Test more and better with less friction

Testing in modern software development is, and has always been, a
challenge for the industry. Everyone claims to want to do more of it but often finds themselves falling short. Some find testing to be the most tedious part of their job.

Testing has become more complicated in recent years due to the popularity of microservices and other distributed architectures. However, the way we tested it mostly stayed the same.

This talk will explore practical techniques, tools, and more to make testing easier and more approachable, to test more with less. Some of the things we will look at are TestContainers, contract testing and testable code and architectures.

Transcript

1. Test more and better with less friction
2. This talk • Introduction and theory • Managing external dependencies • Testcontainers • API-mocking • Contract testing • Why your unit tests are a mess (and how to fix it)
3. About me • Consultant @ bspoke • Tech Lead • Architect • Senior Developer • Subject Manager • Focus on developer processes
4. About me • Consultant @ bspoke • Tech Lead • Architect • Senior Developer • Subject Manager • Focus on developer processes Lazy
5. Short-term lazy vs Long-term lazy
6. • Costs more to discover issues in production. • Faster deliveries. • Enables automation. • Creates a safer environment for developers.
7. Developers should not test manually.
8. Developers should not test manually. And if you have to, your test strategy isn’t good enough.
9. System
10. System Test our code
11. System Test our code Test integrations
12. System Test our code Verify we don’t break callers Test integrations
13. System Test our code Verify we don’t break callers Test the system as a whole Test integrations
15. No manual setup required – just works Test runs execute the same on local machine and pipeline Easy to match version for dependency with version in production
16. No manual setup required – just works Test runs execute the same on local machine and pipeline Easy to match version for dependency with version in production Demo time!
17. API mocking
18. API mocking System Mocked service Demo time!
19. API mocking System Mocked service Real service =
20. Contract testing
21. The problem with broad integration/E2E tests Execute Mocked system
22. The problem with broad integration/E2E tests Execute Mocked system
23. The problem with broad integration/E2E tests Execute Mocked system
24. The problem with broad integration/E2E tests Execute Mocked system
25. The problem with broad integration/E2E tests Execute Mocked system
26. External environments System Other system Some environment Dev machine
27. System Other system Some environment Dev machine System Pipeline Integration test External environments
28. System Other system Some environment Dev machine System Pipeline Integration test System Other devs machines External environments
29. System Other system Some environment Dev machine System Pipeline Integration test System Other devs machines Devs making changes Ops making changes External environments
30. System A System B Request Response
31. System A System B Request Response Contract Expected request Expected response Response from contract Request from contract
32. System A System B Request Response Contract Expected request Expected response Response from contract Request from contract Cloud contract Demo time!
33. Contract testing vs schema
34. Unit testing What is a ”unit” anyway?
35. Unit testing Sociable unit tests Solitary unit tests Focused on testing behavior Focused on testing interactions
36. Service API Integration Business logic Input DB/Kafka/External calls/etc
39. Mock Mock Mock Solitary unit testing
40. Sociable unit testing
41. Sociable unit testing Interface Interface Interface
42. Sociable unit testing Interface Interface Interface
43. Sociable unit testing Interface Interface Interface Interface Interface Interface Interface Interface Interface
44. Sociable unit testing Interface Interface Interface Interface Interface Interface Interface Interface Interface Repository Repository Repository Repository
45. Interface Sociable unit testing Interface Interface Interface Repository Interface Interface Interface Repository Repository Interface Repository Repository Interface Interface
46. Interface Sociable unit testing Interface Interface Interface Repository Interface Interface Interface Repository Repository Interface Repository Repository Interface Interface Sociable unit tests Solitary unit tests 1 class instance 3 mocks 6 class instances 5 mocks/tables
47. TransactionService Responsible for everything related to transactions Create transaction
48. TransactionService Responsible for everything related to transactions Create transaction TransactionRepository
49. TransactionService Responsible for everything related to transactions Create transaction TransactionRepository AccountService Update account AccountRepository
50. TransactionService Responsible for everything related to transactions Create transaction TransactionRepository AccountService Update account AccountRepository BonusService BonusRepository
51. TransactionService Responsible for everything related to transactions Create transaction TransactionRepository AccountService Update account AccountRepository BonusService BonusRepository Bonus payout Create transaction
52. TransactionService Responsible for everything related to transactions Create transaction TransactionRepository AccountService Update account AccountRepository BonusService BonusRepository Bonus payout BonusPayoutService
53. CreateTransactionUseCase BonusPayoutUseCase Create transaction Bonus payout Application layer
54. CreateTransactionUseCase BonusPayoutUseCase Create transaction Bonus payout Application layer TransactionRepository AccountRepository BonusRepository Database layer
55. CreateTransactionUseCase BonusPayoutUseCase TransactionRootAggregate Account BonusRootAggregate Domain layer Create transaction Bonus payout Application layer TransactionRepository AccountRepository BonusRepository Database layer
56. Service API Integration Application logic Business logic Input DB/Kafka/External calls/etc
57. Service API Integration Application logic Input DB/Kafka/External calls/etc Domain Business logic • No database calls • No web calls • No dependencies
58. Service API Integration Application logic Input DB/Kafka/External calls/etc Domain Business logic • No database calls • No web calls • No dependencies Unit test this High-level test to verify that system is put together correctly
60. Acknowledgement • Practical test pyramid (Ham Vocke): https://martinfowler.com/articles/practical-test-pyramid.html • TDD, where did it all go wrong? (Ian Cooper): https://www.youtube.com/watch?v=EZ05e7EMOLM • BUILD STUFF'13: Ian Cooper - TDD, where did it all go wrong: https://www.youtube.com/watch?v=HNjlJpuA5kQ • Unit Test (Martin Fowler): https://martinfowler.com/bliki/UnitTest.html
61. The end Website: lindbakk.com Email: contact@lindbakk.com bspoke: bspoke.no/kontakt-oss Code: https://github.com/atomfinger/JavaZone-2024