Version Control & Git

Geoff Ford & Craig Smith

Suncorp

According to Wikipedia:

“… is the management of changes to documents, programs, and other information stored as computer files.”

Image: http://i.ehow.com/images/GlobalPhoto/Articles/2065416/dictionary_Full.jpg

Before Version Control

File renamingCode.001CodeNov1.xml

Directories\Nov1Code

Zip filesNov1Code.zip

Nothing at all Image: http://www.stud.u-szeged.hu/Sajben.Emma/TW1128-Rock-Stars.jpg

We have moved on…

haven’t we?

Image http://yabadabadoo.files.wordpress.com/2008/03/puzzled-fred.jpg

•diff

•SCCS1970’s

•RVS

•CVS1980’s Tool

Support1990’s

DVCS (Bitkeeper,Git, etc…)

2000’s

A Brief History

Image http://www.free-background-wallpaper.com/images/Wallpapers1280/Beach-Wallpaper/Sand-Dunes-Soft.jpg

Version Control is…

Backup & restore

Synchronisation

Undo

Track changes

Sandbox / spike

Branch / merge

Not just for code

Image http://globalnerdy.com/wordpress/wp-content/uploads/2007/10/version_control_star_trek_style.jpg

Check-in&

Check-out

Branching&

Merging

SubversionSetup

Image http://blog.daemon.com.au/images/SourceImage/svnstructure.jpg

Version Control Best Practice

Use good comments

Commit often

Single vs multi project repos

Branch/tag when appropriate

Binaries/large files

Respect the trunk

Get to know your command line & client

Image http://www.improvizations.com/Portals/42614/images//best-

practice%20checklist-resized-600.jpg

• d

Visualisation: FishEye/SVNStat

Traditonal / Centralised

Version Control

Distributed Version Control

Hybrid Model

Version Control

Why Distributed Version Control?

Cheap local branches for easy experimenting

History aware merges

Full local history

Offline commits

Each working copy is a complete backup of the repository

Example DistributedVersion Control

Tools

Git (2005)http://git-scm.com

Mercurial (2005)http://mercurial.selenic.com

Bazaar (2005)http://bazaar-vcs.org

Darcs (2004)http://darcs.net

Git is Fast

Git is Efficient

git clone git://example.com/repo.git

Clone

Git Workflow

git checkout -b new-feature

Working Branch

git add .

git commit -m “Commit Message”

Commit

git rebase master

git checkout master

git merge new-feature

Rebase & Merge

git push origin

Push

git svn clone http://example.com/repo

Clone

Git + SVN Workflow

git checkout -b new-feature

Working Branch

git add .

git commit -m “Commit Message”

Commit

git rebase master

git checkout master

git merge new-feature

Rebase & Merge

git dcommit

Push to SVN

Repository Many Branches

Many Branches + Merges

LiveDemo

Want More Information?Geoff Fordgeoff.ford@suncorp.com.au

Craig Smithcraig.smith@suncorp.com.au

References:

http://www.spearce.org/2007/07/difficult-gitk-graphs.html

http://www.infoq.com/articles/dvcs-guide http://ldn.linuxfoundation.org/article/dvcs-round-one-

system-rule-them-all-part-3 http://gaveen.owain.org/2008/05/simple-diagram-on-

distributed-vcs-hint.html http://betterexplained.com/articles/a-visual-guide-to-

version-control/ http://en.wikipedia.org/wiki/Revision_control