SVN / Git

1. Re-establishing a git svn clone on a separate machine

I wanted to clone my existing SVN repository, https://code.google.com/p/svntime/, into a new Git repository https://github.com/soundasleep/svntime.

Based on Using Git with Subversion and Importing from Subversion.

Note that this means that all revisions and issues will all appear to come from the same user. Setting up SVN/Git synchronisation to support multiple users with correct authentication requires a lot of extra architecture and work and security for storing passwords.

0. Create a map of SVN authors to Git authors

This will let Github blame your commits properly with the -A flag. For example svn-authors.txt:

soundasleep@gmail.com = Jevon Wright <jevon@jevon.org>
soundasleep = Jevon Wright <jevon@jevon.org>
(no author) = Google Code <code@google.com>

1. Clone remote SVN into local Git

1. Execute git svn clone -s https://svntime.googlecode.com/svn/ svntime -A svn-authors.txt --prefix=origin/ (NOT the /trunk dir! The -s flag assumes /trunk.)

You can also do subdirectories within the repository for subprojects without the -s flag, e.g. git svn clone https://svntime.googlecode.com/svn/trunk/sub-project/ sub-project -A svn-authors.txt.

2. Push local Git into remote Git

1. Create a new empty Git repository on Github
2. Add the remote origin source: git remote add origin https://github.com/soundasleep/svntime.git
3. Push the SVN commits to Git: git push origin master

This will create individual commits for each SVN revision.

3. Make a local change, commit to both Git and SVN

1. Modify a file.
2. Commit it to local Git: git add -A && git commit
3. Push it to remote Git: git push
4. Commit it to remote SVN: git svn dcommit
5. Setup the remote Git as the remote origin: git branch --set-upstream-to=origin/master master

4. Merge remote SVN changes into local Git

1. Update the local Git from remote SVN: git svn rebase -A ../svn-authors.txt (each revision will appear as a new commit)
2. Push to remote Git: git push

5. Merge remote Git changes into SVN

1. Pull from remote Git into local Git: git pull
2. Update the local Git from remote SVN: git svn rebase -A ../svn-authors.txt
3. Commit changes to remote SVN: git svn dcommit (each commit will appear as a new revision)

If you correctly set up the author map list, then your Github will correctly recognise old commits.

6. Merge a Pull Request

1. For example, https://github.com/soundasleep/openclerk/pull/1
2. Follow the Github command line instructions to checkout the pull request branch as a separate remote branch
3. Execute git rebase to rebase this branch to the latest master - you'll probably have to git mergetool a lot, since the branch will have no knowledge of master's commits
4. git push and git svn dcommit as usual

Unable to extract revision information from commit

If you get this during a git svn dcommit, then you've probably messed up the merge somewhere - you need to git rebase before you merge changes between branches.

git svn rebase: Unknown option: strategy-option

Good luck. I think this is a bug.

ignore-paths not matching files

It turns out the regexp accepted by --ignore-paths is not a complete regexp; it needs an anchor (^ or $) in order to match. So instead of doing something like --ignore-paths=".+custom.css", you need to do --ignore-paths="custom.css$".