Blogging Roller

I've got to carve out some time ASAP to take a close look at this. The code is in Abdera SVN and there's <a href= "http://cwiki.apache.org/confluence/download/attachments/69763/abderaserverguide.pdf"> 20-minute implementation guide (PDF) too:

James Snell: Dan Diephouse and I have been spending the last week refactoring the Abdera server framework with the goal of making is less complicated, easier, and generally better.

For Java developers starting out with RSS and Atom, here are some notes to help you figure out the differences between the Java.net ROME and Apache Abdera (incubating) projects.

ROME is a set of Java tools for parsing, fetching and generating all forms of RSS and Atom feeds. The core ROME library is relatively small and depends only on the somewhat creaky old JDOM XML parser. Available separately are modules to support various feed extensions such as OpenSearch, iTunes, GeoRSS, etc. ROME was originally developed and open sourced by Sun Portal dev team members in 2004.

ROME Propono is a subproject of ROME that supports publishing/editing entries and files to blog servers and AtomPub servers. Propono is made up of three parts: 1) a Blog Client library can publish via either the old lagacy MetaWeblog API or the shiny new AtomPub protocol, 2) an AtomPub client that publishes only via AtomPub and 3) a framework for creating AtomPub servers. Propono was developed by Ramesh Mandava and Dave Johnson, based on code from RSS and Atom in Action and open sourced as part of the Sun Web Developer Pack in 2007.

Abdera is a set of Java tools for working with Atom feeds and AtomPub protocol. This includes a parser, writers, an AtomPub client and a framework for creating AtomPub servers. Abdera's Atom feed parser uses STAX, so it uses less memory and is faster than ROME. Abdera's Atom feed support is more comprehensive than ROME's and it supports signatures, encryption, Atom to JSON, extensions for Threading, Paging, GeoRSS, OpenSearch, GoogleLogin, etc. etc. Abdera was developed by IBM and contribued to Apache in 2006.

Now let's compare frameworks. The pros and cons of ROME are:

• Pro: complete RSS support, all of the dozen various flavors
• Pro: it's generally simple and small, depending only one jar (JDOM)
• Pro: easy to understand and use the AtomPub server framework
• Pro: MetaWeblog API support
• Con: Atom feed support not as comprehensive as Abdera
• Con: parser uses lots of memory, slower, JDOM based
• Con: community not as active, seems to be in maintenance mode (See also Ohloh stats)

The pros and cons of Abdera are:

• Pro: comprehensive Atom feed support, lots more Atom extensions
• Pro: faster more efficient parser
• Pro: In the Apache Incubator with active and growing community (See also Ohloh stats)
• Con: lots of dependencies
• Con: AtomPub server framework poorly documented, overly complex (rewrite coming soon)
• Con: no RSS support (there is something in Abdera contrib, but it's incomplete).

There you have it. ROME and Abdera folks: think that's a fair comparison? Are you a ROME or Abdera user? How would you like to see these frameworks move forward?

There have been some interetsing Atom items recently on James Snell's blog. There was a link to a nice IBM DeveloperWorks article on using Abdera to write Atom feeds to JSON. (I was kinda hoping for an XSL/T, but not matter how you do it, it's a definitely feature that belongs in Abdera.) And there's a good quote from Adrian Sutton's blog post about the Atom features in IBM's Roller and Abdera based Lotus Connections product. And most recently, James linked to the new Google Feed Server project: an Abdera based AtomPub server from Google. All good stuff.

Gotta say, Abdera's looking better and better. It's got the features (IRI support, encrytion, pluggable auth, STAX parsing, etc.) and it's got Dan and appears to have some good momentum going. At this rate, I'm not sure how much more work I'll be putting into ROME Propono. If somebody were to, just for example, contribute an Abdera based AtomPub implementation to Roller, I might have to stop entirely.