Deploying a Django app on AWS

Overview

All of these steps are performed locally.

Prerequisites

I didn't realize this at first, but these prerequisites are all local. The first time I tried this out, I thought I had to get on a remote server to install Python, Django, awsebcli, etc. All of these things are installed on the local workstation and eb deploy handles moving them over and replicating the app environment.

• EB CLI

$ brew install awsebcli

• See AWS Services
• See Django App Prerequisites for AWS Elastic Beanstalk

AWS Elastic Beanstalk

Existing Elastic Beanstalk applications and environments can be found in the AWS Elastic Beanstalk management console.

Create a new Elastic Beanstalk application from the command line on a local workstation:

$ eb init

This will prompt for region, credentials, application name, python version, ssh availability, etc.

These properties are stored in .elasticbeanstalk/config.yml which should not be added to Git.

Create a new Elastic Beanstalk environment from the command line on a local workstation. Assuming that the instance is using an independent RDS.

$ eb create

If instead the Elastic Beanstalk environment is creating its own database, it's necessary to specify that option with the create command:

$ eb create --database.engine postgres

This will prompt for the environment name, its URL prefix, and a database username and password.

Saving and applying Elastic Beanstalk environment configuration

Elastic Beanstalk environment configuration is controlled through the Configuration panel of the AWS Elastic Beanstalk console.

For example, it's necessary to configure Security Groups and Environment Variables to support connecting to independent RDS instances.

To save an environment's configuration to apply again later if an environment is created from scratch, save the environment configuration.

From the AWS EB console: select application > select environment > Actions button at the upper right > Save Configuration

From the eb cli: eb save environment-name. This will save the configuration under .elasticbeanstalk/saved_configs/env-name-version.cfg.yml

To apply a saved configuration to an Elastic Beanstalk environment:

AWS EB console > select application > select environment > Actions button at the upper right > Load Configuration

Deploying a Django app

Updates to the app are deployed with eb deploy.

This looks at .elasticbeanstalk/config.yml for the target application and environment.

branch-defaults:
  master:
    environment: nrose-env
global:
  application_name: north-rose
  default_ec2_keyname: nrosedevs-aws
  default_platform: 64bit Amazon Linux 2015.09 v2.0.6 running Python 3.4
  default_region: us-west-2
  profile: eb-cli
  sc: git

With the master Git branch checked out, and the config.yml above, eb deploy will package up the project file and upload them to the EC2 instance corresponding with the nrose-env environment of the north-rose app.

To update a staging environment, edit config.yml with the following:

branch-defaults:
  master:
    environment: nrose-env
  staging:
    environment: nrose-staging
  staging-nodebug:
    environment: nrose-staging

With the staging Git branch checked out, eb deploy will now update the nrose-staging environment.

Alternatively, use eb deploy alternate-env to target a non-default EB environment named alternate-env.

Installing Django app dependencies

See Defining Django App Dependencies

See also Customizing AWS Software With .ebextensions

Production environment project settings

Set DEBUG to False:

# myapp/settings.py
# ...
DEBUG = False

With DEBUG = False, ALLOWED_HOSTS is required.

Add localhost, the domain of the site, Elastic Beanstalk, and AWS's Elastic Load Balancer to ALLOWED_HOSTS:

# myapp/settings.py
# ...
DEBUG = False

ALLOWED_HOSTS = [
    "localhost",
    "mydomain.com",
    ".us-west-2.elasticbeanstalk.com",
    ".compute-1.amazonaws.com" # allow viewing of instances directly
]

# Grant access to AWS's Elastic Load Balancer
import requests
EC2_PRIVATE_IP = None
try:
    EC2_PRIVATE_IP = requests.get('http://169.254.169.254/latest/meta-data/local-ipv4', timeout=0.01).text
except requests.exceptions.RequestException:
    pass

if EC2_PRIVATE_IP:
    ALLOWED_HOSTS.append(EC2_PRIVATE_IP)

It's necessary to install python-requests for the above code. (pip install requests).

Configuring an independent RDS instance

See Using Elastic Beanstalk With Amazon RDS

Run makemigration locally. This prevents potential data loss on the production server.
eb deploy will move the migrations file to the EC2 instance and have them ready to run a migrate.

$ python manage.py makemigrations

• Add a .config command to run the migration; it will run as part of the eb deploy process.
• Deploy the project using eb create or eb deploy.

Creating an admin account

See Creating a Django Admin Account on Elastic Beanstalk

Serving static files using Amazon S3

Configuration

See Configuring Django to Serve Media Files Via S3

Deployment

Once configured to use S3 for storage, Django's collectstatic command will upload static files to the S3 bucket. Both the AWS servers and local development will reference the files on S3.

This means that if a stylesheet is compiled, the collectstatic command must be run before the changes are available anywhere.

python manage.py collectstatic --noinput

The --noinput flag simply bypasses any confirmation messages.

The static template tag will correctly reference static resources in the Amazon S3 bucket.

Timestamps don't always correspond between S3 and the local filesystem. In some cases a newly edited file won't register as changed based on its timestamp. In these cases log into the AWS Management Console, navigate to the bucket under S3 and manually delete the file before executing manage.py.

Managing domain names

The documentation at Your Elastic Beanstalk Environment's Domain Name (AWS Elastic Beanstalk Developer Guide) is straight forward and easy to follow.

See Managing Elastic Beanstalk Domain Names

Security Certificates

See EC2 Security Certificates for how to install and manage security certificates for Elastic Beanstalk hosted sites.

Notes

See also

• Deploying a Django Application - AWS Elastic Beanstalk documentation
• Deploying a Django app to AWS Elastic Beanstalk - Real Python (Jan. 22, 2015)
• Django and Amazon AWS Elastic Beanstalk with S3 - Racing Tadpole, June 15, 2013
  Some information about using S3 for a file system.)
• How to Make Django's ALLOWED_HOSTS work with AWS ELB Health Checks - Dryan, Jan 5, 2014