On Sun, Apr 24, 2016 at 1:39 AM, Brion Vibber bvibber@wikimedia.org wrote:
On Sunday, April 24, 2016, Daniel Friesen daniel@nadir-seen-fire.com wrote:
Tangentially related, Chrome plans to drop support for SPDY and go HTTP/2 only this year, Edge already dropped support for SPDY, and other browsers may too. So before this is actually implemented, Wikimedia might want to upgrade web server software to support HTTP/2 (currently MediaWiki.org looks to only be using SPDY).
Though a sad realization is that IE11 only supports HTTP/2 on Windows 10 (other Windows versions will only support SPDY) and same goes for Safari only doing HTTP/2 on OSX 10.11+. Which is relevant because some webservers like Nginx intentionally drop the SPDY implementation in the release they implement HTTP/2.
Yeah, transition will be "fun". We need to make sure we either have something that works well enough on both http 1.1 and 2 if we can't keep SPDY for the slightly older browsers, or play fun games with variant caching so we have a concatenated loader setup and a non-concatenated loader setup. :)
For those not familiar, SPDY is roughly the experimental predecessor of the new HTTP/2, providing most of the same benefits but not quite compatible with the final standard. As a transitional technology it's getting dropped from some of the things that are updating, but we're going to see some folks stuck on browser versions in the middle with SPDY but no HTTP/2... And others with older browsers that support neither:
http://caniuse.com/#feat=spdy http://caniuse.com/#feat=http2
We use Nginx for TLS and SPDY termination, which makes supporting both SPDY and HTTP/2 unfeasible. The plan is to replace SPDY support with HTTP/2 on or before Chrome does it on May 15 http://blog.chromium.org/2016/02/transitioning-from-spdy-to-http2.html. This is tracked in Phabricator as T96848 https://phabricator.wikimedia.org/T96848.
The browsers that support SPDY are all evergreen (self-updating by default), so I expect the migration to HTTP/2 will be quicker than what we are accustomed to with browser technology. But HTTP 1.1 won't go anywhere for an aeon.