This document discusses using decision modeling notation (DMN) for implementing business rules. It provides examples of how decision tables can be used to model requirements and implement rules in a readable and executable way. It also discusses how DMN supports decision logic, expressions, requirements diagrams, and scoring to model a variety of business decisions around areas like risk assessment, fee calculation, and claim routing. The document recommends DMN as a way to implement rules that balances business readability and technical executability.

1. Geschäftsregeln mit DMN
Bernd Rücker | http://bernd-ruecker.com/ | @berndruecker

2. Assume you
want a new
fixed line
being
activated

3. Functional requirements

4. Implementation

5. Your rule implementation?

6. Another
example…

7. Decision table

8. Decision table
Stored as XML,
directly executable

9. http://camunda.org/
Open Source (ASL)

10. Demo

11. Recap

12. Recap

13. FEEL
(Friendly Enough Expression Language)

14. FEEL

15. FEEL

16. FEEL

17. More complex epressions possible

18. More complex expressions possible

19. Register own functions

20. Typical non-functionial requirements
Requirement What business analysts may say
Visibility How is the rule implemented today? ✓
Changeability Please change that rule quickly!
Let me quickly change that rule myself.
✓
Traceability Why was this decision taken in this
concrete situation?
Inside How frequent are certain decisions?

21. Lightweight and composable platform
DB
Java
Engine
Platform
(Repository, History, REST-API, …)
Cockpit
Modeler
dmn.io
http://camunda.org/
OSS - Apache License

22. Demo

23. Recap

24. Recap

25. Too simple?

26. Decision Requirement Diagrams
Entscheidung
Input
Wissensquelle
(Knowlege source)
Geschäftswissens-
modell
(Business knowledge)

27. Demo

28. Recap

29. Sturm Niklas, Münsterland Zeitung, 01.04.2015
Kumulschaden, der
Der Kumulschaden ist die
Summe von mehreren einzelnen,
bei unterschiedlichen
Versicherungsnehmern
eingetretenen Schäden, die
regional durch das gleiche
Schadensereignis verursacht
wurden.

30. That means
Münster
München

31. Workshop
Business
IT
Decision
Analyst
The „DRD“

32. The result
Required Skills
Employee
Suitability Score
Claim: Affected
Object
Claim: Type
Claim:
Expenditure
Employee:
Claims assigned
Employee Claim
Approval
Authority
Employee
Experience
Determine
Employee

33. The result
Required Skills
Employee
Suitability Score
Claim: Affected
Object
Claim: Type
Claim:
Expenditure
Employee:
Claims assigned
Employee Claim
Approval
Authority
Employee
Experience
Determine
Employee
Expression:
Use employee
with best score

34. Problem: Multiplicity. Not (yet) adressed by DRD!
Required Skills
Employee
Suitability Score
Claim: Affected
Object
Claim: Type
Claim:
Expenditure
Employee:
Claims assigned
Employee Claim
Approval
Authority
Employee
Experience
Determine
Employee
per claim
(1 time)
per claim
and employee
(n times)
Result:
1 employee

35. Demo

36. Recap

37. Decision Flow

38. Implementation as Decision Flow

39. Decision Flow
for (var i=0; i<employees.length; i++) {
if (!selectedEmployee ||
employees[i].score > selectedEmployee.score){
selectedEmployee = employees[i];
}
}
Simple Expressions can be
best expressed as Script Tasks,
e.g. using JavaScript

40. Seperate Decision Flow from Business Process

41. Bernd Rücker
Consultant & Evangelist
> 10+ years workflow & rules
http://bernd-ruecker.com/
bernd.ruecker@camunda.com
Co-founder Camunda
http://camunda.org/

42. Developer
friendly

43. More benefits for the developer
• Implement rules much faster
• Extract rules from cluttering your code base
• Keep remaining code more stable
• Ownership on rules

44. DMN Summary & Scope
Decision Table
Decision Logic
FEEL (Friendly enough expression language)
Literal Expressions
Decision
Requirements
Diagram
(DRD)
Scoring
Automatsisierte Risiko-
bewertung von Anträgen
Gebührenberechnung
Automatische Berechnung
von Gebühren
Skill-based routing
Automatisierte Zuweisung
von Anträgen zu Mitarbeitern
Validierung
Automatische Validierung
von Rückversicherungen

45. http://camunda.org
https://github.com/berndruecker/
camunda-dmn-intro

46. Takeaways & Empfehlung
• DMN gelingt die
Kombination von
„fachbereichslesbar“ und
„ausführbar“ sehr gut
• Entscheidungstabellen
sind einfach zu verstehen
und vielseitig einsetzbar
• DMN verbreitet sich
rasant

47. Vielen Dank! Fragen?