Deploy Django App in Heroku ###########################*

7. Set Up¶

Requirements-

Git installed locally
Postgres installed locally, if running the app locally

https://devcenter.heroku.com/articles/git

Install Heroku CLI into Ubuntu. Then login

$sudo snap install heroku --classid
# or if using apt
$ sudo apt install heroku
 $ heroku login
›   Warning: heroku update available from 7.42.4 to 7.42.6.
heroku: Press any key to open up the browser to login or q to exit:

Update Heroku, I believe it requires a restart after the update

$ snap refresh heroku
# or if using apt
$ heroku update

8. Prepare the App¶

As a security measure to prevent HTTP Host header attacks add an ‘*’ to ALLOWED_HOSTS. This will match anything and your are responsible for the validation of the Host header

# pages_project/settings.py
ALLOWED_HOSTS = ['*']

8.1. Install gunicorn¶

::: $ pip install gunicorn $ pip freeze > requirements.txt

8.2. Define a Procfile¶

The Procfile is a text file in the root directory of the application. The below declares a single process type= web. This process type will be attached to the HTTP routing stack of Heroku

web: gunicorn <my_project_name>.wsgi --log-file -

9. Deploy the App¶

9.1. Create an app in Heroku¶

$ heroku create <unique app name in heroku>     # app name optional
Creating app... done, ⬢ sheltered-brook-17119
https://sheltered-brook-17119.herokuapp.com/ | https://git.heroku.com/sheltered-brook-17119.git

Add a remote to your local repository. Note that heroku only deploys code to the master or main branch

$ heroku git:remote -a sheltered-brook-17119
set git remote heroku to https://git.heroku.com/sheltered-brook-17119.git
# check the remote was created
$ git remote -v
heroku  https://git.heroku.com/sheltered-brook-17119.git (fetch)
heroku  https://git.heroku.com/sheltered-brook-17119.git (push)
# rename a remote if you wish
$ git remote rename heroku heroku-staging

10. Configure Static Files on Heroku¶

If you wish you can tell Heroku to ignore or disable static files like CSS and javascript

$ heroku config:set DISABLE_COLLECTSTATIC=1

To configure Heroku to serve static files add the following to the settings.py file

BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.9/howto/static-files/
STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')
STATIC_URL = '/static/'

# Extra places for collectstatic to find static files.
STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'static'),
)

Also Django won’t automatically create the target directory STATIC_ROOT that collectstatic uses. If directory is not available you may need to create this directory for collectstatic. Git does not support empty file directories so you may have to create a file inside STATIC_ROOT, maybe an __init.py__ file.

10.1. WhiteNoise¶

Django does not support serving static files in production, but WhiteNoise can integrate static files into the Django application. First install WhiteNoise with pip.

$ pip install whitenoise
$ freeze > requirements.txt  # don't forget

Add WhiteNoise into the settings.py middleware section.

MIDDLEWARE_CLASSES = (
# Simplified static file serving.
# https://warehouse.python.org/project/whitenoise/
'whitenoise.middleware.WhiteNoiseMiddleware',

10.2. Debugging¶

If collectstatic failed you can get additional feedback with

$ heroku config:set DEBUG_COLLECTSTATIC=1

11. Heroku Simplified DevOps¶

$ git push <remote_name> <branch_name>

11.1. Some Heroku Commands¶

heroku login
heroku ps:scale web=1 # run 1 instance of my web process/dyno
heroku open # start the web page
heroku run bash # in bash use <exit> to leave

11.2. Set Heroku Python Version¶

Create runtime.txt. Insert ‘python-3.8.2. or correct python version in runtime.txt with no spaces. Correct formatting is essential

11.3. Set Up Postgres DB¶

May need to redo migrations if data not pushed up.