Add ssh key to GitHub

To connect to GitHub, you better generate an ssh key and add it to your GitHub account. This saves you from entering your user name and password every time you interact with the GitHub repository.
Generate a new ssh key by following this instruction. Just push enter to all the prompts. You don't have to set a passphrase. You just have to generate the new key and do not have to add it to the ssh-agent.
1. Type the following in the terminal, replacing the example e-mail address with yours:
```
ssh-keygen -t ed25519 -C "[email protected]"
```
- It asks you to type a passphrase but leave it blank and enter the key. If you set a passphrase, it asks you to type the passphrase every time you establish an ssh connection.
1. As it is done, type the following in the terminal to print out the public key:
```
cat ~/.ssh/id_ed25519.pub
```
- Copy the printed key. The key starts from ssh-ed25519 and ends with your email address. You need to copy the entire key.
As the ssh key is generated, register the key to your GitHub account following this instruction.

Clone RStudio Project from GitHub

Suppose that the project administrator already created a project repository named kohei-kawaguchi/Economics on GitHub. Here, kohei-kawaguchi is the user name of the repository owner and Economics is the repository name. They can be different by owners and repositories.
If it is a private repository, your GitHub account has to be registered as a collaborator to the repository. Let the administrator know your GitHub account.
Open a terminal and move to a folder in which you would like to clone the project folder.
Run the following command in the terminal to clone the project:

git clone [email protected]:kohei-kawaguchi/Economics.git

As a result, we have a folder named Economics at the folder where you run the command. In the following, I call this folder a project root folder or simply a project folder.
In RStudio, you will find a terminal tab next to the R console tab. In the following instruction, when you are asked to use a terminal, you should use the terminal in RStudio. If you start the RStudio project, the current directory is set at the project directory.
In the following, we assume that both the R console and terminal set the project folder as the current directory when you run commands.
Open RStudio and open the project from File > Open Project and navigate to the cloned project folder and choose Economics.Rproj. Then, RStudio opens the project and sets the working directory in the project folder.
Try Build > Clean and Install to make sure the project can be compiled properly.
- The details for developing an R package are found in this book. R Packages (2e) (r-pkgs.org)
There is a git tab in RStudio. However, we do not use this, because the git functionality in RStudio is unstable. We use GitHub Desktop for managing the git repository.

<aside> 💡 Configuration 3 only

</aside>

Suppose that you are provided credential information from the administrator.
Suppose that the region name is ap-northeast-1. This can be different by the project.