Creating a Repository

Overview

Questions

• Where does Git store information?

Objectives

• Create a local Git repository.
• Describe the purpose of the .git directory.

Once Git is configured, we can start using it. Let’s imagine we want to create a simple web page about our work. We can track revisions to the page using git and, later, publish it using GitHub pages.

First, let’s create a new directory in the Desktop folder for our work and then change the current working directory to the newly created one:

BASH

$ cd ~/Desktop
$ mkdir simple-site
$ cd simple-site

Then we tell Git to make simple-site a repository -- a place where Git can store versions of our files:

BASH

$ git init

It is important to note that git init will create a repository that can include subdirectories and their files—there is no need to create separate repositories nested within the simple-site repository, whether subdirectories are present from the beginning or added later. Also, note that the creation of the simple-site directory and its initialization as a repository are completely separate processes.

If we use ls to show the directory’s contents, it appears that nothing has changed:

BASH

$ ls

But if we add the -a flag to show everything, we can see that Git has created a hidden directory within simple-site called .git:

BASH

$ ls -a

OUTPUT

.	..	.git

Git uses this special subdirectory to store all the information about the project, including the tracked files and sub-directories located within the project’s directory. If we ever delete the .git subdirectory, we will lose the project’s history.

Next, we will change the default branch to be called main. This might be the default branch depending on your settings and version of git. See the setup episode for more information on this change.

BASH

$ git checkout -b main

OUTPUT

Switched to a new branch 'main'

We can check that everything is set up correctly by asking Git to tell us the status of our project:

BASH

$ git status

OUTPUT

On branch main

No commits yet

nothing to commit (create/copy files and use "git add" to track)

If you are using a different version of git, the exact wording of the output might be slightly different.

Places to Create Git Repositories

Imagine you create a directory for your website images:

BASH

$ cd ~/Desktop   # return to Desktop directory
$ cd simple-site # go into simple-site directory, which is already a Git repository
$ ls -a          # ensure the .git subdirectory is still present in the simple-site directory
$ mkdir images    # make a subdirectory simple-site/images
$ cd images       # go into images subdirectory
$ git init       # make the images subdirectory a Git repository
$ ls -a          # ensure the .git subdirectory is present indicating we have created a new Git repository

Is the git init command, run inside the images subdirectory, required for tracking files stored in the images subdirectory?

Show me the solution

You don’t need to make the images subdirectory a Git repository because the simple-site repository can track any files, sub-directories, and subdirectory files under the simple-site directory.

Additionally, Git repositories can interfere with each other if they are “nested”: the outer repository will try to version-control the inner repository. Therefore, it’s best to create each new Git repository in a separate directory. To be sure that there is no conflicting repository in the directory, check the output of git status. If it looks like the following, you are good to go to create a new repository as shown above:

BASH

$ git status

OUTPUT

fatal: Not a git repository (or any of the parent directories): .git

Correcting git init Mistakes

Can you undo the last git init in the images subdirectory?

Solution – USE WITH CAUTION!

Background

Removing files from a Git repository needs to be done with caution. But we have not learned yet how to tell Git to track a particular file; we will learn this in the next episode. Files that are not tracked by Git can easily be removed like any other “ordinary” files with

BASH

$ rm filename

Similarly a directory can be removed using rm -r dirname or rm -rf dirname. If the files or folder being removed in this fashion are tracked by Git, then their removal becomes another change that we will need to track, as we will see in the next episode.

Solution

Git keeps all of its files in the .git directory. To recover from this little mistake, you can just remove the .git folder in the images subdirectory by running the following command from inside the simple-site directory:

BASH

$ rm -rf images/.git

But be careful! Running this command in the wrong directory will remove the entire Git history of a project you might want to keep. Therefore, always check your current directory using the command pwd.

Key Points

• git init initializes a repository.
• Git stores all of its repository data in the .git directory.