My proposal is to create a new standards-track RFC that updates RFC 4287.
The RFC would say only this (plus the standard RFC boilerplate text):
Abstract
This document updates RFC 4287 to allow the
atom:content's type attribute to have a
composite MIME type.
Table of Contents
1. All MIME types are allowed in atom:content .1
2. References .................................1
2.1 Normative References ...................1
Appendix A. Contributors ......................1
1. All MIME types are allowed in atom:content
The restriction on atom:content's type
attribute "but MUST NOT be a composite type"
from section 4.1.3 in RFC 4287 is removed.
There are now no restrictions on the type of
content allowed in atom:content.
The rules for processing atom:content remain
exactly as specified in Section 4.1.3.3
of [RFC4287]. In particular, when the
atom:content element contains content with
a composite MIME type, that content must be
encoded in Base64 as specified in step #6 of
that section. .
9. References
[RFC4287] Nottingham, M. and R. Sayre,
"The Atom Syndication Format",
RFC 4287, December 2005.
Appendix A. Contributors
The content and concepts within are a
product of the Atom community and the
AtomPub Working Group.
Background:
Recently, I have been working on an application for using AtomPub to archive
data--the client application watches for changed files on the local computer
and on the remote AtomPub server and ensures both of them stay in sync. It
is something like Microsoft's SyncToy.
I want to extend this to email, and I want to archive the email messages
unmodified in their message/rfc822 format. However, currently the Atom
specification forbids message/* and multipart/* in atom:content:
On the atom:content element, the value of the
"type" attribute MAY be one of "text", "html", or "xhtml".
Failing that, it MUST conform to the syntax of a MIME
media type, but MUST NOT be a composite type (see
Section 4.2.6 of [MIMEREG]).
- http://tools.ietf.org/html/rfc4287#section-4.1.3
Multipart and message are composite types[.]
- http://tools.ietf.org/html/rfc4288#section-4.2.6
Effectively, this means that if I want to archive email messages, I must
either violate RFC 4287 or I must use a non-standard MIME type for them.
I had a very similar problem archiving files that were saved using Internet
Explorer's MHT files (File > Save As > Web Archive, single file), which are
multipart/related.
Your feedback is much appreciated.
Regards,
Brian
