Django + Docker-Compose deployment to Heroku

Setting up a docker-compose django project

1. Follow the django docker-compose guide set-up here.
2. Your working directory should now contain all files listed below

• Dockerfile docker-compose.yml manage.py requirements.txt

3. Test that you app is running locally

• $ sudo docker-compose up 

 4. Navigate to localhost:8000 on your web browser to test if everything is working as expected.

---

Django production application configuration

1. Modify your Dockerfile as follows

Dockerfile

    
      FROM python:3.6.4
      ENV PYTHONUNBUFFERED 1

      ENV PORT 5000

      RUN mkdir /code
      WORKDIR /code
      ADD requirements.txt /code
      RUN pip install -r requirements
      ADD . /code

      CMD python3 manage.py runserver 0.0.0.0:$PORT 
  

2. Modify your wsgi.py file as follows

wsgi.py

    
      import os
      
      from django.core.wsgi import get_wsgi_application
      from whitenoise.django import DjangoWhiteNoise
      
      os.environ.setdefault("DJANGO_SETTINGS_MODULE", 
      "project_name.settings")
      
      application = get_wsgi_application()
      application = DjangoWhiteNoise(application)
    
  

3. Modify your settings.py as follows

settings.py

 # Copy your secret key to  .env file

import os
from decouple import config
import dj_database_url

.............. 

SECRET_KEY = config('SECRET_KEY')
DEBUG = config('DEBUG', default=False, cast=bool)
ALLOWED_HOSTS = ['.herokuapp.com/']
.......

INSTALLED_APPS = [
# ...
'whitenoise.runserver_nostatic',
'django.contrib.staticfiles',
# ...]

....... 

DATABASES = { 'default': dj_database_url.config( 
      default=config('DATABASE_URL') )
     } 

.....

MIDDLEWARE_CLASSES = [.....

 'whitenoise.middleware.WhiteNoiseMiddleware',

# ...]

.......
STATIC_URL = '/static/'
STATICFILES_DIRS = ( os.path.join(BASE_DIR, 'static'),) 
STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')
    

• Update your requirements.txt to include whitenoise==3.3.1

4. Create a .gitignore in your root directory

.gitignore

      *.pyc
      *.sqlite3
      *.env

NB: Copy the contents of this file to another file called .dockerignore

5.  Create a .env in your root directory

.env

      SECRET_KEY='pdfjsskskfiuf.............'
      DEBUG=False
    # Copy your own secret key from settings.py 

6. Finally, modify the docker-compose.yml file as follows

    
      version: '2'
       services:
        web:
         build: .
         ports:
          - "5000:5000"
         env_file: .env
         depends on:
           - db
          volumes:
             - .:/code
        db:
         image: postgres:latest
         ports:
           - "5432:5432"
    
  

 Deploy to heroku

1. Create a heroku app, together with the add-ons needed for production, e.g. postgres database:

      $ heroku login 

      $ heroku create endeesa
      $ heroku git:remote -a endeesa
      $ heroku addons: create heroku-postgresql:hobby-dev -a endeesa  

2. Configure heroku variables

3. Update your .env file
SECRET_KEY='k_^7*=x48^&f-7_mgm3$z*=-4ogj(!q+prrbi......'
DEBUG=False
DATABASE_URL='postgres://ntgdltqnyzxb1.amaz/dddie91mk0phpq'........'

4. Deploy your containerized django application to heroku

      $ heroku container:login

      $ heroku container:push web 

• Run $ heroku open, to view your live site
• You can continue with local development by running 
• $ sudo docker-compose up --build

• Note that to do this, you need to set DEBUG = TRUE inside your .env file.
• It is recommended that you modify your project to use two settings such that all in all your project is structured as follows
• settings
• base.py
• production.py
• development.py
• This way, you can import base.py in both production.py and development.py and override different variables as needed. e.g. DEBUG=False inside production.py and DEBUG=True iniside development.py.