This document discusses the benefits of distributed version control systems (DVCS) like Git over centralized version control systems (CVCS) like SVN. It argues that DVCS tools make collaboration and branching much easier and more flexible. Various workflow models for DVCS are presented, including integrating feature branches and using different roles like integration managers. The document provides references for learning more about Git and distributed version control.

1. Embracing Distributed Version Control How to Drastically Improve Collaboration, Experimentation, Productivity, Freedom, Flexibility, Data Integrity and take two strokes off of your golf game

2. Lets Talk About It Open Forum Ask questions Ask for demonstrations Add opinions Share experiences Try it yourself

3. What's the Big Deal? Tools should mold to your process Projects have lots of independent features Feature isolation "Major Milestone" vs. "Release Often" "Only commit when its done" is limiting

4. The Basics

5. Centralized Version Control Systems One centralized server with the revision database single point of failure Clients checkout a working copy to their machine Most operations happen on the server Checkouts/Updates happen one directory at a time Linear revision history (merges squash commits) Every directory contains a "special folder"

6. Distributed Version Control Systems Every client has a full revision history locally # backups == # clients no need to be online All operations are local (except sharing) Non-linear revision history Network operations are compressed into packed downloads Working copy is independent of versioning system

7. Different to the Core

8. How Did We Get Here Again?

9. There Can Only Be One... or maybe two Everyone has their own opinions In the end choose what system fits best but whatever you do, choose a DVCS (at least for your local development) Today we will compare SVN and GIT

10. Lets Take a Walk... Side by Side SVN GIT Obtain Code svn checkout <url> git clone <url> Add Files svn add file1.php *.css git add file1.php *.css Status svn status git status Differences svn diff | less git diff Restore File svn revert <path> git checkout <path> Commit All Changes svn commit git commit -a Get Latest Updates svn update git pull Share Latest Edits git push

11. Branching

12. I've Branched Before... So What? With CVCS branching is used to separate major releases Branching is always followed by merging Both tasks need to be easy and inexpensive

13. Branching is Hard... Or is it? Tasks Obtain the source code Create Branch Switch Branch Merge Branch

14. Branching is Hard... Or is it? REPO=http://svn.php.net/repository/php/php-src/ svn checkout $REPO/trunk (10 minutes) svn copy $REPO/branches/PHP_5_3 $REPO/branches/PHP_5_5 (4 minutes) svn switch $REPO/branches/PHP_5_5 (50 seconds) svn merge -r 20:HEAD $REPO/branches/PHP_5_3 (claw your eyes out) Total Time: ~15 minutes + clawing your eyes out Total Time Branching: ~5 minutes

15. Branching is Hard... Or is it? git clone git://github.com/php/php-src.git (3 minutes) git branch PHP_5_5 origin/PHP_5_3 (5 milliseconds) git checkout PHP_5_5 (2 seconds) git merge origin/PHP_5_3 (1 second) Total Time: ~3 minutes Total Time Branching: ~3 seconds

16. OK. So Branching Is Easy... Now What? Cheap and easy branching fundamentally changes the way you approach development Everything is done on a branch Issue isolation is now a reality

17. Every Change Has Its Place in a Branch You can use any branching style you choose. Here's an example: master also referred to as trunk hotfix-X quick fixes to master develop integration point for all completed feature branches feature-Y every discreet issue is worked on in a feature branch complete walk-through: http://nvie.com/git-model

19. Workflow

20. Your Centralized Workflow With Centralized Version Control Systems, your workflow will always look like this. image source: http://whygitisbetterthanx.com

21. Chose Your Own Adventure Workflow With Distributed Version Control Systems you can morph your workflow to meet your needs. You can do it the same... image source: http://whygitisbetterthanx.com

22. Or It Can Work Like This... Integration Manager Approach Useful for small to large teams Integration manager merges all feature branches into mainline

23. Or It Can Work Like This... Dictator and Lieutenants Useful for large teams Team Leaders curate new feature branches into production ready state Dictator has final say and merged into mainline

24. Migration & Integration

25. Dipping Your Toes in the Water Use your favorite DVCS with most other VCS repositories Push and Pull changes between systems

26. Diving in Head First Import entire history/branches from legacy systems Rinse & repeat: make you have everything before you switch

27. References GIT http://git-scm.com/course/svn.html http://whygitisbetterthanx.com/ http://nvie.com/git-model/ http://progit.org/book/ http://gitref.org/ http://gitready.com/ Mercurial http://hginit.com/

28. Get In Touch Nowell Strite Twitter: nowells Email: nowell@strite.org Matthew Weier O'Phinney Twitter: weierophinney Email: matthew@weierophinney.net