📖 What is Amazon API Gateway?
Amazon API Gateway is a fully managed service enabling developers to create, publish, maintain, monitor, and secure APIs at any scale. It handles tasks like authentication, authorization, request validation, and traffic management, simplifying API development and deployment for microservices and serverless applications.
"API Gateway is a critical component of serverless architectures, often acting as the entry point for Lambda functions. Be prepared to differentiate between REST APIs, HTTP APIs, and WebSocket APIs, understanding their respective use cases and cost profiles."
📚 Certification: AWS Certified Solutions Architect - Associate (SAA-C03)
🔑 What are the Key Concepts of Amazon API Gateway?
- ▸ API Gateway acts as a reverse proxy, shielding backend services (like Lambda) from direct internet exposure and managing traffic flow.
- ▸ Different API types (REST, HTTP, WebSocket) offer varying features and cost structures; choose based on application requirements.
- ▸ Stages allow for managing different versions of your API (dev, test, prod) and controlling deployments without impacting live traffic.
- ▸ Integration types determine how API Gateway connects to backends – Lambda, HTTP, Mock, or AWS Service integrations are common.
- ▸ Throttling and caching features enhance API performance, security, and cost-effectiveness by managing request rates and reducing backend load.
🎯 How does Amazon API Gateway appear on the SAA-C03 Exam?
You may be asked to identify the best service to front a serverless application built with Lambda functions, handling authentication and request routing.
A scenario might describe a need to build a real-time chat application – determine which API Gateway type (WebSocket) is most appropriate.
Expect questions about configuring API Gateway to integrate with a DynamoDB backend, including request/response transformations and data mapping.
❓ Frequently Asked Questions
When should I use HTTP APIs versus REST APIs?
HTTP APIs are generally more cost-effective for simple proxy integrations, while REST APIs offer more features like request validation and transformation, suitable for complex scenarios.
How can I secure my APIs using API Gateway?
API Gateway supports various security mechanisms, including IAM roles, Cognito authorizers, and custom authorizers (Lambda functions) to control access and authenticate users.
What is the purpose of usage plans and API keys?
Usage plans allow you to control how much an API can be used by a specific API key, enabling you to offer different tiers of service or restrict access for billing purposes.