Re: Converting to Git using svn-fe (Was: Speeding up the initial git-svn fetch)

From: Stephen Bash <bash@genarts.com>
Date: Oct 15, 2010, 14:50 UTC
Message-ID: <2196050.492435.1287154246295.JavaMail.root@mail.hq.genarts.com>
In-Reply-To: <AANLkTi=PwLmKSb_gF=k+xVSZfM1CDCFZFZdR7pLgh6t6@mail.gmail.com>

> Thanks for the very interesting read. It seems like a (very) long
> pipeline though, I wonder how we can make this not only easier, but
> also more streamlined for git-remote-svn.

The process can certainly be streamlined.  As is often the case, this process was created via the "just make it work" mentality (and a barely passable knowledge of git).  Now that I'm a little more comfortable with git and it's basic objects, I think I could probably create a new process that does a single pass through the svn-fe created repository and creates a new repository with the correct history (and some other nice features that come with any 2.0).

But I'm also looking at this from a one-time conversion view.  I had a couple of conversations with Ram that showed me my point of view is very narrow compared to the larger git-remote-svn effort...

Show 5 quoted lines

> Do you have any suggestions
> on how you would prefer this to be done in git-remote-svn? (Main
> advantage for git-remote-svn might be that we can use git notes to
> store commit conversion information, instead of having to mine commit
> messages.)

I think using notes is a better way to associate conversion information with commits, but I would probably still end up mining the notes to create some sort of svn to git mapping...  Correct me if I'm wrong, but I don't see how notes would help me get from an svn rev to a git sha (a common practice for tickets and wiki links in our organization).  The latter is more a job for tags, and while that would be possible, that more than doubles the number of objects in the repository (I have a good percentage of SVN revs that turned into multiple git commit objects).

But otherwise, my suggestions are (unfortunately) rather naive.  "Make it work like git-svn, but faster" :)  I can offer the warning to watch out for cross-branch (subdirectory/file) copies; we had a lot of those in our SVN repository, and I still don't know if there's anyway in Git to represent that operation...  And obviously even if I did have/use the svn merge information, svn merges don't map directly to git merges... but I'm guessing I'm not saying anything you haven't already thought about.

I guess after that I should add that I'm happy to help, I'm just not sure where my experience maps to the on going effort.

Thanks, Stephen