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
possibleby relying on your SVN knowledge and it is focuses on what you
want to do in drools.
This document does not reallyteach 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.
Translation note: trunk == master
The SVN central repository is now the referencerepository on github, see
Part 1: Need to know
* you’ve done the preparation in the dev list mail
o and the correction too, skip to section Getting the source
o 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
o 1a) Linux: Install the package git (and optionally gitk)
+ $ sudo apt-get install git
+ $ sudo apt-get install gitk
o 1b) Windows: Use the icon on the right
o 1c) Mac OSX: Use the icon on the right onhttp://git-scm.com
+ Optionally install gitx fromhttp://gitx.frim.nl/
* 2) Install git in your IDE
o 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.
o 2c) IntelliJ: Enable the git plugin (if not enabled):
+ Menu file, menu item Other Settings, menu item
* 3) Get a Github
* 4 <https://github.com/signup/free
>) Configure git correctly
(Github also tells you this):
o $ git --version
o git version 1.7.1
o $ git config --global user.name "My Full Name"
o $ git config --global user.email myAccount(a)gmail.com
o $ git config --global -l
o user.name=Geoffrey De Smet
* 6) Push your public key to github:
o Follow the instructions
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 firstname.lastname@example.org:droolsjbpm/droolsjbpm.git droolsjbpm
Next go into that directory
$ cd droolsjbpm
So what’s the command git checkoutfor? To switch to another branch, but
in the same working directory. In SVN you also use svn checkoutfor that.
Translation 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
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
Translation 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.
Translation 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 commitdoes 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
Translation note: svn commit == git commit + git push
Part 2: Tell me more
What is rebasing? A rebaseis 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
originis the reference repository. If you’ve forked the reference
repository as A and cloned A, then originis A.
Usually we’ll have 2 types of branches: release branches and topic branches.
To switch to another branch, just use git checkout:
$ 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) leak in.
For example: $ git checkout 5.1.x
Cherry pickingis very interesting to pick bug-fixes from the master
branch into the release branch.
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 immediately.
For example: $ git checkout trueModify
Rebasingis very interesting when you’re working on an experimental
feature in a topicbranch 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 reallylearn Git?
Read the 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 <http://git-scm.com/course/svn.html>
;, Git for Gnome
With kind regards,
Geoffrey De Smet