Deploy Django project to Heroku via Codeship.io

Now that we have successfully run all the tests for our Django project on Codeship.io, we want to deploy our application. We will first setup our application with Heroku and then we will setup our Codeship.io job to deploy to Heroku on a successful build.

To setup Heroku, create an account and an app. We will create (code-camp-api). You can then follow the instructions to download and install the Heroku toolbelt. Since we have already created this project, we will skip the step about creating a new Git repository and jump to deploying our application. We will add Heroku as a remote to our git repository with the following:

heroku git:remote -a code-camp-api

Next we will do a deploy to Heroku to test it out. We will push our master branch to Heroku.

git push heroku master

To deploy our project with Codeship, we will go back to the job we have created (previous post) and add continuous deployment. We want to deploy only our master branch to Heroku. To deploy our project to Heroku, we will need to make a few modifications to our codebase, first by adding some new files and second by modifying the manage.py. The first change we will make is to add a few new files. The first file we will add is the Procfile. This is a file to tell Heroku how to run our application.

web: gunicorn project.wsgi --log-file -

The second file we will add is a runtime.txt. This will tell Heroku which python version we would like for our environment.

python-2.7.9

The third file we will add is the settings/production.py.

# settings/production.py

from project.settings.base import *
import dj_database_url

The fourth file we will add is the requirements/production.txt.

-r base.txt
dj-database-url==0.3.0
dj-static==0.0.6
django-toolbelt==0.0.1
gunicorn==19.0.0
psycopg2==2.5.4
static3==0.5.1
wsgiref==0.1.2

Finally we will point our top level requirements.txt to our requirements/production.txt.

-r requirements/production.txt

The second change we will make is only for this application so that we can run with different settings files. The applications that I have worked on have had different settings files so that we can changed based on our environment. We will modify the manage.py file to allow Heroku to be able to handle our multiple settings files. By default, we will assume that you are running with production settings. However, if the second argument (manage.py is the first argument) is test, we should use our test settings. This is used mainly for our Codeship job when running the tests.

# manage.py

#!/usr/bin/env python
import os
import sys

if __name__ == "__main__":
    settings_file = 'production'
    args = sys.argv
    if sys.argv[1] == 'test':
        settings_file = 'test'
        args = [sys.argv[0]] + sys.argv[2:]
    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "project.settings.{}".format(settings_file))
    from django.core.management import execute_from_command_line
    execute_from_command_line(args)

With all this done, you will now be able to push code to our master branch, run the tests, and deploy to Heroku if all tests pass.