SSH Key

Generation

We need to generate SSH keys which are going to be used by GitHub to authenticate you. You can think of it as a way to log in, but different from the well known username/password pair.

If you already generated keys that you already use with other services, you can skip this step.

Open a terminal and copy-paste this command, replacing the email with yours (the same one you used to create your GitHub account).

mkdir -p ~/.ssh && ssh-keygen -t ed25519 -o -a 100 -f ~/.ssh/id_ed25519 -C "TYPE_YOUR_EMAIL@HERE.com"

It will prompt for information. Just press enter until it asks for a passphrase.

⚠️ When asked for a passphrase, put something you want and that you'll remember. It's a password to protect your private key stored on your hard drive.

⚠️ When you you type your passphrase, nothing will show up on the screen, that's normal. This is a security feature to mask not only your passphrase as a whole but also its length. Just type your passphrase and when you're done, press ENTER.

Giving your public key to GitHub

Now, you will give your public key to GitHub.

In your terminal copy-paste the following command:

cat ~/.ssh/id_ed25519.pub

It will prompt on the screen the content of the id_ed25519.pub file.

• Copy that text from ssh to the end of your email address
• Go to github.com/settings/ssh
• Click on the green button New SSH key
• Fill in the Title with your computer name (Macbook Pro for instance)
• Paste the key
• Finish by clicking on the Add SSH key green button.

To check that this step is completed, in the terminal run this.

ssh -T git@github.com

⚠️ You will be prompted a warning, type yes then ENTER.

This is the expected result:

# Hi --------! You've successfully authenticated, but GitHub does not provide shell access

✔️ If you got this message, the key was added to GitHub successfully 👍

❌ If you encountered an error, you will have to try again. Do not hesitate to contact a teacher.

If ssh -T git@github.com does not work

Try running this command before trying again:

ssh-add ~/.ssh/id_ed25519

GitHub CLI

CLI is the acronym of Command-line Interface.

In this section, we will install GitHub CLI to perform useful actions with GitHub data directly from the terminal.

It should already be installed on your computer from the previous commands.

First in order to login, copy-paste the following command in your terminal:

⚠️ DO NOT edit the email

gh auth login -s 'user:email' -w

You will get the following output:

! First copy your one-time code: 0EF9-D015
- Press Enter to open github.com in your browser...

Select and copy the code (0EF9-D015 in the example), then press ENTER.

Your browser will open and ask you to authorize GitHub CLI to use your GitHub account. Accept and wait a bit.

Come back to the terminal, press ENTER again, and that's it.

To check that you are properly connected, type:

gh auth status

✔️ If you get Logged in to github.com as <YOUR USERNAME> , then all good 👍

❌ If not, contact a teacher.

Then run the following configuration line:

gh config set git_protocol ssh