Docker can't find installed modules by pipenv in Django project

Question

So I'm trying to build and run a docker image with pipfiles as the package handler. But even after a seemingly successful build, it cannot find the 'django' module. I am on Windows 10 by the way.

Here is my pipfile

[[source]]
name = "pypi"
url = "https://pypi.org/simple"
verify_ssl = true

[dev-packages]

[packages]
django-jquery = "*"
anyconfig = "*"
asgiref = "*"
crispy-forms-materialize = "*"
django-crispy-forms = "*"
django-ranged-response = "*"
pytz = "*"
six = "*"
sqlparse = "*"
Django = "*"
Pillow = "*"

[requires]
python_version = "3.8"

My Dockerfile

FROM python:3.8
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
RUN pip install pipenv
RUN pipenv install
COPY . /code/

CMD pipenv run python manage.py runserver

And docker-compose.yml file

version: '3'

services:
  web:
    build: .
    command: pipenv run python manage.py runserver 0.0.0.0:8000
    ports:
      - "8000:8000"

Here is the docker build log

$ docker-compose build --pull
Building web
Step 1/8 : FROM python:3.8
3.8: Pulling from library/python
Digest: sha256:e02bda1a92a0dd360a976ec3ce6ebd76f6de18b57b885c0556d5af4035e1767d
Status: Image is up to date for python:3.8
 ---> d47898c6f4b0
Step 2/8 : ENV PYTHONUNBUFFERED 1
 ---> Using cache
 ---> 5330d9208341
Step 3/8 : RUN mkdir /code
 ---> Using cache
 ---> 57420ad117b3
Step 4/8 : WORKDIR /code
 ---> Using cache
 ---> 4831c4a1edf9
Step 5/8 : RUN pip install pipenv
 ---> Using cache
 ---> be3d166f236e
Step 6/8 : RUN pipenv install
 ---> Using cache
 ---> 38a63cd1032a
Step 7/8 : COPY . /code/
 ---> c86632082d57
Step 8/8 : CMD pipenv run python manage.py runserver
 ---> Running in 45b2d9ccc973
Removing intermediate container 45b2d9ccc973
 ---> d0a474b9c984
Successfully built d0a474b9c984
Successfully tagged myapp_web:latest

...And when I try to run docker-compose up

$ docker-compose up
Recreating myapp_web_1 ... done
Attaching to myapp_web_1
web_1  | Loading .env environment variables�
web_1  | Traceback (most recent call last):
web_1  |   File "manage.py", line 10, in main
web_1  |     from django.core.management import execute_from_command_line
web_1  | ModuleNotFoundError: No module named 'django'
web_1  |
web_1  | The above exception was the direct cause of the following exception:
web_1  |
web_1  | Traceback (most recent call last):
web_1  |   File "manage.py", line 21, in <module>
web_1  |     main()
web_1  |   File "manage.py", line 12, in main
web_1  |     raise ImportError(
web_1  | ImportError: Couldn't import Django. Are you sure it's installed and available on your PYTHONPATH environment variable? Did you forget to activate a virtual environment?
myapp_web_1 exited with code 1

Hopefully someone can point me to what I'm doing wrong. Thanks!

Answer 1

You haven't copied the Pipfile into your Docker image before you run pipenv install, so the install doesn't install anything. You should also consider the pipenv install --deploy --system options: since the Docker image is itself an isolation layer, you don't need to also create a virtual environment, installing into the "system" Python is fine, and that saves you the need to pipenv run later.

FROM python:3.8
ENV PYTHONUNBUFFERED 1
WORKDIR /code                 # creates the directory too
RUN pip install pipenv
COPY Pipfile Pipfile.lock ./  # <-- add this
RUN pipenv install
COPY . ./
EXPOSE 8000                   # typical metadata

# Remove "pipenv run", add the bind argument
# (No need to repeat `command:` in `docker-compose.yml`)
CMD python manage.py runserver 0.0.0.0:8000