Where to run collectstatic when deploying django app to heroku using docker?
After confirming with Heroku support, this does indeed appear to be a bit of a catch-22.
The solution was to put collectstatic
in the Dockerfile so that it runs during build time and the files persist.
We got around not having a secret key config var by setting a default secret key using the get_random_secret_key
function from Django.
The run phase uses the secret key from the Heroku config vars, so we aren't actually changing the secret key every time -- the default only applies to the build process. collectstatic
doesn't index on the secret key, so this is fine.
In settings.py
from django.core.management.utils import get_random_secret_key...SECRET_KEY = os.getenv('DJANGO_SECRET_KEY', default=get_random_secret_key())
I don't use heroku so can't test, but you should be able to run collect static before you run the app;
Dockerfile
# Pull base imageFROM python:3.7-slim# Set environment variblesENV PYTHONDONTWRITEBYTECODE 1ENV PYTHONUNBUFFERED 1# Set work directoryWORKDIR /code/# Install dependenciesRUN pip install pipenvCOPY Pipfile Pipfile.lock .RUN pipenv install --system# Copy projectCOPY . .# Collect static filesRUN python manage.py collectstatic --noinput# run gunicornCMD gunicorn hello_django.wsgi:application --bind 0.0.0.0:$PORT
You could also not run collectstatic
in your dockerfile, or event run the application because these can be ran by heroku.yml
, for example;
build: docker: web: Dockerfile config: DJANGO_SETTINGS_MODULE: project.settingsrun: web: gunicorn backend.config.wsgi:application --bind 0.0.0.0:$PORTrelease: image: web command: - python manage.py collectstatic --noinput
You also shouldn't need to mkdir
for your working directory. Just set WORKDIR /code/
early in your dockerfile and after that things will run based on that directory.
There's a decent article on this here; https://testdriven.io/blog/deploying-django-to-heroku-with-docker/