Last modified: 2014-10-25 17:19:56 UTC
It would be useful to be able to return the size of a diff and/or cache status before actually preloading it via the browser. For example: http://en.wikipedia.org/w/api.php?action=query&prop=revisions&revids=279481248&rvdiffto=279702980 This generates 168k gzipped, but in actuality it is 5.5 megs plaintext. With &rvdiffinfo it would be nice, if the diff is already cached, to show the size (and possibly titles, cache key, other diff info) without necessarily fetching it. I am ambivalent on whether it would be a good idea to return the info if the diff is not cached, as that would involve generating it, and might be a bad practice (that they could then generate huge diffs without having to download them). Probably if it is not cached, the user should get a cached=false or notcached="" parameter, so they know they must &rvdiffto to generate it first.
I wonder if there is any relation to (fixed) https://bugzilla.wikimedia.org/show_bug.cgi?id=37301 for user contribs and if that fixed one would make it easier to implement this request here?