Re: Dia on git.gnome.org (experimental repository)

[Owen Taylor <otaylor redhat com>]

On Sun, 2009-01-18 at 18:02 +0100, Hans Breuer wrote:
> As the current maintainer of Dia I finally got around to check the 
> experimental git repository, unfortuantely without much success.
> 
> My first attempt was a checkout (clone) for my main development platform 
> (winxp, please don't shoot me;)) but after failing that I took a look form 
> Linux as well.
> 
> My main question at the moment is (could not find an answer on 
> gnome-infrastructure thread [0] or http://live.gnome.org/GitMigration) :
> 
> Will it be possible for a module maintainer on gnome.org to choose to stay 
> with SVN?

I don't think that's practical. There's a lot of infrastructure
involved; the commit mail, web interface, etc that interact with the
version control system. Supporting multiple different version control
systems long-term would strain an already under-resourced sysadmin team.

> Git from win32
> ==============
> neither named nor anonymous cloning did work for me (works fine from Linux)
> 
> hb HB-T1XP /d/devel/from-git
> $ git --version
> git version 1.5.4.2.1161.g1a6f0
> 
> hb HB-T1XP /d/devel/from-git
> $ git clone ssh://hans git gnome org/git/dia.git dia
> Initialized empty Git repository in d:/devel/from-git/dia/.git/
> Permission denied (publickey).
> fatal: The remote end hung up unexpectedly
> fetch-pack from 'ssh://hans git gnome org/git/dia.git' failed.

This looks to me like something wrong with your ssh key setup on
Windows. If you are using OpenSSH (the default for msysgit, for
example), it will be looking for the files in ~/.ssh/ unix-style, while
with tortoise-svn you would likely be using putty, which handles keys
different.

(You can get msysgit to use plink.exe from the putty distribution
instead, though there are some weirdness there that I haven't quite
figured out.)

Though there is a smaller possibility that somehow the windows ssh setup
is breaking how we restrict the ssh command execution on git.gnome.org
(I can't really test this since my ssh commands there aren't
restricted...) But I wouldn't expect the error above if that was the
case.

Does 'ssh hans master gnome org' work in the same terminal? If not, 
ssh -v may be informative.

Cloning dia via ssh works for me though the repository is larger and
slower to checkout than expected:

$ du -hs /mnt/git-data/svn/{dia,gtk+} /git/{dia,gtk+}.git
150M	/mnt/git-data/svn/dia
1.2G	/mnt/git-data/svn/gtk+
114M	/git/dia.git
88M	/git/gtk+.git

It could be that because the conversion failed partway dia didn't get
repacked at the end.

> hb HB-T1XP /d/devel/from-git
> $ git clone git://git.gnome.org/dia dia
> Initialized empty Git repository in d:/devel/from-git/dia/.git/
> git.gnome.org[0: 209.132.176.202]: errno=No such file or directory
> fatal: unable to connect a socket (No such file or directory)
> fetch-pack from 'git://git.gnome.org/dia' failed.

Somehow xinetd had stopped taking connections on the git part.
Restarting it fixed. I'll keep an eye on that.

> Probably I'm just doing something stupid with the URLs, because my cairo 
> clone still seems to work with the same git version.
> 
> hb HB-T1XP /d/devel/from-git
> $ git clone git://anongit.freedesktop.org/git/cairo cairo.2nd
> Initialized empty Git repository in d:/devel/from-git/cairo.2nd/.git/
> remote: Counting objects: 40543, done.←[K
> remote: Compressing objects: 100% (10625/10625), done.←[K
> remote: Total 40543 (delta 30263), reused 40097 (delta 29878)←[K
> Receiving objects: 100% (40543/40543), 26.84 MiB | 230 KiB/s, done.
> Resolving deltas: 100% (30263/30263), done.
> Checking out files: 100% (1595/1595), done.
> 
> Conversion errors
> =================
> Looking at http://git.gnome.org/cgit/dia/ it appears to me that the
> dia/trunk is not available at all. I assume it should have been mapped
> to 'master', but there the last change is 7 month old regardless of
> quite some activity in Dia trunk since than.
> 
> The last commit shown on master is:
> 
> commit 7fee0d296dc5d674dcf405ee722f32ae67c638f2
> Author: Hans Breuer <hans src gnome org>
> Date:   Sun Jun 29 16:08:33 2008 +0000
> 
>      [Patch from Thomas Harding fixing help generation for non-gnome case]
>      without gnome install to $(helpdocdir) initialize HAVE_XSLTPROC
>      conditionalize on HAVE_GNOME
> 
>      svn path=/trunk/; revision=4079
> 
> The SVN action apparently breaking the conversion was:
> 
> Revision: 4080
> Author: hans
> Date: 18:43:49, Sonntag, 29. Juni 2008
> Message:
> Copied remotely
> ----
> Added : /branches/dia-0-90(Copy from path: /tags/dia_0_90, Revision, 4079

OK, we'll add this to the list of problems we need to investigate. It's
not too surprising that the tool choked on branching from a tag; it's
not exactly a common operation.

> Choosing the right vcs?
> =======================
> In an earlier post Owen was mentioning a lot of "angst" [1] regarding the
> switch from SVN to git, unfortunately I share that angst.
> 
> In the list of possible (distributed) version control systems from my
> limited experience git is the one, which cares less for portability (fair
> enough for being the Linux kernel version control system).
> 
> But for gnome.org where a lot of projects actually do care for portability
> I think there should be official vcs support at least for major platforms 
> we care about. And some usable gui integration would be nice, too [2].

Certainly the cross-platform story for git isn't perfect, but I think it
will just get better:

 - msysgit is very easy to install, if not that easy to use for non-Unix
   users.

 - Some initial tortoisegit code exist. I don't know if it is at all
   usable.

 - There is fairly active work on 'libgit2' - making the internals of 
   git into a library, which has the potential to make a native git
   on windows without cygwin more practical. 
 
- Owen