Relating Atom Resources w/ Category & Link

["Peter Keane" <pkeane@xxxxxxxxxxxxxxx>]

In an eternal quest to find a simple way to express
relationships/hierachies among atom resources (entries), I have come
up with the following.  My criteria:

- simple to manage w/ the RDBMS backend
- straightforward to express w/ standard atom constructs
- relatively easy to manipulate w/ AtomPub

The basic idea is that a link and a category will share the same URI
for the link@rel and category@scheme. The parent has the link, the
children have the category.  The category@term is the atom id of the
parent, and the link@href expresses a search over the category scheme,
filtered by the parent id.

For example, a set of entries in a Art & Art History Collection, one
concerning the artist, and two about individual works:

<!-- artist entry -->

<entry>
   <id>tag:example.com/000123</id>
   <title>Vincent Van Gogh</title>
   <content>essay about Van Gogh...</content>
   <link rel="http://example.com/link/artist_works";
        href="http://example.com/link/artist_works?term=tag:example.com/000123";
        type="application/atom+xml"
        title="Artist Works: Vincent Van Gogh"/>
</entry>

<!-- two work entries -->

<entry>
   <id>tag:example.com/000124</id>
   <title>Harvest in Provence</title>
   <x:artist>Vincent Van Gogh</x:artist>
   <content>essay about this painting...</content>
   <category scheme="http://example.com/link/artist_works";
        term="tag:example.com/000123"/>
</entry>
<entry>
   <id>tag:example.com/000125</id>
   <title>The Sower</title>
   <x:artist>Vincent Van Gogh</x:artist>
   <content>essay about this painting...</content>
   <category scheme="http://example.com/link/artist_works";
        term="tag:example.com/000123"/>
</entry>

I can now use AtomPub to add or remove by simply PUTting the entry
with/without proper category. (There'll be some service doc & category
doc choreography to make most of this discoverable).

I am less concerned about fully functional interop, more concerned
with an extensible method to do these sorts of operations w/ standard
atom tools.

Evil hack? Any other thoughts?

--peter keane