Context and Scope

Business Context

Neighbour	Description
Tools and Bots	Applications and Bots (opens new window) interacting with the Repo's data programmatically
Wikibase Client	Wikibase Clients are MediaWiki applications consuming the Wikibase Repository's data. In Wikidata's case these would include Wikipedia, Wiktionary and others.
Wikidata Query Service	A SPARQL endpoint and graphical user interface for querying the Repo's data.

Technical Context

Wikibase Repository is being developed as a set of MediaWiki extensions, but unlike Wikibase Client, they are not "plugins" that live inside MediaWiki, adding functionality to it. Instead, Wikibase Repository should be considered a system of its own, which is reflected in this diagram by not regarding MediaWiki as an external system to Wikibase Repository. See further details on this decision in the Solution Strategy section.

TIP

Note that updates to the Query Service from the Repo will use either Recent Changes or the event stream via EventLogging and EventGate, not both. Wikidata uses the event stream, while most third party Wikibase setups use an updater that polls the Recent Changes page.

Component	Description
Entity UI and Special Pages	These are the main web user interfaces for viewing and editing Entity data
RdfDumpGenerator	Generates an RDF file from the Repo's Entities
MW Recent Changes (opens new window)	A MediaWiki page listing the most recent edits
MW EventLogging (opens new window)	Backend-agnostic logs of structured event data
EventGate (opens new window)	An EventLogging backend which in production is backed by Kafka
Repo DB	The SQL database containing Entity data
Entity edit hooks	Hooks that get triggered when an Entity is edited
UpdateRepo	Updates Sitelinks when the sitelink target is moved or deleted on the Wikibase Client
API	The Repo's actions on the MW Action API (opens new window) for editing Entities and reading Entity (meta) data