Creating and Managing Git Repositories

Table of contents

Creating and Managing Git Repositories

Creating a new repository is often confusing to new users of Git and GitHub. Here is a simple explanation of the two options, with complete instructions on how to work with each.

The git command displays these options within the --help documentation:

start a working area (see also: git help tutorial)
   clone     Clone a repository into a new directory
   init      Create an empty Git repository or reinitialize an existing one

It is important to remember that when cloning or forking an existing repository, you will inherit the entire history of all previous commits. This is a feature: Newcomers to a project are not restricted to only the history after their arrival.

Clone

git clone is the simplest way to begin working with a repository you want connected to GitHub. The clone operation clones an entire remote repository to your local workstation.

Assuming you are authenticating to GitHub using SSH keys, here are the steps to cloning:

Within GitHub find the existing repository you want to clone.
From the repository page, find the blue “Code” button, and select the SSH tab within the dropdown. If you are using a PAT for authentication, use the HTTPS address.
Copy the address, which will look something like git@github.com:UVADS/git-basics.git (SSH) or https://github.com/UVADS/git-basics.git (HTTPS).
In the command-line on your local computer, clone the repo. If using an SSH key to authenticate to GitHub, use this format:
```
 git clone git@github.com:UVADS/git-basics.git
```
If using a PAT to authenticate to GitHub, be sure to insert your token in the clone command like this:
``` git clone https://ghp_xxxxxxxxxxxxxxx@github.com/UVADS/git-basics.git
This will create a new subdirectory with the name of the repository. You can change the name of the directory if you like.

If there are multiple branches in the GitHub repository and you want to clone them all, use these commands (using this repository as an example):

 # Using SSH
 git clone git@github.com:UVADS/git-basics.git
 cd git-basics/
 git fetch --all
 for branch in `git branch -r | grep -v HEAD`; do
   git checkout -b $branch $branch
 done

 # Using a PAT
 git clone https://ghp_xxxxxxxxxxxxxxx@github.com/UVADS/git-basics.git
 cd git-basics/
 git fetch --all
 for branch in `git branch -r | grep -v HEAD`; do
   git checkout -b $branch $branch
 done

Note that if you create a new, empty repository within GitHub, it is helpful to tick the box to include a README.md file by default. This ensures that a default branch (named main) will be created for you.

Init

Git repositories can also be created locally and connected with GitHub after creation. (In fact, there are some cases where a local git repository is used for source control but never connected to an external hub.)

To initialize a local git repository and then connect it with GitHub:

Create a directory for your new project and cd into it.
Issue the git init command to initialize the repository.
Then add a file and commit it

Create a default branch.

 mkdir project1
 echo "# foo" >> README.md
 git init
 git add README.md
 git commit -m "first commit"
 git branch -M main

Next, create an empty repository in GitHub. Do not add a README.md file in that process (leave that unchecked). You will see prompts for how to:
- Create a new repository from the command line
- Push an existing repository from the command line (the path followed below)
- Import code from another repository
Copy the SSH URL to your new repository, which will look something like git@github.com:<account>/<repo>.git

Finally, add the remote origin and push your repo using that URL:

 git remote add origin git@github.com:<account>/<repo>.git
 git push -u origin main

Fork

A fork is a copy of someone else’s repository. This is usually because you do not have access to push changes to the repository, or because the organization that controls it requires all changes come through forks and pull requests.

When you fork a repository, a complete copy is made in your own account (or Organization) in GitHub. This gives you complete control to clone and work with the code freely. You own the forked copy, so you can make additions, new functionality, and commit+push to your own fork.

Learn more about Forks

Delete

To delete a repository you have both in GitHub and on your local computer, do the following:

Locally, cd ../ to the parent directory above your project directory, and rm -Rf <project-name> to delete the entire folder. You can also use the MacOS Finder or Windows Explorer to select and delete this folder.
In GitHub, within the repository page itself, click the “Settings” tab, and scroll to the bottom. There you will find a “Delete this repository” button.