An intro to Git and GitHub

Drupal will be soon hosted at GiHub but before that learn Git for your own good and sanity

Panagiotis Papadopoulos6pna / Sfalma@panosjee

DrupalCamp, Athens, 12 December 2010

Who am I?Freelancer and startuper wannabe. Athens Ruby and GTUG organiser.Not a guru in something. Man of all trades master to none with an inclination towards Ruby, Python, Javascript.Do not ask me Drupal, but I will help drupalists with www.sfalma.com (shameless promo)

Subversion is the most pointless project ever started

Linus Torvalds

What is Git?

Git is a distributed revision control system with an emphasis on speed. Git was initially designed and developed by Linus Torvalds for Linux kernel development.

Every Git working directory is a full-fledged repository with complete history and full revision tracking capabilities, not dependent on network access or a central server.

Git's current software maintenance is overseen by Junio Hamano. Git is free software distributed under the terms of the GNU General Public License version 2.

If Git is a heavenly tool, GitHub is a programmer 's heaven.

- PanosJee, December 12th 2010

Source: http://en.wikipedia.org/wiki/Git_(software)

Git is distributed

panosjee jonromero

doxarassavvas

Git is a very simple beast!

Git is:DistributedNon linear developmentEfficient

very small footprintConsists of Git objects which are the actual data of Git, the main thing that the repository is made up of.The four main objects of Git are blobs, trees, commits and tags.

A Git object is a file in the repository compressed (with Zlib) and referenced by the SHA-1 value of its contents plus a small header. The contents of a file are stored as blobs.

The Git model (1)

A simple repo with the following structure:

- module - init.php -- includes - definitions.php -- lib - model.php

Example from the excellent http://peepcode.com/products/git-internals-pdf

Commands$ git init .$ git add .$ git commit -m "first commit"

The Git model (2)

A simple repo with the following structure:

- module - init.php -- includes - definitions.php -- lib - model.php -- validators - email.php

Example from the excellent http://peepcode.com/products/git-internals-pdf

Commands$ git tag "first tag"$ mkdir validators$ touch email.php$ git add .$ git commit -m "added validators"

The Git model (3)A simple repo with the following structure:

- module - init.php -- includes - definitions.php -- lib - model.php * -- validators - email.php

Example from the excellent http://peepcode.com/products/git-internals-pdf

Commands$ vim model.php$ git add .$ git commit -m "include validators"

The Git model (4)A simple repo with the following structure:

- module - init.php -- includes - definitions.php -- lib - model.php -- validators - email.php

Example from the excellent http://peepcode.com/products/git-internals-pdf

Git is snapshot based

1 2

Multiple parents

1

Easy branching

2 3

4

$ git commit -m "new commit"

$ git commit -m "new commit"$ git branch 4

Git is snapshot based

12

1

Easy merging

2 35

master

4$ git merge 4

The virtues of GitFork, Clone, Pull, Remote

Git pull. Full control. Remote repos.

Made for speed, full visibility in a few lines.You can pull from 1-n remote repos. As we said Git is

distributed.

Know thy status

What 's untracked. What 's modified. What 's added. What 's deleted. What 's changed.

Git branches carry their historyOnce you clone a Git repo you have complete access to all previous versions. For ever.

Git stash

Real life scenario.

You are working on your code and your colleagues just pushed a very important fix that you needed.

You cannot pull changes if you have not commited your code, but you should not commit as you are still experimenting.

What do you do ?

Just put your changes aside (git stash) get your friends changes (git pull) and then apply your changes that you had pust aside (git stash apply).

Neat?

Commit to Open Source in a breeze

The distributed nature of Git means you can work locally on code and push to a remote repository when ready.

This is perfect for teams and Open Source projects.

The procedure is simple:1. Find an open source project2. Fork it3. Clone (download locally)4. Do your changes 5. Push to your remote

Wanna have your changes merged into initial repo?

1. Do a pull request2. Hope the author accepts it

$ tools

The best tool you need is to learn the internals of Git you can understand how it works.

The second best tool is the command line. Master it. You will never look back.

Git integrates with various IDEs like Eclipse, NetBeans.

There are also great standalone Git apps.

“The bad workman blames his tools” American Proverb“We shape our tools and afterwards our tools shape us.” Marshall McLuhan

Tower - Mac App - Still beta - Impressive

GitX for Mac - GitK for other platforms

GitWeb - Web UI - Shipped with Git

Giggle - Linux

GitHub is the Facebook of Code

GitHub is an unparallel tool that offers you unlimited public repos and private repos on subscriptions plans.

Github is:1. Collaboration tool2. Code host3. Wiki4. Issue tracker5. Code review tool6. Git UI7. Social

I am always struck by the wealth of project I find on GitHub. Lots of major open source projects are there for you to use and study.Fork them, change them, contribute in no time.

If you are a coder and you have never used GitHub you probably live in a parallel universe :P

GitHub Network Graph Viewer

Questions?You may also use Mercurial, Fossil, Bazaar but

Mercurial and Git are the winners :P

http://bit.ly/git-dcath