On Tue, 2016-04-26 at 20:59 -0700, Stefan Beller wrote: > On Mon, Apr 25, 2016 at 3:10 PM, Stefan Beller <sbeller@xxxxxxxxxx> > wrote: > > On Mon, Apr 25, 2016 at 9:44 AM, David Turner < > > dturner@xxxxxxxxxxxxxxxx> wrote: > > > On Wed, 2016-04-20 at 16:57 -0400, Jeff King wrote: > > > > On Wed, Apr 20, 2016 at 04:46:55PM -0400, David Turner wrote: > > > > > > > > > As you note, it appears that git-daemon does sort-of have > > > > > support > > > > > for > > > > > extra args -- see parse_host_arg. So it wouldn't be hard to > > > > > add > > > > > something here. Unfortunately, current versions of git die on > > > > > unknown > > > > > args. So this change would not be backwards-compatible. We > > > > > could > > > > > put > > > > > a decider on it so that clients would only try it when > > > > > explicitly > > > > > enabled. Or we could have clients try it with, and in the > > > > > event of > > > > > an > > > > > error, retry without. Neither is ideal, but both are > > > > > possible. > > > > > > > > Right. This ends up being the same difficulty that the v2 > > > > protocol > > > > encountered; how do you figure out what you can speak without > > > > resorting > > > > to expensive fallbacks, when do you flip the switch, do you > > > > remember > > > > the > > > > protocol you used last time with this server, etc. > > > > > > Right. > > > > > > [moved] > > > > > If I read this code correctly, git-over-ssh will pass through > > > > > arbitrary > > > > > arguments. So this should be trivial. > > > > > > > > It does if you are ssh-ing to a real shell-level account on the > > > > server, > > > > but if you are using git-shell or some other wrapper to > > > > restrict > > > > clients > > > > from running arbitrary commands, it will likely reject it. > > > > > > Oh, I see how I was mis-reading shell.c. Oops. > > > [/moved] > > > > > > > > > > Which isn't to say it's necessarily a bad thing. Maybe the path > > > > forward > > > > instead of v2 is to shoe-horn this data into the pre-protocol > > > > conversation, and go from there. The protocol accepts that > > > > "somehow" > > > > it > > > > got some extra data from the transport layer, and acts on its > > > > uniformly. > > > > > > OK, so it seems like only HTTP (and non-git-shell-git://) allow > > > backwar > > > ds-compatible optional pre-protocol messages. So we don't have > > > good > > > options; we only have bad ones. We have to decide which > > > particular > > > kind of badness we're willing to accept, and to what degree we > > > care > > > about extensibility. As I see it, the badness options are (in no > > > particular order): > > > > > > 1. Nothing changes. > > > 2. HTTP grows more extensions; other protocols stagnate. > > > 3. HTTP grows extensions; other protocols get extensions but: > > > a. only use them on explicit client configuration or > > > b. try/fail/remember per-remote > > > 4. A backwards-incompatible protocol v2 is introduced, which > > > hits alternate endpoints (with the same a/b as above). This > > > is > > > different from 3. in that protocol v2 is explicitly designed > > > around > > > a capabilities negotiation phase rather than unilateral client > > > -side > > > decisions. > > > 5. Think of another way to make fetch performant with many refs, > > > and > > > defer the extension decision. > > > > I'd prefer 2,3,4 over 1,5. > > > > Speaking about 2,3,4: > > > > Maybe we can do a mix of 2 and 4: > > > > 1) HTTP grows more extensions; other protocols stagnate for now. > > 2) Come up with a backwards-incompatible protocol v2, foccussed > > on > > capabilities negotiation phase, hitting alternative end > > points > > (non http only, or rather a subset of protocols only) > > 3) if HTTP sees the benefits of the native protocol v2, we may > > switch > > HTTP, too > > > > (in time order of execution. Each point is decoupled from the > > others and may > > be done by different people at different times.) > > > > Today I rebased protocol-v2[1] and it was fewer conflicts than > expected. > I am surprised by myself that there is even a test case for v2 > already, > so I think it is more progressed that I had in mind. Maybe we can do > 1) > for now and hope that the non http catches up eventually? > > > [1] https://github.com/stefanbeller/git/tree/protocol-v2 Do you plan to send these patches to the mailing list? What's the next step here? -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html