23.3. API Gateway Integration with AWS Lambda: Creating Lambda Functions in Python

Creating Lambda functions in Python is an essential task when working with backend development on AWS. API Gateway integration with AWS Lambda allows developers to easily create, deploy, and manage APIs. This article will provide a detailed look at how to create Lambda functions in Python and integrate them with API Gateway.

Introduction to AWS Lambda

AWS Lambda is a compute service that lets you run 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 is not running.

Introduction to API Gateway

Amazon API Gateway is a fully managed service that makes it easy to develop, deploy, and maintain APIs at any scale. With API Gateway, you can create RESTful and WebSocket APIs that enable real-time connections for two-way data between applications and servers.

How to create Lambda functions in Python

To create a Lambda function in Python, you need to follow the following steps:

1. Open the AWS Lambda console and choose 'Create function'.
2. On the 'Create role' page, choose 'Author from scratch'.
3. Enter a name for your function, such as 'minhaFuncaoLambda'.
4. For 'Runtime', choose 'Python 3.8' (or whatever version of Python you want to use).
5. Under 'Permissions', choose 'Create a new function with basic Lambda permissions'.
6. Choose 'Create role'.

After you create the function, you can write the Python code in the 'Function Code' section of the AWS Lambda console.

How to integrate Lambda function with API Gateway

After you create your Lambda function, you can integrate it with API Gateway. Here are the steps you need to follow:

1. Open the AWS API Gateway console and choose 'Create API'.
2. On the 'Create new API' page, choose 'REST API' and then 'Build'.
3. Enter a name for your API and choose 'Create API'.
4. In the resources panel, choose 'Create method' and then 'POST'.
5. In the POST method configuration, for 'Integration', choose 'Lambda Function'.
6. Enter the name of your Lambda function and choose 'Save'.

After following these steps, your Lambda function will be integrated with API Gateway.

Conclusion

API Gateway integration with AWS Lambda allows developers to efficiently create and manage APIs. Creating Lambda functions in Python is a straightforward process that can be easily accomplished through the AWS Lambda console. Once the Lambda function is created, it can be integrated with API Gateway to enable the creation of RESTful and WebSocket APIs. This process allows developers to build scalable and efficient applications on AWS.