Anyway, for the occupyweb.org photos page, I have to use Atom, because Flickr has features in their Atom feeds that they don't provide in their RSS feeds. Such is life in the lands of Really Simple. Sometimes it's Not So Simple. But we party on, with our boots on the ground, for a greater cause. Photos!
This time I wanted to get the category elements from the feed. So I added a bit of code to a core routine in Frontier, xml.rss.getFeedItems. It takes the URL of a feed, and returns a table structure with all the information it contains. It flattens out the differences between Atom and RSS. The upper-level code just has to deal with RSS.
Google probably has a similar routine in their codebase, but it works opposite, converting RSS to Atom. It's why they can't deal with Twitter feeds properly. Atom requires items to have titles. RSS does not. Twitter items have no titles. Google screws up all RSS feeds that have no titles. They made the wrong choice. Imho.
Update: It works! The tags are now displayed on the photos page.
BTW, that's an interesting picture, isn't it. It'll scroll off very quickly so I wanted to preserve a link to it. And the real point of this work is to gain visibility for the pictures people are taking. Some very talented photographers at work here, and the subject matter is historic. It's been a couple of generations since so many people in the US have taken to the streets.