An Virtual elementaryOS Development Enviroment October 9, 2018
I’ve been working on my first (non-monetary) contribution to elementaryOS and created a clean and practical development environment along the road with a VM and X11-forwarding.
Recently I achieved something rather small, that gave me a lot of joy. I wrote my first patch for an open source piece of software. It was for the default terminal application that comes with elementaryOS. Cassidy James Blaede opened an issue on github and added the
Bytesize tag to it. This tag brought me to the issue, since I was looking for an easy entry to the elementaryOS development ecosystem. In elementaryOS, this is the tag for exactly that.
The Initial Setup
In order to be productive, I decided to work in a virtual machine. This would ensure that I didn’t clutter my system and it gave me the opportunity to roll back to certain points in the past if I did something stupid during development 1. Going back in time with virtual machine snapshots is really easy.
Creating an elementaryOS VM in elementaryOS works like this:
- Install virt-manager (I tried Gnome Boxes, but the experience wasn’t great2):
sudo apt install virt-manager qemu-kvm
- Become part of the libvirt group (e.g. logout; login)
- Use a recent ISO installer of elementaryOS and create your VM in virt-manager. I used the same installer I used to install my real physical PC (Juno Beta 2 by the way, which is surprisingly stable and polished for a beta).
I assume that you’re familiar with a terminal and have set up an SSH key. Now, in the VM enable the OpenSSH server:
sudo apt install openssh-server sudo systemctl enable ssh sudo systemctl start ssh ip -c a s
The last line will show the IP address that you need to connect to. On your host configure the connection:
Now to the nifty part. This is not witchwork, but I’m sure a lot of people don’t know this or aren’t aware how useful this is. Add an entry like this to your SSH config (
Host $vm_ip ForwardAgent yes ForwardX11 yes
BTW, you might want to add the IP address to your hosts file:
echo "$vm_ip $vm_name" | sudo tee -a /etc/hosts sed -i 's/$vm_ip/$vm_name/' ~/.ssh/config
The changes to your SSH config enabled forwarding your SSH agent and your X11 server. You need your SSH agent in the VM to work with the same credential for GitHub that you usually use, but without having to manually setting them up in the VM again.
Forwarding X11 is the really cool part: When starting an graphical editor on the command line of the VM, for example Sublime Text, it will display on your regular screen. You don’t have to have a VNC connection to the server. The other cool thing: When you’re compiling a graphical tool, like the elementaryOS terminal, it also will start on your regular screen. And as a bonus, you can have two different versions of the terminal running, at the same time. Your usual version which houses the SSH connection, and a development version, which you’re currently working on.
The Actual Environment
This step depends on the project you’re working on. Terminal’s README shows how to do it. Of course all the steps necessary are done in the VM.
Little Advice At The End (Snapshots)
Make use of snapshots (conveniently done through virt-manager’s GUI). If you feel you achieved some kind of a milestone in your VMs setup, like “all’s setup, going to clone the repo now”, you should take a snapshot.
Building this setup felt really useful, and I think it’s a good way to keep your desktop environment clean and have an easy way to build a reproducible development environment.
- You know, sometimes you install or remove some packages and when you try to revert that action somehow your system never behaves the same again… or is it just me? [return]
- It might be due to my work experience with virt-manager, but I couldn’t get a working VM for whatever reason. I quickly switched to virt-manager, so I’m not sure if I was just impatient or if something was seriously broken. I’m sure it wasn’t the latter. [return]