Talk from ESUG19, Cologne, Germany

1. Software
Architecture
Stories
Guille Polito
@guillep
CNRS - UMR9189
CRIStAL

2. Enterprise
Architectures
UI Services
Business Logic DTO
DAO…

3. What I feel about
Enterprise Architectures
UI Services
Business Logic DTO
DAO…

4. The Lego System
The Stud-and-Tube coupling
Lego AS, 1958
6 bricks => 915,103,765 combina6ons

5. Not so Lego System…
UI Services
Business Logic DTO
DAO…

6. Patterns as
small-scale
architectures

7. Patterns as tools

8. Patterns as recipes

9. Architecture crafting
• understand the architecture
• modify the architecture
• make your own architecture
Pattern cooking

10. Three stories
of
Pattern cookingIceWorkingCopy
IceCommit
IceBranch
LGitCommit
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[ …a task… ] schedule
runner schedule: […a task…]
sync async …
Presenter Adapter Widget

11. Chapter I: Iceberg
Let’s talk about layers
IceWorkingCopy
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IceBranch
LGitCommit
MCVersion

12. Chapter I: Iceberg
IceWorkingCopy
IceCommit
IceBranch
LGitCommit
MCVersion

13. High level: user Low level: backend
IceWorkingCopy
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IceBranch
LGitCommit
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Chapter I: Iceberg

14. High level: user Low level: backend
IceWorkingCopy
IceCommit
IceBranch
LGitCommit
MCVersion
Chapter I: Iceberg

15. Chapter I: Iceberg
High level: user Low level: backend
IceWorkingCopy
IceCommit
IceBranch
LGitCommit
MCVersion
Layers separate
levels of
abstraction

16. High level: user Low level: backend
IceWorkingCopy
IceCommit
IceBranch
LGitCommit
MCVersion
Chapter I: Iceberg

17. Chapter I: Iceberg
High level: user Low level: backend
IceWorkingCopy
IceCommit
IceBranch
LGitCommit
MCVersion

18. Chapter I: Iceberg
High level: user Low level: backend
IceWorkingCopy
IceCommit
IceBranch
LGitCommit
MCVersion
Isolate
message-crossing
points

19. But several layers,
there will be…
Presenter Adapter Widget
Chapter II: Spec

20. Chapter II: Spec
Presenter Adapter Widget

21. Chapter II: Spec
Presenter Adapter Widget
user-level backend

22. Morphic
Chapter II: Spec
Presenter Adapter Widget
user-level backend
user-level
client!

23. Morphic
Chapter II: Spec
Presenter Adapter Widget
user-level backend
user-level
client!

24. client!
user-level backend
user-level
Morphic
Chapter II: Spec
Presenter Adapter Widget
Loose coupling
via
event-messages

25. Morphic
Chapter II: Spec
Presenter Adapter Widget
user-level backend
user-level
client!

26. Morphic
Chapter II: Spec
transient
stateful
user-level backend
user-level
Presenter Adapter Widget
client!

27. Morphic
Chapter II: Spec
Presenter Adapter Widget
transient
stateful
user-level backend
user-leveluser!
Layers separate
state
management

28. Separate components
only they shall not…
Chapter III: TaskIt
[ …a task… ] schedule
runner schedule: […a task…]
sync async …

29. Chapter III: TaskIt
[ …a task… ] schedule
and eventually execute

30. [ …a task… ] schedule
and eventually execute
but how?
Chapter III: TaskIt

31. [ …a task… ] schedule
runner schedule: […a task…]
sync async …
Convenience
Explicit
Chapter III: TaskIt

32. [ …a task… ] schedule
runner schedule: […a task…]
sync async …
Convenience
Control
Chapter III: TaskIt
**Thin** convenience layers
on top of explicit layers

33. Three lessons of
Architecture crafting
separate by levels of abstraction
isolate points of failure
separate stateful from stateless
be explicit, as less magic as possible
Guille Polito
@guillep
CNRS - UMR9189
CRIStAL