Domain-Driven Transformation

Transcript

1. Starring Directed By Special Appearance Presented by Photo: Hackercatxxy/Wikipedia
3. @hschwentner
4. @hschwentner
5. @hschwentner
6. @hschwentner
7. @hschwentner
9. @hschwentner
12. THE NAME OF THIS SPEAKER IS HENNING SCHWENTNER LIVE 45 MIN TALK
13. !"# Kolleg:in gesucht (Deutschlandweit)
15. Story Time
16. @hschwentner Alphorn Auto Leasing Inc.
17. @hschwentner
18. @hschwentner
19. Monolease A
20. salesperson [person] Monolease [software system] Central car leasing tool customer [external person] risk manager [person] closes leasing contracts with creates and calculates contracts in assesses risk of contracts in Alphorn Auto Leasing Inc. [enterprise] Context
21. @hschwentner Photo: Myriam Thyes/Wikipedia
22. @hschwentner Photo: Keiichi Inoue/flickr
23. @hschwentner Alphorn’s boss: “Modernize it!”
24. @hschwentner Photo: Keiichi Inoue/flickr
25. @hschwentner Diagnosis: From Which Diseases Does Our Patient suffer?
26. @hschwentner Different diseases require different treatment
27. @hschwentner big ball of mud code with poorly expressed domain knowledge bad team organization Typical Diseases of Legacy Systems
28. @hschwentner big ball of mud code with poorly expressed domain knowledge bad team organization Cures strategic transformation tactical transformation team-organizational transformation
29. @hschwentner Domain-Driven Refactorings • Strategic Refactorings • Tac0cal Refactorings (Against Big Ball of Mud) Catalog: https://hschwentner.io/domain-driven-refactorings strategic transformation tactical transformation team-organizational transformation • Socio-Technical • Tac0cal refactorings (Against Model Anemia)
30. @hschwentner Strategic
31. @hschwentner Strategic Transformation 1. Step: Domain re-discovery 2. Step: Modeling the target architecture 3. Step: Aligning current with target architecture 4. Step: Do the move
32. @hschwentner Strategic Transformation 1. Step: Domain re-discovery 2. Step: Modeling the target architecture 3. Step: Aligning current with target architecture 4. Step: Do the move
33. @hschwentner Step 1: Domain Re-Discovery
34. @hschwentner To split the monolith we first have to put it aside
35. Mindset Switch
36. thinking about business => thinking about technology to
37. Collaborative Modeling
38. Collaborative Modeling
39. customer tells wish for 1 salesperson signs to gives for contract 3 risk manager contract passes on to 4 contract votes checks calculates 5 6 7 calculates to 8 2 car credit rating installment car resale value contract
40. https://hschwentner.io Read on in:
41. May 6th-9th 2024 Vienna, Austria The Collaborative Modeling Unconference comocamp.org Event Storming User Story Mapping Event Modeling Impact Mapping Domain Storytelling Storystorming Context Mapping Example Mapping etc.
