Healthesystems Journey to Microservices

1. Journey to MicroservicesEvolving to a Distributed service based platform to accelerate software delivery

2. 2
About us
Sam Alexander
twitter: @samalexander10
salexander@healthesystems.com
Mark Sinclair
twitter: @marksinclair
msinclair@healthesystems.com

3. 3
Healthesystems
journey to
microservices
Evolving to a Distributed service based platform to accelerate softwaredelivery

4. 4
About microservices

5. 5
Microservices
https://martinfowler.com/articles/microservices.html

6. 6
Key drivers to microservices

7. 7
Modernize our legacy platform

8. 8
Remove Single point of failure

9. 9
Deliver Software Faster

10. 10
Mental models
Business Complexity
Maintainability
Performance

11. 11
Evolving to microservices

12. DEFINITION MARKETING
Organizations which design systems ... are
constrained to produce designs which are
copies of the communication structures of
these organizations.
- Melvin Conway, 1968
12
Conway's Law

13. 13

14. How small is a microservice?
14

15. Identify Core domains
15
Core Domain
Supporting Domain
Generic Domain
Buy/Outsourced
Parity

16. 16
Tactical approach to an individual microservice

17. 17
Monolith

18. 18
Decoupling the Monolithic

19. Refactor the ball of mud
application
PRESENTATIONLAYER
BUSINESS LAYER
DATA LAYER
19

20. Strangler Pattern
20
All Old
users
Starting
position
users
Early days
users
Half way
users
Nearly
finished
users
All NEW
finished
• Make something new that obsoletes a small percentage of something old.
• Put them live together.
• Rinse and repeat.

21. Anti-corruption layer
Prevent legacy system from polluting your pristine new code.
21
Old system
Request router
New Service
Anti-corruption
Layer
Request

22. 22
1 Multiple databases
Complexity of deploying and operating a distributed system2
Eventual consistency3
Drawbacks of a microservices architecture

23. Data Quality
23
Data has no meaning without context
- Create new table
New requirement
- Add new column
- Transform data

24. Gateway
USERS
API Gateway
External Systems
Session
Management
routing security
24

25. Data Consistency
Published eventEvent Store (pub/sub)
Eventually Consistent
25

26. Servicecomponent
Module1
Modulen
API Gateway
client request client request client request
session
management
Event Store (pub/sub)
OLAP Reporting
Business Intelligence
Data Warehouse
Enterprise
Security
Servicecomponent
Module1
Modulen
Servicecomponent
Module1
Modulen
Servicecomponent
Module1
Modulen
Servicecomponent
Module1
Modulen
26

27. 27
demo

28. 28
Event Store
Edge Gateway
users
UI
Command
Service
HTTPGET HTTPPOST/PUT
PUBLISHEVENTS
CRUD
Event
Processor
SUBSCRIBETO EVENTS
CREATE/READ
Microservice
A Single Microservice

29. 29
Tools

30. Questions?
30
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