what is integration test
An integration test is a software test that checks whether different modules, services, or components work correctly when connected together. It focuses on the interactions and data flow between parts, not just whether each part works on its own.
Quick Scoop
Integration testing is useful when you want to catch problems at the boundaries between parts of a system, such as API calls, database connections, or module communication. For example, a login form might work in isolation, but an integration test would verify that the form, authentication service, and database all work together correctly.
Why it matters
- It helps find interface mismatches early.
- It verifies that data moves correctly between components.
- It reduces surprises before system-wide or end-to-end testing.
Simple definition
Integration testing = testing how parts of an app work together after they are combined.
Tiny example
If you have:
- A frontend checkout page.
- A payment service.
- An order database.
An integration test checks that placing an order on the frontend actually triggers payment processing and stores the order correctly.
If you want, I can also explain the difference between unit test, integration test, and end-to-end test.