Docker'd Django

Django, Postgres, and Redis, all in Docker

This is a boilerplate repo intended for quickly starting a new Django project with PostgreSQL and Redis support, all running within Docker containers. A Nginx service is also defined to enable immediate access to the site over port 80.

Prerequisites

Docker
Pipenv
- Make sure Python3 is available
- Enables pipenv install to set up libraries locally for the editor to crawl. The Django container also uses Pipenv to install dependencies to encourage use of this new Python package management tool.

Getting started

Clone this repo
Delete the .git folder
- rm -rf .git/
Create a new git repo
- git init
- git add .
- git commit -m "Initial Commit"
Install Python dependencies in a Python3 virtual environment
- pipenv install --three
Create a new Django project
- pipenv run django-admin startproject appname _app/
Make the following changes to your Django project's settings.py:

# appname/settings.py
import os

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = os.getenv('DJANGO_SECRET_KEY')

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = os.getenv('DEBUG', False) == 'true'

ALLOWED_HOSTS = [
    'localhost',
]

INSTALLED_APPS = [
    # ...snip...
    'django_redis',
]

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': os.getenv('POSTGRES_USER'),
        'USER': os.getenv('POSTGRES_USER'),
        'PASSWORD': os.getenv('POSTGRES_PASSWORD'),
        'HOST': 'db',
        'PORT': 5432,
    }
}

STATIC_ROOT = 'static'

# django-redis
CACHES = {
    'default': {
        'BACKEND': 'django_redis.cache.RedisCache',
        'LOCATION': 'redis://redis:6379/1',
        'OPTIONS': {
            'CLIENT_CLASS': 'django_redis.client.DefaultClient',
        }
    }
}
SESSION_ENGINE = 'django.contrib.sessions.backends.cache'
SESSION_CACHE_ALIAS = 'default'

Update the .env file to specify values for the environment variables defined within
Start Django for development
- docker-compose up

Components

Dockerfile

Builds the Django container. The container is derived from the standard python:3.7 image and will run Django's colletstatic when being built.

docker-compose.yml

Tasked with spinning up three containers: the above container for Django, one for PostgreSQL, and one for Redis.

By default an Nginx container is also created to reverse-proxy requests to Django and serve static files. In this configuration, the Django server will be available on port 80 during production.

If the Nginx container is removed, Docker can be accessed directly on port 8000. Static files can then be served from the static_files_volume Docker volume.

docker-compose.override.yml

Loads automatically when running a standard docker-compose up. These values are intended for development purposes as they tweak the container configurations in the following way:

Make the Postgres container accessible externally on port 5432
Make the site available through Nginx at http://localhost:8000
Start gunicorn to reload when it detects a file change
Set an environmental flag telling Django that it is running in debug mode

Pipfile/Pipfile.lock

Includes Python packages needed to make Django, Postgre, and Redis work together.

.env

Contains environment variables for the containers. Several variables are included for configuring Postgres and Django secrets.

.editorconfig

Defines some common settings to help ensure consistency of styling across files.

.flake8

Configures the flake8 Python linter. Includes a few common settings to my personal preferences.

.vscode/settings.json

Helps configure the Python plugin to lint with flake8. A placeholder Python interpreter setting is left in to simplify pointing to the local virtual environment created with Pipenv.

_app/gunicorn.cfg

Defines settings for gunicorn, including a port binding, workers, and an gunicorn-specific error log.

_app/nginx.conf

Establishes a reverse-proxy to Django, and serves Django static files.

demmsnt/docker_cms