EC2 and Django

My configuration for micro ec2 django instances that will be serving mostly static content

Choosing EC2 AMI

I went with the latest Ubuntu Hardy image. I've used it in the past and it works fine:

ami-cb8d61a2

Amazon portal config:

1. Choose the image and click launch
2. Go through the wizard, choose micro instance and go through the defaults until you set up your private key.
3. Choose something meaningful to the server you're building. Create the private keypair (a .pem file), download it, and move it to your ~/.ssh directory.
4. For firewall, enable ssh and http access. I usually give it a group name like 'quick-start' For larger apps, you might want to enable more than just ssh and http, like mysql access, or smtp for mail service, etc.
5. Hit launch

Installing utils

We're ready to start installing things

ssh into your brand new ubuntu box on ec2:

ssh -i ~/.ssh/myprivatefile.pem ubuntu@ec2-##-##-##-###.compute-1.amazonaws.com

If you get a permission error, like this:

Permissionssions 0644 for '/Users/buf/.ssh/myprivatefile.pem' are too open.
It is recommended that your private key files are NOT accessible by others.
This private key will be ignored.
bad permissions: ignore key: /Users/buf/.ssh/myprivatefile.pem
Permission denied (publickey).m 0644 for '/Users/buf/.ssh/myprivatefile.pem' are too open.

I fixed this with writing the pem rules to 600:

chmod 600 ~/.ssh/myprivatefile.pem

After we've ssh'd in. Let's install django, python mysqldb, mysql server, and mod_wsgi:

sudo aptitude install python-django
sudo aptitude install mysql-server
sudo aptitude install python-mysqldb
sudo aptitude install libapache2-mod-wsgi

Setting up wsgi

Setting up bare bones django:

cd /usr/local
mkdir www
cd www
sudo apt-get install python-setuptools
sudo easy_install --upgrade django
django-admin startproject myproject

Make a new sites-available for your new django project:

sudo vim /etc/apache2/sites-available/myproject.com

Write standard sites config:

<VirtualHost *:80>
    ServerName myproject.com
    ServerAlias www.myproject.com
    WSGIScriptAlias / /usr/local/www/myproject/myproject.wsgi
</VirtualHost>

Make myproject.wsgi file:

vim /usr/locale/www/myproject/myproject.wsgi

Write standard myproject.wsgi file:

import os
import sys
sys.path.append('/usr/local/www')
sys.path.append('/usr/local/www/myproject/')

os.environ['DJANGO_SETTINGS_MODULE'] = 'myproject.settings'

import django.core.handlers.wsgi

application = django.core.handlers.wsgi.WSGIHandler()

Start it up

Enable the site in apache and reload:

sudo a2ensite mysite.com
sudo /etc/init.d/apache2 reload

Don't forget about your Elastic IPs

Back in the Amazon portal, you'll need to click on Elastic IPs and allocate a new address. Then click associate address and choose the instance that you've just set up. Now, with the newly assigned IP, paste it in your browser and:

It works!

Now would be a good time to set up your DNS with Amazon Route 53.

Brief Instructions:

1. Click Create hosted zone
2. Login to your registrar and copy the DNS entries Amazon gave you into your DNS nameservers
3. Back on AWS, click on the hosted zone you just created, click Create record set and type www into Name. Then make an A type record with a value of the same IP address as your Elastic IP. Click save.
4. Wait about 15 seconds

(Optional) Upgrade Python

I'm going to go with Python 2.7.3:

sudo apt-get install libreadline-dev
sudo apt-get install libsqlite3-dev
sudo apt-get install libbz2-dev
sudo apt-get install libssl-dev

Head on over to http://www.python.org/ and pick your favorite Python:

wget http://www.python.org/ftp/python/2.7.3/Python-2.7.3.tar.bz2
tar -xvjf Python-2.7.3.tar.bz2
cd Python-2.7.3.tar.bz2
./configure
make -j

If you get an error saying that no compatible C compiler could be found, you can always pick one GCC:

sudo apt-get install gcc

Also if you don't have make installed:

sudo apt-get make

After make does it's thing, just need to run:

sudo make install

which installs Python into /usr/local/bin. It will add a symlink to /usr/local/bin/Python2.7.3:

>$ python --version
>Python 2.7.3

(Optional) Install some python essentials

First, you'll need pip. But in order to get pip, you need either setuptools or distribute. I prefer distribute:

curl -O http://python-distribute.org/distribute_setup.py
sudo python distribute_setup.py

And now for pip:

curl -O http://pypi.python.org/packages/source/p/pip/pip-1.0.tar.gz
tar xvfz pip-1.0.tar.gz
cd pip-1.0
sudo python setup.py install

After that, you're home free.