Python
,Justfiles
,Docker
🐳 Using Just and Compose for interactive Django and Python debugging sessions
When I wrote REST APIs, I spent weeks and months writing tests and debugging without looking at the front end. It’s all JSON, after all.
For most of my projects, I will open two or three tabs. I’m running Docker Compose in tab one to see the logs as I work. I’ll use the following casey/just recipe to save some keystrokes and to standardize what running my project looks like:
# tab 1
$ just up
In my second tab, I’ll open a shell that is inside my main web or app container so that I can interact with the environment, run migrations, and run tests.
We can nitpick the meaning of “console” here, but I tend to have another just recipe for “shell” which will open a Django shell using shell_plus or something more interactive:
# tab 2
$ just console
In my third tab, I’ll run a shell session for creating git branches, switching git branches, stashing git changes, and running my linter, which I prefer to run by hand.
# tab 3
$ echo "I'm boring"
Over the last year or two, the web has returned to doing more frontend work with Django and less with REST. Using ipdb
, in my view, to figure out what’s going on has been really helpful. Trying to get ipdb
to “just work” takes a few steps in my normal workflow.
# tab 1 (probably)
# start everything
$ just start
# stop our web container
$ just stop web
# start our web container with "--service-ports"
# just start-web-with-debug
The only real magic here is using Docker’s --service-ports
, which opens ports so we may connect to the open ipdb
session when we open one in our view code.
My main justfile
for all of these recipes/workflows looks very similar to this:
# justfile
set dotenv-load := false
@build *ARGS:
docker compose build {{ ARGS }}
# opens a console
@console:
docker compose run --rm --no-deps utility/bin/bash
@down:
docker compose down
@start *ARGS:
just up --detach {{ ARGS }}
@start-web-with-debug:
docker compose run --service-ports --rm web python -m manage runserver 0.0.0.0:8000
@stop *ARGS:
docker compose down {{ ARGS }}
@up *ARGS:
docker compose up {{ ARGS }}
If you work on multiple projects, I encourage you to find patterns you can scale across them. Using Just, Make, shell scripts or even Python lightens the cognitive load when switching between them.
Saturday June 29, 2024