[PYTHON] Deploy the Django app on Heroku [Part 1]

Introduction

Record as a reminder when running the Django app on Heroku. Part 1 is about displaying the Django app's start page (It Work page) on Heroku.

Next time Deploy the Django app to Heroku [Part 2] ** My environment **

• macOS Sierra 10.12.5
• Python 3.6.1
• virtualenv 15.1.0

Things necessary

• Heroku account Reference: Heroku beginners try Hello, Heroku

• Install virtualenv (installed in python3 environment) Reference: Manage python environment with virtualenv

Configuration of the application to be made this time

The application created this time has the following configuration.

Constitution

myProject
├── venv
├── Procfile
├── db.sqlite3
├── manage.py
├── myDjango
│   ├──__pycache__
│   ├── __init__.py
│   ├── settings.py
│   ├── urls.py
│   └── wsgi.py
├── requirements.txt
└── runtime.txt

Root directory name: myProject Django project name: myDjango

procedure

Create a Django app

** Create / move project directory **

$ mkdir myProject
$ cd myProject

** Building and starting a virtual environment **

$ virtualenv venv
$ source venv/bin/activate

Build a virtual environment named venv with virtualenv venv. Run the virtual environment venv with source venv / bin / activate. (Venv) will now appear before the terminal username.

(Supplement) When you want to end the execution of the virtual environment, execute deactivate in the terminal.

** Install django-toolbelt **

$ pip install django-toolbelt

By installing django-toolbelt, the following packages will be installed.

• django (Django body)
• psycopg2 (makes postgreSQL easier to work with in Python)
• gunicorn (WSGI server running on Python)
• dj-database-url (make Django work with postgreSQL)
• dj-static (to handle static resources)

** Create a Django project **

$ django-admin.py startproject myDjango ./

Create a Django project called myDjango in your current directory.

** Change language / time zone ** Rewrite the following part of settings.py in the myDjango directory.

myDjango/settings.py

LANGUAGE_CODE = 'ja'

TIME_ZONE = 'Asia/Tokyo'

** Migrate **

$ python manage.py migrate
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
  Applying contenttypes.0001_initial... OK
  Applying auth.0001_initial... OK
  Applying admin.0001_initial... OK
  Applying admin.0002_logentry_remove_auto_add... OK
  Applying contenttypes.0002_remove_content_type_name... OK
  Applying auth.0002_alter_permission_name_max_length... OK
  Applying auth.0003_alter_user_email_max_length... OK
  Applying auth.0004_alter_user_username_opts... OK
  Applying auth.0005_alter_user_last_login_null... OK
  Applying auth.0006_require_contenttypes_0002... OK
  Applying auth.0007_alter_validators_add_error_messages... OK
  Applying auth.0008_alter_user_username_max_length... OK
  Applying sessions.0001_initial... OK

OK if it looks like this To put it simply, migration is a feature that allows you to create a table in a database in Python without writing SQL. Reference: ["Migration" that Rails beginners can easily trip over](https://www.transnet.ne.jp/2015/12/29/rails "Migration" that Rails beginners can easily trip over "colnr /" https://www.transnet. ne.jp/2015/12/29/rails "Migration" colnr / ") that beginners can easily trip over

** Start server **

$ python manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).
July 16, 2017 - 02:53:26
Django version 1.11.3, using settings 'myDjango.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

Execute python manage.py runserver and when the above display is displayed, it's OK By executing this command, you can see the app at http://127.0.0.1:8000/. Press Ctrl + C to exit.

** Check if the app starts locally ** Access http://127.0.0.1:8000/ from your browser. If all goes well, you'll see a page like the one in the image below.

Version control with git

** Creating .gitignore ** Create a .gitignore file and write the following:

.gitignore

*.pyc
venv
staticfiles
db.sqlite3

commit

$ git init
$ git add .
$ git commit -m "I created a Django app"

Deploy to Heroku

** Creating a Procfile **

$ echo "web: gunicorn myDjango.wsgi --log-file -" > Procfile

Procfile is a file that teaches Heroku what to do. Reference: Role of Heroku's Procfile

** Creating runtime.txt **

$ echo "python-3.6.1" > runtime.txt

Specify the Python version in runtime.txt.

** Creating requirements.txt **

$ pip freeze > requirements.txt

You can create a file like this

requirements.txt

dj-database-url==0.4.2
dj-static==0.0.6
Django==1.11.3
django-toolbelt==0.0.1
gunicorn==19.7.1
psycopg2==2.7.1
pytz==2017.2
static3==0.7.0

** Make the Django app available on Heroku ** Add the following to the last line of settings.py.

myDjango/settings.py

# Parse database configuration from $DATABASE_URL
import dj_database_url
db_from_env = dj_database_url.config()
DATABASES['default'].update(db_from_env)

# Honor the 'X-Forwarded-Proto' header for request.is_secure()
SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')

# Allow all host headers
ALLOWED_HOSTS = ['*']

# Static asset configuration
import os
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
STATIC_ROOT = 'staticfiles'
STATIC_URL = '/static/'

STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'static'),
)

Rewrite wsgi.py

myDjango/wsgi.py

import os

from dj_static import Cling
from django.core.wsgi import get_wsgi_application

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "myDjango.settings")

application = Cling(get_wsgi_application())

** Creating a Heroku app **

$ heroku create

** Setting Heroku environment variables **

$ heroku config:set DISABLE_COLLECTSTATIC=1

If you do not do this, you will get an error when pushing.

** Push to Heroku **

$ git add .
$ git commit -m "Made it work on Heroku"
$ git push heroku master

Push successful when remote: Verifying deploy ... done. is displayed

** Migrate on Heroku **

$ heroku run python manage.py migrate

If you run heroku run 〇〇, you can execute the command 〇〇 on heroku.

** Check if it works on Heroku **

$ heroku open

You can access the application on Heroku created this time with heroku open. If all goes well, you'll see a page like the one in the image below.

Summary

This time, I even ran a Django-made app on Heroku. Next time, we will create a model for the management site.

Next time Deploy the Django app to Heroku [Part 2]

reference

• [How to deploy a Django app to heroku in just 5 minutes](http://qiita.com/kilhyungdoo/items/ae0b4d2970bc0937e884#git version control "http://qiita.com/kilhyungdoo/items/ae0b4d2970bc0937e884# git version control ")
• Deploying Python and Django Apps on Heroku