Re: [PATCH v3] upload-pack: send shallow info over stdin to pack-objects

From: Duy Nguyen <pclouds@gmail.com>
Date: Mar 8, 2014, 00:08 UTC
Message-ID: <CACsJy8AcYBXi6LjyJDeEnogPTXfqYXqijXaLY=bUgNnd4cT_Fg@mail.gmail.com>
In-Reply-To: <xmqq8uslvp86.fsf@gitster.dls.corp.google.com>

On Sat, Mar 8, 2014 at 1:27 AM, Junio C Hamano <gitster@pobox.com> wrote:

Show 21 quoted lines

>>> On the receive-pack side, the comment at the bottom of
>>> preprare_shallow_update() makes it clear that, if we wanted to use
>>> hooks, we cannot avoid having the proposed new shallow-file in a
>>> temporary file, which is unfortunate.  Do we have a similar issue on
>>> hooks on the upload-pack side?
>>
>> No. I don't think we have hooks on upload-pack.
>
> The question was not only about "do we happen to work OK with the
> current code?" but about "are we closing the door for the future?"
>
> If we ever need to add hooks to upload-pack, with the updated
> approach, its operation will not be affected by the temporary
> shallow file tailored for this specific customer.  Which I think is
> a good thing in general.
>
> But at the same time, it means that its operation cannot be
> customized for the specific customer, taking into account what they
> lack (which can be gleaned by looking at the temporary shallow
> information).  I do think that it is not a big downside, but that is
> merely my knee-jerk reaction.

When upload-pack learns about hooks, I think we'll need to go back with --shallow-file, perhaps we a secure temporary place to write in. I don't see another way out. Not really sure why upload-pack needs customization though. The only case I can think of is to prevent most users from fetching certain objects, but that does not sound realistic..

Show 8 quoted lines

>>> Nothing for Documentation/ anywhere?
>>
>> Heh git-pack-objects.txt never described stdin format. At least I
>> searched for --not in it and found none. So I gladly accepted the
>> situation and skipped doc update :D
>
> To pile new technical debt on top of existing ones is to make things
> worse, which we would rather not to see.

Of course.. So what should we do with this? Go with this "no temp file" approach and deal with hooks when they come, or prepare now and introduce a secure temp. area?

-- 
Duy