Poll: Which method do you use to navigate a MimeMessage?

[jstedfast]

MimeKit has multiple ways of walking the MIME document tree. Which method do you prefer to use to navigate the MIME tree structure in your application?

Here are some quick links to these APIs:

• MimeMessage.BodyParts
• MimeMessage.Attachments
• MimeIterator
• MimeVisitor

[jzabroski]

Here is what we do: None of the above, but I picked the first option, as it is the most relevant to us.

1. We do not navigate; we only set. To create attachments we use BodyBuilder.
2. We fully encapsulate MimeKit behind an ISmtpService (forwards) and IQueuedEmailService (stores copies for later forwarding) such that we only have about ~30 total object references to MimeKit in our whole code base, excluding MailboxAddress type (see below)
3. We have 297 references to our IQueuedEmailService, 130 of which have references to a QueuedEmailAttachmentModel
4. The primary MimeKit type we expose across our business logic layer is MailboxAddress because of MailboxAddress.Parse (134 references; it did not seem rational to implement our own, possibly incompatible, e-mail address parser).
5. Below code snippet is the only place we transform our domain model to MimeKit. Open to feedback on improving. :)

// email is an `EmailModel` with an `ICollection<QueuedEmailAttachmentModel> Attachments {get; set;}`
// message is a MimeMessage
// _fileSystem is IO Abstractions IFileSystem interface
// builder is MimeKit BodyBuilder
if (email.Attachments != null)
    foreach (var attachment in email.Attachments.Select(a => a))
    {
        if (!string.IsNullOrEmpty(attachment.StoragePath) && !string.IsNullOrEmpty(attachment.FileName))
        {
            var filePath = _fileSystem.Path.Combine(attachment.StoragePath, attachment.FileName);
            using (var stream = _fileSystem.FileStream.New(filePath, FileMode.Open, FileAccess.Read))
            {
                await builder.Attachments.AddAsync(attachment.FileName, stream, ContentType.Parse(attachment.MimeType));
            }
        }
    }

message.Body = builder.ToMessageBody();

[jstedfast]

Hey! Thanks for your participation in this poll.

This code looks good. I've got nothing to offer in the way of improvements to it.