Subject: Schema for the combination of Atom and its extensions

From: "MURATA Makoto (FAMILY Given)" <[email-masked]>
Date: Mon, 03 Sep 2007 02:15:05 +0900

I find that no schemas examine constraints specified 
in RFC 4287 (The Atom Syndication Format), 
RFC 4685 (Atom Threading Extensions), "Feed Paging and Archiving", 
and Open Search, all together.

I gave a lecture of schema customization at Tsukuba University and 
asked the students to try.  On the basis of their result, I created a 
schema for the combination of the above specifications.  Furthermore,
other extensions can be easily added to this schema.  

The schemas are available at:

	http://www.asahi-net.or.jp/~eb2m-mrt/atom/schemaForAtomExtensions.zip

The schema "atomRev.rnc" is a rewrite of the schema in RFC 4287. It is
created by Mr. Fujisaki at Tsukuba University, and is slightly modified
by me.

-- 
MURATA Makoto (FAMILY Given) <[email-masked]>

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From: Tim Bray <[email-masked]>
Date: Sun, 02 Sep 2007 13:48:28 -0700

> other extensions can be easily added to this schema.

Wow!  Thank you!  -Tim

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From: "MURATA Makoto (FAMILY Given)" <[email-masked]>
Date: Tue, 11 Sep 2007 12:19:30 +0900

The first version of the schema is written solely in RELAX NG.  I 
have created the second version using NVDL and RELAX NG.  Simply put, 
NVDL decomposes atom feeds in to pieces so that tiny schemas can be used
for the validation of the pieces.

I believe that the NVDL + RELAX NG version is easier to undestand and
maintain.

Both versions are available at

Cheers,

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From: James M Snell <[email-masked]>
Date: Mon, 10 Sep 2007 23:00:24 -0700

This is excellent work. Many thanks.

- James

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From: "MURATA Makoto (FAMILY Given)" <[email-masked]>
Date: Sun, 23 Sep 2007 17:43:31 +0900

Tim and James,

Thanks for encouraging comments.  

Folks,

Does somebody have a list of know extensions to atom?  If such a 
list is available, I am happy to improve the schema.  I am inclined 
to maintain the NVDL+RNG version only, since that version is much 
easier to maintain.

I tested the NVDL script using oXygen.  Its NVDL engine is publicly 
available at:  

http://www.oxygenxml.com/onvdl.html

Cheers,

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From: James M Snell <[email-masked]>
Date: Thu, 27 Sep 2007 09:59:21 -0700

There are several listed on the Atom wiki

  http://www.intertwingly.net/wiki/pie/FrontPage

Look at RFC's 4685, 4946 and 5005

There are a few other experimental, in-progress I-D's but they're not
really in active use as far as I know.

Non-standard extensions include OpenSearch, Microsoft's Simple Sharing
Extensions and GData's family of extensions.

Also, any of the RSS extensions are typically fine for use with Atom:

  http://rss-extensions.org/wiki/Main_Page

I haven't seen very many of those actually being used with Atom feeds,
however.  Those that I have seen used with Atom include GeoRSS, Dublin
Core, Yahoo Media, and Creative Commons (which should be replaced by RFC
4946).

- James