Contract-first design
On This Lesson 4 topics
This lesson is planned. The outline below lists the topics it will cover. The full lesson has not been published yet.
In this lesson
agree on the API shape before writing code.
Planned topics
- A contract lists URLs, methods, request and response bodies, and status codes.
- Write example requests and responses first; they are the cheapest way to find mistakes.
- Review the design with a peer or a client team before implementation.
- Changing a contract later costs more than changing a table on a whiteboard.
- The contract is not your entities: design DTOs for the client's needs.
Draft outline details
Demonstration
one table row plus examples
POST /products body {"name","priceCents","categoryId"}
201 Location: /products/5 body {"id":5,"name":"Pen",...}
400 {"type":"...","title":"Invalid request"}Check your understanding
What is reviewed before implementation?
Show answer
The contract: endpoints, bodies, status codes.
Practice
Apply this lesson with the module's lab, exercises and quiz.
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