I’ve started work on my RSS Manager again, and am now cutting code, which led me to put a _lot_ more thought into what data I was going to receive. Originally I was thinking only in terms of processing weblog RSS feeds, now I’m realising that a more general data aggregator would be a lot more useful.
And deciding on the data format to model the database tables on is proving tricky. I am starting to think that following RSS is going to be too limiting; to follow “RDF (there must be a better tutorial)”:http://www.xulplanet.com/tutorials/mozsdk/rdfstart.php too difficult as it’s extensible (someone *please* correct me if i’m wrong) unless I can create virtual tables for each feed, and map all the data to the display model.
Then I found “Atom”:http://www.intertwingly.net/wiki/pie/FrontPage. Is this the answer? Not sure, is my current reply. Here’s a few questions I haven’t found the answer to yet (anyone else find there wiki hard to find _information_ in?).
* Is Atom a generalised format for marking up any content, or specialised just for weblog content? The impression I get is that is has been designed with blogs in mind.
* Is it a subset of RDF or something separate?
* What do the developers see it being used for?
Data format is an important topic, and one which looks like it’ll hold up my development as I don’t want to continue until I’ve got it right. Below is shown the current database structure, based on that used by “Feed on Feeds”:http://minutillo.com/steve/feedonfeeds/. More fields will certainly appear; I’ve got a few lined up for the @Feed@ table already. Feed items will obviusly have to wait until the data structure is worked out.
!http://peter.mapledesign.co.uk/images/rss_manager_db_model.png!
4 comments ↓
Since you are interested in feed formats from a data modelling perspective, the following two presentations may be of help:
http://www.intertwingly.net/slides/2003/seybold/
http://intertwingly.net/slides/2003/xmlconf/
Thanks Sam, the second link I found useful to explore Atom further.
Can you explain though what the difference is between RDF and Atom? The former was shouted around a few years ago as the ‘best format’, and seems to still be very widely researched into at University; but I cannot find any good online documentation into it.
In essense, the difference between a database and a schema.
RDF is a mechanism for unifying everything into triples. The middle “column” is the predicate, and by defining new predicates, one creates a vocabulary.
RSS 1.0 is an RDF vocabulary expressed using the RDF/XML serialization. Neither RSS 2.0 nor Atom are RDF. They are simply “just XML”.
Again, thanks Sam for the explanation. I’m doing some reading into what ‘triples’ are (mostly stuff I’m finding on the “Redland”:http://www.redland.opensource.ac.uk/ site) and then hopefully be in a more informed position to decide what to use. Looks like it will be a RSS reader alone to start with; with potential to expand (should I be lucky enough to be allowed on a RDF-related course).
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