How to get involved with an open source project using github. Shows the process of forking and cloning, a bit of a git primer, and how to submit pull requests. Also how to approach and contribute to an open source project.

1. Git, Github and Open Source

2. About Me
• Lorna Jane Mitchell
• Consultant, author, speaker
• Github: http://github.com/lornajane
• Twitter: @lornajane
• Web: http://lornajane.net
• Project lead of joind.in, open source project
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3. Github
"We make it easier to collaborate with others and share your projects with
the universe"
• Github is a hosted source control solution, based on git.
• Used by open source projects, personal projects
• Paid-for offerings for non-public code
There are other ways to do git, open source, and probably everything
mentioned here ...
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4. Centralised Version Control
The overall ecosystem with git looks different because instead of this:
repo
checkout checkout checkout
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5. Distributed Version Control
Things look like this:
repo
repo repo repo repo
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6. Distributed Version Control
Or rather:
repo
repo
repo
repo
repo
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7. Code on GitHub

8. Get a Repo
• Find the project
• Fork the project
• Clone your repo
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9. Fork the Project
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10. Clone your Repo
git clone git@github.com:username/joindin.git
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11. Git: Many Repos
GitHub
joindin/joind.in
fork
your-user/joind.in
clone
development
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12. Working with Git

13. Git Overview
A few key commands you will need:
• git log and git show
• git status and git diff
• git add
• git commit
• git pull and git push
• reverting changes
Then we’ll talk about branching
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14. Git Log
Git automatically sends the output to a pager like less
commit 76916fed387d9161d48b0f1e592685c183e4757c
Author: Lorna Mitchell <lorna@lornajane.net>
Date: Wed Mar 14 21:06:24 2012 +0000
adding the actual announcement wording to the banner
commit 3fdc9f6b9795ed6a3a02465817bfebb8f77ca34e
Author: Kim Rowan <rowan02@unknown-00-25-00-44-3a-04.home>
Date: Tue Mar 13 12:58:48 2012 +0000
Added info block to main page announcing php|arch Impact Award nom
commit dc5777199aa2bb822b498ec1dea99f3e89ee90e0
Author: Lorna Mitchell <lorna@lornajane.net>
Date: Sun Mar 11 21:03:13 2012 +0000
removed some unused files
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15. Git Log
There are some alternative views, this is git log -graph -oneline
* 76916fe adding the actual announcement wording to the banner
* 3fdc9f6 Added info block to main page announcing php|arch Impact Awa
* dc57771 removed some unused files
* aa502ec straightening out a problem with API metadata not showing up
* 6719b8a GH #473: Refactored ternary to if
* d6a69d7 Merge branch 'joindin-167'
|
| * b7effc5 JOINDIN-167: Facebook users without username (this is poss
* | 6af9450 JOINDIN-167: reverted removal of facebook login
* | 6249401 Merge branch 'master' of https://github.com/joindin/join
|
| |/
|/|
| * 16b31d3 Merge remote-tracking branch 'lornajane/no-facebook'
| |
| | * 36ee9ea removing facebook login functionality - hopefully tempor
| * | f4a2a73 removing references to the gravatar cache; these are ser
| |/
| * 83d6c04 Prevented forwarding on to anywhere except this site after
| * d411358 Merge remote-tracking branch 'mvriel/JOINDIN-161_2'
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16. Git Status
Shows you what you have changed, and what will be in your next commit
(these are two different things)
After editing a couple of files:
# On branch impact-banner
# Changes not staged for commit:
# (use "git add <file>..." to update what will be committed)
# (use "git checkout -- <file>..." to discard changes in working dir
#
# modified: src/.htaccess
# modified: src/system/application/views/main/index.php
#
no changes added to commit (use "git add" and/or "git commit -a")
To include changes in a commit, we need to stage them first using
monogit add
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17. Git Add
git add src/system/application/views/main/index.php
git status again
# On branch impact-banner
# Changes to be committed:
# (use "git reset HEAD <file>..." to unstage)
#
# modified: src/system/application/views/main/index.php
#
# Changes not staged for commit:
# (use "git add <file>..." to update what will be committed)
# (use "git checkout -- <file>..." to discard changes in working dir
#
# modified: src/.htaccess
#
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18. Git Commit
git commit -m ’meaningful commit message’
• Without the -m, git will open your default text editor to add a message
• You can also supply a list of files to include in the commit
• Use git add -interactive to stage sections of files
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19. Undoing Changes
To undo changes that you haven’t staged yet:
git checkout -- path/to/file
If you have staged the changes, you can still undo them:
git reset
git reset --hard
Reset will unstage the changes; the hard reset puts everything back to the
most recent commit
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20. Managing the Multiple Repositories

