intro to git: a hands-on workshop

Introduction to GitAshley Roach -- API Architect – DevNet

Twitter: @aroach

Email: asroach@cisco.com

• Introduction

• Quick overview of Git

• Workshop

• Resources

Agenda

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• 3 Levels of Prizes at 2, 5 and 10 activities

• Have the InfoDesk Staffer check off your prize collection in the app!

WHY ARE WE HERE?

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As si618 said on Stack Overflow“Have you ever:

• Made a change to code, realised it was a mistake and wanted to revert back?

• Lost code or had a backup that was too old?

• Had to maintain multiple versions of a product?

• Wanted to see the difference between two (or more) versions of your code?

• Wanted to prove that a particular change broke or fixed a piece of code?

• Wanted to review the history of some code?

• Wanted to submit a change to someone else's code?

• Wanted to share your code, or let other people work on your code?

• Wanted to see how much work is being done, and where, when and by whom?

• Wanted to experiment with a new feature without interfering with working code?

In these cases, and no doubt others, a version control system should make your life easier.”

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http://stackoverflow.com/a/1408464

DISTRIBUTED VERSION CONTROL

• Opens up to new workflows: git flow

• Each system has an exact replica of the repo as other collaborators.

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https://git-scm.com/images/about/workflow-b@2x.png

Under the hood

• Changes are stored in trees

• Trees contain changed files

• Commits contain trees

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http://git-scm.com/figures/18333fig0903-tn.png

GIT CONFIG

• So you can be held accountable, configure git

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$ git config --global user.name "Your Name Comes Here"

$ git config --global user.email you@yourdomain.example.com

GIT INIT

• Initializes a project directory with a hidden directory /.git/

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$ tar xzf project.tar.gz

$ cd project

$ git init

GIT ADD

• Add any files in your repository to git “stage”

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$ git add .

https://git-scm.com/images/about/index1@2x.png

GIT COMMIT

• Store your changes into a commit

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$ git commit –m ’Initial commit’

BRANCHING: Your safe place

• Makes a pointer to your code

• Moves HEAD around

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http://git-scm.com/figures/18333fig0307-tn.png

$ git branch <name>

$ git branch testing

$ git commit –m “new”

$ git checkout master

MERGING

• git merge <topic>

• You must be on the branch you want to merge INTO when you execute this command (e.g. master)

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$ git merge <topic>

Git over SSH vs HTTP

• No password

• Set up SSH key on remote server

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$ git clone git@github.com:aroach/upgraded-guacamole.git

$ git clone https://github.com/aroach/upgraded-guacamole.git

SHARE YOUR CHANGES

• git push <destination> <branch>

• git push origin master

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$ git push <destination> <branch>

$ git push origin master

Workshop

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Let’s get started

• http://bit.ly/git-berlin

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Additional Resources

• https://training.github.com/kit/downloads/github-git-cheat-sheet.pdf

• https://www.atlassian.com/git/tutorials/comparing-workflows/

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Contact

• Ashley Roach

• asroach@cisco.com

• @aroach

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CLEUR DevNet Zone Story

Thank you