1. Francesco Pira | fpira.com
First steps with Git
Francesco Pira
fpira.com
@pirafrank
me@fpira.com
Linux Day 2016 - Enna (Sicily)

2. Francesco Pira | fpira.com
Who am I?
• Web developer
• btw currently sys admin
• I like Python
• I’ve founded a startup (no much fuss...)
• I write a blog in my spare time
• ...and some code (github.com/pirafrank)
• I like business
• ...but code is better!

3. Francesco Pira | fpira.com
What is a VCS?
• VCS stands for Version Control System
• A software to handle different versions of a pool of files
• Great to manage source code
• Something you need to get a job
• Something you need to share your weekend project
• Something you need to deploy and maintain your blog
• See Github Pages, GitLab Pages and Jekyll

4. Francesco Pira | fpira.com
Why VCS?
• A repository as a unique codebase
• Reliability
• History and changes + easy to roll back at any point
• Blaming (who changed what?)
• Side projects (aka forking a repo)
• Parallel development on the same repo (aka team working)
• Code deployment!

5. Francesco Pira | fpira.com
Popular VCS software
● Git
● Team Foundation Server (MS)
● Apache Subversion (SVN)
● Mercurial (BitBucket)
● Bazaar (Canonical)
* In order of popularity

6. Francesco Pira | fpira.com
• repository = a directory with files (usually code!)
• working tree = index of files part of the repo
• ignoring = no to keep track of changes
• staging = virtual area with changes ready to commit
• commit = snapshot of a repository, changes saved in history
• head = pointer to the latest commit of the current branch
• branch = a copy of files to track different changes
• merging = merging the history of a branch with his parent one
• conflict = 2 or more people making changes to same file
• tag = named pointer to a particular snapshot (e.g. v1.1.0)
• remote = server (it can be another PC for distributed VCS)
VCS concepts

7. Francesco Pira | fpira.com
Who’s Git?
• Created by Linus Torvalds (mid 2005)
• to manage the shared development of Linux kernel
• Today is the most common VCS
• It works using snapshots, pointers and compressed deltas
• All changes and history are in ./.git
• Works best with small files (see git lfs)
• Distribute (remote) architecture
• Used by GitHub: the biggest and de facto standard platform
for sharing open-source code

8. Francesco Pira | fpira.com
Setup the environment
● Download and install git
○ bit.ly/linux-day-git-install
● Set it up
○ git config --global user.name "My Name"
○ git config --global user.email "my@email.com"
● Remotes require your to have an RSA key: set it up!
○ ssh-keygen -t rsa -b 4096 -C "my@email.com"
○ eval "$(ssh-agent -s)"
○ ssh-add ~/.ssh/id_rsa
Pro tip: Use different RSA keys (personal, work, etc.)

9. Francesco Pira | fpira.com
Your first commit, yay!
Locally on your computer
• git init
• git add .
• git remote add origin ...
• git commit -m “Hey! This is my first commit”
• git push origin master
Your teammate
• git clone ...

10. Francesco Pira | fpira.com
Some notes
master is the main and first branch
origin is the primary remote. You push your code to it
Tip: Use --global to make a setting work for all repo of current
local user
Interesting: Git global configuration usually lives here
~/.gitconfig or here ~/.config/git/config

11. Francesco Pira | fpira.com
Live demo

12. Francesco Pira | fpira.com
• init = initialise the repository (make ./.git subdir)
• clone = make a local copy of the repo from a remote one
• diff = show current changes (before staging them)
• add = stage one of more file / folders
• commit = make a ‘snapshot’ / save a state
• branch = create a branch off the current one
• merge = merge a branch into his parent
• fetch = download (new) changes from remote
• pull = fetch from remote branch + merge to local one
• checkout = switch branch / restore file in working tree
• reset = undo / remove from staging area
• log = explore changes history
• … tons of commands, each one has tons of parameters: RTFM!
Main Git commands

13. Francesco Pira | fpira.com
Lazy as a pig? Aliases!
git config --global alias.co checkout
git config --global alias.br branch
git config --global alias.ci commit
git config --global alias.st 'status -s'
git config --global alias.unstage 'reset HEAD --'
...Make yours!

14. Francesco Pira | fpira.com
Best practices
• Don’t zip repositories! Use remotes!
• master as the main branch
• devel as the main development branch
• all features start off devel
• all features ends
• usually you don’t push features
• all releases must be tagged (in master)
• use semantic versioning for tags
• hotfix start off master, merged to master and devel

15. Francesco Pira | fpira.com
Credits to Vincent Driessen

16. Francesco Pira | fpira.com
Live demo

17. Francesco Pira | fpira.com
UI clients
● Windows and macOS
○ Sourcetree
● Linux
○ SmartGit

18. Francesco Pira | fpira.com
Best platforms
● GitHub
○ Free only for open-source public projects
● BitBucket
○ Free for unlimited private or public repos (any license)
○ Paid for 5+ collaborators
● GitLab
○ Paid enterprise version (with support)
○ Free Community Edition (self-hosted)
○ Free gitlab.com: unlimited repos, unlimited collaborators

19. Francesco Pira | fpira.com
Your turn!
• Wow! git log --graph --oneline --decorate --all
• Discover git stash and git pop
• Deploy best practices
• Use git-flow
• Deploy a web application using git
• Try git-lfs
• ...Have fun!

20. Francesco Pira | fpira.com
Sources and extras
• https://git-scm.com/book/en/v2/Getting-Started-Git-Basics
• https://help.github.com/articles/generating-a-new-ssh-key-and-addi
ng-it-to-the-ssh-agent/
• https://www.atlassian.com/git/tutorials
• http://nvie.com/posts/a-successful-git-branching-model/
• http://semver.org (semantic versioning)

21. Francesco Pira | fpira.com
Thank you!
Keep in touch
fpira.com
@pirafrank
me@fpira.com
github.com/ pirafrank