Git & GitHub & Open Source (Clermont'ech Workshop Git)

In this talk, you will learn how to use Git and GitHub in an efficient manner, but also how to manage Open Source projects, and what it actually means.

Online slides: http://slides.williamdurand.fr/git-and-github-and-open-source/
Sources: https://github.com/willdurand-slides/git-and-github-and-open-source

Transcript

1. Git & GitHub & Open Source
   William Durand ‑ November 15th, 2014
   

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2. Open Source
   

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3. In production and development, Open Source as a
   development model promotes a universal access via a
   free license to a product's design or blueprint [...].
   http://en.wikipedia.org/wiki/Open_source
   

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4. Open‑source software is very often developed
   in a public, collaborative manner.
   

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5. ® GitHub
   

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7. GitHub is the largest code host on the planet
   with over 17.1 million repositories.
   

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8. Integrated Issue Tracking
   

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9. Integrated Issue Tracking
   

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10. Syntax Highlighting
    

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11. Collaborative Code Review
    

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12. Collaborative Code Review
    

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13. Pull Request = Code + Issue + Code Comments
    

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14. GitHub Pages
    

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15. Release Management
    

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16. Compare View
    

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17. GitHub Tip #1
    

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18. t File Finder
    

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19. How To Contribute?
    

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20. Everyone can contribute.
    

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21. Fork The Repository
    

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22. Create A Branch
    git checkout -b feature-branch
    

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23. Eat, Sleep, Code, Repeat.
    

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24. Submit A Pull Request
    But, how?
    

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25. Look At The
    CONTRIBUTING
    File
    (If it does not exist, contribute by adding it!)
    

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26. Write Good Commit Messages
    Capitalized, short (50 chars or less) summary
    More detailed explanatory text, if necessary. Wrap it to about 72
    characters or so. In some contexts, the first line is treated as the
    subject of an email and the rest of the text as the body. The blank
    line separating the summary from the body is critical (unless you omit
    the body entirely); tools like rebase can get confused if you run the
    two together.
    Write your commit message in the imperative: "Fix bug" and not "Fixed bug"
    or "Fixes bug." This convention matches up with commit messages generated
    by commands like git merge and git revert.
    Further paragraphs come after blank lines.
    Å A Note About Git Commit Messages
    

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27. Rebase Your Branch
    

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28. Squash Your Commits
    git rebase -i HEAD~2
    pick 5335450 add test
    pick 4c20f8d Fix undefined variable
    # Rebase 35124cb..4c20f8d onto 35124cb
    #
    # Commands:
    # p, pick = use commit
    # r, reword = use commit, but edit the commit message
    # e, edit = use commit, but stop for amending
    # s, squash = use commit, but meld into previous commit
    # f, fixup = like "squash", but discard this commit's log message
    # x, exec = run command (the rest of the line) using shell
    #
    # These lines can be re-ordered; they are executed from top to bottom.
    #
    # If you remove a line here THAT COMMIT WILL BE LOST.
    #
    # However, if you remove everything, the rebase will be aborted.
    #
    # Note that empty commits are commented out
    Å Squashing commits with rebase
    

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29. Push & Create
    

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30. Profit!
    

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31. What Happens Then?
    

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32. An Open Source maintainer will look at your work.
    

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33. Pull Request Review
    Understand the goal of the PR
    Try to reproduce the issue
    Try the fix
    Test the new feature
    Think about edge cases
    Write documentation if not provided
    

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34. Dealing With Releases
    

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35. Semantic Versioning
    MAJOR.MINOR.PATCH
    Å semver.org
    

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36. Changelog
    A change log is a file which contains a curated, ordered
    list of notable changes for each version of a project.
    Å keepachangelog.com
    

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37. Release Process
    1. Run test suite(s)
    2. Update documentation, changelog, version
    3. git commit -m "Prepare X.Y.Z release"
    4. git tag vX.Y.Z
    5. Build artifact (gem build, etc.)
    6. Update version number (Z++)
    7. git commit -m "Bump version to X.Y.Z+1-dev"
    8. git push origin master --tags
    9. Publish artifact (gem push, etc.)
    10. Publish a GitHub release
    

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38. hub
    git + hub = github
    alias git=hub
    

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39. Clone
    git clone random/repo
    # git clone git://github.com/random/repo.git
    git clone repo
    # git clone git://github.com/YOUR/repo.git
    

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40. Browse
    git browse
    # open https://github.com/random/repo
    git browse -- issues
    # open https://github.com/random/repo/issues
    

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41. Easy Fetch
    git fetch ubermuda
    # git remote add ubermuda git://github.com/ubermuda/repo.git
    # git fetch ubermuda
    

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42. Checkout
    git checkout https://github.com/your/repo/pull/123
    # git remote add contributor git://github.com/contributor/repo.git
    # git fetch contributor
    # git checkout -b contributor-branch contributor/branch
    Best way to [work on|review|test] a Pull Request so far!
    

