in Microservices using DDD, Event Sourcing & CQRS Augusto Branquinho Mike Shigueru Matsumoto

Transcription

1 in Microservices using DDD, Event Sourcing & CQRS Augusto Branquinho Mike Shigueru Matsumoto

2 1. Real Wave Modules Marketing Sales Care Technical stack Frontend Integration Backend Payments Insights Integration Information

3 2. Kotlin Designed by Jetbrains Kotlin in production: Google, Pivotal, Uber, Atlassian, Coursera, etc Statically typed Modern Drastically reduce the boilerplate Java, Android Javascript Native

4 2. Kotlin Data Class tostring equals hashcode copy properties - get/set

5 2. Kotlin Lambda Java Kotlin

6 2. Kotlin Higher Order Functions

7 2. Kotlin Extension method Reified & Inline

8 2. Kotlin Smart cast Pattern matching String template Reified Operator overloading Unit and Nothing High order function Infix Internal Properties Extension methods/properties Lazy initialization, Delegation Object (singleton) Deprecated Default value Tacit programming: let, also, apply, run, with Tailrec

9 3. Event Sourcing & CQRS Event Sourcing (ES) 100% reliable logging (aka: version control) all operations on the system are stream event-oriented: nothing happens before the event being committed it is possible to rebuild all the views since the beginning of time you can build new views using the same principle events are immutable

10 3. Event Sourcing & CQRS CQRS "It's a pattern" (Greg Young) uses a different model to update (Command) and another to read (Query) Command (accept/reject) Change state Events Query (views) Are free of side effects

11 3. Event Sourcing & CQRS Motivation ES, CQRS Clients: Bank, Telecom Audit Log (query the past) Insights Multiple views (Multi-Tenant) E.g.: Catalog manager Reliable logs Offers are immutable High requests rate (millions) Decoupled views

12 3. Event Sourcing & CQRS Real Wave Microservices Command Api Query Api accept/reject query response Catalog Catalog Manager Search Offers Catalog Join Use Pay Processor

13 3. Event Sourcing & CQRS Low write latency Catalog Search High read latency Catalog Manager Catalog Processor

14 3. Event Sourcing & CQRS Code

15 3. Event Sourcing & CQRS

16 3. Event Sourcing & CQRS DDD Command Bus

17 3. Event Sourcing & CQRS Command Bus Bounded Context

18 3. Event Sourcing & CQRS Command Bus First Command Nothing was replayed yet

19 3. Event Sourcing & CQRS DDD

20 3. Event Sourcing & CQRS

21 3. Event Sourcing & CQRS Happens in the past Just accept, no logic here

22 3. Event Sourcing & CQRS Command Bus Not here yet!!!

23 3. Event Sourcing & CQRS Command Bus Replay for all past events will start for this ID before this Command executes

24 3. Event Sourcing & CQRS 1 - Replay

25 3. Event Sourcing & CQRS 1 - Replay 2 - Accepts/Rejects

26 3. Event Sourcing & CQRS 1 - Replay 2 - Accepts/Rejects 3 - Accepted

27 3. Event Sourcing & CQRS Another team maybe? Catalog Processor

28 3. Event Sourcing & CQRS

29 3. Event Sourcing & CQRS

30 3. Event Sourcing & CQRS

31 3. Event Sourcing & CQRS Catalog Search

32 3. Event Sourcing & CQRS A B F Catalog Search C D E Catalog 1 Micro Services Catalog 2 Catalog 3 Catalog n

33 3. Event Sourcing & CQRS Conclusion

34 3. Event Sourcing & CQRS Conclusion Burn down

35 3. Event Sourcing & CQRS TODO snapshots sagas Replay recovery fix inconsistency Conclusion build a new view

36 4. Kotlin, DDD, ES & CQRS Motivation Kotlin Events (immutable) (Axon) Catalog v1 Data class (boilerplate) Event Stream lambda Modern Easy to learn

37 4. Kotlin, DDD, ES & CQRS Why should you try using Kotlin?

38 4. Kotlin, DDD, ES & CQRS Sealed Class Events (Event Store Database) Pattern Matching Smart Casts Final

39 4. Kotlin, DDD, ES & CQRS Events (Event Store Database)

40 4. Kotlin, DDD, ES & CQRS Events (Event Store Database)

41 4. Kotlin, DDD, ES & CQRS Value Objects - data class Typesafe Primitive Obsession Invalid Objects Immutability

42 4. Kotlin, DDD, ES & CQRS Anemic Domain Model - kotlin extensions Only Getters / Setters Services Layers are OVER ABUSED!!!

43 5. Kotlin 102 Tests

44 5. Kotlin 102 Coroutines asynchronous programming we put the complications into libraries experimental!= unsecurity

45 5. Kotlin 102 Coroutines What's the result?

46 5. Kotlin 102 Coroutines What's the result?

47 5. Kotlin 102 Coroutines are light weight!

48 5. Kotlin 102 Coroutines are light weight!

49 5. Kotlin 102 Coroutines - async/await

50 5. Kotlin 102 Kotlin is the path to Functional Programming. Functional Programming leads to Pure Functions, Pure Functions leads to Monad and Asynchronous Programming. Asynchronous Programming leads to Reactive Programming. Master Yoda - Return of the Jedi

51 5. Kotlin 102 Functional Programming Purity (no-side effect) Referential Transparency Purity vs I/O Exceptions propagation Thread limits

52 5. Kotlin 102 Monad/Either - zkotlin

53 5. Kotlin 102 Monad - Either -> Either -> Either FOLD HELL

54 5. Kotlin 102 Either foldcompose

55 5. Kotlin 102 Either foldcompose ping-pong effect E.g. Payments Retry

56 5. Kotlin 102 Either foldcompose ping-pong effect

57 5. Kotlin 102 Either foldcompose ping-pong effect

58 5. Kotlin 102 Either, Coroutines, Extensions, zkotlin all together

59 5. Kotlin 102 Wraps I/O problems with Either<L,R>

60 5. Kotlin 102 Wraps I/O problems with Either<L,R> Remote I/O

61 5. Kotlin 102 sync {} async {}

62 5. Kotlin 102 runblocking

63 5. Kotlin 102 zkotlin Couroutines/Ext. Methods

64 5. Kotlin 102 Conclusion Kotlin & Functional Programming Purity, Referential Transparency, Immutability Higher-order functions Sugar syntax (it, ƛ as last parameter) Less boilerplate a nicer syntax to compose Either pattern Coroutines is easy to use Ready for Spring Reactor Catalog Reindex Process before Coroutines: +/- 30 m, after < 4 m

65 6. Kotlin, Java & Legacy Everything is final on Kotlin Spock Mockito

66 6. Kotlin, Java & Legacy SpringBoot - allopen final

67 6. Kotlin, Java & Legacy JPA

68 6. Kotlin, Java & Legacy Spring Data QueryDSL - Plugins (modules) Default Interface Java 8 (Kotlin ) Lambdas return - Unit

69 Conclusion Mike Shigueru Matsumoto Augusto Branquinho

70 Zup We re a fast growing company (2011), but just starting. Kevin Efrusy Accel Ventures Romero Rodrigues Buscapé Company Martin Scobari General Atlantic Silvio Genesini Silvigen Consultoria 540+ Zuppers. BH MG UI / UX / R&D / DEV São José do Rio Preto SP DEV Uberlândia MG UI / UX / R&D / DEV / SUPPORT Joinville SC R&D Ribeirão Preto SP UI/UX/DESIGN Lisboa, Portugal SALES / CONSULTING / R&D São Paulo SP SALES / CONSULTING / PMO / REQUIREMENTS UI/UX