How to get more Feed items?

问题:

How would I get the next page or more results for a feed?

For example, when I go to Security Now feed page, there is no "next" link of any kind and the url parameter of "page=100" does nothing:

http://leoville.tv/podcasts/sn.xml

I get only 1 page of results of about 20 episodes. However my Google Reader can successfully retrieve episodes that are earlier than that.

回答1:

Indeed it is true that Google Reader caches the items and it is NOT possible to paginate on RSS2, RSS or Atom feeds (unless they have rel=next link, which none of them seem to have).

However, we can leverage the existing Google Reader infrastructure, with some work, to retrieve a list of, say 200 items!

Given the above podcast url we retrieve the latest 200 episodes by:

1. Using the ...google.ca/reader/atom/feed prefix instead of the usual view/feed as can be seen in your google reader.
2. Appending n=200 as the query parameter.

So we have:

http://www.google.ca/reader/atom/feed/http://leoville.tv/podcasts/sn.xml?hl=en&n=200

There is a very insightful reverse-engineered google-reader API project located at http://code.google.com/p/pyrfeed/wiki/GoogleReaderAPI

回答2:

Google reader caches RSS entries. You can't get any more from the actual feed if they don't allow for it.