🔑 GitHub SSH manager

A lightweight, zero dependency utility for managing SSH keys for multiple GitHub repositories on a single machine. It's essentially a simplified version of the workflow described here: https://docs.github.com/developers/overview/managing-deploy-keys.

Installation

Either clone the repository as normally or copy the file contents and paste it in a new script on your machine (make sure to mark it as executable). You may also download the latest version using wget, but as always, make sure to download it separately and read it thoroughly before running it the first time.

$ sudo wget -O /usr/local/bin/gh-ssh "https://raw.githubusercontent.com/Kattjakt/github-ssh-manager/main/gh-ssh"
$ sudo chmod +x /usr/local/bin/gh-ssh
$ gh-ssh # woo!

Example usage

Presume we have a GitHub user foo with a private GitHub repository called application. We have a remote machine that must be able to access the repository in order to continuously pull the latest version, so we need to set up SSH keys and create a new Deploy Key.

Create a new labeled SSH key pair in ~/.ssh/github/foo/application/ and add it to our ssh-agent

$ gh-ssh init foo/application

We can now check the status of our SSH keys by running the following command.

$ gh-ssh ls
REPOSITORY        ACTIVE  PRIVATE KEY  PUBLIC KEY      LAST UPDATED              
foo/application   No      id_ed25519   id_ed25519.pub  Sat Dec 26 03:27:04 2020

Note that the "repositories" listed here isn't actually stored anywhere; they get inherited from the folder structure under ~/.ssh/github/. The column "active" indicates whether or not the repository is listed in ~/.ssh/config. As we see, our repository doesn't exists in there, so lets enable it!

$ gh-ssh enable foo/application

If you try running the above command yourself (and it succeeds) you'll see that it also outputs instructions for creating a Deploy Key in the GitHub web interface. For the sake of easability we also print the public key here for quick copy-paste, but of course you can just run cat ~/.ssh/github/<user>/<repo>/id_ed25519.pub at any time to retrieve your public key. You can read more about the Deploy Key process here.

When you've saved the Deploy Key you can make sure everything works by running

$ gh-ssh test foo/application

If it succeeds, great! If it didn't, it should tell you what went wrong and how to fix it.

So, to summarize: we've created an SSH key pair, added them to our ssh-agent, and created a new entry in ~/.ssh/config. The only thing that remains is to clone the repository itself. We can get the git origin URL by running the origin command:

$ gh-ssh origin foo/application
git@foo_application:foo/application.git

$ git clone $(gh-ssh origin foo/application)
Cloning into 'application'...
remote: Enumerating objects: 1, done.
remote: Counting objects: 100% (1/1), done.
Receiving objects: 100% (1/1), done.
remote: Total 1 (delta 0), reused 0 (delta 0), pack-reused 0

$ ls
application

And that's it! Run gh-ssh to print all available commands!