API HTTP versus API REST

Welcome! AWS API Gateway is crucial for serverless apps. It acts as the "front door" for your backend services. But which type of API should you use?

This lesson will compare REST APIs and HTTP APIs. You'll learn their unique strengths and weaknesses to help you choose the best fit for your serverless backend.

AWS REST APIs are the original and most feature-rich type offered by API Gateway. They're built on the REST architectural style and provide robust control.

Think of them as a comprehensive toolkit for managing complex API interactions and integrations.

REST APIs offer advanced features for fine-grained control:

• Request/Response Mapping: Transform payloads using Velocity Template Language (VTL).
• Custom Authorizers: Implement Lambda-based or Cognito user pool for flexible auth.
• Usage Plans & Throttling: Manage API access, rate limits, and quotas for clients.
• AWS WAF Integration: Protect your APIs from common web exploits.
• Edge Optimization: Global endpoint with CloudFront distribution for lower latency.

Opt for REST APIs when your project demands extensive customization, advanced security, or complex integrations:

• You need to transform data formats between client and backend.
• You require granular access control with custom authentication logic.
• You need to monetize or meter API usage with detailed plans.
• Integrating with legacy systems that require specific payload structures.

HTTP APIs are a newer, lighter, and more cost-effective alternative. They are designed for high performance and simplicity, especially for modern serverless workloads.

They act as a straightforward proxy for your backend services, focusing on speed and efficiency.

HTTP APIs streamline the API Gateway experience:

• Lower Latency: Generally faster request processing compared to REST APIs.
• Reduced Cost: Significantly cheaper per request, making them very economical.
• Direct Integrations: Seamlessly connect to Lambda functions and other HTTP endpoints.
• Built-in JWT Authorizers: Easy integration with OIDC and OAuth 2.0 providers.
• CORS Support: Simple configuration for Cross-Origin Resource Sharing.

Choose HTTP APIs when performance, cost-efficiency, and straightforward integrations are your main priorities:

• Building a simple, fast API proxy for Lambda functions.
• Developing cost-sensitive serverless applications.
• You only need basic JWT-based authentication.
• Integrating with HTTP backends without complex data transformations.

Let's summarize the key distinctions:

• Performance: HTTP APIs are faster with lower latency.
• Cost: HTTP APIs are significantly more affordable.
• Feature Set: REST APIs offer more advanced features (VTL, WAF, custom authorizers).
• Complexity: HTTP APIs are simpler to configure and manage.
• Use Cases: REST for complex, HTTP for simpler/high-performance.

You've learned about the differences between REST and HTTP APIs. Now, let's test your knowledge!

Great job! You now understand the core differences between AWS API Gateway's REST APIs and HTTP APIs.

Remember to consider your project's needs for performance, cost, and feature complexity when deciding which API type is best. Both are powerful tools in your serverless toolkit!