I attempted to install Wikibase the other day and made a fun discovery.
Installing it properly requires the following (12) extensions:
WikibaseClient
Wikibase DataModel
WikibaseLib
Wikibase Repository
DataValues
DataTypes
ValueParsers
ValueView
ValueValidators
ValueFormatters
Diff
Scribunto
And the following optional (2) extensions:
Universal Language Selector
Babel
Soon it will also require at least the following (4) extensions:
Ask
Wikibase Query
Wikibase Database
Wikibase QueryEngine
To fully deploy wikibase in a way that will work like wikidata, it will
take at least 18 extensions, all of which are versioned differently, and
are broken out in this manner to be used as libraries.
What this is subtly doing is adding another dependency chain into
MediaWiki: extension libraries. Since these extensions are meant to be used
as libraries, other extensions will eventually do so and admins will have
to worry about not only extension compatibility with MediaWiki (an already
nearly impossible task), but will also need to worry about extension
dependency with extension libraries. The compatibility matrix for this is
going to be terrible and exacerbates one of MediaWiki's biggest problems
for admins.
Quite a few of these should be core functionality or if they can't properly
pass review they should be removed. For legitimate library-like extensions
I have no constructive alternative, but there must be some sane alternative
to this.
- Ryan