Docker + Django + Postgres Add-on + Heroku

So I'm running through the following:

• Created a Dockerfile and a docker-compose.yml to develop a django app locally, nothing to do here, everything works just fine.

• Dockerfile

  FROM python:3
  ENV PYTHONUNBUFFERED 1
  RUN mkdir /code
  WORKDIR /code
  ADD requirements.txt /code/
  RUN pip install -r requirements.txt
  ADD . /code/

• All it does is fetches python3 image, copies the code from my source folder to the docker image

• Then I'm trying to deploy this to heroku, so I added postgres add-on on heroku apps, and configured it using dj_database_url, with the following command on my settings.py file : DATABASES = {} DATABASES['default'] = dj_database_url.config()

• After that I pushed my application to heroku using heroku container:push web and it got pushed to my app no problem at all...

• The final piece is when I open my application using heroku open it says I got an error: Application error An error occurred in the application and your page could not be served. If you are the application owner, check your logs for details.

• This is what get printed on the heroku website

• Now, when I log using heroku logs -t, it says that exited with code 0, then it crashes

What am I missing?

• Plus: when I run heroku run web python manage.py migrate it migrates the data on the heroku app
• Plus 2: when I run heroku run web python manage.py runserver it says is running on 127.0.0.1:8000

EDIT 1: If you want to reproduce the problem you can clone all my code in the following git repo: https://github.com/giovanniKleinCampigoto/djangoherokuproblem.git

EDIT 2:

In this official tutorial: https://devcenter.heroku.com/articles/deploying-python , says to use virtualenv, but I'm using docker, so I don't really know how to proceed...

EDIT 3: Also, I noticed that when I push the image to heroku using: heroku container:push web, the server re-deploys, but instead of running whatever is on the procfile it just logs this: Starting process with command python3]

EDIT 4: When running heroku local web, and editing the Procfile to run docker-compose up works just fine, the problem is with the upload to heroku's server...not sure if I should edit the file to just python manage.py runserver...

docker-compose.yml

version: '2'

services:
  web:
    build: .
    env_file: composeexample/.env
    command: python3 manage.py runserver 0.0.0.0:8000
    volumes:
      - .:/code
    ports:
      - "8000:8000"