MTC2018 - Mercari API: from Monolithic to Microservices

Speaker: Tonghui Li

Mercari has evolved tremendously in the last 5 years, and so is our code base. As of 2018, the backend API is a monolithic repository of half-million lines of code, serving all the functions of the Mercari web and mobile applications. It is becoming a bottle neck of our growth, in terms of both the system and the organization. This talk will focus on how we migrate the monolithic backend API to a microservice architecture, the methodology we choose and the lessons we learned.

Transcript

1. Mercari API: from Monolithic to Microservices Tonghui Li Tech Lead (Backend)
2. Tech Lead Backend Tonghui Li
3. Mercari API: from Monolithic to Microservices
4. Background
5. Mercari API
6. Mercari API iOS Android web
7. Mercari API iOS Android web
8. Mercari API iOS Android web admin tools
9. Mercari API iOS Android web admin tools
10. • 500 KLOC • 100+ contributors • 100 PR / week Mercari API iOS Android web admin tools
11. • 500 KLOC • 100+ contributors • 100 PR / week • And growing! Mercari API iOS Android web admin tools
12. How to migrate to microservices
13. How to migrate to microservices • Implement new features in microservices • Break down existing API into multiple services
14. How to implement new features
15. client Mercari API
16. client Service X Service Y Mercari API
17. client Service X Service Y Mercari API
18. API Gateway Service X Service Y Mercari API client
19. API Gateway Service X Service Y Mercari API client SSL termination DDos protection Authn and Authz Traffic routing Logging and tracing
20. Technical Stack
21. API Gateway Service X Service Y Mercari API client Sakura
22. API Gateway Service X Service Y Mercari API client Sakura GCP
23. API Gateway Service X Service Y Mercari API client Sakura kubernetes GCP
24. API Gateway Service X Service Y Mercari API client Sakura kubernetes GCP
25. API Gateway Service X Service Y Mercari API client Sakura kubernetes GCP
26. API Gateway Service X Service Y Mercari API client Sakura kubernetes GCP
27. How to break down existing API
28. API Gateway Service X Service Y Mercari API client
29. API Gateway Service X Service Y Mercari API client
30. Start from UX features
31. Mercari Login Buy Sell Search Shipping ...
32. Analyze fundamental components
33. Mercari Login Buy Sell Search Shipping ... User Item Photo User Item Address
34. Split them into microservices
35. Gateway Login Buy Sell Search Shipping ... User Item Photo Notification Address ...
36. Gateway Login Buy Sell Search Shipping ... User Item Photo Notification Address ...
37. Gateway Login Buy Sell Search Shipping ... User Item Photo Notification Address ... BFF Layer DAO Layer notf db user db item db s3
38. In reality...
40. How to migrate to microservices • Implement new features in microservices ◦ API Gateway ◦ Technical stack: Kubernetes, Go, gRPC, etc. • Break down existing API into multiple services ◦ Start from UX features ◦ Analyze fundamental components ◦ Split them into microservices
41. Challenges
42. Challenges: Testing With so many services, how do we test them?
43. Challenges: Testing With so many services, how do we test them? • Enforce unit tests coverage • Automated integration tests • Reduce manual QA process
44. Challenges: DB DB is in Sakura but microservices are in GCP.
45. Challenges: DB DB is in Sakura but microservices are in GCP. • Run DAO layer services in Sakura • Migrate DB from Sakura to GCP • Create Tokyo DC and host DB / services in it
46. Challenges: Transactions and Locking
47. Challenges: Transactions and Locking 　　　 Distributed Locking
48. Challenges: Transactions and Locking 　　　 Refactor with PubSub
49. Challenges: Transactions and Locking Eventual Consistency!
50. Thank you!