Re: [syndication] Thoughts, questions, and issues.

[Jonathan Eisenzopf <eisen@pobox.com>]

Ian Graham wrote:
> 
> I've read the RSS 1.0 spec.  As an RDF-aware extrapolation of RSS 0.9x
> this is quite nice. However, I am looking for something a bit different:
> namely, a syndication framework that can contain RSS-style data, but that
> could also contain other sorts of data.  In particular I would like to be
> able to distribute event descriptions (conferences, concerts, etc.), the
> full text of some articles, and so on.
> 
> I've been mulling this over for a few weeks, and have some rough thoughts
> on this model and its relationship to RSS.  To my mind, this would call
> for a modular language that can describe the following classes of
> information:
> 
>   * location data  - where the 'resource' can be accessed from
>   * metadata describing basic properties of a resource (data type,
>     last modified date, who is the author/owner of the 'resource', etc.)
>   * metadata describing syndication rules for the resource
>     data (when it should be displayed, how it can be redistributed)
>   * descriptive metadata describing the content of a
>     resource (the language it's in, keywords and category labels,
>     etc.)
>   * the resource itself.
> 
> Most of this information is defined, in a limited way, in the various RSS
> elements or attributes. However, I suspect that by abstracting these away
> from being tied to the RSS 'channel' model, and by constructing a suitable
> XML framework for generic syndication data, we can make a more extensible
> specification that can encompass RSS 0.9x-style data in addition to other
> forms, and that can also allow for extensibility in the other metadata
> regimes I mentioned above.
> 
> My model for doing this is still very rough, and I am already happily
> stealing clever ideas from the new RSS 1.0 draft and adding them in.  The
> current document is very rough, and a bit embarassingly so. However, if
> anyone else is interested in pursuing this line of thought, I'd be happy
> to pass it on.
> 
A couple things. One of the reasons we did the RSS 1.0 proposal
is because of extensibility. To that end, there is a draft of an
extension module for syndication at
http://purl.org/rss/1.0/modules/. It is limited and probably
needs to be fleshed out more. Feedback would be really helpful.

As an example of how easy it is to extend via namespaces, I've
included an example that incorporates the list of items you
wanted. Note that I borrowed the syndication example and extended
it even further via the metasyn namespace. Users can do these
type of extensions without having to worry about screwing up the
base RSS. Of course, the RSS might get passed through several
aggrigators who add their own extensions. As it gets passed, if
the next guy knows about the extension, that extra info might
come in handy; if not, no problem since it won't conflict.

           <?xml version="1.0"?> 

             <rdf:RDF 
              
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"; 
              
xmlns:sy="http://purl.org/rss/1.0/modules/syndication/";
	       xmlns:metasyn="http://purl.org/rss/1.0/modules/metasyn/";
               xmlns="http://purl.org/rss/1.0/";
             > 

               <channel
rdf:about="http://meerkat.oreillynet.com/?_fl=rss1.0";>
                 <title>Meerkat</title>
                 <link>http://meerkat.oreillynet.com</link>
                 <description>Meerkat: An Open Wire
Service</description>
                 <sy:updatePeriod>hourly</sy:updatePeriod>
                 <sy:updateFrequency>2</sy:updateFrequency>
                
<sy:updateBase>2000-01-01T12:00+00:00</sy:updateBase>
               </channel>

               <item
rdf:about="http://c.moreover.com/click/here.pl?r123";
position="1">
                 <metasyn:location>NY</metasyn:location>
                
<metasyn:lastModified>2000-01-01T12:00+00:00</metasyn:lastModified>
                 <metasyn:author>Ian Graham</metasyn:author>
                 <metasyn:language>us-en</metasyn:language>
                
<metasyn:keywords>fishing,bass,bait</metasyn:keywords>
                
<metasyn:category>Fishing/Bass/Bait</metasyn:category>
                 <inchannel
rdf:resource="http://meerkat.oreillynet.com/?_fl=rss1.0"; />
                 <title>XML: A Disruptive Technology</title> 
                
<link>http://c.moreover.com/click/here.pl?r123</link>
                 <description>
                   XML is placing increasingly heavy loads on the
existing technical
                   infrastructure of the Internet.
                 </description>
               </item> 

             </rdf:RDF>

-- 
Jonathan Eisenzopf    |  http://motherofperl.com    
eisen@pobox.com       |  http://perlxml.com
Perl Hacker           |  http://dc.pm.org