Can you run your entire working environment within a Docker container? I’m going to find out. To get started we’ll need a computer running Docker; in my case a 16” Intel Macbook Pro with Docker Desktop.
Alpine
Let’s talk the wrong path… I started down the path of using Alpine Linux as my base image. This
seemed like a good fit. Small image, apk installs binaries very quickly for rebuilds, and is
something I’ve considered playing with for a while. What went wrong? Ruby will not compile for
me. I tried various versions (3.0.3, 3.1, 2.7.4), from various sources (rbenv, asdf, and Ruby
source). I need the ability to switch ruby versions, so getting rbenv of asdf working is rather
important. Each build ended with:
uninitialized constant Kernel::Monitor (NameError)
Every-freaking-time! Found a few references to this error online, but no solutions. May revisit later, but unsolved as of now.
Ubuntu
Next up? Ubuntu! I know normal Ubuntu works. Guess what? It compiles Ruby! That’s a great
start. What’s next? Docker in Docker. Should be easy, right? Take a look at get.docker.com,
and get Docker up and running, mount in /var/run/docker.sock, good to go. Right? Right? Nope.
Access denied to the socket. Turns out that on MacOS, you have to mount a “magic” file, not the
normal socket: /var/run/docker.raw.sock. That file doesn’t exist on your system? Mine either!
But guess what? If you mount it, Docker starts working. What the actual 🤬? Anyway, it’s working.
Ok, things look good! Then comes the mount issues. When you allow Docker to create the folder in
the container, the location with be chowned to root. Not good. Sprinkle mkdir into Dockerfile.
That includes a SSH_AUTH_SOCK, which is stored in an unpredictable location. Entrypoint for
chown.
Ok, so I think that is everything. docker compose up - Oh crap. How do I forward ports into
the workstation? I could try to force everything onto a common port. So the first thing I have to
learn in order to do anything is to set the port. Yikes. That’s a huge stop.
Conclusion
I’m shelving this project for now. If you’re interested in my progress, feel free to check out the workstation branch on Github. I may try again at a later date, but for now I’m going to shelve it at ~6 hours of work.