azizhamza-code/python_ddd_tdd

Layered architecture :

• Presentation Layer
• Business Layer
• Data Access Layer

Layered architecture:

• Presentation Layer
  • This might be:
    • A web application
    • An API
• Business Layer
  • Contains:
    • Business logic
    • Business rules
• Data Access Layer

This model could be implemented by using one simple principle: dependency inversion principle.

With a formal definition:

• High-level modules should not depend on low-level modules. Both should depend on abstractions.
• Abstractions should not depend on details. Details should depend on abstractions.

depends on means in this case that one model knows about or needs another module.