During development of the new API, the old query.php was left in place on Wikimedia’s sites to provide backwards-compatibility for tools and user scripts using it.
However it’s a bit of a burden to keep it around — being nearly unmaintained it suffers from “bitrot“:
- Queries sometimes break due to backend changes
- Security problems are sometimes discovered and must be patched
We’ve been reluctant to just turn it off since some user scripts still use it (Lupin’s Popups are rumored to be the most popular such), but I’d like to go ahead and plan to kill it.
I’m currently scheduling the Death of query.php for Monday, August 25 — a little less than 4 weeks from today.
This gives interested parties a chance to either migrate their scripts to the current API ahead of time, or to start work on an adaptor to replace query.php — transforming queries to send them to the new API and transforming the results back to a format compatible with the old one.