Options for replacing CVS for Horde Development
Decision
** We have decided to keep the current history and structure in CVS, and create a new Git repository. Code will be committed to the Git repository as it is cleaned up for PHP 5 and Horde 4. **
Introduction to distributed version control systems
- http://betterexplained.com/articles/intro-to-distributed-version-control-illustrated/
- http://www.infoq.com/articles/dvcs-guide
Description
This project is to determine what the next generation of the Horde will use to store and organize source code.
Some initial work has been done with Git and SVN conversions of the current CVS repository.
Requirements
Must-haves
- Offline review of local changes
- Ability to hook into Whups for ticket updates from commit messages
- Stable, mature codebase
- Functional, usable user interface
Nice-to-haves
- Submodule support
Today checking out a Horde app within an existing Horde checkout works fine. This includes making single-commit changes across applications.
- Browseable by Chora
Naturally no matter what we choose Chora support will either be added or will improve. However if it is already supported by Chora all the better.
The Contenders
In alphabetical order...
Bazaar
Bazaar from Canonical (i.e. the ubuntu company)
- http://bazaar-vcs.org/
Advantages
- Seems to preserve the most metadata per-commit of any SCM listed here
Disadvantages
- Somewhat specific to Launchpad/Ubuntu development process
Well-known users
- Canonical/Ubuntu
Git
http://git.or.cz/
http://www.opensolaris.org/os/community/tools/scm/git-report-final.txt
http://www.gitcasts.com/git-talk
Setup
#!/usr/bin/env sh
cd /var/www/git/horde/
export CVSROOT=":pserver:cvsread@anoncvs.horde.org:/repository"
FILES="agora
ansel
chora
whups
wicked"
for FILE in $FILES
do
echo $FILE": "
git-cvsimport -C$FILE $FILE
done
Submodules
I added a git submodule for every horde module inside the horde/horde
git clone git://git.koch.ro/git/horde/horde
cd horde
git submodule init
foreach modules as MODULE // Only those you want to use
git submodule update $MODULE // checks out the module
Now there are some more things[1] to think about when actually developing, but
ls -C -w60
agora goops jonah nag swoosh
ansel groupware juno nic trean
chora hermes klutz occam turba
CVSROOT horde kronolith passwd ulaform
dimp hordedoc luxor pearweb update.sh
forwards hordeweb merk presentations vacation
framework imp midas sam vilma
genie incubator mimp scry volos
gitgc.sh ingo mnemo sesha whups
gollem jeta mottle skeleton wicked
/var/www/git/horde$ du -hs
928M
Advantages
- Distributed nature allows offline commits and easy branching
Disadvantages
- Does not preserve history across file or directory renames
- Aimed at large-scale codebases with emphasis on features for those users (ie. Linux Kernel)
Well-known users
- Linux Kernel
Mercurial
Alternative distributed versioning control system.
Advantages
- Distributed nature allows offline commits and easy branching
Disadvantages
- Toolset possibly less mature than other products
Well-known users
- OpenSolaris
Subversion
- Chuck Hagenbuch has done some work on writing svn post-commit hooks. These likely can be reused for other SCM systems as well.
- Ben Klang has dome some test conversions of the CVS repository to SVN. The repository size is indeed much larger. In addition submodule support (as we use it today) has not been proven to the satisfaction of the developers.
Well-known users
- Asterisk
- KDE
Previous discussion re: migrating Horde to SVN: http://bugs.horde.org/ticket/5284
People
While all Horde developers are interested in this project's final recommendation the following people have done work toward making a decision on the next SCM to be used for Horde:
- Ben Klang
- Chuck Hagenbuch
Resource Utilization Comparison
Ingo