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43. Apply Commits
    git am -3 https://github.com/your/repo/pull/123
    

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44. Cherry‑Pick
    git cherry-pick https://github.com/random/repo/commit/SHA
    # git remote random git://github.com/random/repo.git
    # git fetch random
    # git cherry-pick SHA
    

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45. More!
    git fork, git pull-request, merge, ci-status, etc.
    Å hub.github.com
    

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46. Dealing With
    PATCH & DIFF
    

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47. Creating A Patch
    git format-patch master --stdout > fix-undefined-variable.patch
    From: William Durand
    Date: Thu, 13 Nov 2014 10:22:17 +0100
    Subject: [PATCH] Fix undefined variable
    ---
    test.js | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)
    diff --git a/test.js b/test.js
    index 760e4eb..60ac996 100644
    --- a/test.js
    +++ b/test.js
    @@ -1,5 +1,5 @@
    (function () {
    - var i;
    + var i, j;
    i = 0;
    j = i;
    --
    2.1.2
    

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48. Changes Overview
    git apply --stat fix-undefined-variable.patch
    test.js | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)
    

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49. Test The Patch
    git apply --check fix-undefined-variable.patch
    No output == ›
    

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50. Then, Apply
    git am --signoff < fix-undefined-variable.patch
    Applying: Fix undefined variable
    commit 4c20f8d517b99638f5379f3f0894ad076d2b6a5b
    Author: William Durand
    Date: Thu Nov 13 10:22:17 2014 +0100
    Fix undefined variable
    Signed-off-by: William Durand
    BTW, patch -p1 works too!
    

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51. GitHub Tip #2
    

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52. .patch
    https://github.com/your/repo/commit/e0af340837978f80d8cd144a4475.patch
    

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53. Applying A Commit As A Patch
    curl https://github.com/your/repo/commit/.patch |git am
    Applying: Fix undefined variable
    

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54. .diff
    https://github.com/your/repo/commit/e0af340837978f80d8cd144a4475.diff
    

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55. Dealing With
    Everything Else
    

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56. Fixing The Code Is Not Enough
    

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57. Full‑Time Hobby
    

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58. Just do it.
    

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59. Provide Support
    

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60. ... Everywhere
    

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61. Create Things That People
    Actually Use (& Like)
    

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62. Inspire Others
    

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63. Makes People Feel Good
    

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64. Receive Overwhelming Feedback
    

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65. ... & Gifts
    

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66. Thank You.
    Questions?
    ¾
    ®
    ¬
    williamdurand.fr
    github.com/willdurand
    twitter.com/couac
    

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67. Bonus: (My) Useful
    Git Commands
    

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68. Atomic Commits
    git add -p
    diff --git a/test.js b/test.js
    index 60ac996..2a57310 100644
    --- a/test.js
    +++ b/test.js
    @@ -1,6 +1,5 @@
    (function () {
    - var i, j;
    + var i = 0, j;
    - i = 0;
    - j = i;
    + j = 1;
    })();
    Stage this hunk [y,n,q,a,d,/,s,e,?]? s
    Split into 2 hunks.
    @@ -1,3 +1,3 @@
    (function () {
    - var i, j;
    + var i = 0, j;
    Stage this hunk [y,n,q,a,d,/,j,J,g,e,?]?
    

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69. Amending A Commit
    git commit --amend -m 'Fix undefined variable j
    Fix #123'
    

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70. Fast Pull & Rebase
    git pull --rebase origin master
    

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71. Go Back
    git checkout -
    Switched to branch 'master'
    git checkout -
    Switched to branch 'feat-undefined-variable'
    

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72. (Un)Merged Branch
    git branch --no-merged
    develop
    feat-another-feature
    feat-my-feature
    fix-undefined-variable
    git branch --merged
    * master
    

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73. Links
    http://williamdurand.fr/2013/11/20/on‑creating‑pull‑requests/
    http://gitready.com/advanced/2009/02/10/squashing‑commits‑with‑rebase.html
    http://git‑scm.com/book/en/v2/Git‑Branching‑Rebasing
    http://tbaggery.com/2008/04/19/a‑note‑about‑git‑commit‑messages.html
    

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