02.04.05 — BusinessInvariantValidator vs FrameworkInvariantValidator#

class _BaseCustomInvariantValidator:
    @staticmethod
    def create[T](
        value: T,
        name: str,
        build_chain: Callable[[ValidationStartBlock[T], T], ValidationAssertBlock[T]],
    ) -> ValidationAssertBlock[T]:
        return _create_business_invariant_validator(
            value, name, lambda chain: build_chain(chain, value)
        )


@final
class BusinessInvariantValidator(_BaseCustomInvariantValidator):
    """Factory for creating business domain invariant validators.

    Use this for domain-specific validation logic (e.g., "user must be adult",
    "order total must match items").
    """


@final
class FrameworkInvariantValidator(_BaseCustomInvariantValidator):
    """Factory for creating framework-level invariant validators.

    Use this for technical/framework validation logic (e.g., "config must be valid",
    "test structure must be correct").
    """

def _create_business_invariant_validator[T](
    value: T,
    name: str,
    build_chain: ValidationChainBuilder[T],
) -> ValidationAssertBlock[T]:
    start_block = validate(value, name=name)
    return build_chain(start_block)

# src/ocarina/custom_invariants/testing/workers.py
from ocarina.dsl.invariants.assertions import is_not_zero, is_positive
from ocarina.dsl.invariants.validate import FrameworkInvariantValidator


def _workers_amount_chain(
    chain: ValidationStartBlock[int],
    value: int,
) -> ValidationAssertBlock[int]:
    msg = f"Value Error: Number of workers must be at least 1 (got: {value})."
    return chain.assert_that(is_positive, msg=msg).assert_that(is_not_zero, msg=msg)


def validate_workers_amount(
    *, workers_amount: int, name: str
) -> ValidationAssertBlock[int]:
    """Validate that workers amount is at least 1."""
    return FrameworkInvariantValidator.create(
        workers_amount, name, _workers_amount_chain
    )