apidays Helsinki & North 2023 API Ecosystems - Connecting Physical and Digital June 5 & 6, 2023 API : First design VS Design First Understand the animate and inanimate object role ! Patrick Brosse, Head of API Design at Amadeus IT Group ------ Check out our conferences at https://www.apidays.global/ Do you want to sponsor or talk at one of our conferences? https://apidays.typeform.com/to/ILJeAaV8 Learn more on APIscene, the global media made by the community for the community: https://www.apiscene.io Explore the API ecosystem with the API Landscape: https://apilandscape.apiscene.io/

1. API : First design VS Design First
Understand the animate and inanimate object role !
Patrick Brosse
Head of API Design
Amadeus IT Group

3. Design=API_Contract
APIDesigner

4. GET / api / design ?
from = “Coding first ” &
to = “Design first” &
with = “D.D.D.”
Patrick Brosse
Head of API Design & Data Model
Amadeus IT Group

5. Build an elegant,
future-proof API in
minimum time
Challenge Safe Travel API
Elegant
Complex functionality, simple to use
Future-proof
Update without affecting original design.
Minimum time
Urgency due to pandemic.

6. Codefirst
Solution #1
GET / api / code-first
200 OK
{
from: “Software”
to: “Api contract”
via: “Swagger generator”
}

7. Designfirst
GET / api / design-first
200 OK
{
from: “Api contract”
to: “Software”
via: “code generator”
}
Solution #2

8. Before the Design first( Solution #1)
First Design
Source : https://www.eyrolles.com/Informatique/Livre/domain-driven-design-9780321125217/

9. VolatileKnowledge
1– DDD : Before Crunching
GET / knowledge / sum-up
400 Not Found
{
from: “Business”
to: “Developer”
via: “Documentation”
}

10. StableKnowledge
2– DDD : Crunching
POST / ddd / knowledge
201 Created
{
from: “Waterfall”
to: “Agile”
via: “Domain Data Model”
}

11. Domainmodel
3– DDD : Effective Modeling
POST / ddd / models
200 OK
{
from: “Business”
to: “API Contract”
via: “DDD”
}

12. REST – uri / path
6-DDD : Bounded Context
GET / ddd / layers
{
from: domain-relationship
to : links
via : path &
content-type
endpoints
}

13. REST – uri / path
6-DDD : Bounded Context
GET / ddd / layers
{
from: domain-relationship
to : links
via : path &
content-type
endpoints
}

14. REST - Resource
5-DDD – Entity/ Aggregate
GET / ddd / entities
200 OK
{
from: root-entity
to : resources
}

15. REST - Resource
5-DDD – Entity/ Aggregate
GET / ddd / entities
{
from: entity
to : resources
}

16. REST - Resource
5-DDD – Entity/ Aggregate
GET / ddd / entities
{
from: entity
to : resources
}

17. REST - Resource
5-DDD – Entity/ Aggregate
GET / ddd / entities
{
from: entity
to : resources
}

18. REST - Resource
5-DDD – Entity/ Aggregate
GET / ddd / entities
200 OK
{
from: root-entity
to : resources
}

19. REST - Component
6-DDD : Value Object
GET / ddd / reusability
{
from: Value-object
to : Component
}

20. REST - Component
6-DDD : Value Object
GET / ddd / reusability
{
from: Value-object
to : Component
}

21. FirstDesign
7– Keytakeaways
GET / ddd / api
200 OK
{
from: “Business”
to: “API Contract”
via : “Data Model”
}

22. Thank you!
developers.amadeus.com
pbrosse@amadeus.com