Link a Local Repository to GitHub¶
Version control really comes into its own when we begin to collaborate with other people. We already have most of the machinery we need to do this; the only thing missing is to copy changes from one repository to another.
Systems like Git allow us to move work between any two repositories. In practice, though, it’s easiest to use one copy as a central hub, and to keep it on the web rather than on someone’s laptop. Most programmers use hosting services like GitHub, BitBucket or GitLab to hold those master copies.
Let’s start by sharing the changes we’ve made to our current project with the
world. Log in to GitHub, then click on the icon in the top right corner to
create a new repository called my_first_repo
:
Name your repository “my_first_repo” and then click “Create Repository”:
As soon as the repository is created, GitHub displays a page with a URL and some information on how to configure your local repository:
This effectively does the following on GitHub’s servers:
$ mkdir my_first_repo
$ cd my_first_repo
$ git init
If you remember back to the earlier lesson where we added and
committed our earlier work on notes.txt
, we had a diagram of the local repository
which looked like this:
Now we have two repositories: the local repository resembles the diagram above, and the repository of the same name hosted on the GitHub servers is completely empty.
Note that our local repository still contains our earlier work on notes.txt
, but the
remote repository on GitHub doesn’t contain any memory of notes.txt
yet.
The next step is to connect the two repositories. We do this by making the GitHub repository a “remote” for the local repository. The home page of the repository on GitHub includes the string we need to identify it:
Copy that URL from the browser, go into the local my_first_repo
repository, and run
this command:
$ git remote add origin git@github.com:eriksf/my_first_repo.git
Make sure to use the URL for your repository rather than mine: the only
difference should be your username instead of eriksf
. If you want to switch to
using SSH for authentication (recommended), see Generating a new SSH key
and Adding a new SSH key to your GitHub account.
We can check that the command has worked by running git remote -v
:
$ git remote -v
origin git@github.com:eriksf/my_first_repo.git (fetch)
origin git@github.com:eriksf/my_first_repo.git (push)
The name origin
is a local nickname for your remote repository. We could use
something else if we wanted to, but origin
is by far the most common choice.
Once the nickname origin
is set up, this command will push the changes from
our local repository to the repository on GitHub:
$ git push -u origin main
Enumerating objects: 12, done.
Counting objects: 100% (12/12), done.
Delta compression using up to 56 threads
Compressing objects: 100% (8/8), done.
Writing objects: 100% (12/12), 1.09 KiB | 560.00 KiB/s, done.
Total 12 (delta 3), reused 0 (delta 0)
remote: Resolving deltas: 100% (3/3), done.
To github.com:eriksf/my_first_repo.git
* [new branch] main -> main
Branch 'main' set up to track remote branch 'main' from 'origin'.
Proxy¶
If the network you are connected to uses a proxy, there is a chance that your last command failed with “Could not resolve hostname” as the error message. To solve this issue, you need to tell Git about the proxy:
$ git config --global http.proxy http://user:password@proxy.url
$ git config --global https.proxy http://user:password@proxy.url
When you connect to another network that doesn’t use a proxy, you will need to tell Git to disable the proxy using:
$ git config --global --unset http.proxy
$ git config --global --unset https.proxy
Clone the Repository¶
Spend a few minutes browsing the web interface for GitHub. Now, anyone can make a full copy of my_first_repo
including all the commit history by performing:
$ git clone git@github.com:eriksf/my_first_repo.git
Cloning into 'my_first_repo'...
remote: Enumerating objects: 12, done.
remote: Counting objects: 100% (12/12), done.
remote: Compressing objects: 100% (5/5), done.
remote: Total 12 (delta 3), reused 12 (delta 3), pack-reused 0
Receiving objects: 100% (12/12), done.
Resolving deltas: 100% (3/3), done.