Blogging Roller

Here is an XSL transform for converting a flat OPML file (like those produced by PlanetPlanet sites), to a Roller Planet config file (with all subscriptions in one group): opml2planet.xsl

Planet SST has converted from PlanetPlanet to Planet Roller. OK, so "Students and former students of the Hasso-Plattner-Institute" is not a big planet, but it is a start.

Planet Roller is a community aggregator, a tool for creating a website that combines related but separately hosted blogs together into one blog with it's own newsfeed. Planet Roller will eventually be part of Roller, but for the upcoming Roller 1.1 release it's in the Roller "sandbox" and will only be available in custom builds. There's also a standalone verion of Planet Roller, which I'll describe below.

Here's some status. I spent most of the week creating the infrastructure needed for configuring and running Planet Roller inside of Roller. That means storing the subscription and group configuration in a database, rather than an XML file. And, it means doing aggregation via a database query rather than spinning through a bunch of hashtables. Once I'm done, we'll have a custom-build of Roller that puts every Roller blog on the system into the aggregator and allows us to add separately blogs into the mix.

Want to try Planet Roller? I've been testing a standalone command-line version of Planet Roller, which I call Planet Tool, by running a site called Triangle Bloggers, which combines a bunch of local blogs in the Raleigh-Durham area. So, one way to try Planet Roller is to visit that site and subscribe to the feed. Triangle Bloggers has been a good testing experience because I've been forced to deal with a wide variety of Atom and RSS feeds. Planet Tool can handle Atom and just about any form of RSS, as long as it has item level publication dates (i.e. must be RSS 0.93 or later).

If you want to try running Planet Tool and creating your own aggregated blog, you can get the tool here: planet-roller-1.1-dev.tar (source is included). If you have Java installed, all you need to do is download it, un-tar it (with tar or Winzip), open a command window, and either run planet-tool.sh or plannet-tool.bat. It reads an XML config file and then generates the HTML and XML files needed for an aggregated blog. To keep your aggregated blog up to date, you'll need to run Planet Tool on a schedule, so run it as a cron job or as a Window Scheduled Task.

For more information on the config file and on page templates see this blog entry:
Rome + Texen = Planet Roller

For more information on how Planet Tool works:
Planet Roller Internals