README

Wikibase extension that allows defining RDF mappings for Wikibase Entities.

Professional Wiki created and maintains Wikibase RDF. We provide Wikibase hosting, Wikibase development, and Wikibase consulting.

The Wikibase Stakeholder Group conceived and funded the extension.

Table of Contents

• Usage
  • REST API
• Installation
• PHP Configuration
• Development
• Release notes

Usage

When the extension is enabled, Item and Property pages show a "Mapping to other ontologies" section. This section is located between the "In more languages" and "Statements" sections.

Users with editing permissions can add, edit, or remove mappings.

A mapping consists of a predicate and a URL. The predicate can only be one out of a preconfigured set of values. The URL has to be valid.

Mapping predicates can be configured via the MediaWiki:MappingPredicates page by anyone with interface-admin permissions. You can also configure mapping predicates via PHP Configuration.

REST API

This extension provides REST API endpoints for getting and setting the RDF mappings for a Wikibase entity.

For more information, refer to the REST API documentation.

Installation

Platform requirements:

• PHP 8.1 or later (tested up to 8.4)
• MediaWiki 1.43 or later (tested up to 1.43)
• Wikibase 1.43 or later (tested up to 1.43)

The recommended way to install Wikibase RDF is using Composer with MediaWiki's built-in support for Composer.

On the command line, go to your wiki's root directory. Then run these two commands:

COMPOSER=composer.local.json composer require --no-update professional-wiki/wikibase-rdf:~2.0

composer update professional-wiki/wikibase-rdf --no-dev -o

Then enable the extension by adding the following to the bottom of your wikis LocalSettings.php file:

wfLoadExtension( 'WikibaseRDF' );

You can verify the extension was enabled successfully by opening your wiki's Special:Version page in your browser.

PHP Configuration

Configuration can be changed via LocalSettings.php.

Allowed predicates

List of allowed predicates.

Variable: $wgWikibaseRdfPredicates

Default: []

Example:

$wgWikibaseRdfPredicates = [
	'owl:sameAs',
	'owl:SymmetricProperty',
	'rdfs:subClassOf',
	'rdfs:subPropertyOf',
];

You can also configure what predicates are allowed via the MediaWiki:MappingPredicates page.

Development

To ensure the dev dependencies get installed, have this in your composer.local.json:

{
	"require": {
		"vimeo/psalm": "^4",
		"phpstan/phpstan": "^1.4.9"
	},
	"extra": {
		"merge-plugin": {
			"include": [
				"extensions/WikibaseRDF/composer.json"
			]
		}
	}
}

Running tests and CI checks

You can use the Makefile by running make commands in the WikibaseRDF directory.

• make ci: Run everything
• make test: Run all tests
• make cs: Run all style checks and static analysis

Alternatively, you can execute commands from the MediaWiki root directory:

• PHPUnit: php tests/phpunit/phpunit.php -c extensions/WikibaseRDF/
• Style checks: vendor/bin/phpcs -p -s --standard=extensions/WikibaseRDF/phpcs.xml
• PHPStan: vendor/bin/phpstan analyse --configuration=extensions/WikibaseRDF/phpstan.neon --memory-limit=2G
• Psalm: php vendor/bin/psalm --config=extensions/WikibaseRDF/psalm.xml

Release notes

Version 2.0.0 - 2025-07-07

• Raised minimum MediaWiki version to 1.43
• Raised minimum PHP version to 8.1
• Translation updates for system messages (thanks @translatewiki and its translator community)

Version 1.1.0 - 2022-11-25

• Added notification about SPARQL store behavior that shows on first edit
• Translation updates for system messages (thanks @translatewiki and its translator community)

Version 1.0.0 - 2022-10-04

Initial release for Wikibase 1.37 with these features:

• Ability to add mappings to Items and Properties via an on-page UI
• Inclusion of mappings in the RDF output
• Configurable relationships (predicates), including configuration UI on MediaWiki:MappingPredicates
• API endpoint to retrieve or update the mappings for an Entity
• API endpoint to retrieve all mappings defined on the wiki
• TranslateWiki integration
• Support for PHP 8.0 and 8.1