Extension:InterwikiMap

InterwikiMap updates the local interwiki table with the contents of an interwiki map retrieved from other wiki(s). It can be configured to update the table every x seconds and/or when authorized users trigger it via Special:InterwikiMap. It also automatically updates whenever MediaWiki:Interwiki-whitelist or MediaWiki:Interwiki-blacklist are revised. The whitelist contains a map of pages that will be added to, and remain in, the interwiki table regardless of the maps retrieved from the remote wikis. The blacklist contains a map of pages that will be removed from the interwiki table. Every time the table is updated by this extension, MediaWiki:InterwikiMapBackup is updated by the maintenance script. Thus, you keep a page history of all changes to the interwiki table.

You can select whatever wikis you want to poll; if you select more than one, it will poll all of them and merge all the lists together, resolving any conflicts in favor of the wikis later in the  array. If retrieval or decoding of the results of the siprop=interwikimap API module fails on any of them, the entire update will be aborted; this is because you need the entire combined list in order to know which interwiki links to remove from the local interwiki table.

MediaWiki:InterwikiMapBackup is only supposed to be edited by the maintenance script (although it won't break anything if someone else edits it, it'll leave you with a useless revision in the history that doesn't reflect an actual change to the interwiki table). Therefore, you might want to change $wgInterwikiMapBackupPage to instead use a page outside the MediaWiki: namespace (e.g. to Project: or mainspace), revise the settings in $wgRestrictionLevels accordingly, and protect the page from editing by well-being sysops. You might also put explanatory notes at MediaWiki:Editnotice-8-InterwikiMap‎‎Backup (or whatever would be the appropriate page; see Help:Edit notice), MediaWiki:Editnotice-8-Interwiki-whitelist, and MediaWiki:Editnotice-8-Interwiki-blacklist.

Download InterwikiMap

 * Download the latest version of InterwikiMap (once it gets added to Git)
 * Create a folder in the extensions folder named InterwikiMap
 * Move the files to the extensions/InterwikiMap/ folder

Install SyntaxHighlight_GeSHi and ViewFiles

 * Edit LocalSettings.php in the root of your MediaWiki installation, and add the following line near the bottom:

Configuration
Change these settings to your liking, making sure that you include them in LocalSettings.php after the require_once line installing the extension.

Usage
Your control of your interwiki table is by three means: (1) changing  and the other configuration settings; (2) editing your whitelist; and (3) editing your blacklist. Doing either of the latter two, or visiting Special:InterwikiMap, will cause the remote wikis to be polled and the interwiki table to be updated if necessary. Also, when other pages on your wiki are revised, a check will be done to see whether it's time for the periodic polling of the remote wikis.

Whitelist
Adding an interwiki to your whitelist will add it to your interwiki table, regardless of what is on the remote wiki's interwiki map (or on your own blacklist). Whitelist entries are listed in this format, in which any line that doesn't start with a | will be ignored, and the || indicates the break between prefix and url:
 * wikipedia || en.wikipedia.org

Blacklist
Adding an interwiki prefix to your blacklist will remove it from your interwiki table, regardless of what is on the remote wiki's interwiki map. Only put the prefix (not the url):
 * wikipedia

Changelog

 * 1.03: Made Special:InterwikiMap a restricted special page. Added option for $wgInterwikiMapRemoteWikiUrls to be a string rather than an array. Added support for MediaWiki 1.21's Revision::getContent( Revision::RAW ).
 * 1.02: Added a check to make sure that interwiki prefixes that conflict with namespaces aren't added.