API Testing & Debugging

Introduction

No serious project is complete without testing. This lesson shows you how to write meaningful tests for your API, use debug tools, and create a developer-friendly error handling strategy.

Covered topics

• Manually testing routes in Postman (with edge cases)

• Writing unit and integration tests with a test runner

• Logging and inspecting request flows

• Handling async errors and displaying clean error messages

• Using logging middleware to capture bugs in dev

Why it matters

Testing prevents regressions and improves confidence in your code. Whether you're solo or working in a team, these habits lead to more stable, maintainable APIs.