The document discusses migrating from Subversion (SVN) to Git version control. It outlines a three step process: 1) inception to determine suitability and test conversion; 2) adoption to get team buy-in; 3) conversion including preparing metadata, initially cloning the SVN repository, syncing changes, and cleaning up the Git repository. The document emphasizes getting infrastructure like continuous integration and issue tracking ready first before converting developer workflows. It also notes that while workflows may change over time, they do not need to change immediately upon conversion.

2. True Git
THE GREAT MIGRATION
STEFAN SAASEN
•
STASH DEVELOPMENT MANAGER
•
ATLASSIAN
•
@stefansaasen

3. TODO Show of hands
Picture with hands/lighter/concert
Add attribution slide

4. Source Control Management
78
70
68
68
49
41
55
20
2011
2013 (projected)
SVN
2013
Git
2015 (projected)

5. Why am I passionate about this?

6. Why Git?

7. first class concept
Branching & Merging
fast, cheap and simple

8. first class concept
Foundation for new
Branching & Merging
workflows
fast, cheap and simple

9. git bisect
Speed
git log
git status
git diff

10. Good (v2.7)
git bisect
Regression!
Test
Fast graph traversal
Fast checkout
Bad

11. git bisect
Enables new features
Speed
Improves basic features
git log
git status
git diff

12. Edit & Publish
Local commits
Rewrite History

13. Edit & Publish
Local commits
Flexibility
Rewrite History

14. Git does what you are
doing today, only better

15. GIT
SVN
LABEL TITLE
Existing
workflows
New branch
workflows
New ways of
collaborating

16. GIT
SVN
LABEL TITLE
Existing
workflows
New branch
workflows
New ways of
collaborating

17. Release branching
master
2.8
2.7
Bugfix
!

18. Git Workflows
a-la-carte
Rapid Agile
Delivery
Nicola Paolucci
Thursday - 11:15 am
Matthew Watson
Thursday - 1:15 pm

20. So you’ve decided to
migrate!

21. The process
Adoption
2
1
3
Inception
Conversion

22. Inception
• Is git suitable?
• Test the conversion
• Identify the repositories that need to be
converted
• Identify the tools that need to be updated. CI,
issue tracking, IDE, scripts and build tools,
deployment tools
1

23. 1

24. The process
Adoption
2
1
3
Inception
Conversion

25. Adoption
2
• You need to answer: “What’s in it for me”
• Make sure tooling is ready and can be used by
everyone
• Identify the git champions - they will be thrilled
to help
• Don’t expect to win everyone over immediately

26. 2

27. 2
Just text by itself, for
impact.

28. The process
Adoption
2
1
3
Inception
Conversion

29. We’ve got you covered!
&
Scripts
Tutorial & Documentation
bit.ly/go-dvcs

30. 3
git-svn

31. Conversion - Preparation
3
Map Authors
jdeveloper = John Developer <jd@example.com>
/tags
/trunk
/branches
Identify SVN
repository layout

32. Conversion - Initial Clone
?
3
git svn clone
--authors-file=/authors.txt
--trunk=/trunk
--tags=/tags
--branches=/branches

33. Conversion - Sync
git svn fetch
3

34. Infrastructure first
read-only
Sync every minute
CI
Issues
IDE
3

35. Conversion - Cleanup
• Cleanup branches
• Remove unused files
• Create git tags
• Remove commit
metadata
3

36. 3
Then your team
read-only
CI
Issues
read-only
IDE

37. SubGit
Other Tools?

38. The process
Adoption
2
1
3
Inception
Conversion

39. Or are you?

40. Collaboration model?
Branching model?
Just text by itself, for
impact.

41. Metrics
Issues
Builds
Deployments
+
Enterprise
= Centralized

42. for the better
Workflows will change
but they don’t have to change on day one!

43. This happened in both
Confluence and JIRA...

44. From SVN like
git cherry-pick bae6251
confluence-project-4.0
CONF-1234
master

45. To git branch based workflow
git merge confluence-project-4.1
git merge confluence-project-4.1
confluence-project-4.1
CONF-2345
master

46. Forks can be
useful!
Contributions from
outside of the team
Sub-Teams

47. Conclusion

48. 80
78
70
68
60
20
0
49
41
40
68
55
20
2011
2013 (projected)
SVN
2013
Git
2015 (projected)

49. “
Subversion (58%) is being
threatened by Git (47%) for de
facto leadership of the Version
Control space.
”
ZEROTURNAROUND DEVELOPER PRODUCTIVITY REPORT 2013

50. is here to stay

51. expands

52. migration is a
solved problem

53. Thank you!
STEFAN SAASEN
•
STASH DEVELOPMENT MANAGER
•
ATLASSIAN
•
@stefansaasen