In the field of cloud computing on AWS, API Gateway emerges as a powerful tool that empowers developers to conquer the challenges of building serverless applications with ease and efficiency. Serving as the gateway to your application's APIs, API Gateway enables seamless integration, powerful customization, and robust security. With its versatile features and capabilities, developers can effortlessly design, deploy, and scale APIs while focusing on delivering exceptional user experiences. In this article, we will embark on a voyage to explore AWS API Gateway in-depth, untangling its key features and showcasing how it acts as a catalyst for developers to embrace the realm of serverless architectures. I am going to try as much as I can to go straight to the point. So without wasting time, roll with me!
What is Amazon API Gateway?
Amazon API Gateway is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs at any scale. It is common knowledge that APIs act as the "front door" for applications to access data, business logic, or functionality from your backend services. With a few clicks in the AWS Management Console, you can use the API Gateway service to create an API that acts as an entry point for applications to access data, business logic, or functionality from your back-end services, such as applications running on Amazon EC2, ECS or AWS Elastic Beanstalk, code running on AWS Lambda, or any web application. API Gateway makes it easy to build and manage APIs at any scale, allowing developers to focus on writing the actual application code instead of dealing with infrastructure and low-level API management tasks. It offers a range of features such as request and response transformations, authorization and authentication mechanisms, traffic management, caching, and monitoring, empowering developers to build robust and secure APIs.
It is often said that "Why" is more important than "How" so before going on to see how to use API Gateway or its features and capabilities, let me talk about why you should use it in the first place. You should use API Gateway because it provides several key benefits for your API development and management process. Firstly, it offers a streamlined and scalable approach to building APIs, allowing you to quickly create, deploy, and manage them with ease. It also provides essential security features such as authentication, authorization, and access control, ensuring that your APIs are protected from unauthorized access. Additionally, API Gateway enables you to handle complex traffic management, including rate limiting, caching, and throttling, to ensure optimal performance and availability of your APIs. API Gateway seamlessly integrates with other AWS services, enabling you to leverage the full power of the AWS ecosystem in your API development and delivery.
Now, we can start answering the How questions beginning by looking at how API Gateway works.
How does API Gateway work?
They say a picture is worth a thousand words so instead of talking at length about how Amazon API Gateway works, I'll just show you a picture that visually explains it.
API types supported by API Gateway
Amazon API Gateway offers two options to create RESTful APIs, HTTP APIs and REST APIs, as well as an option to create WebSocket APIs. API Gateway's support for various API types provides flexibility to suit different use cases. Let's explore these API options or types briefly one after the other.
REST APIs — They are widely used for building web services. API Gateway allows you to define and manage RESTful APIs, supporting HTTP methods like GET, POST, PUT, DELETE, etc. It leverages the RESTful principles for resource-based interactions.
HTTP APIs — They provide a simplified, cost-effective way to build APIs with reduced overhead. HTTP APIs offer enhanced performance, lower latency, and native support for popular features like CORS (Cross-Origin Resource Sharing) and JWT (JSON Web Tokens) authorizers.
WebSocket APIs — WebSocket APIs maintain a persistent connection between connected clients to enable real-time message communication. With WebSocket APIs in API Gateway, you can define backend integrations with AWS Lambda functions, Amazon Kinesis, or any HTTP endpoint to be invoked when messages are received from the connected clients.
I'll like us to turn our focus to talk about two advanced features of Amazon API Gateway; Throttling and Caching.
Throttling
Throttling in Amazon API Gateway can be thought of as a traffic regulator for your APIs. It's like having a traffic cop on a busy road who controls the flow of vehicles to prevent congestion and maintain a smooth traffic flow. Similarly, throttling helps manage the flow of API requests, ensuring that your system doesn't get overwhelmed by a sudden surge of requests. It is basically a mechanism that controls the rate at which API requests are processed. It allows you to limit the number of requests per second or minute to your APIs, preventing system overload and ensuring fair usage of resources. Throttling helps maintain system stability, protect against abuse or excessive traffic, and manage API performance. In API Gateway, you can configure throttling settings at multiple levels, including the API level, stage level, or individual method level. You can set the desired rate limits for different types of requests, such as read and write operations and define burst limits to handle short-term spikes in traffic. When a request exceeds the configured throttling limits, API Gateway responds with a 429 HTTP status code, indicating that the request has been throttled. Throttled requests can be retried after a certain period or with a back-off strategy. Throttling provides you with granular control over API traffic and helps ensure the reliability and availability of your APIs. It allows you to balance the load on your backend systems, protect against sudden surges in traffic, and provide a consistent experience to your API consumers.
Caching
Caching allows you to store and reuse API responses, improving performance and reducing the load on your backend systems. When you enable caching, API Gateway stores the response of a request and associates it with a unique identifier. Subsequent requests with the same parameters can be served directly from the cache, without the need to execute the backend process again. Caching is beneficial for scenarios where you have data or responses that don't change frequently and are shared across multiple requests. By storing the response in the cache, API Gateway can quickly serve it to subsequent requests, reducing the overall latency and improving the responsiveness of your APIs. This is particularly useful for read-heavy workloads or data that remains static for a certain period of time. It's important to consider the nature of your data and API requirements before implementing caching. Caching is most effective for static or semi-static content and may not be suitable for real-time data or dynamic information that needs to be up-to-date with each request.
Final Thoughts
By serving as a front door to your backend services, API Gateway provides a seamless way to expose and manage APIs at scale. With its robust features such as request and response transformations, authentication and authorization mechanisms, caching, and throttling, API Gateway simplifies the process of building, deploying, and securing serverless APIs. It allows developers to focus on their core application logic while abstracting away the complexities of infrastructure management. Whether you're building microservices, mobile backends, or integrating with third-party services, API Gateway provides the foundation for creating scalable and reliable serverless architectures. By leveraging the capabilities of API Gateway, developers can accelerate their development cycles, improve the performance of their applications, and deliver exceptional experiences to their users. It's an essential component in the AWS ecosystem for building modern serverless applications.