Can't connect to Django database in Heroku

Question

I am trying to deploy a Django application in Heroku and connect it to a database using dj-database-url . The app runs fine locally (with python manage.py runserver ) but both the heroku local web command and the Heroku deployment fail with the message:

9:47:06 PM web.1 |  ModuleNotFoundError: No module named 'dj_database_url'

However, when I go into Heroku's shell and try to install the package, it says that the requirement is already satisfied

~ $ pip install dj-database-url
Requirement already satisfied: dj-database-url in ./.heroku/python/lib/python3.6/site-packages

As a side note, I have another module called django_hosts which I use and doesn't have any problems. Here is my requirements.txt file:

dj-database-url==0.5.0
Django==2.1.1
django-hosts==3.0
psycopg2==2.7.5
pytz==2018.5

And here are the lines in production.py settings file that uses dj_database_url :

import dj_database_url
...
db_from_env = dj_database_url.config()
DATABASES['default'].update(db_from_env)

I don't know if it helps, but here are my installed apps:

I

NSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',

    # third party
    'django_hosts',

    # custom apps
    'analytics',
    'shortener',
]

I thought that maybe I need to add dj_databse_url underneath django_hosts , but it didn't work.

If you need any more information, please let me know in the comments. Cheers!

Answer 1

My solution for this issue was to add the dependency to my Pipfile and then re-generate Pipfile.lock. This was necessary despite requirements.txt already having the dependency listed.