Skip to content

Inbound Port

_inbound_port

Inbound port contracts — the driving side of hexagonal architecture.

Inbound ports are called by infrastructure into the application core.
They define the boundary where external actors invoke application logic.

InboundPort

Bases: Port

ABC for inbound port contracts.

Responsibilities
  • Define the driving-side boundary of the application core.
  • Enforce that concrete inbound ports do not depend on other
    inbound ports via __init_subclass__ validation.
Non-Responsibilities
  • Does NOT perform structural duck-typing — returns
    NotImplemented from __subclasshook__.
Example 
class CreateUserPort(InboundPort):
    def __init__(self, repo: "OutboundPort") -> None: ...

    def execute(self, name: str) -> str: ...


# __init_subclass__ validates that every __init__
# parameter is an OutboundPort, never an InboundPort.
Source code in src/forging_blocks/foundation/ports/_inbound_port.py 
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
class InboundPort(Port):
    """ABC for inbound port contracts.

    Responsibilities:
        - Define the driving-side boundary of the application core.
        - Enforce that concrete inbound ports do not depend on other
          inbound ports via ``__init_subclass__`` validation.

    Non-Responsibilities:
        - Does NOT perform structural duck-typing — returns
          ``NotImplemented`` from ``__subclasshook__``.

    Example:
        ```python
        class CreateUserPort(InboundPort):
            def __init__(self, repo: "OutboundPort") -> None: ...

            def execute(self, name: str) -> str: ...


        # __init_subclass__ validates that every __init__
        # parameter is an OutboundPort, never an InboundPort.
        ```
    """

    @classmethod
    @runtime_final
    def __init_subclass__(cls, /) -> None:
        """ """
        super().__init_subclass__()

        if not AbstractPortClassifier(cls).is_abstract():
            InboundDependencyValidator(cls, target_port=InboundPort).validate()

__init_subclass__() -> None classmethod

Source code in src/forging_blocks/foundation/ports/_inbound_port.py 
43
44
45
46
47
48
49
50
@classmethod
@runtime_final
def __init_subclass__(cls, /) -> None:
    """ """
    super().__init_subclass__()

    if not AbstractPortClassifier(cls).is_abstract():
        InboundDependencyValidator(cls, target_port=InboundPort).validate()