Ansible Django Deployment playbook.

This playbook works with (or will aim to work with) the following technologies:

• Django
• Git
• uWsgi
• Nginx
• PostgreSQL
• Celery
• Haystack
• Elastic Search
• Redis

Todo

• Security

  • close all ports and open only those required
  • dbservers:
    • only allow access into postgres port from appservers ip addresses

• Database Node

  • celery
  • haystack
  • elasticsearch

• Monitoring

  • Nagios

• Auto Scaling

  • nagios triggers to automate ansible scaling

Installation

• git clone this repo to a sensible location
• edit ~/.bash_rc (or other such file) to include an alias to the play script. alias playbook='~/Dev/ansible/play'
• copy the inventory directory to your django project source tree (see below) and put all sensitive information in this folder (assuming your project is private).
• copy the Vagrantfile to the same location.
• modify line 51 to point at this repo you cloned: ansible.playbook = "~/Dev/ansible/playbook/site.yml"

Minimum Django Applications

I make some assumptions about the packages that you'll use:

• django-postgrespool==0.2.4
• hiredis==0.1.1
• django-redis-cache==0.10.0

Running deployments

just a small example of things you can do :

playbook deployment/inventory/production all
playbook deployment/inventory/production webservers
playbook deployment/inventory/production dbservers
playbook deployment/inventory/production webservers --tags=pip

Testing deployments

• install virtualbox first
• edit inventory/vagrant to suit your desired scenerio
• get the machines created

$ pwd
/home/zenobius/Dev/websites/my-new-project/

$ cd deployment

$ ls -algh
total 4.0K
drwxrwxr-x 1 zenobius   56 Oct 23 08:57 .
drwxrwxr-x 1 zenobius   96 Oct 23 08:56 ..
drwxr-xr-x 1 zenobius   44 Oct 23 07:21 inventory
-rw-rw-rw- 1 zenobius 2.0K Oct 23 08:47 Vagrantfile

$ vagrant up
... snip hundreds of lines about creating virtualmachines ...

Then begin provisioning process

$ vagrant provision
... snip hundreds of lines about ansible playbook output ...

Using the playbook

• firstly, make sure your project directory layout matches the layout described below
• ensure you've followed the steps above in Installation.
• in your deployment directory :

For the entire infrastructure

$ playbook inventory/production site

To setup the database servers

$ playbook inventory/production dbservers

To run the tasks dealing with only installed/updating packages

$ playbook inventory/production appservers --tags=packages

Django Project Layout

In your django project, you should organise your settings module like so :

• git_root
  • deployment/
    • inventory
  • requirements/
    • base.list
    • live.list
    • test.list
    • local.list
  • application/
    • __init__.py
    • manage.py
    • base/
      • __init__.py
      • wsgi.py
      • settings/
        • modules/
          • __init__.py
        • __init__.py
        • default.py
        • local.py
        • live.py

project_root/manage.py

#!/usr/bin/env python
#
# file: project_root/manage.py
#
import os
import sys

if __name__ == "__main__":
    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "base.settings.local")
    from django.core.management import execute_from_command_line
    execute_from_command_line(sys.argv)

project_root/base/wsgi.py

import os
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "base.settings.live")
from django.core.wsgi import get_wsgi_application
application = get_wsgi_application()

project_root/base/settings/live.py

from .default import *
from .modules.db import *
from .modules.cache import *
from .modules.celery import *

DEBUG = False
TEMPLATE_DEBUG = DEBUG

...

project_root/base/settings/local.py

from .default import *


DEBUG = True
TEMPLATE_DEBUG = DEBUG

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': 'db.sqlite3',
    }
}
...