On Sat, Jan 07, 2023 at 09:57:06AM -0700, Shawn Heisey wrote: > On 1/7/23 09:41, Shawn Heisey wrote: > > That's really cool. But I have an oddity I'd like to share and see if > > it needs some work. > > Semi-related but separate: I have this line in that frontend: > > stats uri /redacted > > Which works well ... but it never switches to http/3. The alt-svc header > that the frontend specifies is not in the response, even if I move that > config before stats. > > http-response add-header alt-svc 'h3=":443"; ma=7200' > > That's not causing me any problems ... it's not like http/2 is slow. :) But > I did want to mention it, see if you might want to change it. I suspect > that for the stats uri there is a lot of frontend config that is ignored.
Indeed, stats intercept the request and response processing and produce a response directly. You may even remember that years ago it was not even possible to support compression nor keep-alive due to this. Nowadays we have to keep this behavior because of the numerous deployed configs which assume that http-response apply to incoming responses from servers. However there's a solution nowadays, you can use "http-after-response" instead of "http-response". It will apply *after* the response, and will happily overwrite stats, redirects and even error pages. I'd say that it's the recommended way to place alt-svc now. /me just realises that I should update the example on the haproxy.org main page by the way. Willy
