Had some time to hack on Pentropy last night and managed to get RSS 2.0 working (remarkably easy using xsd2breve), one-off pages (i.e. the "about" link) and the beginnings of an admin interface.

To give a quick example of how easy it was to create an RSS feed in Breve, here's the steps I followed:

First I needed to obtain an xsd file for RSS (this took some Googling as apparently there isn't an actual formal standard). I ended up using the one found here.

The next step is to create a test RSS feed. To this end I copied an example off some random site and edited it by hand:

rss (version="2.0") [
    channel [
        title [ 'Google Jobs' ],
        link [ 'http://www.google.com/support/jobs/' ],
        description [ 'Information about job openings at Google Inc.' ],
        item [
            title [ 'HR Analyst - Mountain View' ],
            link [ 'http://www.google.com/support/jobs/bin/topic.py?dep_id=1077&loc_id=1116 ],
            description [ '''
                We have an immediate need for an experienced
                analytical HR professional.
                The ideal candidate has a proven record of developing
                analytical frameworks to make fact-based decisions.
            ''' ]
        ]
    ]
]

I saved this template in templates/feeds/rss20.b. This gives us a bit of test data to verify our custom tags and template are working.

Next we need to create our custom tags and put them in a place where Breve can find them:

$ mkdir custom_tags
$ cd custom_tags
$ xsd2breve http://www.westinkriebel.com/Public/RSS20.xsd > rss20.py

Now we need to add our custom_tags directory to our Python path and tell Breve to actually use them:

# a Pylons controller
import sys; sys.path.append ( 'pentropy/custom_tags' )

class FeedController ( BaseController ):
    def rss20 ( self ):
        return render_response ( 'feeds/rss20?format=rss20' )

Now I can visit '/feeds/rss20' and see the result (a fantastic RSS feed).

The argument format=rss20 tells Breve to import tags from a module with that name.

Next is to put some actual data into the feed. Modify the controller to return the actual data:

def rss20 ( self ):
     c.posts = Post.select (
         order_by = [ desc ( Post.c.post_date ) ],
         limit = 50
     )
     return render_response ( 'feeds/rss20?format=rss20' )

and in our template:

rss ( version="2.0" ) [
    channel [
        title [ 'Pentropy' ],
        link [ 'http://pentropy.twisty-industries.com/' ],
        description [ 'Random Stuff' ],
        [ item [
              title [ _p.title ],
              link [ 'http://pentropy.twisty-industries.com/%s' % _p.slug ],
              description [ cdata ( _p.html_content ) ]
        ] for _p in c.posts ]
    ]
]

Now clearly, at some point I'll want to pull some of that data from the database or a config file, but for now it actually works.