dumps.wikimedia.org should have a machine readable interface for listing all sites, all types of dumps for a given site, and all versions of a given dump. This "web API" could just consist of static JSON files. An index.json in each directory, with file names and descriptions, would be a good start.
|Open||None||T88728 Improve Wikimedia dumping infrastructure|
|Resolved||ArielGlenn||T92966 Machine readable interface for dumps.wikimedia.org|
The Dumps project on Wikimedia Labs is currently using such an API internally in automating the process of archiving to the Internet Archive. I am currently working on exposing this API to the web, so do voice out what you wish to have in this API, thanks!