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Outbound Port

_outbound_port

Outbound port contracts — the driven side of hexagonal architecture.

Outbound ports are called by the application core out to infrastructure.
They define the boundary where the application depends on external services.

OutboundPort

Bases: Port

ABC for outbound port contracts.

Responsibilities
  • Define the driven-side boundary of the application core.
  • Enforce that concrete outbound ports do not depend on inbound
    ports via __init_subclass__ validation.
Non-Responsibilities
  • Does NOT perform structural duck-typing — returns
    NotImplemented from __subclasshook__.
Example 
class UserRepositoryPort(OutboundPort):
    def save(self, name: str) -> str: ...


# __init_subclass__ validates that __init__
# parameters are OutboundPorts, never InboundPorts.
Source code in src/forging_blocks/foundation/ports/_outbound_port.py 
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class OutboundPort(Port):
    """ABC for outbound port contracts.

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

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

    Example:
        ```python
        class UserRepositoryPort(OutboundPort):
            def save(self, name: str) -> str: ...


        # __init_subclass__ validates that __init__
        # parameters are OutboundPorts, never InboundPorts.
        ```
    """

    @classmethod
    @runtime_final
    def __init_subclass__(cls, /) -> None:
        """ """
        super().__init_subclass__()
        if not AbstractPortClassifier(cls).is_abstract():
            OutboundDependencyValidator(cls, target_port=InboundPort).validate()

__init_subclass__() -> None classmethod

Source code in src/forging_blocks/foundation/ports/_outbound_port.py 
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@classmethod
@runtime_final
def __init_subclass__(cls, /) -> None:
    """ """
    super().__init_subclass__()
    if not AbstractPortClassifier(cls).is_abstract():
        OutboundDependencyValidator(cls, target_port=InboundPort).validate()