Guide to Serverless & Lambda Testing - Testing Pyramid

In this post, the author discusses testing Serverless applications with a focus on Lambda functions. The Serverless Testing Pyramid is introduced with four levels of tests: unit, infrastructure, integration, and end-to-end (E2E). Each test type has its purpose and characteristics, and they all contribute to ensuring the overall quality of the Serverless application.

Unit tests focus on the functionality of individual units of code and are quick, isolated, and do not require deployment to AWS.

Infrastructure tests validate the configuration of resources before deployment and check for missing resources, logical ID changes, and security issues.

Integration tests, which make up the majority of the service tests, test the code's interaction with the deployed infrastructure on AWS. These tests typically run locally in the IDE and can call AWS services APIs and resources.

Lastly, E2E tests verify the entire system's functionality, testing from the user interface down to the database.

The author provides tips and code examples for each test type and shares a complimentary Serverless service project that utilizes best practices in testing.