STEFAN SAASEN • STASH DEVELOPMENT MANAGER • ATLASS IAN • @stefansaasen

True GitTHE GREAT MIGRATION

TODO Show of hands

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Add attribution slide

Source Control Management

2011 2013 (projected) 2013 2015 (projected)

68

4941

20

55

706878

SVN Git

Why am I passionate about this?

Why Git?

Branching & Mergingfast, cheap and simple

first class concept

Branching & Mergingfast, cheap and simple

first class concept

Foundation for new workflows

Speed

git bisect

git log

git diffgit status

Bad

Good (v2.7) TestRegression!

Fast graph traversalFast checkout

git bisect

Enables new features

Improves basic featuresSpeed

git bisect

git log

git diffgit status

Local commitsRewrite History

Edit & Publish

FlexibilityLocal commitsRewrite History

Edit & Publish

Git does what you are doing today, only better

LABEL T ITLE

GIT

SVN

New ways of collaborating

Existing workflows

New branchworkflows

LABEL T ITLE

GIT

SVN

New ways of collaborating

Existing workflows

New branchworkflows

Release branching master

2.8

2.7

Bugfix

Git Workflows a-la-carte

N i c o l a P a o l u c c i

Rapid Agile Delivery

M a t t h e w W a t s o nT h u r s d a y - 1 1 : 1 5 a m T h u r s d a y - 1 : 1 5 p m

So you’ve decided to migrate!

The process

1

2

3

Inception

Adoption

Conversion

• 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

Inception 1

1

1

2

3

The process

Inception

Adoption

Conversion

• 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

Adoption 2

2

Just text by itself, for impact.

2

1

2

3

The process

Inception

Adoption

Conversion

We’ve got you covered!

&Scripts Tutorial & Documentation

bit.ly/go-dvcs

git-svn

3

jdeveloper = John Developer <jd@example.com>

Map Authors

Identify SVN repository layout

/tags/trunk/branches

3Conversion - Preparation

git svn clone \ --authors-file=/authors.txt \ --trunk=/trunk \ --tags=/tags \ --branches=/branches

3Conversion - Initial Clone

?

git svn fetch

3Conversion - Sync

Infrastructure first 3

CI Issues IDE

read-only

Sync every minute

• Cleanup branches

• Remove unused files

• Create git tags

• Remove commit metadata

3Conversion - Cleanup

Then your team 3

CI Issues IDE

read-only read-only

Other Tools?SubGit

1

2

3

The process

Inception

Adoption

Conversion

Or are you?

Just text by itself, for impact.

Collaboration model?Branching model?

Centralized=+

Enterprise

Builds

Metrics

Issues

Deployments

Workflows will changefor the better

but they don’t have to change on day one!

This happened in both Confluence and JIRA...

master

confluence-project-4.0

CONF-1234

git cherry-pick bae6251

From SVN like

master

confluence-project-4.1

CONF-2345

git merge confluence-project-4.1git merge confluence-project-4.1

To git branch based workflow

Contributions from outside of the team

Sub-Teams

Forks can be useful!

Conclusion

0

20

40

60

80

2011 2013 (projected) 2013 2015 (projected)

68

4941

20

55

706878

SVN Git

Subversion (58%) is being

threatened by Git (47%) for de facto leadership of the Version Control space. ZEROTURNAROUND DEVELOPER PRODUCTIVITY REPORT 2013

”

“

is here to stay

expands

migration is a solved problem

Thank you!

STEFAN SAASEN • STASH DEVELOPMENT MANAGER • ATLASS IAN • @stefansaasen