Integration testing: Definition, Importance, strategies/approaches
This article will present you with a complete idea about integration testing definition, strategies , importance etc.
We will learn below topics in this article
What is Integration Testing?
It is a type of testing to check if different modules work together as a whole.The purpose is to find faults in the interaction between integrated units.
- Main traditional strategies can be classified as top-down integration, bottom-up integration, big-bang integration.
- We reconsider these strategies in an object-oriented environment.
- Various factors like cost, complexity of the application etc determine which approach is selected.
The purpose is to expose faults in the interaction between integrated units. Once all the modules have been unit tested, integration testing is performed.
It is second level of testing performed after Unit Testing and before System Testing.Interaction between integrated components is called Component Integration testing.
For more on definition refer link.
Importance:
- Helps to build real-time use cases during the end to end testing.
- Improves test gaps and helps in better test coverage.
- Tests are reliable and it is easy to isolate failures.
- Integration tests detects issues such as database connection issue, connecting queues down etc.
Advantages:
- Attain confidence that integrated modules work properly.
- The tester can start testing once the modules to be tested are available.
- Detects errors related to the interface between modules by helping modules interact with API’s and other third-party tools.
Process :
- Prepare Integration Test Plan.
- Prepare integration test scenarios and test cases.
- Create test automation scripts.
- Execute test cases.
- Report the defects.
- Track and retest the defects once fixed by developers.
Strategies for integration:
- Top Down integration testing
- Bottom Up integration testing
- Big Bang integration testing
Big Bang Testing
- Big Bang testing is a type of testing where all the components are integrated together at once and then tested as a whole.
- Individual modules are not integrated until and unless all the modules are ready.
- All the modules are integrated without performing any integration testing and then it’s executed to know whether all the integrated modules are working fine or not.
Top Down Testing
- First Test the top layer or the controlling subsystem or Start with the ‘‘root’’ and one or more called modules.
- Then combine all the subsystems that are called by the tested subsystems and test the resulting collection of subsystems
- Do this until all subsystems are incorporated into the test
- Stubs are needed to do the testing.
Bottom Up Testing
- The subsystems in the lowest layer of the call hierarchy are tested individually.
- Then the next subsystems are tested that call the previously tested subsystems
- This is repeated until all subsystems are included
- Drivers are needed.
Sandwich/Hybrid Testing
This is an approach which is a combination of Top Down and Bottom Up approaches.