Integration with Mediawiki sites

Drupal's wiki features at this point are already pretty impressive, especially compared to what was available just a couple of years ago. My main personal interest, however, is not in building wiki functionality into a Drupal site, but rather in enabling cross-site integration between Drupal sites and Mediawiki sites.

One advantage to this sort of cross-site integration is that it could enable Drupal sites to leverage content from existing, already content-rich wikis such as Wikipedia.

I've been doing this for some time between two of my websites -- PRWatch.org, which is currently running Drupal 4.7 (soon to be 5.2), and SourceWatch.org, which is currently running Mediawiki 1.8.2. The advantages to Mediawiki are that it is the same software that runs Wikipedia, and is therefore already feature-rich, has its own developer community, can handle lots of traffic, and lots of people already know how to use the interface. I find Drupal an ideal platform for blogging, and adding customized features is much easier on Drupal than on Mediawiki, whether through installing available contrib modules or through writing my own. For the wiki end of things, however, I think it would be difficult to emulate everything Mediawiki can offer, including namespaces, templates, user watchlists, etc.

For integration thus far, I've got PRWatch.org and Sourcewatch.org sharing the same user list, so that people can log in to either site under the same username and password. I'm doing this right now using a hacked-up version of a Mediawiki extension called "EMU." In the future, however, I'd like to go further and create a more seamless single signon system. Right now user accounts are synchronized, but people still have to log in separately on each site. I'd like to see if something along the lines of Drupal's cosign or Site Pass modules can enable users to to log in once and then be able to jump back and forth between the two sites without needing to log in a second time.

For cross-linking from PRWatch.org to SourceWatch, I wrote the interwiki module (now in Drupal contribs), which provides an easy way of linking to articles on the wiki by simply putting two square brackets around a phrase. My main wiki is Sourcewatch, but I can also link to Wikipedia articles by putting "w:" in front of the phrase being linked, e.g., w:ice cream. More recently, I've found a combination of my interwiki module and Drupal's PEAR Wiki filter module to enable other features of Mediawiki syntax, such as equals signs for subheads, while still having double-bracketed phrases point to Sourcewatch articles rather than create new articles within PRWatch. This makes it easy to reference Sourcewatch articles when blogging from the Drupal site, and it's also easy to copy-and-paste text between the two sites. We're also starting to work now with other organizations to help them set up their own, similarly-configured Drupal-powered "Sourcewatch partner sites." The idea is that they can brand the Drupal site however they want and use all of Drupal's community-building tools, while collaborating with other Sourcewatch partners in using a shared wiki for collaborative research and referencing purposes.

I've also started experimenting with ways of transcluding content (either whole articles, or sections of articles) from Mediawiki into Drupal. For example, I've tried using thickbox so that links to Sourcewatch articles pop up INSIDE Drupal pages. I'm also interested in finding a way of using Mediawiki's user watchlists as a means of displaying targeted subsets of the full wiki inside other sites. This could be useful also as a way of selectively presenting desired content from Wikipedia within a Drupal site. Suppose, for example, that you want to create a Drupal site devoted to tennis, and within it you wanted to have a section that mirrors just Wikipedia's tennis-related related articles. To do so, you could create a Wikipedia user account, add the tennis articles to your watchlist, and then mirror just those articles on your Drupal site. (I think this feature could be especially powerful if used in combination with Drupal groups.)