1. CQRS & Event Sourcing Distributed Architecture Patterns
Dylan Smith
Senior ALM Consultant
Microsoft MVP (ALM)

2. Who Am I? Dylan Smith @dylan_smith
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Solution Architect
ALM Consultant
Developer Mentor

3. World Leader in Microsoft Systems Integration
with Fortune 200 Companies
Over 1800 Microsoft ALM Engagements
Over 650 Microsoft ALM Customers
Over 500 Microsoft Development Customers
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4. Agenda Typical Distributed Architectures What is CQRS?
What is Event Sourcing?
CODE !!!
Benefits / Challenges

5. Transaction Script Data Storage Application Services Remote Facade
Send DTO
Status Returned
Request DTO
DTO Returned
Client

6. Active Record Data Storage Entity Entity Application Services
Remote Facade
Send DTO
Status Returned
Request DTO
DTO Returned
Client

7. Domain Model Data Storage Repository Application Services
Domain Object
Domain Object
Application Services
Remote Facade
Send DTO
Status Returned
Request DTO
DTO Returned
Client

8. CQRS Data Storage Data Storage Repository Command Handlers
Domain Object
Domain Object
Command Handlers
Query Handlers
Remote Facade
Remote Facade
Send Command
Ack/Nak Response
Request DTO
DTO Returned
Client

9. Sample Read Data Model

10. Event Sourcing
Line Items (n)
Purchase Order
Shipping Information

11. Event Sourcing Order Created Added 2 Shirts Added 4 Hats
Shipping Info Added

12. CQRS + Event Sourcing Event Bus Event Store Data Storage
Event Handlers
CQRS + Event Sourcing
Repository
Domain Object
Domain Object
Command Handlers
Query Handlers
Remote Facade
Remote Facade
Send Command
Ack/Nak Response
Request DTO
DTO Returned
Client

13. Event Store Data Schema

15. Command

16. Event

17. Command Handler

18. Domain Object

19. Event Handler

20. Query Handler

21. Data Transfer Object (DTO)

25. Scalability

27. Sample Unit Test

28. Sample Unit Test #2

29. Domain
Read Model
Events
DTOs
Commands
Client

30. Recommended Reading

31. Code Samples Super Simple CQRS Example Microsoft P&P – CQRS Journey
github.com/gregoryyoung/m-r
Microsoft P&P – CQRS Journey
Google “CQRS Journey”
NCQRS
ncqrs.org
The CQRS Kitchen
thecqrskitchen.codeplex.com
Lokad-CQRS
code.google.com/p/lokad-cqrs

32. Ask any question
Q&A

33. Dylan Smith, Microsoft ALM MVP
ideas. technology. imagine.
Thanks for your time!
Dylan Smith, Microsoft ALM MVP