEncoding.EncodedLen(len(attachment.Data)))
        base64.StdEncoding.Encode(b, attachment.Data)
        buf.Write(b)
        buf.WriteString(fmt.Sprintf("\n--%s", boundary))
    }

    buf.WriteString("--")

    log.Println(string(buf.Bytes()))

    return buf.Bytes()
}

这会生成以下内容（电子邮件已更改）：

Subject: Welcome \nTo: xxxxx@gmail.com\nFrom: xxxxx@gmail.com\n\nMIME-version: 1.0;\nContent-Type: text/html; charset=\"UTF-8\";\n\n\u003ch1\u003eHello ,\u003c/h1\u003e\u003cp\u003eYou now have an account.\u003c/p\u003e\nContent-Type: multipart/mixed; boundary=8f6b2cc498b79f5a99550b930ba1ecab1fc1ee2d3425a0a69ab67b83b647\n--8f6b2cc498b79f5a99550b930ba1ecab1fc1ee2d3425a0a69ab67b83b647\n\n\n--8f6b2cc498b79f5a99550b930ba1ecab1fc1ee2d3425a0a69ab67b83b647\nContent-Type: text/plain; charset=utf-8\nContent-Transfer-Encoding: base64\nContent-Disposition: attachment; filename=test.json\newogICJ0ZXN0IjogdHJ1ZQp9\n--8f6b2cc498b79f5a99550b930ba1ecab1fc1ee2d3425a0a69ab67b83b647--

然后我按如下方式构建电子邮件：

&pinpointemail.SendEmailInput{
    Destination: &pinpointemail.Destination{
        ToAddresses: []*string{&address},
    },
    FromEmailAddress: &sender,
    Content: &pinpointemail.EmailContent{
                Raw: &pinpointemail.RawMessage{
                    Data: generateRawEmailContent(emailSubject, address, sender, emailHTML, emailAttachments),
                },
}

当通过 github.com/aws/aws-sdk-go/service/pinpoint 包裹发送此电子邮件时，我收到 403 返回，我不知道为什么。 403 意味着我试图访问的资源被禁止，但我不明白这与这里有什么关系？此外，没有关于 403 的文档，甚至是可能的响应。任何帮助将不胜感激！

我也尝试过使用库，例如 gomail-v2 库，如下所示：

m := gomail.NewMessage()
    m.SetHeader("From", from)
    m.SetHeader("To", to)
    m.SetHeader("Subject", subject)
    m.SetBody("text/plain", textBody)
    m.AddAlternative("text/html", HTMLBody)
    m.Attach("foo.txt", gomail.SetCopyFunc(func(w io.Writer) error {
        _, err := w.Write((*attachments)[0].Data)
        return err
    }))

    buf := bytes.NewBuffer(make([]byte, 0, 2048))
    _, werr := m.WriteTo(buf)
    if werr != nil {
        return nil, common.NewStackError(werr)
    }

但这仍然给我一个 403 错误。

Answer 1

我不是 Go 的人，所以这只是一种粗暴的尝试，试图绕过代码行以产生有效的 MIME 结构。

func generateRawEmailContent(subject, to, from, HTMLBody string, attachments *[]EmailAttachment) []byte {
    buf := bytes.NewBuffer(nil)
    // Creating headers by gluing together strings is precarious.
    // I'm sure there must be a better way.
    buf.WriteString(fmt.Sprintf("Subject: %s\n", subject))
    buf.WriteString(fmt.Sprintf("To: %s\n", to))
    // Remove spurious newline
    buf.WriteString(fmt.Sprintf("From: %s\n", from))

    writer := multipart.NewWriter(buf)
    boundary := writer.Boundary()

    buf.WriteString(fmt.Sprintf("MIME-Version: 1.0\n", boundary))
    buf.WriteString(fmt.Sprintf("Content-Type: multipart/mixed; boundary=%s\n", boundary))
    // End of headers
    buf.WriteString("\n")

    buf.WriteString(fmt.Sprintf("--%s\n", boundary))

    buf.WriteString("Content-Type: text/html; charset=\"UTF-8\";\n\n")
    buf.WriteString(HTMLBody)

    for _, attachment := range *attachments {
        buf.WriteString(fmt.Sprintf("\n\n--%s\n", boundary))
        buf.WriteString(fmt.Sprintf("Content-Type: %s\n", http.DetectContentType(attachment.Data)))
        buf.WriteString("Content-Transfer-Encoding: base64\n")
        buf.WriteString(fmt.Sprintf("Content-Disposition: attachment; filename=%s\n", attachment.FileName))

        b := make([]byte, base64.StdEncoding.EncodedLen(len(attachment.Data)))
        base64.StdEncoding.Encode(b, attachment.Data)
        buf.Write(b)
        // Don't add a second boundary here
        buf.WriteString("\n")
    }

    // Final terminating boundary, notice -- after
    buf.WriteString(fmt.Sprintf("\n--%s--\n", boundary))

    log.Println(string(buf.Bytes()))

    return buf.Bytes()
}

结果输出应该类似于

Subject: subject
To: recipient <victim@example.org>
From: me <sender@example.net>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary=foobar

--foobar
Content-Type: text/html; charset="UTF-8"

<h1>Tremble, victim</h1>
<p>We don't send <tt>text/plain</tt> because we
hate our users.</p>

--foobar
Content-Type: application/octet-stream
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename=skull_crossbones.jpg

YmluYXJ5ZGF0YQ==
--foobar--

Answer 2

好的，找到问题了。事实证明，这个 403 错误与我的代码无关，而是与 AWS 中的 IAM 权限有关。显然必须启用 IAM 权限才能启用 RAW 电子邮件内容。

使用 AWS Pinpoint and Go 发送包含 RAW 内容的电子邮件 returns 403

Sending an email with RAW content using AWS Pinpoint and Go returns 403

email

mime

go

amazon-web-services

aws-pinpoint