net/http: support HTTP/3

[johanbrandhorst]

I searched for an issue to track progress of implementing HTTP/3 in the standard library but couldn't find one, so I'm opening this new issue to track this (presumably inevitable) effort.

HTTP/3 is still an IETF draft, so there's not too much point starting work on this yet. The relevant spec is (currently) available here: https://quicwg.org/base-drafts/draft-ietf-quic-http.html.

Some questions we may want to answer before any work starts:

1. Should work on this start in one of the x repos, like HTTP/2 did?
2. What if any existing libraries can be used as a base for the new HTTP/3 work?

Of note is an existing attempt at implementing QUIC and HTTP/3 in pure go: https://github.com/lucas-clemente/quic-go.

[dsymonds]

Cloudflare now supports HTTP/3, and Chrome and Firefox will shortly start supporting it: https://blog.cloudflare.com/http3-the-past-present-and-future/

[rajveermalviya]

Not to say we're in a race, but node has started implementing quic protocol in a draft PR.

Reference

Now, some bad opinions (if the go team is accepting them):

• net package - dedicated raw quic protocol API, just as tcp/udp?
• net/http package - http/3 server to be enabled explicitly from an environment variable but http/2 & lower supported implicitly using port reuse between udp (quic;http3) & tcp (http2/http1.1) sockets?

[trivikr]

but node has started implementing quic protocol in a draft PR.

Correction: The Node.js QUIC implementation began back in Q1 2019, the draft PR is the result of all that work nodejs/node#23064

[vyrwu]

Is there any progress on this? There are some existing open-source libs like quic-go that can be used for experimenting with quic, but it would be really neat to have something experimental from the std go lib.

[hekmon]

🚀
https://blog.chromium.org/2020/10/chrome-is-deploying-http3-and-ietf-quic.html

[hherman1]

Has there been any word from leadership on whether or not this will be supported?

[ianlancetaylor]

I'm not sure which leadership you are asking about.

I think it's clear that Go must support HTTP/3. This issue is a good place to record the work that needs to be done. But it is one thing to say "we must do this" and it is a very different thing to say "this is how it will be done."

[hherman1]

Sorry I’m not sure how that came off, I was just wondering if there was any official word on if this will be supported. Couldn’t find any on the issue tracker. Thanks for the quick answer though!