What is Amazon API Gateway? - Amazon API Gateway
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What is Amazon API Gateway?

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

API Gateway creates RESTful APIs that:

  • Are HTTP-based.

  • Enable stateless client-server communication.

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

For more information about API Gateway REST APIs and HTTP APIs, see Choosing between REST APIs and HTTP APIs, Working with HTTP APIs, 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 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.

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 Amazon serverless applications. API Gateway handles all the tasks involved in accepting and processing up to hundreds of thousands of concurrent API calls. These tasks include 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 Amazon 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 Amazon serverless infrastructure

Together with Amazon Lambda, API Gateway forms the app-facing part of the Amazon serverless infrastructure.

For an app to call publicly available Amazon services, you can use Lambda to interact with required services and expose Lambda functions through API methods in API Gateway. Amazon 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 Amazon Lambda and HTTP endpoints.

How to get started with Amazon API Gateway

For an introduction to Amazon API Gateway, see the following: