1. Version Control with Git and GitHub

2. Lets look at the course website

3. Why use version control?
Enables collaboration
Merge changes to the same file
View how code changes over time
Visualize history of a code file
Revert to specific version
Recent change breaking things? Undo!
See who is contributing
Find all changes by username
Backup
Master copy is kept elsewhere (hopefully)
Great for solo projects too!

4. Basics of Version Control

5. Basics of Version Control
Each user has a working copy
Changes must get committed to the server
Might require a merge

6. Types of Version Control
Older VCS were “centralized”
CVS
SVN
Distributed version control!
Git
Mercurial
with GitHub for hosting and services

7. Distributed Version Control

8. GitHub-User Perspective
You
GitHub
Working Dir
Local Repos
Remote Repos

9. First: Lets set up Git git config --global user.name “Austin Henley”
git config --global user.
git clone
git config credential.helper store
git pull
Warning: stores pw in plaintext locally
Alternative: setup Git to use SSH

10. Optional: If you don’t like VI
If VS Code is installed and in your PATH
Test by doing: code –help
git config --global core.editor “code --wait”
git config --global -e

11. Try it!

12. Working with Git working directory staging area gets repo from GitHub
local repository
clone
remote repository

13. Working with Git working directory add stages files you changed
staging area
local repository
remote repository

14. Working with Git working directory staging area commit saves changes
local repository
remote repository

15. Working with Git working directory sends all your commits to GitHub
staging area
local repository
push
remote repository

16. Working with Git working directory staging area
gets latest version from GitHub
local repository
pull
remote repository

17. Handy commands Get the repo for the first time
git clone
See the status of your local repo
git status
Stage a file you modified
git add filename
Stage all modified files
git add -A
Commit staged changes
git commit -m ”Foobar”
Push your commits to GitHub
git push

18. Try it!

19. Get previous versions See commits to a file
git log filename
Get previous version of repo
git checkout commitid .
Get previous version of file
git checkout commitid -- filename
Go back specific number of commits (e.g., 5)
Git checkout master~5 -- filename
Return to latest version
git checkout master

20. I made a mistake! How do I…
Unstage a file?
git reset HEAD filename
Uncommit?
git reset --soft HEAD^
Undo your changes and go back to a fresh repo?
git reset --hard HEAD^
Careful!!!

21. How to organize a commit?
Commits should be logical groupings of code changes
E.g., all the changes to fix a bug
Try to make commits small and frequent
Not fun to look through 2000 lines of changes across 11 files 

22. A Few Resources A tutorial A visual explanation of Git
A visual explanation of Git
Git cheat sheet for commands

23. Lets walk through GitHub