42. @hschwentner Step 2: Determining the Target Architecture
43. Drawing Boundaries
44. @hschwentner Scope: coarse-grained to-be (optimized) pure
45. Which activities belong together (from an actor’s perspective)?
46. customer tells wish for 1 salesperson signs to gives for contract 3 risk manager contract passes on to 4 contract votes checks calculates 5 6 7 calculates to 8 2 car credit rating installment car resale value contract sales risk assessment
47. sales risk assessment
48. @hschwentner Step 3: Aligning Current Architecture with Target Architeture
49. @hschwentner Determining the Current Architecture analysis tool developers architecture analyst source code
50. https://sustainable-software- architecture.com Read on in: analysis tool architecture analyst
51. Monolease [software system] salesperson [person] Monolease [software system] Central car leasing tool customer [external person] risk manager [person] closes leasing contracts with creates and calculates contracts in assesses risk of contracts in Alphorn Auto Leasing Inc. [enterprise] Context again
52. backend [container] database [container] frontend [container] salesperson [person] backend [container: EJB 2] risk manager [person] creates and calculates contracts in assesses risk of contracts in Monolease [software system] frontend [container: servlets, JSPs] database [container: IBM DB2] Containers
53. Calculator [component] frontend [container] LeasingServlet [component: servlet] CONTRACTS [database table] PartnerServlet [component: servlet] ContractService [component] PartnerService [component] backend [container] database [container] Contract [component] Partner [component] PARTNERS [database table] Components
54. big ball of mud => no vertical structuring
55. Calculator [component] frontend [container] LeasingServlet [component: servlet] CONTRACTS [database table] PartnerServlet [component: servlet] ContractService [component] PartnerService [component] backend [container] database [container] Contract [component] Partner [component] PARTNERS [database table] Components
56. Calculator [component] ContractService [component] PartnerService [component] backend [container] Contract [component] Partner [component] Component Backend
57. Component Bounded Contexts Sales Risk assessment
58. Calculator [component] ContractService [component] PartnerService [component] Contract [component] Partner [component] Component Bounded Contexts Sales Risk Assessment
59. Calculator [component] ContractService [component] PartnerService [component] Contract [component] Partner [component] Sales Risk Assessment Contract [component] Partner [component] Duplication?
60. ContractService [component] Contract [component] Component Backend Sales Risk assessment
61. ContractService signContract() voteContract() Code Contract getContractNumber() setSignatureDate() setCreditRa7ng() setVo7ngResult() Sales Risk Assessment
62. ContractService signContract() voteContract() Code Contract getContractNumber() setSignatureDate() setCreditRa7ng() setVo7ngResult() Sales Risk Assessment ContractService signContract() voteContract() Contract getContractNumber() setSignatureDate() setCreditRa7ng() setVo7ngResult()
63. ContractService signContract() Code Contract getContractNumber() setSignatureDate() Sales Risk Assessment ContractService voteContract() Contract getContractNumber() setCreditRa7ng() setVo7ngResult()
64. ContractService signContract() Code Contract getContractNumber() setSignatureDate() Sales Risk Assessment ContractService voteContract() Contract getContractNumber() setCreditRating() setVotingResult()
65. @hschwentner 1.2 Extract Specialized “Contract Service” 1.1 Extract Specialized “Contract” 1 Extract Context “Sales” Improvement Backlog 2 Extract Context “Risk assessment” 2.1 Extract Specialized “Contract Service” 2.1 Extract Specialized “Contract”
66. @hschwentner Step 4: Do the Move
67. @hschwentner Improvement Backlog Planning Transformation Tactical Refactoring 1.1 Strategic Refactoring 1 User Story A Product Backlog User Story E User Story B User Story C User Story D Tactical Refactoring 1.2 Tactical Refactoring 1.3 Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog
68. @hschwentner Improvement Backlog Planning Transformation User Story A Product Backlog User Story E User Story B User Story C User Story D Sprint Backlog Tactical Refactoring 1.1 Strategic Refactoring 1 Tactical Refactoring 1.2 Tactical Refactoring 1.3 Tactical Refactoring 2.1 Strategic Refactoring 2
