Getting Started/Sources/Amarok Git Tutorial: Difference between revisions

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= Getting started with git  =
Depending on whether you simply want to test and follow Amarok development, write the occasional patch, or are an Amarok developer, the steps to use the repo are different.


== Follow and test the latest development code  ==
Amarok is now developed in a Git repository instead of SVN. This was done to help get into place all the needed infrastructure to convert all of KDE, including documentation. <br>


git clone git://gitorious.org/amarok/amarok.git
[https://community.kde.org/Amarok/Development/Git Amarok/Development/Git] contains the most up-to-date information on Amarok related git topics. [https://community.kde.org/Infrastructure/Git KDE Git page] also provides more details.


This creates an 'amarok' directory. cd into that and use it like normal. And when you want to update:  
=== Basic Development  ===
 
90% of the time this is all that is needed:  


  git pull --rebase
  git pull --rebase
#hack, compile, build. It works!
git status #to check if you want to commit all the modified files
git commit -a
git log
git push


will download the new changes.
''git pull --rebase'' downloads the latest changes. The --rebase option takes any unpushed local commits and applies them to the latest code, moving it to the top of the history. It is the equivalent of ''git pull; git rebase origin/master''. See the "1. Rebase" section of [http://magazine.redhat.com/2008/05/02/shipping-quality-code-with-git/ Shipping Quality Code] for a good explanation of what rebase does.
:If you have uncommited changes you can not rebase. Instead you can ''git stash'', do the rebase, and then ''git stash apply''.


== Patch Contributors ==
''git status'' will tell you what files are modified. If you created a new file, use ''git add'' on it to "track" it. If there are some junk files, you can add a regexp to .gitignore in the root.  
You can use the method above, make your changes, then do 'git diff' to create a patch like normal. Or you could use the following rules to create your own fork of Amarok with the additions you would like to request to merge. This makes it easier for Amarok Developers to track your changes and is better for more complicated patches.


*Make sure you have created your account on Gitorious and are logged in. Go to the project you want to clone (e.g. Amarok - http://gitorious.org/amarok) and select the branch which you want to clone (in this case Amarok - Mainline which is the master branch).
''git commit -a'' will commit all unmodified files. You can use ''git add'' and then simply ''git commit'' instead if you wish to commit only certain files.
*After selecting the branch you can click "Clone this repository on Gitorious". Give your branch a name and you'll be taken to the page of your newly created clone. On this page you find two git urls: one to publicly clone the repository and the "Push url: git@gitorious.org:~yourname/amarok/yourname-clone.git.
*Clone the push url to start working on your clone:
git clone [email protected]:~yourname/amarok/yourname-clone.git
...work on this checkout - follow the normal development workflow...
push your changes to gitorious
*You can follow the main development branch easily by adding it as remote branch:
git remote add upstream git@gitorious.org:amarok/amarok.git
*Update by pulling from the remote:
git pull upstream master
*To submit your patches: Create a merge request on gitorious by going to your clone page and selecting "Request merge" in the menu on the right. Alternatively you could email [email protected] with your branch public branch URL and ask that it be merged. (We just started this, so exactly how to do such things still hasn't been decided).
*Remember to use one branch per feature/bug fix!


== Amarok Developers  ==
Use ''git log'' to review the local unpushed commits. Possibly also useful is ''git diff origin/master'', which will give you a diff between the current checkout and what is in the central repo.


=== gitorious.org account setup ===
''git push'' pushes all the local commits to the central repo.


*Create an account on [http://gitorious.org gitorious.org] the git hosting service used by Qt and now Amarok.  
= Follow remote feature branch =
*On your user page, (that's at http://gitorious.org/~your_nick) click on "Manage SSH keys" and add your SSH key.
With git, feature branches are cheap and easy. Here's how to follow a feature branch someone else has already setup.


People with KDE-SVN accounts als should do the following:  
Remember that you can't push to git:// URL's when picking what URL to use.


*Again from the user page, click on "Manage aliases" and add any email addresses you've ever used in KDE SVN. This way any commits you've made in the past are tracked back to you. If your gitorious email address is the only one you ever used, then this step isn't needed.  
git remote add jeff git://git.kde.org/clones/amarok.git/mitchell/pudaction.git
*Request one of the kde-developers admins to add your username to the group (the same rules apply as KDE SVN account requests). This will give you push rights to Amarok. Lydia, Ian and Jeff are all admins.
git remote update
git branch -a
git branch jeff-pud jeff/pudaction-removal
git checkout jeff-pud
#and later you want to switch back to the mainline
git checkout master


=== Setup Amarok Clone ===
''git remote add'' adds a new remote named 'jeff' with the given URL. Think of remotes like bookmarks: you could always just explicitly pull from a URL instead.


Gitorious has one address for cloning, and another for pushing. The pushing address can be used for cloning, so the easy thing to do is just use that.  
''git remote update'' downloads all the remotes you have without merging them, including the remote you just defined. This is a handy command if you're tracking multiple remotes.


git clone git@gitorious.org:amarok/amarok.git
''git branch -a'' this lists all the branches you have, including the remote branches. Find the new branch you want to look at.


This will create a directory 'amarok'. cd into that and start developing!
''git branch'' this command creates a local branch called 'jeff-pud' that tracks the remote branch 'pud-action/pudaction-removal'. You figured out the name of the latter in the previous command.


=== Basic Development ===
''git checkout'' is how you switch between branches.
 
