GIT SCM

Contents

• Popularity– Projects that use/require Git

• Functionality– Distributed repository– Branching/merging

• Learning• Resources required• Support by 3rd party tools• Summary

Git vs SVN on Google Trends

GitHub vs SourceForge on Google Trends

Projects that use Git

• Linux kernel• Ruby on Rails• jQuery• node.js• Twitter bootstrap• Diaspora SN• Symfony (requires it!)• Facebook OS projects

• less.js• Elastic search• Eclipse• Gnome• KDE• Qt• Android (!!!)• Stanford/Berkley in

their learning courses

Git Concepts

• Local Repository(just type git init, or right click…)

• Commit• Push/pull• Origin ( the place you took the source from)• Tags ( real tags, no space required, made

effortlessly)• Branches (actual branches, not copies of code)

Distributed vs Centralized

But, you can use Git as a centralized repository as well

Can have local

branches

Team branches(feature,

release, maintenance)

Pros• Git is incredibly faster than SVN cause nearly all operations other

than push and pull work locally• Uses compression when storing/sending code over network. As a

result pull/clone/push happen a lot faster.• Preserves the actual author of the code during merge• Allows simultaneous storage of several branches in a single folder• Allows offline commits• Branches know where they came from. Merging them is a piece of

cake• Does not pollute your repo by creating stupid .svn folders in each

folder

Pros continued• Git repos are much smaller than SVN’s (30x smaller in

case of Mozilla project)• Git branches are simpler and less resource heavy than

SVN's• Git allows you to execute hooks on some events(commit,

push, pull)• Allows commit amend (fix your last commit)• Requires the damned comment thing• To be sure that you won’t loose some code you can just

commit it locally instead of copying the files• Ignoring files is easier

What people will learn when working with git

• A more modern way to do SCM• They will learn to actually do branching. It won’t be

a pain in the ass• They would be forced to type in the damned

comment when committing. The thing’s important.• They won’t have to learn it anyway when they

finally encounter it in the wild (symfony2)• Anyone who knows git can handle SVN anytime• Contributing

Cons

• Steep learning curve• Some UI tools do not yet fully support Git• Is harder to configure on client machine ( at

least it was a year ago )• It is impossible to checkout a portion of the

project tree (???)• Cumbersome revision numbers

Git performance

Git Branching?

• Tracks the project revision the branch started from• Records branch merge events (author, time, date,

branch revision info)• Changes made on the branches remain attributed

to original authors• Changes made during the merging process are

attributed to the merging user• Automatically starts the next merge at the last

merge (a branch can be merged twice)

Possible Branching Model

Resources RequiredSVN Git

• Centralized server• Client software• TortoiseSVN• IDE/plugin• Command line

SVN client

• Centralized server• Client software• TortoiseGit• IDE/plugin• Command line git

client• SmartGit if none

of the above suits

Setup on windows

• mysysgit port of git to windows• Public/private certificates on each user

machine for auth• TortoiseGit (so one will have lovely icons on git

managed folders)• SmartGit looks like the best UI tool (I haven’t

tried eclipse built-in git plugin)

Tools

• TortoiseGit• Command line utility• SmartGit• Eclipse git plugin ( EGit )• Git source control provider for Visual Studio

Resources

• A successful Git branching model http://goo.gl/b1EA7

• Good Git cheatsheet http://goo.gl/vUSlV• Git website http://goo.gl/D3sxy