69. @hschwentner Improvement Backlog Planning Transformation Tactical Refactoring 1.1 Strategic Refactoring 1 User Story A Product Backlog User Story E User Story B User Story C User Story D Tactical Refactoring 1.2 Tactical Refactoring 1.3 Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog
70. @hschwentner Improvement Backlog Planning Transformation Strategic Refactoring 1 Product Backlog User Story E User Story C User Story D Tactical Refactoring 1.3 Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog
71. @hschwentner Improvement Backlog Planning Transformation Strategic Refactoring 1 Product Backlog User Story E User Story C User Story D Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog User Story F User Story G Tactical Refactoring 1.3
72. @hschwentner Improvement Backlog Planning Transformation Strategic Refactoring 1 Product Backlog User Story E User Story C User Story D Tactical Refactoring 1.3 Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog User Story F User Story G
73. @hschwentner Improvement Backlog Planning Transformation Product Backlog User Story E Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog User Story F User Story G
74. @hschwentner Improvement Backlog Planning Transformation Product Backlog User Story E Tactical Refactoring 2.1 Strategic Refactoring 2 Sprint Backlog User Story G User Story H User Story F User Story I
75. ContractService signContract() voteContract() Code Contract getContractNumber() setSignatureDate() setCreditRa7ng() setVo7ngResult() Risk Assessment ContractService Contract Monolease voteContract() getContractNumber() setCreditRa7ng() setVotingResult()
76. ContractService signContract() Code Contract getContractNumber() setSignatureDate() Risk Assessment ContractService Contract Monolease voteContract() getContractNumber() setCreditRa7ng() setVo7ngResult()
77. @hschwentner Tactical
78. Code Risk Assessment ContractService voteContract() Contract getContractNumber() setCreditRa7ng() setVo7ngResult() anemic
80. Code Risk Assessment ContractService voteContract() Contract getContractNumber() setCreditRa7ng() setVo7ngResult()
81. Code Risk Assessment ContractService voteContract() - rateCustomer() Contract getContractNumber() setCreditRa7ng() setVo7ngResult()
82. Code Risk Assessment ContractService voteContract() Contract getContractNumber() setCreditRa7ng() setVo7ngResult() rateCustomer()
83. @hschwentner Excercise
84. @hschwentner Mob programming: - Apply tactical refactorings to Anemic LeasingNinja Exercise
85. @hschwentner Team- Organizational
86. “Organizations which design systems are constrained to produce designs which are copies of the communication structures of these organizations.” Melvin Conway
87. Melvin Conway (1967) “Organiza9ons which design systems are constrained to produce designs which are copies of the communica9on structures of these organiza9ons.”
88. “The organiza9on of the so;ware and the organiza9on of the so;ware team will be congruent.” Eric Raymond
89. “If you have four groups working on a compiler, you'll get a 4-pass compiler.” Eric Raymond
90. @hschwentner Be careful with Layer Teams Presentation Logic Data team A team B team C
91. @hschwentner Cross-Functional Teams Presentation Logic Data team A team B team C
92. @hschwentner Outlook
93. @hschwentner What Else? Socio-technical transformation Technical transformation Tactical transformation Anti-Anemia refactorings
94. @hschwentner Domain Categories Pipeline Domain Blackboard Domain Dialog Domain • Logis&cs • Insurances and banks • administra&on • healthcare • event management • control center • Software development • Communication software • Nego&a&ons in various domains or Domain Patterns?
95. @hschwentner Conclusion
97. https://hschwentner.io Read on in: h6ps://hschwentner.io/domain-driven-refactorings
98. Lesson: is possible Monolith transformation (and hard) =>
99. @hschwentner Mistake: Going on the journey alone Better:
100. Photo: Henning Schwentner
101. ! ❤
102. @hschwentner
103. Bibliography Foote, Brian and Joseph Yoder. “Big Ball of Mud.” PLoP ’97, Monticello, IL, September 1997. Fowler, Martin. “Strangler Fig Application.” Bliki, June 29, 2004. Hofer, Stefan and Henning Schwentner. Domain Storytelling: a Collaborative, Visual, and Agile Way to Develop Domain-Driven Software. Boston: Addison- Wesley, 2022. Lilienthal, Carola. Sustainable Software Architecture: Analyze and Reduce Technical Dept. Heidelberg: dpunkt, 2019. Lilienthal, Carola and Henning Schwentner. Domain-Driven Transformation: Modularize and Modernize Legacy Software. Boston: Addison-Wesley, 2025. Kernighan, Brian W. Software Tools in Pascal. Addison-Wesley, 1981.
105. Henning Schwentner ⌂ https://hschwentner.io in/henningschwentner hs@wps.de Kolleg:in gesucht (Deutschlandweit)