Main components:
- Wikimedia Badges (a MediaWiki extension)
Problem:
The sidebar link to Wikimedia Commons on various Wikipedias currently uses P373 ("commons category"). It would be better to use the interwiki sitelinks to Commons instead.
This is one of the blockers for the eventual deletion of P373 ("commons category") from Wikidata - see the ongoing discussion at https://www.wikidata.org/wiki/Wikidata:Properties_for_deletion#Property:P373
Solution:
To use the interwiki sitelinks to Commons the logic would be:
- If there is a sitelink to Commons in the attached Wikidata item, use that (optional: unless it is to a gallery page)
- If there is a P910 ("topic's main category") value, follow that to the category item and use the sitelink to Commons from there
- If there is a P1754 ("category related to list") value, follow that to the category item and use the sitelink to Commons from there
- If there is a P373 ("commons category") value use this as a last fallback
- Otherwise, display nothing.
This follows the logic of the "_getCommonslink" function of https://commons.wikimedia.org/wiki/Module:WikidataIB - which is used to display the links in https://en.wikipedia.org/wiki/Template:Commons_category .
Notes:
- As this is specific code used for the Wikimedia projects only, it should probably sit in the Wikimedia Badges extension, like the current P373 code (see T94989).
- The exact logic for getting “the” P910/P1754 value is the same as in the current P373 code (first string-valued best-rank statement).
Acceptance criteria:
- This works as described (see "solution").
- This needs to be able to cope with P373 being deleted without breaking things (and ideally it should be easy to remove the P373 fallback in that case).
Community communication:
- Announce to the community in our wiki summary while we work on it.
- Announce on project chat / let Mike announce.