Deploy Django web application to Heroku

Introduction

Heroku is a cloud application platform, it facilitates the deployment of a web application.
They support several programming languages, include Python.

Install Heroku Toolbet

To install Heroku Toolbet Sign up to heroku,
Then install the Heroku Toolbet it is a very powerful command-line tool it will help you to manage your application.
After installing the Toolbet, open your Terminal/CMD and login to your account :

$ heroku login
Enter your Heroku credentials.
Email: your email
Password (typing will be hidden):
Authentication successful.

Preparing our application

place into your application

$ cd my-application/

Here is the list of things you will probably need to add to your project:

• Add a Procfile in the project root;
• Add requirements.txt file with all the requirements in the project root;
• Add Gunicorn to requirements.txt;
• A runtime.txt to specify the correct Python version in the project root;
• Configure whitenoise to serve static files.

The Procfile

• Create a file named Procfile in the project root
• Add the following content :

web: gunicorn my-application.wsgi --log-file -

Note: change my-applicatio with the name of your Django project.

The requirements.txt

Run this command, this command will list all dependencies :

$ pip freeze > requirements.txt
You should see somthing like this :
dj-database-url==version
Django==version
gunicorn==version
psycopg2==version
psycopg2-binary==version
pytz==version
whitenoise==version

The runtime.txt

Create a file named runtime.txt in the project root, and put the specific Python version your project use:

python 3.8

Set Up The Static Assets

Configure the STATIC-related parameters on settings.py:

# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/2.2/howto/static-files/
STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')
STATIC_URL = '/static/'
STATICFILES_DIRS = [
    os.path.join(BASE_DIR, "static")
]

Configure Whitenoise

Install Whitenoise

$ pip install whitenoise

Add the Whitenoise to your Django application in the wsgi.py file:

"""
WSGI config for repertoire project.
It exposes the WSGI callable as a module-level variable named ``application``.
For more information on this file, see
https://docs.djangoproject.com/en/2.2/howto/deployment/wsgi/
"""
import os
from whitenoise.django import DjangoWhiteNoise
from django.core.wsgi import get_wsgi_application
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'my-application.settings')
application = get_wsgi_application()
application = DjangoWhiteNoise(application)

Update the settings.py

STATICFILES_STORAGE = 'whitenoise.django.GzipManifestStaticFilesStorage'

Add whitenoise middleware at the top of the middleware list in settings.py

Deploy the application

Update Database Configuration in settings.py (at the bottom of the file)

import dj_database_url 
prod_db  =  dj_database_url.config(conn_max_age=500)
DATABASES['default'].update(prod_db)

Create App in Heroku from terminal

$ heroku create myapplication
Creating ⬢ myapplication... done
https://myapplication.herokuapp.com/ | https://git.heroku.com/myapplication.git

Choose any name for your app. Heroku will inform you if the name already exists

Add your app domain name to ALLOWED_HOSTS in settings.py.

ALLOWED_HOSTS = ['myapplication.herokuapp.com']

Initialize Git and connect your new app (or existing one) to Heroku Git remote repository and push the application.
in your terminal / CMD :

$ git init
$ heroku git:remote -a myapplication
$ git add .
$ commit -m "Initial commit"
$ git push heroku master

If you get an error message with collectstatic, simply disable it by instructing Heroku to ignore running the manage.py collecstatic command during the deployment process.

$ heroku config:set     DISABLE_COLLECTSTATIC=1  

Then, run :

$ git push heroku master

Migrate the database :

$ heroku run python manage.py migrate

Let me know in the comment section if you've any error.

Thank you for reading.