AWS API Gateway for Developers

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Arjit Sharma
02 Mins

When building backend services, you need a secure, scalable, and manageable way to expose them to clients. That’s where API Gateway comes in - your gateway to the cloud.

What Is API Gateway?

AWS API Gateway is a fully managed service that enables developers to build, publish, and manage RESTful or HTTP APIs. It acts as a front door for your backend services, routing requests to AWS Lambda functions, EC2 instances, or other AWS services.

When to Use API Gateway:

  • Exposing RESTful APIs for your application
  • Handling API rate limiting and throttling
  • Easy versioning and deployment of APIs

How API Gateway Works

API Gateway acts as a proxy that receives HTTP requests from clients and routes them to the appropriate backend service.

  1. Request Handling: The client sends a request (e.g., POST /api/users).
  2. Routing Traffic: API Gateway routes the request to the appropriate backend (Lambda, EC2, etc.).
  3. Response Handling: It optionally transforms the response and returns it to the client.
  4. Scaling: API Gateway scales automatically to handle millions of requests per second.

Key Concepts in API Gateway (Quick Reference)

ConceptDescription
APIEntry point for clients to access services
ResourceURL path (e.g., /users, /products).
MethodThe type of HTTP request (GET, POST, etc.) for a resource.
IntegrationBackend connected to the method
StageA version of the API deployed for use (e.g., dev, prod).
Throttling & Rate LimitingControls the number of requests clients can make in a given period.

Setting Up a Simple REST API

Step 1: Create an API

  1. Go to API Gateway → Create API.
  2. Choose REST API or HTTP API.
  3. Define the API Name and Description.

Step 2: Define Resources and Methods

  1. Create a new Resource (e.g., /users).
  2. Define the HTTP Method (e.g., GET, POST, PUT).
  3. Connect methods to a backend (e.g., Lambda, DynamoDB, or HTTP endpoints).

Step 3: Deploy the API

  1. Create a Stage (e.g., dev, prod).
  2. Deploy the API to the stage, which gives you a public URL.