Development/Git/Simple Workflow

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Revision as of 19:17, 6 June 2011 by Odysseus (talk | contribs)

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Simple Workflow

This workflow is designed to be as close as possible to the KDE SVN Workflow. It is only recommended to be used for the first few weeks of using Git with KDE while you learn how Git works. Once comfortable with the basic commands you should then move onto the Simple Feature Branch Workflow.


Simple Feature Branch Workflow

This Git Workflow is designed to be followed by a new Git user who needs a simple workflow for bug fixes and new features in a manner similar to the old SVN workflow.

Note that each module may choose to adopt a more complex workflow and you should check with your modules maintainers if this is the case.

The worked examples given will be for an imaginary app called KFoo in a git.kde.org repository called 'kfoo'.

Set-up

This section documents how to set up Git and your code repository for development.

Configure Git

Follow the KDE Git Configuration page.

Clone your repository

You need to copy your repository from git.kde.org into your local KDE source directory. In Git this process is called cloning.

To clone your project repository:

cd your/source/dir
git clone kde:<project>

In our KFoo example:

git clone kde:kfoo

See the KDE Build Environment page for advice on structuring your source directory.

If you have a slow internet connection then you may prefer to download a snapshot tarball to bootstrap your clone. You can copy the required command from the projects.kde.org Repository page for your project, but it will be of the form:

wget -c http://anongit.kde.org/<project>/<project>-latest.tar.gz

Basic Actions

This section documents basic actions that are performed within your workflow.

See also the KDE Git Recipes page.

Create a Work Branch

By default when you first create a repository clone there is only a single local branch called 'master'. It is not good practice to do development in master, it is better kept clean for reference. Instead all work should be performed in a new local branch, even bug fixes.

To see what local branches you have:

git branch

To see all local and remote branches:

git branch -a

To create a new local branch:

git branch <new-branch>
git checkout <new-branch>

This will create a new branch based on whatever local branch you were already in, i.e. that includes all the history of the original branch, which can be useful in building a hierarchy of dependent changes.

You may prefer to base your new branch on a remote branch such as the master branch of the central repository so you can integrate any new development. This is called 'tracking' and is recommended for most branches:

git branch --track <local-branch> <remote-branch>

For our KFoo example:

git branch --track new-bar-feature origin/master

Commit Your Changes

Push Your Changes

Local Feature Development

This example workflow is for locally working on new features in unstable branch and pushing them to the central repository.

This workflow is only recommended for small features or where you are the only developer on a project.

Remote Feature Development

This example workflow is for working on new features in a feature branch hosted on the central repository.

This workflow is recommended for larger features or where there are many developers on a project.

Local Bug Fixing

This example workflow is for locally fixing bugs in both the stable and unstable branches and pushing them to the central repository.

In Git, stable branches are just regular branches that have special meaning to a project and a possibly a special naming scheme to distinguish them. For example, the KFoo app may have the following branches on the central repository:

origin/master
origin/feature/hot-new-stuff
origin/feature/cool-newer-stuff
origin/release/1.0
origin/release/1.1
origin/release/2.0

Making bug fixes to stable branches is thus fundamentally the same as working on a feature branch, but with the added step of needing to push the bug fix to both the stable and unstable branch in the central repository.

Two workflow's are described here, a basic workflow for small apps or where bug-fixes are infrequent, and an advanced workflow for larger apps or more frequent bug-fixes.

Basic Bug Fix Workflow

To make bug fixes on the 2.0 release you could simply checkout a local copy of the origin/release/2.0 branch and make you bug fixes there:

git branch --track bug-fix-2.0 origin/release/2.0
git checkout bug-fix-2.0
<make changes, build, test>
git commit -a
git push origin bug-fix-2.0:release/2.0
git branch --track bug-fix-master origin/master
git checkout bug-fix-master
git cherry-pick -x -e <sha5 of stable commit>
<build, test>
git push origin bug-fix-master:master

Advanced Bug Fix Workflow

the basic workflow works fine except switching between unstable and stable branches inside a single Git repository can lead to large rebuilds if the unstable branch has diverged too much from the stable branch. On a small app this overhead may be small enough to not be a problem, but in most cases this constant rebuilding will be a waste of time.

This workflow uses the [script] to create separate work directories and builds for stable and unstable branches. This depends on you setting different up KDE Environments for the separate builds.