One feature of Google Reader is that it maintains a history of all items of a subscribed feed and you have access to those items when you keep scrolling down the list.
In contrast if you visit the original feed from a blog or a news site, the feed will only contain the latest 10-20 posts, but Google Reader can show you more than that.
This is a very handy feature and I was wondering if there is a kind of API available to access the RSS or ATOM Feed as displayed by Google Reader.
I came across this site that describes an unofficial API for Google Reader:
http://code.google.com/p/pyrfeed/wiki/GoogleReaderAPI
And it includes the API method I was looking for:
http://www.google.com/reader/atom/feed/url of feed?n=number of items (default 20)
This works – however the drawback is that you need to be authenticated first.
I am looking for a simple solution to access a feed with all historic items of a given feed url from Google without the need to be authenticated. The idea is to use this as an input for further processing (e.g. in Yahoo Pipes)
You can instead use http://www.google.com/reader/public/atom/feed/<escaped_feed_url> to get at this data without needing authentication.