Google Code shut down a year ago, and recently also their “Migrate to Github” feature was disabled.

Because I have/had also a old project hosted (and some people where asking about it recently), I had to find a way on how to migrate the project to Github anyway.

I did these steps

# download the svn dump'ed repo
wget https://storage.googleapis.com/google-code-archive-source/v2/code.google.com/spring-security-facelets-taglib/repo.svndump.gz
# unzip
gunzip repo.svndump.gz
# create the repo
svnadmin create /tmp/testgc
# restore it
svnadmin load /tmp/testgc/ < repo.svndump

# launch a local svn daemon
svnserve --foreground -d

# in another terminal, clone your repo now using git svn (optionally create a authors file for correctly mapping to git usernames)
git svn --stdlayout -A authors.txt clone svn://localhost/tmp/testgc/

# go into the cloned repo
cd testgc/
# add the upstream github repo
git remote add origin https://github.com/domdorn/spring-security-facelets-taglib.git

#push it
git push --set-upstream origin master

#till now, we only have the trunk / master branch
# get atlassians svn-migration-scripts.jar from https://bitbucket.org/atlassian/svn-migration-scripts/downloads
wget https://bitbucket.org/atlassian/svn-migration-scripts/downloads/svn-migration-scripts.jar

# run the scripts and expect the suggested actions
java -Dfile.encoding=utf-8 -jar svn-migration-scripts.jar clean-git

# if you like what you see (usually you do..), perform the actions
java -Dfile.encoding=utf-8 -jar svn-migration-scripts.jar clean-git --force 

# after this i had a branch structure like this:
git branch -a
# * master
#  remotes/origin/0.2_nate
#  remotes/origin/0.4_gblaszczyk
#  remotes/origin/jsf-1.2-spring-2
#  remotes/origin/jsf-1.2-spring-3
#  remotes/origin/jsf-2.0-spring-2
#  remotes/origin/jsf-2.0-spring-3
#  remotes/origin/master
#  remotes/origin/site
#  remotes/origin/site@17
#  remotes/origin/tags/0.1
#  remotes/origin/tags/0.3_jsf-1.2-spring-2
#  remotes/origin/tags/0.3_jsf-1.2-spring-3
#  remotes/origin/tags/0.3_jsf-2.0_spring-2
#  remotes/origin/tags/0.3_jsf-2.0_spring-3
#  remotes/origin/tags/0.5
#  remotes/origin/trunk

# checkout each branch (except tags and trunk) and push it
for i in `git branch -r | grep -v 'tags\|trunk' `; do git checkout ${i/origin\// }; git push;  done

# push the branches
git push --all origin
# checkout each tag and create a tag with the same name

for i in `git branch -r | grep 'tags'`; do git checkout $i; git tag ${i/origin\/tags\// }; done  

# push the tags git push --tags origin 

Thanks to @chrsmith for responding quickly to my google code email (4 minutes, wow!) and telling me about how to download the repo in the svn dump file format.

Thanks to Atlassian for their svn migration scripts

You can see the result of this work at my Spring Security JSF Taglib Github Project.