21. Stay in Sync
Pull the changes from upstream into your local repo
GitHub
changes upstream
your-user/joind.in pull
development
git pull upstream master
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22. Stay in Sync
The changes are now in your local repo, push them to github:
GitHub
changes upstream
your-user/joind.in
push
changes locally
git push 22

23. Branching in Git
What you need to know:
• Branching (and merging!) are fast and painless
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24. Branching in Git
What you need to know:
• Branching (and merging!) are fast and painless
• Branches are private by default
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25. Branching in Git
What you need to know:
• Branching (and merging!) are fast and painless
• Branches are private by default
• Branches are in the repo, they are not copies
• no updating vhosts
• only one directory with code in
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26. Git Branching Commands
Create a new branch:
git checkout -b new-branch-name
Switch to an existing branch
git checkout branchname
List branches in this repo
git branch
Branches are local by default, they don’t synchronise to other repositories
unless asked
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27. Best Practice in Branching
Git doesn’t dictate a process, so usually each project does. Common
features:
• Branch for features
• Branch for fixes
• Branch for experiments
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28. Best Practice in Branching
Git doesn’t dictate a process, so usually each project does. Common
features:
• Branch for features
• Branch for fixes
• Branch for experiments
• Basically: branch!
By keeping changes in branches, they are very easy to merge to another
repo or branch
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29. Sharing Changes
Your changes are in your local branch - how do they get into a main
project?
GitHub
joindin/joind.in
your-user/joind.in
local feature
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30. Sharing Changes
git push origin new-branch-name
GitHub
joindin/joind.in
feature at origin
push
local feature
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31. Sharing Changes
To offer changes upstream, make a pull request
GitHub
joindin/joind.in
pull request
feature at origin
local feature
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32. Making a Pull Request
Make the pull request on GitHub
Explain what you have changed, and why. Keep changes atomic.
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33. Open Source Contributions
After that:
• Your pull request appears on the project’s list
• http://github.com/joindin/joind.in/pulls
• Hopefully it gets merged
• You get bragging rights :)
• https://github.com/joindin/joind.in/contributors
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34. Where to Begin with Open Source
How to get involved: (warning, contains bias!)
• Check for introductory docs
• http://joind.in/about
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35. Where to Begin with Open Source
How to get involved: (warning, contains bias!)
• Check for introductory docs
• http://joind.in/about
• Get code and set up the project
• usually, fork the repo and read the README
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36. Where to Begin with Open Source
How to get involved: (warning, contains bias!)
• Check for introductory docs
• http://joind.in/about
• Get code and set up the project
• usually, fork the repo and read the README
• Find the bug tracker, and pick something
• http://joindin.jira.com
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37. Where to Begin with Open Source
How to get involved: (warning, contains bias!)
• Check for introductory docs
• http://joind.in/about
• Get code and set up the project
• usually, fork the repo and read the README
• Find the bug tracker, and pick something
• http://joindin.jira.com
• Talk to the other people in the project
• #joind.in on freenode
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38. Where to Begin with Open Source
How to get involved: (warning, contains bias!)
• Check for introductory docs
• http://joind.in/about
• Get code and set up the project
• usually, fork the repo and read the README
• Find the bug tracker, and pick something
• http://joindin.jira.com
• Talk to the other people in the project
• #joind.in on freenode
• Share and enjoy
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39. Questions?

40. Thanks!
• Slides will be on slideshare
• Github: http://github.com/lornajane
• Twitter: @lornajane
• Web: http://lornajane.net
PHPNW - 3rd April, Derick Rethans on MongoDB. Rain Bar, Manchester.
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