Semantic MediaWiki under Debian

Installing Semantic MediaWiki (SMW) under Debian

Installation consists of these simple steps:

1) Use Aptitude to install package mediawiki-semediawiki (under Lenny that's version 1.2-1)

2) Adjust your namespaces - since we haven't modified the MediaWiki namespaces relative to the original Debian installation, we don't need that.

3) Edit the file /etc/mediawiki-extensions/extensions-available/SemanticMediaWiki.php. All you need to do is change the string for enableSemantics from localhost to the hostname of your server:

<?php
include_once('extensions/SemanticMediaWiki/includes/SMW_Settings.php');
enableSemantics('dworkin.saruman.biz');
?>

Actually, the string for enableSemantics is an identifier, needed to identify any exported data. The Semantic MediaWiki website suggests using the server's host name for this purpose (if you have multiple hostnames, just pick any one of them).

4) Enable the SMW extension, by creating a link to it under /etc/mediawiki-extensions/extensions-enabled:

cd /etc/mediawiki-extensions/extensions-enabled/
ln -s ../extensions-available/SemanticMediaWiki.php

By the way, this should also work with the MediaWiki extension enabler command:

 mwenext SemanticMediaWiki.php

5) We now run the maintenance script that creates the necessary tables in your MySQL MediaWiki database. This is a two-step affair:
- first set the MW_INSTALL_PATH environment variable to the root of the MediaWiki installation. This path is where LocalSettings.php and index.php are located; most likely it's /usr/share/mediawiki.
- then go to the directory where the SMW maintenance scripts are located, and execute SMW_setup.php.
The sequence will thus look something like this:

MW_INSTALL_PATH=/usr/share/mediawiki
export $MW_INSTALL_PATH
cd /usr/share/mediawiki-semediawiki/maintenance
php SMW_setup.php

The php-script should report setting up some nine tables, named smw_ids, smw_redi2 et cetera. These are the extra MySQL tables that SMW needs.

6) Next, log into your MediaWiki with an account with administrative rights. If you now visit your Special pages, you'll find taht under the section Restricted special pages there is now an entry titled Admin functions for Semantic MediaWiki. Open it, and find two sections:

• Preparing database for Semantic MediaWiki
  Here you'll have to press the button labeled Initialise or upgrade tables; this will initialise the newly created tables. A dull page should appear, reporting actions for each of the nine new tables, and ending with the status message The storage engine was set up successfully.
• Announce your wiki
  Clicking this button is optional; what it will do is post the URL of your wiki on the SMW Registry page over on the SMW site.

That's it! You can now start using SMW.