README.md

AWS SAM Simple App

This is a simple fullstack application that deploys a Lambda function with the help of AWS Serverless Application Model (SAM) and a static webpage hosted on S3 that is able to send requests to the Lambda function

.
├── README.md                   <-- This instructions file
├── requirements.txt            <-- Python requirements file
├── frontend.py                 <-- Python function for creating frontend template
├── manage.py                   <-- Main Driver for this application
├── interview_functions         <-- Source code for lambda functions
│   ├── __init__.py
│   ├── ackermann.py            <-- Lambda function for the Ackermann function
│   ├── factorial.py            <-- Lambda function for the factorial function
│   ├── fib.py                  <-- Lambda function for the fibonacci function
├── template.yaml               <-- SAM Template
└── tests                       <-- Unit tests
    └── unit
        ├── __init__.py
        └── test_handlers.py

Requirements

• AWS CLI
• Python 3.6
• Docker
• AWS SAM
• Requirements listed in requirements.txt (pip install -r requirements.txt)

Running the application

You can view my own hosted solution here: http://testbucketashwin01.s3-website.eu-central-1.amazonaws.com/

Running locally

python manage.py

Using SAM, the application is packaged and deployed to localhost:3000. A html file is constructed and opened in your browser that is able to send requests to the application.

Example endpoints you can try:

• http://localhost:3000/factorial/4

Deploying to S3

Prerequisites

• An existing public S3 bucket in eu-central-1 Your bucket policy should look like this (replace bucket name with your own)

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "PublicReadForGetBucketObjects",
            "Effect": "Allow",
            "Principal": "*",
            "Action": "s3:GetObject",
            "Resource": "arn:aws:s3:::testbucketashwin01/*"
        }
    ]
}

Deploying the application

• The script takes a parameter for the s3 bucket called bucket-name and can be run as shown below:

python manage.py --bucket-name testbucketashwin01

Tests

Pytest is used to run tests. To run it, navigate to the tests folder and run the following command:

    export PYTHONPATH='../' && pytest

Cleanup

aws cloudformation delete-stack --stack-name ashwin-app