Daniel Kinzler wrote:
Hi all
The Memento Project http://www.mementoweb.org/ (including the Los Alamos National Laboratory (!) featuring Herbert Van de Sompel of OpenURL fame) is proposing a new HTTP header, X-Accept-Datetime, to fetch old versions of a web resource. They already wrote a MediaWiki extension for this http://www.mediawiki.org/wiki/Extension:Memento - which would of course be particularly interesting for use on Wikipedia.
Do you think we could have this for Wikimedia project? I think that would be very nice indeed. I recall that ways to look at last weeks main page have been discussed before, and I see several issues:
- the timestamp isn't a unique identifier, multiple revisions *might* have the
same timestamp. We need a tiebreak (rev_id would be the obvious choice).
- templates and images also need to be "time warped". It seems like the
extension does not address this at the moment. For flagged revisions we do have such a machnism, right? Could that be used here?
- Squids would need to know about the new header, and by pass the cache when
it's used.
You can't view the main page as it was in the past, because users routinely upload temporary images to display there, so that they can be protected, and then delete them once they're off the page.
Also, we can't have people crawling Wikipedia while requesting old versions, because of the excessive disk seeking and CPU usage that would generate. That's why the history page has a robot policy of noindex, nofollow.
-- Tim Starling