From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: http-protocol question
Date: Mon, 1 Dec 2014 20:45:22 -0800
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Cc: Git Users <git@vger.kernel.org>
To: Bryan Turner <bturner@atlassian.com>
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Hi,

Bryan Turner wrote:

> The reason I ask is that there is a race condition that exists where
> the ref advertisement lists refs/heads/foo at abc1234, and then foo is
> deleted before the actual upload-pack request comes in.

Can you say more about the context?  For example, was this actually
happening, or is this for the sake of understanding the protocol
better?

I ask because knowing the context might help us give more specific
advice.

Sometimes when people delete a branch they really want those objects
to be inaccessible *right away*.  So for such people, git's behavior
of failing the request unless the objects are still accessible by
some other path is helpful.

A stateful server could theoretically cache the list of objects they
have advertised for a short time, to avoid clients having to suffer
when something becomes inaccessible during the window between the
upload-pack advertisement and upload-pack request.  Or a permissive
server can allow all wants except a specific blacklist (and some
people do that).

Jonathan