What is Integration Testing?
Integration Testing involves testing combined modules as a group. It identifies defects in interactions between integrated components and validates the overall system behavior.
Objectives of Integration Testing
- Verify data flow between integrated modules
- Detect interface and communication errors
- Validate overall system behavior
Advantages
- Ensures modules interact correctly
- Detects defects missed in Unit Testing
- Improves overall software reliability
Limitations
- Time-consuming with large systems
- Requires proper planning of test data
- May miss deeper logic-level issues
Integration Testing Process
- Identify modules to integrate.
- Define test strategy (Big Bang, Top-Down, Bottom-Up, or Hybrid).
- Prepare integration test cases and data.
- Execute tests and observe results.
- Fix defects and re-test.
️ Example
Example: Testing the integration between the Shopping Cart module and the Payment Gateway module in an e-commerce application is Integration Testing.
️ Popular Tools
- JUnit + Mockito (Java)
- TestNG (Java)
- Postman (API Integration)
- Selenium (Web-based integration)
- SOAP UI (Web Services)
Best Practices
- Plan integration tests early in the SDLC.
- Use stubs and drivers when modules are unavailable.
- Automate integration tests for regression coverage.
- Ensure proper error handling across modules.
