Session Plan

Session materials

These are some examples of previously created materials by mentors that you can use yourself, or for inspiration.

Introduction to Git (by @aina21, Team 31)
Git Basics
Git Branches

Session outline

What is version control?
- Version control is like a super-organized notebook that keeps a history of all the changes made to your project folders and files. It lets you:
  - Go back to older versions if something goes wrong
  - See who made each change
  - Work with others without overwriting each other’s work
- Google docs demonstration
Git - the most popular version control system
- Git is a version control system, widely used by software developers (and not only). Think of it as a smart time machine for your files—especially code or text documents.
  - Save a snapshot of your project (called a commit) at any point
  - Compare changes between versions
  - Work together with other people and combine everyone’s work smoothly
  - Experiment with new ideas safely, without messing up the main project
Git vs. GitHub (Slide 3 from Git-basics.pdf)
- Git
  - Version control software on your computer
  - Works offline (no need for internet)
  - Command-Line Interface based, but has various graphical interface alternatives as GitHub Desktop, GitKraken, SourceTree
- GitHub
  - Website that hosts Git repositories in the cloud
  - Web interface for viewing code and changes
  - Collaboration tools (pull requests, projects, issues, comments)
  - Enabled social coding (followers, stars, forks, use profiles)
Install Git if not done already
Configure Git
- git config --global user.name "name"
- git config --global user.email "email"
- git config --global core.editor "code -w" (without -w the commit is aborted with empty message)
Command line basics
- pwd, and explain how paths work
- ls
- cd
- cd ..
- mkdir
- do a little exercise
What is a repository and how to create one (Slide 4, Git-basics.pdf)
- kind of a folder, but not all files in the folder have to be in the repository
- git init
- Clone an existing repository
Golden rule:
- ALWAYS make sure you are not inside a git repository when you create a new one. You can check by typing git status in your Terminal. If you get an error it means you are not inside a git repository and you can safely create a new one.
The commit (Slide 7, Git-basics.pdf)
- a snapshot of the entire repository
- who made the changes
- when the changes were made
- a message describing the changes in the commit
Demonstration to making a commit
- what happens after each git add and git commit
- show how to git add all changes, or specific files
- show git status and git log
Explain what happens after git push
Branches (Exercise 2, Git-branches.pdf)
1. Create a branch
2. Make a commit
3. push changes to remote
Pull Requests
1. Create a pull request
2. Reviewing a pull request (commenting, approving, requesting changes)
3. Merging a pull request
4. Updating local main
Forks
- Your "copy" of a source repository
- How forks are useful for collaboration
Useful VS Code extensions
- GitLens - Git supercharged
- GitHub Pull Requests

Exercise 1

Objective: The goal is to set up your assignment repository fork and create your first PR (Pull Request).

[!NOTE] You will use this repository to hand in your assignments during the entire HackYourFuture program.

Create a repository fork on your GitHub and clone it locally, following the instructions from HackYourFuture-CPH/hyf-assignment-template
Check out to a new branch called html-and-css
Add the session exercises from the previous week to the html-css/week1 folder
Create a PR (Pull Request) to your own repository, from your html-and-css branch to merge changes into the main branch
Finally, have the person on your right review this PR before you agree to merge it to main.

Tips for this exercise:

Use descriptive commit messages
Make a commit for each folder/exercise you add (makes it easier to track changes/updates)
Switch between the Terminal and GitHub on each commit and push to learn better what each command exactly does
Merge, after the person on your right has reviewed and approved. You might need to first address any comments they might have.

Exercise 2

When you are on main branch, of the assignment repository create a branch named git-week1/exercise-1/<your-name> and move to it
Create a folder named session-playground in the git folder, under /week1
Create the following files inside the session-playground folder: apples-file.txt, bananas-file.txt, oranges-file.txt
Add some text to each of the files
Add and commit the apples-file.txt
Add and commit both the oranges-file.txt and the bananas-file.txt
Add more text to the apples-file.txt
Add and commit the changes in the apples-file.txt
Push your changes to GitHub
Go to the branch on GitHub and look at the commits, analyze and discuss how it looks and how it connects with what you just did

Exercise 3

Objective: The goal of this exercise is to practice the assignment workflow.

When you are on main branch, create a branch named git-week1/exercise-3/<your-name> and move to it
Create a file named my-assignment.txt in the git folder, under /week1/session-playground
Add some text to the my-assignment.txt file
Add and commit the changes in the my-assignment.txt file
Add more text to the my-assignment.txt file
Add and commit the changes in the my-assignment.txt file
Push your changes to GitHub
On GitHub, create a pull request (on your own fork) from the exercise branch to main
On your computer add some more text to the my-assignment.txt file
On your computer, add and commit the changes in the my-assignment.txt file
Push the changes to GitHub
On GitHub, check what happened to the pull request you created in step 8.
Merge the pull request.
Locally, go to the main branch and update main by "downloading" the new commits from GitHub: git pull origin main.

Exercise 4

Objective: Face your first Git error and try to find a solution online on your own.

On your assignment repository go to the branch main, create a branch git-week1/exercise-4/<your-name> and move to it
In the git folder, under /week1/session-playground, create a file named colors.txt
Add two colors to the file colors.txt, one per line
Add and commit the changes in the colors.txt file
Push the branch git-exercise-4 to GitHub.
On GitHub, go to the branch git-exercise-4 and add a color in the last line of the file colors.txt, commit your changes
On your computer, add a color in the first line of the file colors.txt, add and commit your changes
Push the branch git-exercise-4 to GitHub. Discuss what is happening and how to solve it.

Exercise 5

Objective: Learn to handle a common mistake of forgetting to checkout to the right branch, when already having a few commits pushed.

On your assignment repository DON'T go to the main branch, make sure to stay on the branch from the previous exercise.
Create a branch git/week1/exercise-5/<your-name> and move to it
In the git folder, under /week1/session-playground, create a file named movies.txt
Add two movie names to the file movies.txt, one per line
Add and commit the changes in the movies.txt file
Push the branch git-exercise-5 to GitHub.
On GitHub, create a pull request from your new branch to main.
See what commits you have there - do you only have commits from this exercise? Do you have commits that should not be here? Discuss why it happened and how to solve this situation.

Exercise 6: Into the deeps

Objective: Get comfortable with branching. Take notes of the answers to the questions in points 14, 15, 16, 17, 18, 19, 22, 23, 25, and 26. Discuss the answers in pairs.

Create a new folder in your Desktop called branch-exercise
Using the command line go to that folder and create a new repository there (git init)
Create a new file in that folder called countries.txt
Add two country names (one per line) to the countries.txt file
Commit your changes
Create a new branch named add-countries, move to that branch
Add two more country names (one per line) to the countries.txt file
Commit your changes
Go back to main
Create a new branch named add-cities, move to that branch
Create a new file named cities.txt
Add two city names (one per line) to the cities.txt file
Commit your changes
Go back to main and take a look around your folder. Which files do you see? What are their contents?
Do git log --oneline. Which commits do you see?
Go to the add-countries branch and take a look around your folder. Which files do you see? What are their contents?
Do git log --oneline. Which commits do you see?
Go to the add-cities branch and again take a look around your folder. Which files do you see? What are their contents?
Do git log --oneline. Which commits do you see?
Now go to main
Merge the branch add-countries with main (git merge add-countries)
Take a look at your folder, which files do you see? What are their contents?
Do git log --oneline. Which commits do you see?
Now merge the branch add-cities with main (git merge add-cities)
Take a look at your folder, which files do you see? What are their contents?
Do git log --oneline. Which commits do you see?

Good evening