In Chapter 24.3, we'll explore developing REST APIs with API Gateway and Lambda, with an introduction to AWS Lambda. REST APIs are a popular way to create services that can be consumed across the web. AWS provides a robust and scalable way to create and manage these APIs using API Gateway and AWS Lambda.
AWS Lambda is a serverless computing service that lets you run your code without provisioning or managing servers. It runs your code only when needed and automatically scales from a few requests per day to thousands per second. You only pay for the computing time you consume - there are no charges when your code isn't running. With Lambda, you can run code for virtually any type of application or backend service, all without the need for administration. Just write the code and upload it to Lambda.
On the other hand, Amazon API Gateway is a fully managed service that makes it easy to develop, deploy, and maintain APIs at scale. API Gateway acts as a "gateway" for applications that access data, business logic, or functionality from your backends, such as code running on AWS Lambda, web applications, or real-time backend services.
By combining these two powerful services, we can develop high-performance and easy-to-maintain REST APIs. Let's start with an introduction to AWS Lambda.
Introduction to AWS Lambda
AWS Lambda is a service that lets you run your code without provisioning or managing servers. It takes care of everything needed to run and scale your code with high availability. You can configure your code to be automatically triggered from other AWS services or call it directly from any web or mobile application.
With AWS Lambda, you can focus on writing code, not managing infrastructure. This is especially useful for projects that need to scale quickly or that have unpredictable traffic patterns.
Additionally, AWS Lambda supports code written in Python, a programming language popular among developers due to its clear and concise syntax. This makes AWS Lambda an ideal option for developing REST APIs, as Python has a wide range of libraries to handle HTTP requests and common data formats used in REST APIs, such as JSON.
Development of REST APIs with API Gateway and Lambda
Developing a REST API with API Gateway and Lambda involves several steps. First, you need to define your API resources and methods in API Gateway. Then you need to write the code that will run when these methods are called, and upload that code to AWS Lambda.
First, you define your API resources in API Gateway. A resource is an entity that can be accessed through a URL. For example, in an API for a blog, you might have features for posts and comments. For each resource, you define methods, which are the actions that can be performed on that resource. For example, you can allow users to create, read, update, and delete posts.
After you define your resources and methods, you need to write the code that will run when those methods are called. This is the code you will upload to AWS Lambda. This code must be written in a language supported by AWS Lambda, which includes Python.
Finally, you configure API Gateway to trigger your Lambda code when your API methods are called. This is done by creating an integration between API Gateway and Lambda.
In summary, developing REST APIs with API Gateway and Lambda is a powerful and flexible process. You can define your API granularly in API Gateway and write highly customized code to handle requests in Lambda. And with Lambda's automatic scaling, your API can handle any amount of traffic.
We hope you're eager to learn more about AWS Lambda and how it can be used to build REST APIs with API Gateway. In the next chapter, we'll dive deeper into the process of developing REST APIs with API Gateway and Lambda, including code examples and best practices.
