Introduction to Docker, and a step by step guide to develop and deploy a Django app on AWS.

1. Tamer M Abdul-Radi @tabdulradi
Eslam ElHusseiny @EslamElHusseiny
https://github.com/kiosk12

2. Agenda
• Pain - What/Why Docker
• Developing and deploying a Django App
• How Docker works

3. –Every developer
“But it works on my machine.”

4. Django ? ? ? ? ?
PostgreSQL ? ? ? ? ?
Redis ? ? ? ? ?
Hadoop ? ? ? ? ?
Message Queue ? ? ? ? ?
Developer
Laptop
QA
Laptop
Staging
Server
Production
Server
Cloud
Matrix from Hell

5. (Pain) = n * m
• Every developer wastes almost a day to configure
his machine
• What about tester’s machine?
• Hot patches during release nights!
n = size of team + staging + production
m = size of project

9. Matrix from Hell!
Django ? ? ? ?
PostgreSQL ? ? ? ? ?
Redis ? ? ? ? ?
Big Data ? ? ? ? ?
Message Queue ? ? ? ? ?
Developer
Laptop
QA
Laptop
Staging
Server
Prod. on
Server
Prod. on
Cloud

10. Code time!
Let’s get our hands dirty

11. Installation
$ sudo apt-get install docker.io
$ sudo pip install -U fig
For OSX and Windows: check “boot2docker”

12. Create Dockerfile
FROM python:2.7
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
ADD requirements.txt /code/
RUN pip install -r requirements.txt
ADD . /code/

13. Create requirements.txt
django
psycopg2

14. Create fig.yml
db:
image: postgres
web:
build: .
command: python manage.py runserverv 0.0.0.0:8000
volumes:
- ./code
ports:
- “8000:8000”
links:
- db

15. Start Django project
$ fig run web django-admin.py startproject example .
$ ls
Dockerfile example fig.yml manage.py
requirements.txt
$ ls example
__init__.py settings.py urls.py wsgi.py

16. Configure Django App
DATABASES = {
‘default’: {
‘ENGINE’: ‘django.db.backends.postgresql_psycopg2’,
‘NAME’: ‘postgres’,
‘USER’: ‘postgres’,
‘HOST’: ‘db’,
‘PORT’: 5432
}
}

17. Run the app
$ fig up

18. In your browser

19. Access containers
$ fig run web ping db
$ fig run web cat /etc/hosts

20. Polls App
• Lets’s steal the polls app from official django tutorial
• https://docs.djangoproject.com/en/1.7/intro/tutorial01/
• Don’t forget to add polls to installed apps
$ fig run web python manage.py startapp polls

21. polls/models.py
from django.db import models
class Question(models.Model):
question_text = models.CharField(max_length=200)
pub_date = models.DateTimeField('date published')
class Choice(models.Model):
question = models.ForeignKey(Question)
choice_text = models.CharField(max_length=200)
votes = models.IntegerField(default=0)

22. polls/admin.py
from django.contrib import admin
from polls.models import Question
admin.site.register(Question)

23. Polls App
$ fig run web python manage.py makemigrations polls
$ fig run web python manage.py sqlmigrate polls 0001
$ fig run web python manage.py sqlmigrate polls 0001

24. Running the app
#!/bin/sh
python manage.py migrate
python manage.py runserver 0.0.0.0:8000
• Running the app became a bit more complex
• We need to make sure that models are migrated
• create run_web.sh

25. Update fig.yml
db:
image: postgres
web:
build: .
command: ./run_web.sh
volumes:
- ./code
ports:
- “8000:8000”
links:
- db

26. Create admin account
$ fig run web python manage.py createsuperuser

27. In your browser

28. Deploy time!

29. Fig for production
db:
image: postgres
web:
build: .
command: ./run_web.sh
volumes:
- ./code
ports:
- “80:8000”
links:
- db

30. Create Amazon Machine
aws ec2 run-instances
—image-id ami-234ecc54
—security-groups default
—instance-type c4.large
—key-name kiosk12

31. Configure Amazon Machine
• sudo apt-get install docker.io
• sudo pip install -U fig

32. Run
• -d = Daemon mode
• -f = Specify fig file
$ fig up -d -f fig-production.yml

33. Docker Internals
• Images
• Read-only templates
• Clone of the system with installed apps + code
• Containers
• Running instance of an image
• Isolated file system and ports
• Registeres
• Host for Images
• Dockerhub,com

34. Containers vs VM

35. Architecture

36. New Docker Features

37. Docker Machine
$ docker-machine create -d virtualbox dev
$ docker-machine create -d digitalocean --
digitalocean-access-token=... staging
$ docker-machine ls
NAME ACTIVE DRIVER STATE URL
dev virtualbox Running tcp://192.168.99.108:2376
staging * digitalocean Running tcp://104.236.37.134:2376

38. Docker Swarm
• Clustering for Dockerized distributed apps
• Selects a docker demon for your containers
(created by Docker machine)

39. Docker Compose
• Docker bought fig!
• No need to install two tools in future
• Almost same yaml syntax

40. Fun with Docker
• Explore dockerized apps at dockerhub.com with no
installation hassle!
• docker run mongo
• docker run --rm -v "$PWD" -p 4000:4000 grahamc/jekyll
• docker run -it --rm williamyeh/scala
• Some cool aliases here: http://github.com/tabdulradi/
docker-fish-functions

41. Tamer M Abdul-Radi
Software Engineer
twitter.com/tabdulradi
github.com/tabdulradi
abdulradi.com
Thanks
Eslam ElHusseiny
Systems Engineer
twitter.com/EslamElHusseiny
github.com/EslamElHusseiny
eslamelhusseiny.wordpress.com
http://github.com/Kiosk12/docker-django-demo