/heroku_deployment

MIT LicenseMIT

How to Deploy Django Applications on Heroku

Install heroku CLI

Sign up to Heroku.

Then install the Heroku Toolbelt. It is a command line tool to manage your Heroku apps

After installing the Heroku Toolbelt, open a terminal and login to your account:

$ heroku login
Enter your Heroku details.
Email:herokuregistration@herokudeployment.com <Enter Your Own Email>
Password <Heroku password>
Authentication successful.

Preparing the Application

In this tutorial I will deploy an existing project, Django Blog

You must

  • Have asics of django concept ie apps, settings, urls, basics of databases eg
  • Have django application that you want to deploy to heroku
  • Be familiar with working with virtual environments
  • Your deployment db is postgres

tested django versions

  • django 1.11
  • django 2.2.5

Ready to start deployment

We need to add the following to our 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.

Procfile

Heroku apps include a Procfile that specifies the commands that are executed by the app’s dynos.

For more information read on the heroku documentation.

Create a file named Procfile in the project root then add:

web: gunicorn your_project_name.wsgi

Runtime.txt

This file contains the python version you are using for heroku to use, create runtime.txt in your project root and add your python version.

python-3.6.8 <Replace with your current python version.>

List of Heroku Python Runtimes.

Whitenoise: Django Static Files settings

Lets first configure static related parameter in settings.py

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'),
)

Turns out django does not support serving static files in production. However, WhiteNoise project can integrate into your Django application, and was designed with exactly this purpose in mind.

Lets first install Whitenoise pip install whitenoise

NOTE Adding whitenoise to wsgi.py has been deprecated

Next, install WhiteNoise into your Django application. This is done in settings.py’s middleware section (at the top):

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

Add the following setting to settings.py in the static files section to enable gzip functionality.

# Simplified static file serving.
# https://warehouse.python.org/project/whitenoise/

STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage'

Optional but very helpfull settings

python-decouple and dj-database-url

Python Decouple is a must have app if you are developing with Django. It’s important to keep your application credentials like API Keys, Amazon S3, email parameters, database parameters safe, specially if it’s an open source repository. Also no more development_settings.py and production_settings.py, use just one settings.py for your whole project.

Install it via pip install python-decouple

dj-database-url is a simple Django utility allows you to utilize the 12factor inspired DATABASE_URL environment variable to configure your Django application.

Install it via pip install dj-database-url

Requirements.txt

If your under a virtual environment run the command below to generate the requirements.txt file which heroku will use to install python package dependencies

pip freeze > requirements.txt Make sure you have the following packages if not install the using pip then run the command above again

dj-database-url==0.5.0
Django==1.11.5
gunicorn==19.9.0
Pillow==6.2.0
pkg-resources==0.0.0 **A MUST Remove if present**
psycopg2==2.8.3
python-decouple==3.1
pytz==2019.2
whitenoise==4.1.4

If you are following along with this process you should use the provided requirements.txt as you need to install more python packages, for any app just make sure you have the above packages as a plus.

Firts create a .env file and add it to .gitignore so you don’t commit any sensitive data to your remote repository.

Then add the database url to your .env file in the following format postgres://<username>:<password>@<address>:<port>/<database_name>, see example below

DATABASE_URL='postgres://charles:1234@localhost:5432/articles'
  • Then replace your database settings in settings.py with

.env

#just an example, dont share your .env settings
DATABASE_URL='postgres://charles:1234@localhost:5432/articles'
SECRET_KEY='342s(s(!hsjd998sde8$=o4$3m!(o+kce2^97kp6#ujhi'
DEBUG=True 
ALLOWED_HOSTS='.localhost', '.herokuapp.com', '.127.0.0.1'

We then edit settings.py to enable decouple to use the .env configurations.

import os
import dj_database_url
from decouple import config,Csv

SECRET_KEY = config('SECRET_KEY')


DEBUG = config('DEBUG', default=False, cast=bool)
   DATABASES = {
       'default': dj_database_url.config(
           default=config('DATABASE_URL')
       )
   }

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

ALLOWED_HOSTS = config('ALLOWED_HOSTS', cast=Csv())

Lets deploy now

First make sure you are in the root directory of the repository you want to deploy

Next create the heroku app

heroku create aerblog

Create a postgres addon to your heroku app

heroku addons:create heroku-postgresql:hobby-dev
Set heroku configurations

Next we log in to Heroku dashboard to access our app and configure it

Heroku dashboard

Click on the Settings menu and then on the button Reveal Config Vars: Next add all the environment vaiables, by default you should have DATABASE_URI configuration created after installing postgres to heroku.

Alternative

On terminal

heroku config:set <Enter an item from your .env file>
heroku config:set ALLOWED_HOSTS='*'
SECRET_KEY=wlpwtk4q_ku##b#%-@mga!4!vj(rw1%ug$m&312a69oi=klr0#
heroku config:set DEBUG=False

Remember to first set DEBUG to false and confirm that you have added all the confuguration variables needed.

Heroku dashboard

pushing to heroku

confirm that your application is running as expected before pushing, runtime errors will cause deployment to fail so make sure you have no bugs, you have all the following Procfile, requirements.txt with all required packages and runtime.txt .

Confirm App is working

On terminal

python manage.py runserver
    or
gunicorn <projectname>..wsgi

Pushing to heroku

git push heroku master

If you did everything correctly then the deployment should be done after a while with an output like this

Heroku dashboard

remote:          Running setup.py install for psycopg2: started
remote:            Running setup.py install for psycopg2: finished with status 'done'
remote:          Running setup.py install for python-decouple: started
remote:            Running setup.py install for python-decouple: finished with status 'done'
remote:        Successfully installed Django-1.11.5 Pillow-6.2.0 dj-database-url-0.5.0 gunicorn-19.9.0 psycopg2-2.8.3 python-decouple-3.1 pytz-2019.2 whitenoise-4.1.4
remote: 
remote: -----> Discovering process types
remote:        Procfile declares types -> web
remote: 
remote: -----> Compressing...
remote:        Done: 52.8M
remote: -----> Launching...
remote:        Released v9
remote:        https://areblog.herokuapp.com/ deployed to Heroku
remote: 
remote: Verifying deploy... done.
To https://git.heroku.com/areblog.git
 * [new branch]      master -> master

Run migrations

heroku run python manage.py migrate

If you wish to push your local database My preferred method

If you instead wish to push your postgres database data to heroku then run

heroku pg:push <db_name> DATABASE_URL --app <heroku_app_name>
eg heroku pg:push <db_name> DATABASE_URL --app <heroku_app_name>

You can the open the app in your browser blog

Comment

This process is easy to follow but requres you to be keen while dealing with the process.

For colaboration

email me at mikeycharlesm7@gmail.com