docs: update docker development instructions

[eatyourgreens]

When you're developing locally with Docker, you need to install the course materials first.

[alasdairwilson]

So there is supposed to be flexibility here in terms of a build-arg, if you pass material_method=pull it then pulls the material, default is copy which means copying it from the base directory on build, but I think this should be explained in the docs (and probably tested) in a separate PR.

[alasdairwilson]

Actually, the reason why we addd the python script to pull material is so you didnt need the node/js stuff installed to do it.

Since the point of this is developing in the container, pontentially because you don't want to install it locally, could you change this to use the python script which almost certainly is installed, or at least to point out this alternative exists.

[eatyourgreens]

.material is mounted as a volume in local dev, so that you can edit the course material locally (rather than having to edit files inside the running container.)

[alasdairwilson]

Yeah sorry, I get that, it just used to do that automatically (populate the material folder before build) as long as you told it to pull with the build arg. Unless that functionality has been broken with subsequent changes.

In any sense, the suggestion was to swap this to the python script since the whole point of the docker environment is to not have to install the node packages locally since yarn pullmat requires node, ts, etc. to be there via a yarn install to be run.

Since we can't separate out the specific dependencies in that script from the project (the git dependency) sensibly and, even if we did you would still need to install node first, whereas python should be on most anyone's system and we define the only 2 smalkl depencies (gitpython and pyyaml) in the requirements.txt file, it makes much more sense to use that to pre-pull material rather than the ts script.

[eatyourgreens]

Ah right, got you. Still got some problems here trying to help the ICR people get Gutenberg up and running from a clean install for the hackday. 😞

[eatyourgreens]

I've changed it to python scripts/pull_material.py.