c# - 使用 mimekit/mailkit 库获取电子邮件的传递状态

Question

我正在使用@jstedfast Mimekit/Mailkit 库，用于从我的应用程序发送大量电子邮件。我想知道如何获取每封电子邮件的发送状态。这是我第一次尝试得到这个，在一些 RnD 之后，我知道我们必须在某个地方设置或传递 report-type=delivery-status ，但我不知道从我读到这个的文档中该在哪里做. 我也尝试覆盖 DeliveryStatusNotification，但一无所获。可能是我在错误的方向上获取通知/状态。

 protected override DeliveryStatusNotification? GetDeliveryStatusNotifications(MimeMessage message, MailboxAddress mailbox)
    {}

我了解到 @jstedfast 在这里很活跃。为此我需要你的帮助。我没有得到任何指示来做到这一点。 提前致谢。

Answer 1

您需要做的第一件事是像文档中的示例那样子类化 SmtpClient:

http://www.mimekit.net/docs/html/M_MailKit_Net_Smtp_SmtpClient_GetDeliveryStatusNotifications.htm

public class DSNSmtpClient : SmtpClient
{
    public DSNSmtpClient ()
    {
    }

    /// <summary>
    /// Get the envelope identifier to be used with delivery status notifications.
    /// </summary>
    /// <remarks>
    /// <para>The envelope identifier, if non-empty, is useful in determining which message
    /// a delivery status notification was issued for.</para>
    /// <para>The envelope identifier should be unique and may be up to 100 characters in
    /// length, but must consist only of printable ASCII characters and no white space.</para>
    /// <para>For more information, see rfc3461, section 4.4.</para>
    /// </remarks>
    /// <returns>The envelope identifier.</returns>
    /// <param name="message">The message.</param>
    protected override string GetEnvelopeId (MimeMessage message)
    {
        // Since you will want to be able to map whatever identifier you return here to the
        // message, the obvious identifier to use is probably the Message-Id value.
        return message.MessageId;
    }

    /// <summary>
    /// Get the types of delivery status notification desired for the specified recipient mailbox.
    /// </summary>
    /// <remarks>
    /// Gets the types of delivery status notification desired for the specified recipient mailbox.
    /// </remarks>
    /// <returns>The desired delivery status notification type.</returns>
    /// <param name="message">The message being sent.</param>
    /// <param name="mailbox">The mailbox.</param>
    protected override DeliveryStatusNotification? GetDeliveryStatusNotifications (MimeMessage message, MailboxAddress mailbox)
    {
        // In this example, we only want to be notified of failures to deliver to a mailbox.
        // If you also want to be notified of delays or successful deliveries, simply bitwise-or
        // whatever combination of flags you want to be notified about.
        return DeliveryStatusNotification.Failure;
    }
}

这将告诉 SMTP 服务器向您发送有关您发送的每封邮件的传递状态的电子邮件。

这些消息的顶级 MIME 类型为 multipart/report，report-type 值为 delivery-status。

换句话说，Content-Type header 将如下所示:

Content-Type: multipart/report; report-type=delivery-status; boundary=ajkfhkzfhkjhkjadskhz

使用MimeMessage.Load() 解析消息后，您可以检查Body 是否为具有预期 的MultipartReport >ReportType 属性值。

从那里，您可以找到类型为 MessageDeliveryStatus 的子部分(我认为通常是第二部分)。

从那里，您需要检查 StatusGroups 属性(请参阅 http://www.mimekit.net/docs/html/P_MimeKit_MessageDeliveryStatus_StatusGroups.htm)- 集合中的每个 HeaderList 都将包含不同收件人的信息。

您需要阅读 StatusGroups 文档中列出的 RFC，以确定您需要查找哪些可能的 header 和值。