Testing microservices the right way

Microservices shine in many aspects, but testability. Whenever you deploy a service, no matter how small it is, as long as it has dependencies, you have to keep them in mind. In Toptal, we realized the complexity of the integration testing when started our path from a monolithic application to microservices. In this talk, I’ll show what criteria we used to make a smart decision, what tools we haven’t chosen and how contract testing simplified our development flow and CI.

Transcript

1. Testing microservices the right way Tatiana Shepeleva @ Toptal
2. Tatiana Shepeleva @ Toptal
3. • I am Quality Assurance Engineer • Love my job • 36 countries
4. toptal.com
5. Testing microservices the right way
6. Microservices are great
7. Microservices are light
8. Microservices are isolated
9. Microservices are fun
10. Microservices are fun
12. ~2000 end-to-end* tests * also known as acceptance, UI or business tests
13. ~3800 min
17. Complications • Have different databases • Use different languages • Work with different protocols
18. +5 min/service
19. What’s wrong with end-to-end tests? • Expensive and complex infrastructure • Time consuming • Flaky
22. Test integration separately
23. Requirements •Ruby •JavaScript •Scala/JVM •Elixir •WebSocket support •Easy to update tests •Provider can’t break consumers
24. Record & Replay
27. Record & Replay Polly.JS VCR Ruby ❌ ✅ JavaScript ✅ ✅ Scala/JVM ❌ ✅ Elixir ❌ ✅ WebSocket support ✅ ❌ Easy to update tests ❌ ❌ Provider can’t break consumers ❌ ❌
28. Fake server
30. Fake servers Wiremock Mockserver Ruby ✅ ✅ JavaScript ✅ ✅ Scala/JVM ✅ ✅ Elixir ❌ WebSocket support ❌ ❌ Easy to update tests ✅ ✅ Provider can’t break consumers ❌ ❌
31. Contract tests
35. Contract tests Spring Cloud Pact Ruby ❌ ✅ JavaScript ❌ ✅ Scala/JVM ✅ ✅ Elixir ❌ Web Socket support Easy to update tests ✅ ✅ Provider can’t break consumers ✅ ✅
36. Cons • Expensive and complex infrastructure ✅ • Time consuming ✅ • Flaky ✅
37. Cons • Not a functional testing
38. docs.pact.io
39. Pact • Support different languages (Ruby, JS, Go, PHP, Python, JVM) • Framework-agnostic • Language-agnostic contract (JSON)
47. GraphQL?
52. WebSockets?
53. Experimental support Pact-JS
54. gRPC?
55. No but may be - #protobufs
56. Storage for contracts • Your CI • Your codebase • Pact Broker
57. Pact Broker • Stores versions and tags • Webhooks to trigger checks or notifications • can-i-deploy tool
62. Pact Broker PactFlow
65. How is it actually going to work?
66. Consumer flow
67. Consumer flow
68. Consumer flow
69. Consumer flow
70. Consumer flow
71. Consumer flow
72. Consumer flow
73. Consumer flow
74. Consumer flow
75. Provider flow
76. Provider flow
77. Provider flow
78. Provider flow
79. Provider flow
80. Provider flow
81. The Right Way • 10 instead of 3800 min • Contract tests are a part of unit tests • Number of end-to-end tests minimal
82. The end Tatiana Shepeleva tati.engineer