Amazon API Gateway
Developer Guide

What Is Amazon API Gateway?

Amazon API Gateway is an AWS service for creating, publishing, maintaining, monitoring, and securing REST and WebSocket APIs at any scale. API developers can create APIs that access AWS or other web services as well as data stored in the AWS Cloud. As an API Gateway API developer, you can create APIs for use in your own client applications (apps). Or you can make your APIs available to third-party app developers. For more information, see Who Uses API Gateway?.

API Gateway creates REST APIs that:

  • Are HTTP-based.

  • Adhere to the REST protocol, which enables stateless client-server communication.

  • Implement standard HTTP methods such as GET, POST, PUT, PATCH and DELETE.

For more information about API Gateway REST APIs, see Use API Gateway to Create REST APIs and Creating a REST API in Amazon API Gateway.

API Gateway creates WebSocket APIs that:

  • Adhere to the WebSocket protocol, which enables stateful, full-duplex communication between client and server.

  • Route incoming messages and based on message content.

For more information about API Gateway WebSocket APIs, see Use API Gateway to Create WebSocket APIs and About WebSocket APIs in API Gateway.

Architecture of API Gateway

The following diagram shows API Gateway architecture.


                API Gateway Architecture Diagram

This diagram illustrates how the APIs you build in Amazon API Gateway provide you or your developer customers with an integrated and consistent developer experience for building AWS serverless applications. API Gateway handles all the tasks involved in accepting and processing up to hundreds of thousands of concurrent API calls, including traffic management, authorization and access control, monitoring, and API version management. API Gateway acts as a "front door" for applications to access data, business logic, or functionality from your backend services, such as workloads running on Amazon Elastic Compute Cloud (Amazon EC2), code running on AWS Lambda, any web application, or real-time communication applications

Features of API Gateway

Amazon API Gateway offers features such as the following:

For a complete list of API Gateway feature releases, see Document History.

Accessing API Gateway

You can access Amazon API Gateway in the following ways:

Part of AWS Serverless Infrastructure

Together with AWS Lambda, API Gateway forms the app-facing part of the AWS serverless infrastructure. For an app to call publicly available AWS services, you can use Lambda to interact with required services and expose Lambda functions through API methods in API Gateway. AWS Lambda runs your code on a highly available computing infrastructure. It performs the necessary execution and administration of computing resources. To enable serverless applications, API Gateway supports streamlined proxy integrations with AWS Lambda and HTTP endpoints.

How to Get Started with Amazon API Gateway

For a quick introduction to Amazon API Gateway, see the following topics: