Re: [GSoC update extra!] git-remote-svn: Week 8

From: Sam Vilain <sam@vilain.net>
Date: Jun 30, 2010, 01:51 UTC
Message-ID: <1277862665.23613.8.camel@wilber>
In-Reply-To: <20100624180752.GA1642@burratino>

On Thu, 2010-06-24 at 13:07 -0500, Jonathan Nieder wrote:

> operation.  In other words, it needs the tree for
> http://path/to/some/svn/root/branches@r11.  This does not correspond
> to a single git tree, since the content of each branch has been given
> its own commit.

I wrote at length about this near the beginning of the project; essentially, figuring out whether particular paths are roots or not is not defined, as SVN does not distinguish between them (a misfeature cargo culted from Perforce). It becomes a data mining problem, you have this scattered data, and you have to find a history inside.

As I recommended before, it probably makes more sense to keep a "remote tracking" branch which mirrors the *entire* repository, and sort out efficient ways to convert SVN revision paths like the above into tree IDs.

I consider it very important to separate the data import and tracking stage from the data mining stage.

Once the data mining stage is well solved, then it makes sense to look at ways that a tracking branch which only tracks a part of the Subversion repository can be achieved. In the simple case, where no repository re-organisation or cross-project renames have occurred it is relatively simple. But in general I think this is a harder problem, which cannot always be solved without intervention - and so not necessary to be solved in short-term milestones. As you are discovering, it is a can of worms which you avoid if you know you always have the complete SVN repository available.

Sam