This document shows you how to use Git, just as you
were using SVN in the past. It is to get you
guys up and running with git as soon as possible by
relying on your SVN knowledge and it is focuses on what you want
to do in drools.
document does not really teach
you Git. Git is not just SVN++, it is much more and you should
take some time to learn that too.
SVN trunk is renamed to Git master. A branch is still a
branch. A tag is still a tag.
note: trunk == master
The SVN central repository is now the reference
repository on github, see https://github.com:droolsjbpm/droolsjbpm.
Part 1: Need to know
- you’ve done
the preparation in the dev list mail
- and the correction too, skip to section Getting the source code locally.
- haven’t done the correction yet, do this first
(and the skip to that section):
- Step 4 stated:
- $ git
config --global user.name myUsername // WRONG
- Correct that by running:
- $ git
config --global user.name "My Name"
- $ git
config --global -l
- you haven’t
done the preparation yet, do it now, as stated below.
- 1) Install
git for your OS
- 1a) Linux: Install the package git (and
- $ sudo apt-get install git
- $ sudo apt-get install gitk
- 1b) Windows: Use the icon on the right on http://git-scm.com
- 1c) Mac OSX: Use the icon on the right on http://git-scm.com
- 2) Install
git in your IDE
- 2b) Eclipse: Install the EGit plugin.
- Menu Help, menu item Install new software.
- Work with update site Helios, open Tree item
Collaboration, tree item Eclipse EGit.
- 2c) IntelliJ: Enable the git plugin (if not
- Menu file, menu item Other Settings, menu item
- 3) Get a
Github account: https://github.com/signup/free
- 4) Configure
git correctly (Github also tells you this):
- $ git --version
- git version 1.7.1
- $ git config --global user.name "My Full Name"
- $ git config --global user.email myAccount@gmail.com
- $ git config --global -l
- user.name=Geoffrey De Smet
- 6) Push your
public key to github:
Getting the source code locally
First move your old SVN working directory aside, so
you’re not confused that you shouldn’t work there any more:
$ cd projects
$ mv drools drools-oldsvn
Now you’re ready to get the sources with git. In SVN
this is a svn checkout, but in
Git this is called a git clone. Prefer
the faster, stabler git protocol over the slower https protocol:
$ git clone email@example.com:droolsjbpm/droolsjbpm.git
Next go into that directory
$ cd droolsjbpm
So what’s the command git checkout for? To
switch to another branch, but in the same working directory. In
SVN you also use svn checkout for
note: svn checkout == git clone (new repository) OR git
checkout (change branch)
Follow the instructions in the README.txt to set up
your Eclipse or IntelliJ again.
Getting changes from others
So Mark and Edson changed something in drools-core in
the reference repository. How do I get those changes? In SVN this
is svn update, but in Git
this is a git pull.
$ git pull
note: svn update == git pull
While making your changes, do the same as in SVN: git add, git rm
(instead of svn delete), git status.
note: svn delete = git rm
After making your changes, you ‘ll want to do a git
commit (when you’re done with a changeset) and a git push (to
share those changes with the rest of the team). To recap: doing a
git commit does not push
your changes to the remote repository yet, you also need to do a git push.
$ git commit -m “JBRULES-123 fix testcase”
$ git push
note: svn commit == git commit + git push
Part 2: Tell me more
What is rebasing? A rebase is an
alternative manner of merging: instead of merging your changes
with the incoming changes, it takes the incoming changes and
applies your changes on top of that. For example:
$ git pull --rebase
What is origin?
Because git can work with multiple remote repositories (usually
forks of the same project), the default remote repository is known
as origin. If you’ve cloned the reference
repository, then origin is the
reference repository. If you’ve forked the reference repository as
A and cloned A, then origin is A.
Usually we’ll have 2 types of branches: release
branches and topic branches.
To switch to another branch, just use git
$ git checkout 5.1.x
To create a branch do:
$ git checkout -b 5.2.x
A release branches is copied from the master branch and
only receives bug-fixes. It is separated from the master branch so
no unstable features or improvements (pushed by other developers)
For example: $ git checkout 5.1.x
Cherry picking is very
interesting to pick bug-fixes from the master branch into the
A topic branch is copied from the master branch and is
eventually merged back into the master branch. Its changes are to
disruptive to other team members to be committed to the master
For example: $ git checkout trueModify
Rebasing is very
interesting when you’re working on an experimental feature in a topic branch
for the last few weeks and you want to have the latest changes of
master(=trunk) in there too (= sync up with master):
// on my the myTopic branch
$ git rebase master
After your topic branch is stable, you’ll merge it into
the master branch:
$ git checkout master
$ git merge trueModify
Do you want to really learn
Pro Git book (freely available online): http://progit.org/book/
You’ll easily gain the time you spend reading that
book, because Git is more than SVN++.
Read that book, especially if you’re going to do
branching and merging!
Other references: Hibernate git tricks, SVN
crash course, Git for Gnome developers, ...
With kind regards,
Geoffrey De Smet