The Wikibase.git package is part of the Wikibase software and consists of three interconnected extensions:

• Wikibase Repository (in the directory repo)
• Wikibase Client (in the directory client)
• WikibaseLib (in the directory lib)

These extensions allow for the creation, maintenance, dissemination, and usage of structured data in MediaWiki.

The repo is the extension for the repository. It allows the creation and maintenance of structured data. This is being used on wikidata.org.

The client is the extension for the client. It allows several MediaWiki instances to use data provided by a Wikidata instance. Usually, you would not use them in a single wiki. This is being used on the Wikipedias.

The lib bundles common code that is used by both the client and the repo.

This package contains three interrelated MediaWiki extensions:

• Wikibase (in the subdirectory repo)
• WikibaseLib (in the subdirectory lib)
• Wikibase Client (in the subdirectory client)

Wikibase depends on various libraries such as DataValues components, and uses Composer to make it easy to install and manage those.

Once you have Wikibase in your MediaWiki extensions directory, add the composer.json of Wikibase to composer.local.json at the root of your mediawiki folder, as documented in MediaWiki's Composer documentation.

It should now look similar to:

{
  "extra": {
    "merge-plugin": {
       "include": [
         "extensions/Wikibase/composer.json"
       ]
    }
  }
}

Then, in the root of your mediawiki folder, run:

composer install

If you already ran composer install during the installation of MediaWiki, run instead:

composer update

When using ways to combine MediaWiki with the extension folders (e.g. symlinks or docker volumes) please make sure that the folders are available to composer in the same structure they are available to the webserver, too.

This will install both Wikibase Client and Repo together on the same wiki.

If you want to only have one or the other, then set $wgEnableWikibaseRepo = false or $wgEnableWikibaseClient to false for the one you don't want to enable.

Wikibase also depends on several JavaScript libraries. They are included in this repository as submodules. To fetch files of these libraries, you might need to run, in the Wikibase extension folder, the following command:

git submodule update --init

Wikibase uses tools to ensure the quality of software developed. To invoke these tools, inside the Wikibase folder, run

composer install
composer run-script test

As this uses development dependencies and custom configuration, executing it from the MediaWiki root folder (via composer run-script test extensions/Wikibase) will not work satisfactorily

Wikibase makes use of frontend software from various eras - resulting in a heterogenous technological landscape.

Some notable (not a comprehensive list) mentions are

• the use of ResourceLoader to
  • allow for concatenation and minification of code neatly organized in separate files
  • translate less to CSS
  • model module inter-dependencies
  • handle delivery to the client through MediaWiki
• use of the Javascript interfaces exposed by MediaWiki; e.g. mw.hook in EntityInitializer
• frontend components making heavy use of jQuery; e.g. for so called experts
• the use of qunit to test this code; e.g. in repo/tests/qunit, available via a special page
• vue.js as a frontend framework; e.g. in data-bridge, the Lexeme extension, and termbox

Wikibase exposes vue as a ResourceLoader module so it can be shared between applications. As ResourceLoader in the production environment does not have access to files only acquired through a Javascript package manager (npm), we keep a copy of its source in our repository.

To update that copy you can run the following command and commit the changes to git.

npm update vue
{
  printf '%s\n' '(function(){'
  cat node_modules/vue/dist/vue.common.prod.js
  printf '\n%s\n' '})();'
} >| lib/resources/vendor/vue2.common.prod.js
git add -f lib/resources/vendor/vue2.common.prod.js

(The surrounding IIFE is necessary to avoid Vue breaking the page in ResourceLoader’s debug mode, see T229390.)

These extensions are part of the Wikibase software created by the Wikidata team for the Wikidata project.

The Wikidata project uses the Wikibase software on its website.