dumb HTTP things I want to do

From: Eric Wong <e@80x24.org>
To: Jeff King <peff@peff.net>
Cc: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>,
	git@vger.kernel.org, "Junio C Hamano" <gitster@pobox.com>
Subject: dumb HTTP things I want to do
Date: Tue, 14 May 2019 12:13:50 +0000	[thread overview]
Message-ID: <20190514121350.jugxtegpvcxr4vjs@dcvr> (raw)
In-Reply-To: <20190514115047.oncvfq24fhnp64re@dcvr>

Eric Wong <e@80x24.org> wrote:
> Jeff King <peff@peff.net> wrote:
> > That's my reading, too, but I didn't want to be responsible for
> > regressing some obscure case. At least Eric seems to _use_
> > update-server-info. ;)
> 
> I also have something else on my mind for abusing info files with :>
> (another email)

I'm not sure when/if I'll have time for this; but this ought to
be possible:

	GIT_DIR=$HTTP_URL git <any read-only command>

And possible without existing admins to setup or change
anything on their server.

Right now, I could do it by setting up a WebDAV server
and using fusedav[1] on the client.

But, not everybody runs a WebDAV server which allows PROPFIND
for listing files...  However, info/refs and objects/info/packs
can give us all the info we need without needing PROPFIND.  All
we'd need is the common GET/HEAD HTTP methods for read-only
access.

git doesn't need mmap; and curl + Range requests ought to be
able to get us what we need to emulate pread.  It'd be great for
low-latency LANs, maybe not so great with high latency; but
probably better in many cases than cloning a giant repo to cat
one blob.

Also, cloning on a static bundle ought to be doable with:

	git clone $REMOTE_OR_LOCAL_PATH/foo.bundle

And yeah, it also sucks that bundles double storage overhead
for admins; it would be nice if I could use bundles as alternates
or packs...

Anyways, all of this is probably a lot of work and I don't hack
much, anymore.

[1] I have many patches for fusedav, and the debian maintainer
    seems dead, and upstream's moved on: https://bugs.debian.org/fusedav
    davfs2 can't do Range requests, so it won't work for big repos...