Integration testing

Overview

Integration testing helps you validate how different parts of your system work together—especially when services, modules, or third-party APIs depend on one another. This template gives you a head start on building and organizing tests to ensure that API workflows behave as expected when multiple components are involved.

It’s a useful pattern whether you’re validating internal service-to-service communication in a microservices setup or testing interactions with external systems.

What is integration testing?

Integration testing focuses on verifying that individual components of your system—such as services, modules, or API endpoints—interact correctly when combined.

In API development, that typically means testing multi-step workflows across endpoints, ensuring that the data flows and dependencies between services are consistent and reliable.

What does API integration testing involve?

At its core, API integration testing validates how different endpoints behave when they’re wired together. You're checking whether:

• Data flows from one request to another as expected

• Services respond correctly to upstream or downstream dependencies

• The end-to-end system behavior reflects real-world usage

It’s especially valuable when services are built and deployed independently—common in internal APIs and distributed systems—and you want to catch issues early, before they surface in staging or production.

What’s in the integration testing template?

This template includes test cases that simulate integrated workflows using the fictional Intergalactic Bank API. You can use it as a model for testing your own APIs across:

• Multiple internal services

• Interdependent modules

• Third-party integrations

Requests and test scripts are organized for clarity and easy modification, so you can adapt the structure to your own systems.

How to use the template

1. Explore the template: Fork it and read through the sample tests to understand how integrations are structured.

2. Run the examples: Execute the sample tests to see how interactions between endpoints are validated.

3. Customize for your API: Modify or extend the collection with your own endpoints, workflows, and data expectations.

4. Set up an environment: Use environment variables for base URLs, tokens, and test data to streamline execution across dev/staging/prod.

5. Debug failures: If a test fails, it usually means there’s a mismatch in the contract or an unexpected behavior downstream. Use this as a cue to investigate and refine.

6. And automate your integration testing when ready.