JuergenKosel / git-svn-mirror

Script collection to mirror all branches from subversion into (shared) git repository

git-svn-mirror

Script collection to mirror all branches from subversion into (shared) git repository.

SVN-REPOSITORY => git svn repository => shared git repository

Workflow

To mirror a svn repository into shared git (bare) repository do the following:

• Init an empty git svn repository with git svn init, as described in man git-svn. For example if you want to mirror http://your-svn-server.example.org/svn/exampleProject, run the following command:

git svn init --stdlayout http://your-svn-server.example.org/svn/exampleProject exampleProject

• In case you want to avoid to introduce binaries from svn into git, as suggested for example in migrate-other-systems-to-git, then you should use a git svn init command similar to this one:

git svn init --stdlayout --ignore-paths='.(dll|exe|lib|pdb|so[\.\d]*|a)$' http://your-svn-server.example.org/svn/exampleProject exampleProject

• The regular expression in the example above matches the following file name endings:
  • *.dll
  • *.exe
  • *.lib
  • *.pdb
  • *.so.1.2.3
  • *.a
• Before you fetch for the first time from the svn repository into the git svn repository, you need to add some configuration to the git svn repository. Therefore run the helper script configGitSvnRepo.sh Continuing the example above:

cd exampleProject
../git-svn-mirror/configGitSvnRepo.sh

• Configure the shared git repository as remote of the git svn repository.

git remote add sharedGitRepo [e-mail]:path/to/yourShared/Repository

• Run periodically git-svn-mirror.sh, e.g. as a cron job.

Problems

Different git commit-ids

After merge commits it happens some times, that the git-commit-ids of two git-svn repositories become different. Even if the git-commit-ids of the two repositories were synchron before the merge-commit.

In my expierience, with the following workaround the git-repositories become synchronous again, if applied soon enough:

1. Select the git-svn repository, which became out of sync with the shared repository. And change the working directory into this repository. For excample: cd secondary-repo
2. Force the git-svn branch onto the corresponding commit of the reference repository. For example, if the branch trunk is out of sync: cp .git/refs/remotes/sharedGitRepo/trunk .git/refs/remotes/origin
3. If the current checked out branch is the one, which has got out of sync, reset it to the head of the reference branch, e.g.: git reset sharedGitRepo/trunk
4. Let git-svn update the references: git svn fetch

Tests

Please take a look into the test script TestScripts/fillTestRepro.sh. Running this test script will create the following:

• A test svn repository: ./test-svn-repository
• A git svn repository: ../git-svn-mirror_test_git_svn
• A shared git repository: ../git-svn-mirror_test_git

The test script could give some idea, how to write an own script, to forward changes from a git repository back into the svn repository.