All of lore.kernel.org
 help / color / mirror / Atom feed
From: Shawn Pearce <spearce@spearce.org>
To: git <git@vger.kernel.org>
Subject: Re: RFC: Resumable clone based on hybrid "smart" and "dumb" HTTP
Date: Wed, 10 Feb 2016 12:11:46 -0800	[thread overview]
Message-ID: <CAJo=hJuRxoe6tXe65ci-A35c_PWJEP7KEPFu5Ocn147HwVuo3A@mail.gmail.com> (raw)
In-Reply-To: <CAJo=hJtHgE_vye_1sPTDsvJ0X=Cs72HKLgRH8btpW-pMrDdk9g@mail.gmail.com>

On Wed, Feb 10, 2016 at 10:59 AM, Shawn Pearce <spearce@spearce.org> wrote:
>
> ... Thoughts?

Several of us at $DAY_JOB talked about this more today and thought a
variation makes more sense:

1. Clients attempting clone ask for /info/refs?service=git-upload-pack
like they do today.

2. Servers that support resumable clone include a "resumable"
capability in the advertisement.

3. Updated clients on clone request GET /info/refs?service=git-resumable-clone.

4. The server may return a 302 Redirect to its current "mostly whole"
pack file. This can be more flexible than "refs/heads/*", it just
needs to be a mostly complete pack file that contains a complete graph
from any arbitrary roots.

5. Clients fetch the file using standard HTTP GET, possibly with
byte-ranges to resume.

6. Once stored and indexed with .idx, clients run `git fsck
--lost-found` to discover the roots of the pack it downloaded. These
are saved as temporary references.

7. Client runs incremental fetch, and then deletes the temporary
references from 6.


An advantage to this process is its much more flexible for the server.
There is no additional pack-*.info file required. GC can organize
packs anyway it wants, etc.

To make step 4 really resume well, clients may need to save the first
Location header it gets back from
/info/refs?service=git-resumable-clone and use that on resume. Servers
are likely to embed the pack SHA-1 in the Location header, and the
client wants to use this on subsequent GET attempts to abort early if
the server has deleted the pack the client is trying to obtain.

  reply	other threads:[~2016-02-10 20:12 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-10 18:59 RFC: Resumable clone based on hybrid "smart" and "dumb" HTTP Shawn Pearce
2016-02-10 20:11 ` Shawn Pearce [this message]
2016-02-10 20:23   ` Stefan Beller
2016-02-10 20:57     ` Junio C Hamano
2016-02-10 21:22       ` Jonathan Nieder
2016-02-10 22:03         ` Jeff King
2016-02-10 21:01     ` Jonathan Nieder
2016-02-10 21:07       ` Junio C Hamano
2016-02-11  3:43       ` Junio C Hamano
2016-02-11 18:04         ` Shawn Pearce
2016-02-11 23:53       ` Duy Nguyen
2016-02-13  5:07         ` Junio C Hamano
2016-02-10 21:49   ` Jeff King
2016-02-10 22:17     ` Jonathan Nieder
2016-02-10 23:03       ` Jeff King
2016-02-10 22:40     ` Junio C Hamano
2016-02-11 21:32     ` Junio C Hamano
2016-02-11 21:46       ` Jeff King
2016-02-13  1:40     ` Blake Burkhart
2016-02-13 17:00       ` Jeff King
2016-02-14  2:14     ` Shawn Pearce
2016-02-14 17:05       ` Jeff King
2016-02-14 17:56         ` Shawn Pearce
2016-02-16 18:34         ` Stefan Beller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAJo=hJuRxoe6tXe65ci-A35c_PWJEP7KEPFu5Ocn147HwVuo3A@mail.gmail.com' \
    --to=spearce@spearce.org \
    --cc=git@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.