fourTheorem / application-composer-quotes-api-demo

application-composer-quotes-api-demo

This is a demo repository for a simple API service that returns motivational quotes. The entire service has been composed using AWS Application Composer and is deployed using AWS SAM.

Architecture

API

The API has a single endpoint that returns the latest ingested quote from the database along with the ingestion timestamp. The endpoint is available at https://<api-id>.execute-api.<region>.amazonaws.com/Prod/get-latest-quote

The response is a JSON object with the following structure:

{
    "quote": "The best way to predict the future is to create it.",
    "timestamp": "1681665388454"
}

Ingestion

The ingestion process is triggered by an EventBridge rule that is scheduled to run every 1 minute. It triggers a Lambda function that fetches a random quote from a static list of quotes and inserts it into a DynamoDB table.

Deployment

The service can be deployed using the following command:

cd src/api && npm ci
cd src/ingestion && npm ci
cd ../..

sam build
sam deploy --guided

Stack overview

• TypeScript
• AWS SAM
• AWS CloudFormation
• AWS API Gateway
• AWS DynamoDB
• AWS Lambda (nodejs18.x)
• AWS EventBridge
• AWS CloudWatch