Git Branching for Success and Profit

Daycamp for developers, this slide deck accompanied my session at the excellent virtual event that is DC4D.

Transcript

1. Git Branching For Success and Profit Lorna Mitchell, Day Camp For Developers
2. Git Branching
3. A Branch is a Label Take a look in .git/refs/heads/ • A branch is a pointer to a commit. • You commit on a branch, the commit is created and the pointer updated.
4. Commits Aren't "On" Branches
5. Commits Aren't "On" Branches
6. 11% of branches never get merged
7. 86% of statistics are made up on the spot
8. Git Branch We are committing along:
9. Git Branch We create a branch and keep committing: git branch feature and git checkout feature git checkout -b feature
10. Git Branch Stuff happens on master meanwhile:
11. Branching is easy. Merging is ?
12. Branching is easy. Merging is easy when you know how.
13. Git Merge
14. Git Merge The plan: • Check out the branch that changes should arrive into. • Merge. git checkout master git merge feature
15. Git Merge
16. Git Undo
17. Git Undo How to undo a merge: • Set the branch pointer back to where it was before the merge git reset --hard 7e386 (your branch is still intact)
18. Git Undo
19. Undo an Old Merge Use git revert but specify which way you want to go at the fork git revert -m 1 d1151
20. Merge Conflicts Merge conflicts occur when git needs some help.
21. DON'T PANIC
22. Merge Conflicts: Your Options • git merge --abort • Edit the files until things are correct • Use git checkout --[ours|theirs] to get the right version in place Fix the conflict, then add and commit the file(s). Your merge will complete
23. Merge Types
24. Fast-Forward Merge No changes on master since we branched
25. Fast-Forward Merge git merge feature
26. Force Recursive Merge Start from the same place:
27. Force Recursive Merge Then merge without fast-forward: git merge --no-ff feature
28. Git Rebase
29. Git Rebase Rebase to move a branch start point
30. Git Rebase git rebase master We can now fast-forward merge
31. Rebase Conflicts Rebase applies each of your commits in turn. This can result in a conflict at any point. Handle exactly as you would for merge conflicts. Then type git rebase --continue. git rebase --abort is always an option.
32. Interactive Rebase Rewrite the last N commits. Your options: • remove a commit completely • re-order commits • combine commits and/or re-word their commit messages
33. Branching Strategies
34. Branching Strategies A branching strategy is basically a git process document. It covers: • when to branch • where to branch from • what to call your branch • where to merge to
35. Git Flow Comprehensive branching strategy, supported by scripts. • Article: http://lrnja.net/1ebawKU • Scripts: https://github.com/nvie/gitflow
36. Git Flow
37. Git Flow
38. Git Flow
39. Git Flow
40. Git Flow
41. Other Branching Strategies • GitHub Flow: http://lrnja.net/1Gr29Jn • Atlassian blog: http://lrnja.net/1BSFQcQ • Docs from GitLab: http://lrnja.net/1AiPxQJ Some common elements can be spotted throughout
42. Branching Strategy Ingredients List
43. Topic Branches Pattern Starting something new? Use a branch.
44. Topic Branches Pattern Merge from master into feature before merging
45. Topic Branches Pattern Rebase branch onto master before merging
46. Master vs Develop This one is a matter of taste!
47. Hotfix Pattern Branch off, commit once, merge with --no-ff • makes it very clear what happened • easily merge the branch back upstream if needed • makes it possible to cleanly undo without losing anything
48. Hotfix Pattern
49. Environment Branches Maintain one branch per platform • branch always reflects current state of platform • plays well with automated deployment
50. Environment Branches
51. Tagging for Releases Git has two types of tags: • simple tags are just a label, like a branch that doesn't advance • annotated tags are an object, they can contain messages git tag -a v2.11 -m "v2.11 with caching" Then push the tag
52. Git Branches
53. Feedback (and Resources) • How was it? https://m.joind.in/talk/50bd3 • Links bundle: http://lrnja.net/135jCIy • My git book: http://gitworkbook.com/ See Also: • Matthew's Scripts: http://lrnja.net/1AiQrgh