How Do I Fetch All Old Items on an RSS Feed?

Question

I\'ve been experimenting with writing my own RSS reader. I can handle the \"parse XML\" bit. The thing I\'m getting stuck on is \"How do I fetch older posts?\"

Mos

Answer 1

All previous answers more or less relied on existing services to still have a copy of that feed or the feed engine to be able to provide older items dynamically.

There's though another, admittedly pro-active and rather theoretical way to do so: Let your feedreader use a caching proxy which semantically understands RSS and/or Atom feeds and caches them on a per-item base up to as many items as you configure.

If the feedreader doesn't poll feeds regularily, the proxy could fetch known feeds time-based on its own to not miss an item in highly volatile feeds like the one from User Friendly which has only one item and changes every day (or at least used to do so). Hence if the feedreadere.g. crashed or lost network connection while you are away for a few days, you might loose items in your feedreader's cache. Having the proxy to fetch those feeds regularily (e.g. from a data center instead from at home or on a server instead of a laptop) allows you to easily run the feedreader only then and when without loosing items which were posted after your feedreader fetched feeds the last time but rotated out again before you fetch them the next time.

I call that concept a Semantic Feed Proxy and I've implemented a proof of concept implementation called sfp. It's though not much more than a proof of concept and I haven't developed it further. (So I'd be happy about hints to projects with similar ideas or purposes. :-)