Extension:RPED

This is the Remote Page Existence Detection (RPED) extension.

In the experimental release
It causes wikilinks to turn blue and link to a remote wiki if the page title exists in a table of page titles present on a remote wiki (e.g. Wikipedia).

In the production-level release
This extension maintains a local copy of a centralized list of names of pages existent on Wikipedia; when parsing a page, wikilinks are colored accordingly. It can also act a server providing the full list and differential updates to it to other wikis that request it. The configuration of the extension can be controlled through a special page. See Extension:RemotePageExistenceDetection/Development notes for more details.

Usage
An authorized user (i.e. a bureaucrat) uses Special:RPED to generate a random 32-digit password that is then sent to the RPED central server. The wiki is then subscribed for page title list syndication and will receive updates (i.e. additions and deletions) every x seconds.

Installation
See Extension:RemotePageExistenceDetection/Proof of concept.

Code
See Extension:RemotePageExistenceDetection/Proof of concept.

Remaining tasks
There is still much to accomplish:
 * ✅ Limit the special page Special:RPED to admins only
 * Provide a more efficient means of importing page name files into the table
 * Provide a means of aborting imports without having to manually drop the control table
 * Provide a means of adding/removing names from the page name table via API
 * Implement green links (rather than just blue)
 * Provide a different method of differentiating "green" links from "blue" (e.g. different font) for accessibility
 * Provide translation into other languages
 * Enable extension to act as a server for the page name list
 * Enable downloads of page name lists from other wikis with the extension