Creating a Repository
Overview
Teaching: 10 min
Exercises: 0 minQuestions
Where does Git store information?
Objectives
Create a local Git repository.
Once Git is configured, we can start using it. Let’s create a directory for our work and then move into that directory:
$ mkdir planets
$ cd planets
Then we tell Git to make planets
a repository—a place where
Git can store versions of our files:
$ git init
If we use ls
to show the directory’s contents,
it appears that nothing has changed:
$ ls
But if we add the -a
flag to show everything,
we can see that Git has created a hidden directory within planets
called .git
:
$ ls -a
. .. .git
Git stores information about the project in this special sub-directory. If we ever delete it, 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.
git checkout -b main
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:
$ git status
If you are using a different version of git than I am, then then the exact wording of the output might be slightly different.
# On branch main
#
# Initial commit
#
nothing to commit (create/copy files and use "git add" to track)
Places to Create Git Repositories
Dracula starts a new project,
moons
, related to hisplanets
project. Despite Wolfman’s concerns, he enters the following sequence of commands to create one Git repository inside another:$ cd # return to home directory $ mkdir planets # make a new directory planets $ cd planets # go into planets $ git init # make the planets directory a Git repository $ mkdir moons # make a sub-directory planets/moons $ cd moons # go into planets/moons $ git init # make the moons sub-directory a Git repository
Why is it a bad idea to do this? (Notice here that the
planets
project is now also tracking the entiremoons
repository.) How can Dracula undo his lastgit init
?Solution
Git repositories can interfere with each other if they are “nested” in the directory of another: 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:$ git status
fatal: Not a git repository (or any of the parent directories): .git
Note that we can track files in directories within a Git:
$ touch moon phobos deimos titan # create moon files $ cd .. # return to planets directory $ ls moons # list contents of the moons directory $ git add moons/* # add all contents of planets/moons $ git status # show moons files in staging area $ git commit -m "add moon files" # commit planets/moons to planets Git repository
Similarly, we can ignore (as discussed later) entire directories, such as the
moons
directory:$ nano .gitignore # open the .gitignore file in the text editor to add the moons directory $ cat .gitignore # if you run cat afterwards, it should look like this:
moons
To recover from this little mistake, Dracula can just remove the
.git
folder in the moons subdirectory. To do so he can run the following command from inside the ‘moons’ directory:$ rm -rf moons/.git
But be careful! Running this command in the wrong directory, will remove the entire git-history of a project you might wanted to keep. Therefore, always check your current directory using the command
pwd
.
Key Points
git init
initializes a repository.