90% of the time this is all that is needed:
 
git pull --rebase #update to latest code and apply your local commits on top.
(you can still use git pull for some cases).
#edit code, build, it works!
git status #to check if you want to commit all the modified files
git commit -a #the -a option commits all modified files. use git add to select them individually
git push


There's a some of problems with this:
Recommended reading  =
#git commit -a doesn't catch added or removed files.
#git push will fail if anyone else has pushed
#If git pull is not a fast-forward update, it will create a merge commit which may or may not be what you want. Then it's recommended to use git pull '''--rebase''' to rebase your work on top of the recent changes. It avoid to have history full of merge that are useless.


If it doesn't work '''read more documentation'''.
*[http://tom.preston-werner.com/2009/05/19/the-git-parable.html The Git Parable] ''Background information that will help you understand git and distributed revision control systems in general''
*[http://git.or.cz/course/svn.html Git to SVN crash course] ''5 minute introduction to git for experienced SVN users''
*[http://www.redhatmagazine.com/2008/05/02/shipping-quality-code-with-git/ Shipping Quality Code with Git] ''Guide to cleanup before a push''
*[http://eagain.net/articles/git-for-computer-scientists/ Git for Computer Scientists] ''Quick introduction to git internals for people who are not scared by words like Directed Acyclic Graph.''
*[http://www.youtube.com/watch?v=4XpnKHJAok8 Linus Torvalds on Git] ''Why git? answered by the man that started it.''  
*[http://gitready.com/ Git Ready!] ''Learn git one commit at a time''
*[http://book.git-scm.com Git Community Book] ''An online book covering git from the basics to some advanced features''
*[http://www-cs-students.stanford.edu/~blynn/gitmagic Git Magic] ''Covers some concepts and common usage patterns''
*[http://ktown.kde.org/~zrusin/git/git-cheat-sheet.svg Zack Rusin's git cheat sheet]
*[http://cheat.errtheblog.com/s/git Git cheat sheet] ''Yet another git cheat sheet''
*[http://sysmonblog.co.uk/misc/git_by_example git by example] ''git command reference and explanation''  
*[http://jonas.nitro.dk/git/quick-reference.html Git Quick Reference] ''Yet another reference of the most used git commands''


= Recommended reading =
= Todo for this doc =


[http://tom.preston-werner.com/2009/05/19/the-git-parable.html The Git Parable:] ''Background information that will help you understand git and distributed revision control systems in general''<br> [http://git.or.cz/course/svn.html Git to SVN crash course] ''5 minute introduction to git for experienced SVN users''<br />
*creating feature branches
[http://www.redhatmagazine.com/2008/05/02/shipping-quality-code-with-git/ Shipping Quality Code with Git] ''Guide to cleanup before a push''<br />
*history manipulation. rebase -i, commit --append, and what to do when things go wrong. Probably its own page.
[http://eagain.net/articles/git-for-computer-scientists/ Git for Computer Scientists] ''Quick introduction to git internals for people who are not scared by words like Directed Acyclic Graph.''<br />
[http://www.youtube.com/watch?v=4XpnKHJAok8 Linus Torvalds on Git] ''Why git? answered by the man that started it.''

Latest revision as of 12:32, 1 June 2024

Amarok is now developed in a Git repository instead of SVN. This was done to help get into place all the needed infrastructure to convert all of KDE, including documentation.

Amarok/Development/Git contains the most up-to-date information on Amarok related git topics. KDE Git page also provides more details.

Basic Development

90% of the time this is all that is needed:

git pull --rebase
#hack, compile, build. It works!
git status #to check if you want to commit all the modified files
git commit -a
git log
git push

git pull --rebase downloads the latest changes. The --rebase option takes any unpushed local commits and applies them to the latest code, moving it to the top of the history. It is the equivalent of git pull; git rebase origin/master. See the "1. Rebase" section of Shipping Quality Code for a good explanation of what rebase does.

If you have uncommited changes you can not rebase. Instead you can git stash, do the rebase, and then git stash apply.

git status will tell you what files are modified. If you created a new file, use git add on it to "track" it. If there are some junk files, you can add a regexp to .gitignore in the root.

git commit -a will commit all unmodified files. You can use git add and then simply git commit instead if you wish to commit only certain files.

Use git log to review the local unpushed commits. Possibly also useful is git diff origin/master, which will give you a diff between the current checkout and what is in the central repo.

git push pushes all the local commits to the central repo.

Follow remote feature branch

With git, feature branches are cheap and easy. Here's how to follow a feature branch someone else has already setup.

Remember that you can't push to git:// URL's when picking what URL to use.

git remote add jeff git://git.kde.org/clones/amarok.git/mitchell/pudaction.git
git remote update
git branch -a
git branch jeff-pud jeff/pudaction-removal
git checkout jeff-pud
#and later you want to switch back to the mainline
git checkout master

git remote add adds a new remote named 'jeff' with the given URL. Think of remotes like bookmarks: you could always just explicitly pull from a URL instead.

git remote update downloads all the remotes you have without merging them, including the remote you just defined. This is a handy command if you're tracking multiple remotes.

git branch -a this lists all the branches you have, including the remote branches. Find the new branch you want to look at.

git branch this command creates a local branch called 'jeff-pud' that tracks the remote branch 'pud-action/pudaction-removal'. You figured out the name of the latter in the previous command.

git checkout is how you switch between branches.

Recommended reading  =

Todo for this doc

  • creating feature branches
  • history manipulation. rebase -i, commit --append, and what to do when things go wrong. Probably its own page.