Dockerfile

# Use the official Python image from the Docker Hub
FROM python:3.7.7

# These two environment variables prevent __pycache__/ files.
ENV PYTHONUNBUFFERED 1
ENV PYTHONDONTWRITEBYTECODE 1

RUN apt-get update \
    && apt-get install -y netcat

# Create an app user in the app group. 
RUN useradd --user-group --create-home --no-log-init --shell /bin/bash app

ENV APP_HOME=/home/app/web

# Change the workdir.
WORKDIR $APP_HOME

COPY requirements.txt $APP_HOME
RUN pip install --upgrade pip
RUN pip install -r requirements.txt

# Install Pillow if environment build arg is set to development
ARG environment=production
RUN if [ "x$environment" = "development" ]; then echo "\nInstalling Pillow to serve media files in development" pip install Pillow ; fi

# Create directories for static and media files
RUN mkdir -p $APP_HOME/static
RUN mkdir -p $APP_HOME/media/images

# Copy the rest of the code. 
COPY ./homepage $APP_HOME

# Change ownership of directory to avoid permission denied errors.
RUN chown -R app:app $APP_HOME

USER app:app

ENTRYPOINT ["/home/app/web/entrypoint.sh"]