Stelligent

About

This project is to showcase knowledge in a programming language (Python), in Amazon Web Services and development techniques. Deploying this application will expose an API endpoint that can be queried to retrieve an ultra secret message and the current timestamp.

Prerequisites

• In order to run the script to build or destroy the application, python3.6 (or newer version) and boto3 must be installed.
• In order to successfully deploy the infrastructure to Amazon Web Services, an AWS Account with an IAM User that has programmatic access (Access Key ID and Secret Access Key ID) must be made available through the AWS credentials or config files, environment variables or passed into the scripts during run time.
• The IAM User must have sufficient access to create, update and delete the following types of AWS Resources:
  • IAM Roles
  • Security Groups
  • VPC, Subnet, Internet Gateway, NAT Gateway, Route Tables
  • Application Load Balancers and Target Groups
  • Launch Configurations and Auto Scaling Groups

Installation

Python3.6 and pip must be installed.

To install boto3, run the following:

sudo pip install boto3 botocore

The AWS Access Key ID and AWS Secret Access Key ID MUST be passed to the script unless it is stored in ~/.aws/credentials or ~/.aws/config files, or have it set as an environment variable. If the script cannot find valid credentials, it will notify and exit.

Clone the repository, or ensure that you have the app.cf, app.py, go.py, and requirements.txt downloaded to the same folder. To run the script:

cd /path/to/directory
python3 go.py build

Arguments

The following are arguments that the script will accept:

Argument	Default	Description
-i	null	The AWS Access Key ID
-s	null	The AWS Secret Access Key ID
-k	merickson-miniproject	The AWS EC2 Key Pair name. If it does not exist, script will create it
-r	us-east-1	The AWS Region
-n	merickson-miniproject	The CloudFormation stack name

Actions:

• build
• info
• test
• destroy

Examples

python3 setup.py build -n 'test-project' -k 'testing'
python3 setup.py build -i 'AKIAIOSFODNN7EXAMPLE' -s 'wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY' -r 'us-west-1'

Output

The go.py script will display the on-going progress of the build or destroy actions. Upon the completiong of the stack, the Message API URL and response will be displayed.

The VPC ID and Message API URL will also be displayed in the CloudFormation Stack's output tab.

AWS Infrastructure

The setup script will create a new CloudFormation Stack based on the app.cf file. This stack will do the following:

• Create a VPC
• Create and attach an internet gateway
• Create 2 public and 2 private subnets
• Create 2 NAT Gateways, one in each private subnet
• Create a public and 2 private route tables
• Add appropriate routes to use gateways
• Security groups with appropriate rules
• Application load balancer in public subnet
• Target group
• Launch configuration
• Auto scaling group in private subnets

Usage

Once the application has been deployed, the user can go to the application load balancer's dns name to view the message. The user can also curl, request or any other method of get to the URL to receive the message.

At the completion of the build action, the API URL will be displayed to the user, in addition to the response of the request of the URL.

Alternatively, the location of the application load balancer's dns name can be found by:

1. Going to the AWS Console
2. Selecting the EC2 service
3. Selecting the Load Balancers link
4. Selecting the appropriate load balancer
5. Viewing the Description tab
6. Retrieve the DNS name

Additionally, the user can get the parameters and outputs of the CloudFormation stack can be seen by using the scripts info action:

cd /path/to/directory
python3 go.py info

Lastly, the user can test the API URL and receive the response by using the test action of the script:

cd /path/to/directory
python3 go.py test

Uninstallation

To remove the application infrastructure from AWS, run the following command:

cd /path/to/directory
python3 go.py destroy

This destroy action of the script will remove the CloudFormation stack and delete the application files from the bucket. It will not delete the following:

• Key Pair (even if the setup script created it)
• The SSM Parameter used to store the Key Pair Material
• The KMS Key used to encrypt the SSM Parameter
• The bucket created to store the application files.

Arguments

The same arguments apply to the script's destroy action with the exception of the -k argument. Since the Key Pair is not deleted, the argument is not applicable.

Examples

python3 go.py destroy -n 'test-project' -k 'testing'
python3 go.py destroy -i 'AKIAIOSFODNN7EXAMPLE' -s 'wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY' -r 'us-west-1'

Testing

Unit testing has been written for each function within in each python file.

In order to run the test_app.py script, you must first install the application dependencies list in the requirements.txt file. You can run the following command to install them:

cd /path/to/dir
pip install -r requirements.txt

Then the tests can be run using the following commands:

cd /path/to/dir
python3 test_app.py
python3 test_go.py

These tests do not actually deploy anything, but instead test the logic of each function, mocking outside resources.