The slides of the talk I gave at PHPDay Italy 2016. Last year the hype was on SOA, today is on the Microservices Architecture, what about tomorrow? No one knows. Whatever it is the architecture you want to use, we probably agree that the strategic goal of a tech team is to support a company business, creating customer value. How can we model our software and create an architecture to achieve that? What we are trying to do at Lendinvest, is using Domain Driven Design to drive the design of our architecture.

1. Context Oriented Architecture
Put the boundary in the right place
May 13th-14th 2016 — Verona, Italy
Leonardo Proietti
@_leopro_

2. github.com/leopro

3. “Any intelligent fool can make things
bigger, more complex and more violent.
It takes a touch of genius - and a lot of
courage - to move in the opposite
direction.”
Ernst Friedrich Schumacher

4. DDD is a learning path

5. DDD is a
learning path!

6. Take care of your Ubiquitous Language

7. You need domain experts ...

8. … and right devs, UX, designers.

10. Prototype
Getfeedback
Keep going

11. Continuous negotiation

12. Just because you can
doesn't mean you should.

13. Context Matters

14. Model

15. User Context
Customer
Context
Investor
Context
Borrower
Context

16. User
User Context Customer Context
- Register
- Login
- Verification
- Store card
- Charge card
- Apply as customer

17. User
User Context Customer Context
- Register
- Login
- Verification
- Store card
- Charge card
- Apply as customer
Identity

18. Behaviours, not only data

19. Our architecture

21. API
Client
Domain Model
Controller
Command Bus
Persistence
HTTPClient
QueueClient
Domain Model
Controller
Command Bus
Persistence
HTTPClient
QueueClient

22. User
Context
Customer
Context
API CALL

23. User
Context
Customer
Context

24. User
Context
QUEUE
Worker
(Node.js)
Customer
Context

29. Behavioural entities AKA rich modeling

32. Unit Testing

41. Mitigate the locking

42. Quick Invest
Command
Handler
Model
Worker
(Node)
API
Persistence
API
Client
Invest Command
Handler
Model
Queue

44. Third party service integration

45. Command
Handler
Model
API
Client
Worker third partyQueue
Domain
Events

46. Command
Handler
Model
API
Client
Worker third partyQueue
Domain
Events
Worker third partyQueue
Worker third partyQueue

47. Functional Testing

49. Customer
Context
Investor
Context
Request
Response

51. Customer
Context
Investor
Context
Request
Response
HTTP Client
Stub

52. Pitfalls

53. Value Object (Doctrine embeddable)

54. Value Object (Doctrine embeddable)
All the fields related to the Address in the user
table must be nullable and you have to validate
them in the model

55. Referential integrity

56. Referential integrity
Because each service has his on db, you
should find another way to enforce the
referential integrity

57. Transactional consistency

58. Transactional consistency
We are violating the transactional consistency
because we’re using the UOW to persist both
Investor and Loan

59. “At the end of the day we are
selling shoes.”
@cirpo

60. Credits

61. Thank you.

62. Questions?

63. https://joind.
in/talk/47383