Proposal: Feed History

Abstract

This is a proposal to add feed history support to our Atom feeds as per Mark Nottingham's feed-history IETF draft.

Example: Atom-formatted Paged Feed

<?xml version="1.0" encoding="utf-8"?>
   <feed xmlns="http://www.w3.org/2005/Atom">
    <title>Example Feed</title>
    <link href="http://example.org/"/>
    <link rel="self" href="http://example.org/index.atom"/>
    *<link rel="next" href="http://example.org/index.atom?page=2"/>*
    <updated>2003-12-13T18:30:02Z</updated>
    <author>
      <name>John Doe</name>
    </author>
    <id>urn:uuid:60a76c80-d399-11d9-b93C-0003939e0af6</id>
    <entry>
      <title>Atom-Powered Robots Run Amok</title>
      <link href="http://example.org/2003/12/13/atom03"/>
      <id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
      <updated>2003-12-13T18:30:02Z</updated>
      <summary>Some text.</summary>
    </entry>
   </feed>

Requirements

This proposal addresses the ability to support paging in our feeds. We currently only support the most recent N entries. If we implement feed-history, a client can intelligently make use of the added link relationships to our feed to page through them to either catch up on missed entries or get more than the offered amount of entries.

Issues

It could be a concern that we don't want people paging through all of the entries of a weblog.

Design

• Modify WeblogFeedRequest.java to support a page parameter.
• Modify FeedModel.java getWeblogEntries() method to use a WeblogEntriesListPager so we can give it a pagerURL to generate the proper first/next/previous relationships.
• Modify FeedModel.java getComments() to also use a pager.
• Modify CommentsPager.java to take in a pagerURL.
• Add #showFeedHistory macro to feeds.vm.
• Update *-atom.vm velocity templates to call #showFeedHistory.

Comments

Comments are welcome!