I'm investigating cache purge in nginx and currently we have some success with this patch: http://labs.frickle.com/nginx_cache_purge/. The reason I said "some" is the patch works normally but blows out (the message was like "the file to purge is too small...")when the nginx process has been restarted and the cache to purge was created by the previous nginx process. The patch is also a little out of of sync with the latest nginx.
My question is if there is a roadmap for nginx to add an official support for a purge mechanism.
If the feature is still far in the future, I'd appreciate that people could share their ways of accomplishing the goal in practice.