Architecture deployed on Amazon Web Services
A serverless REST API using AWS consists of Amazon API Gateway handling incoming HTTP requests and routing them to AWS Lambda functions, which contain the business logic and execute code in response to each request without the need to manage servers.
These Lambda functions interact with a PostgreSQL database hosted on Amazon RDS, allowing the API to perform CRUD operations on persistent data. API Gateway manages endpoint routing, throttling, and authorization, while Lambda ensures automatic scaling and pay-per-use pricing, making the architecture highly scalable and cost-efficient for modern cloud-native applications.
Deployment using AWS Chalice
AWS Chalice is a Python framework that makes it easy to build and deploy serverless REST APIs using AWS Lambda and API Gateway. By defining routes in a simple app.py file, developers can create endpoints that automatically deploy to Lambda and are exposed via API Gateway without manual configuration.
from chalice import Chalice
app = Chalice(app_name='api')
@app.route('/user')
def user():
return {'message': 'Hello from user!'}Chalice handles packaging, IAM roles, and stage environments, and supports environment variables for securely connecting to services like an RDS PostgreSQL database. With a single chalice deploy command, you can launch a fully functional API accessible over the web.
Securing the serverless REST API
The security of a serverless REST API built with AWS Chalice, Lambda, API Gateway, and RDS is reinforced through multiple layers:
- API Gateway must enforce authentication and authorization using AWS IAM or Amazon Cognito, ensuring that only trusted clients can access the endpoints.
- Lambda functions are deployed inside a Virtual Private Cloud (VPC) to securely connect to the RDS PostgreSQL instance without exposing the database to the public internet.
- Security groups and subnet configurations further restrict network access to only necessary resources, particularly the RDS PostgreSQL database.
- Environment variables are used to manage sensitive credentials securely, and AWS IAM roles control the exact permissions each Lambda function has, following the principle of least privilege.
Combined, these measures provide a robust and secure architecture for cloud-native applications.