Re: [PATCH] update-server-info: avoid needless overwrites

From: Eric Wong <e@80x24.org>
Date: May 14, 2019, 11:50 UTC
Message-ID: <20190514115047.oncvfq24fhnp64re@dcvr>
In-Reply-To: <20190514094729.GA12256@sigill.intra.peff.net>

Jeff King <peff@peff.net> wrote:

> Yeah, I think there's sort of an open question here of who is calling
> update-server-info when nothing got updated. I think the only place we
> call it automatically is via receive-pack, but I'd guess Eric runs it as
> part of public-inbox scripts.

Correct. post-update doesn't get run because public-inbox relies on fast-import. I have mirrors using "git fetch", which also doesn't call post-update, either so I was calling update-server-info in my mirror script.

Since more people have taken an interest in mirroring things, I figured I'd make "public-inbox-index" (the script which updates the Xapian and SQLite indices) call update-server-info itself.

That way, it's simpler to mirror (v1) inboxes:

  git fetch && git update-server-info && public-inbox-index

becomes:

  git fetch && public-inbox-index

That's a huge savings in cognitive overhead.

So, my eventual goal for this is we get to the point where any git operation which changes refs will automatically update info/refs if it exists.

Ditto for objects/info/packs on any pack changes.

This, like my bitmap-by-default change is among the things I'm trying to make it easier for more users to start self-hosting (including mirroring) any type of git repo.

Anyways, I am far from knowledgeable about the locking discussion for git, though :x

> 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)