haxx qua non

Here’s how I converted, or moved, a Subversion (svn) repository to a subdirectory in a new git repository, with history (but no branches or tags).

Make the svn repo into a git repo (of course, be careful of the linewraps throughout):

mkdir tmprepo1
cd tmprepo1
git-svn init http://URL/TO/SVN/REPO/trunk --no-metadata
echo 'SVNUSER = Firstname Lastname <USER@DOMAIN>' > ~/svnusers.txt
git config svn.authorsfile ~/svnusers.txt
git-svn fetch
cd ..
git clone tmprepo1 tmprepo2

The svnusers.txt file gets one line for each user that committed to the svn repo, where SVNUSER is the login of the users committing to the svn repo, something like:

jja = John Allison <jja@fakedomain.com>

The clone gets rid of the git-svn specific stuff so the new repo is not tied to the old svn repo.

Move the git version of the old repo into a subdirectory of a new git repo:

Create a new git repo:

mkdir newrepo
cd newrepo
git init
touch junkfile

and commit the junkfile so the repo has something solid in it for remote and subtree to work with:

git add junkfile
git commit -a -m 'create a temporary junk file so git has a good HEAD on its shoulders'

then add the old repo with remote and subtree (see references if you don’t have git-subtree). To add the old svn repo to a subdir of an existing git repo, you just need this part, followed by a “git push“.

git remote add -f tmprepo2 ../tmprepo2
git subtree add --prefix=path/to/new/subdir tmprepo2/master
git remote rm tmprepo2

and cleanup everything:

git rm junkfile
git commit -a -m 'remove temporary junk file'
cd ..
rm -rf tmprepo1
rm -rf tmprepo2
rm ~/svnusers.txt

At this point the git log will look something like:

commit 73cc6e101ffdc7e6e9489cdffc261e7bd49c8f79
Author: John Allison 
Date:   Thu Dec 9 11:08:02 2010 -0700

    remove temporary junk file

commit d9dbcce650d9a1568436baa850e014972ac3b9b2
Merge: 176f205... 7e3df51...
Author: John Allison 
Date:   Thu Dec 9 11:07:21 2010 -0700

    Add 'subdir/' from commit '7e3df510ae8e27e3c8244acd7dff3a5df51c275a'

    git-subtree-dir: subdir
    git-subtree-mainline: 176f205c64e68c13a6699e0aff873582608a4262
    git-subtree-split: 7e3df510ae8e27e3c8244acd7dff3a5df51c275a

commit 176f205c64e68c13a6699e0aff873582608a4262
Author: John Allison 
Date:   Thu Dec 9 11:02:24 2010 -0700

    create a temporary junk file so git has a good HEAD on its shoulders

commit 7e3df510ae8e27e3c8244acd7dff3a5df51c275a
Author: John Allison 
Date:   Wed Nov 24 19:04:58 2010 +0000

    blah blah... all the commits of the old svn repo...

I haven’t done much with my new repo yet. Please let me know if you see any gotchas.
HTH!

References:

• Cleanly Migrate Your Subversion Repository To a GIT Repository
• How to import a svn repository underneath a git repository? (watch the syntax, remote add needs another argument as I have above)
• git-subtreegit-subtree.sh as git-subtree somewhere in your path)

Tags: git, svn

This entry was posted on Wednesday, December 8th, 2010 at 5:59 pm, was last modified on Thursday, July 14th, 2011 at 11:34 am, and is filed under tech. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.