Slides for my talk at #DestinationAutomation in July 2020. Code examples are here: https://github.com/berndruecker/ticket-booking-camunda-cloud

1. Automating Processes
in Modern
Hipster Architectures
@berndruecker

2. Example
@berndruecker

3. Example
Payment
Seat
ReservationBooking
Ticket
Generation

4. Example
@berndruecker
sync

5. REST?
Payment
Seat
ReservationBooking
Ticket
Generation
REST
REST
REST
REST

6. Weaknesses: Latency creep
Payment
Seat
ReservationBooking
Ticket
Generation
REST
300 ms
1150 + x ms
600 ms
250 ms

7. Weaknesses: Availabiliy erosion
Payment
Seat
ReservationBooking
Ticket
Generation
REST
99 % uptime
99 % uptime
99 % uptime
96 % uptime

8. And what about consistency?
Payment
Seat
ReservationBooking
Ticket
Generation

9. What‘s hipster?
Event-Driven
Reactive
Distributed Systems
Microservices
Agile
Streaming
Cloud-Native
Eventual Consistency
Kubernetes
Serverless

10. Event Bus
Event-Driven Choreography
Payment
Seat
Reservation
Ticket
Generation
Ticket
booked
Seat
reserved
Payment
received
Ticket
generated

11. Event Bus
Event-Driven Choreography
Payment
Seat
Reservation
Ticket
Generation
Ticket
booked
Seat
reserved
Payment
received
Ticket
generated
This is super
flexible and
de-coupled

12. Event Bus
Event-Driven Choreography
Payment
Seat
Reservation
Ticket
Generation
Ticket
booked
Seat
reserved
Payment
received
Ticket
generated
We now need
to reserve seats before
collecting payment!

13. What we wanted
Photo by Lijian Zhang, available under Creative Commons SA 2.0 License and P..19 / CC BY-SA 4.0
@berndruecker

14. The danger is that it's very easy to make
nicely decoupled systems with event
notification, without realizing that you're
losing sight of that larger-scale flow, and
thus set yourself up for trouble in future
years.
https://martinfowler.com/articles/201701-event-driven.html
@berndruecker

15. The danger is that it's very easy to make
nicely decoupled systems with event
notification, without realizing that you're
losing sight of that larger-scale flow, and
thus set yourself up for trouble in future
years.
https://martinfowler.com/articles/201701-event-driven.html
@berndruecker

16. The danger is that it's very easy to make
nicely decoupled systems with event
notification, without realizing that you're
losing sight of that larger-scale flow, and
thus set yourself up for trouble in future
years.
https://martinfowler.com/articles/201701-event-driven.html
@berndruecker

17. How-to monitor
event-driven processes?
https://camunda.com/learn/webinars/
microservices-landscape-workflow-automation/

18. Orchestration
Payment
Seat
ReservationBooking
Ticket
Generation
This component orchestrates
the others
coordinates

19. Orchestration ≠ Synchronous Communication
Payment
Seat
ReservationBooking
Ticket
Generation
Kafka
AMQP
FaaS
REST

20. A workflow engine can help
Payment
Seat
ReservationBooking
Ticket
Generation
REST

21. A workflow engine can help
Payment
Seat
ReservationBooking
Ticket
Generation
REST
A workflow engine
Keeps persistent state
Can wait
Can retry
Can escalate
Can compensate
…

22. Warning:
Contains Opinion

23. Berlin, Germany
mail@berndruecker.io
@berndruecker
Bernd Ruecker
Co-founder and
Chief Technologist of
Camunda

24. Demo

25. Architecture
Payment
Seat
Reservation
Ticket
Generation
REST
Booking
Java Spring Boot App
Camunda Cloud
Client
Camunda Cloud
Workflow Engine
AMQP
REST
Workflow engine
subscription
FakeServices
NodeJs App
https://github.com/berndruecker/ticket-booking-camunda-cloud

26. Camunda Cloud is based on Zeebe (OSS workflow engine)
http://zeebe.io/

27. But…
@berndruecker
sync

28. Can your company
leverage your
hipster architecture?
Shutterstock
You need to
change business
processes and
customer
experience!

29. @berndruecker
happy
case
failure
case
Redesign your business process accordingly!
Or some interface
to poll for status
Sync in happy case
Async response

30. Summary
• Synchronous call chains have weknesses
• Event-driven choreography is not a magic cure
• Orchestration
• Helps to avoid chaos
• Can be handled within one service (decentral)
• Does not mean synchronous communication
• To leverage a great hipster architecture you need to adjust
business processes and customer experience

31. Thank you!
@berndruecker

32. mail@berndruecker.io
@berndruecker
https://berndruecker.io
https://medium.com/berndruecker
https://github.com/berndruecker
https://www.infoq.com/articles/events-
workflow-automation
Contact:
Slides:
Blog:
Code:
https://www.infoworld.com/article/3254777/
application-development/
3-common-pitfalls-of-microservices-
integrationand-how-to-avoid-them.html
https://thenewstack.io/5-workflow-automation-
use-cases-you-might-not-have-considered/