[Bug]: forcebool inconsistency with BooleanCaster

[indigane]

Actual Behavior

I have API tests similar to the one below that test 'True', 'true' and '1' for a boolean query parameter.

openapi-core/tests/unit/test_util.py

Lines 6 to 22 in b8f0644

	class TestForcebool:
	@pytest.mark.parametrize("val", ["y", "yes", "t", "true", "on", "1", True])
	def test_true(self, val):
	result = forcebool(val)
	assert result is True
	@pytest.mark.parametrize(
	"val", ["n", "no", "f", "false", "off", "0", False]
	)
	def test_false(self, val):
	result = forcebool(val)
	assert result is False
	@pytest.mark.parametrize("val", ["random", "idontknow", ""])
	def test_value_error(self, val):
	with pytest.raises(ValueError):
	forcebool(val)

The last one, '1', no longer passes validation.

Expected Behavior

This behavior has changed at some point after 0.16.x where the test passed. This came up attempting to update past 0.16.x where the test started failing due to CastingError.

As for expected behavior, it may be that the new behavior is more correct but it is also somewhat common to allow '1' in APIs.

The older versions used forcebool as the caster/validator but the current version first calls BooleanCaster.validate before calling forcebool.

Steps to Reproduce

Pass for example '1' to BooleanCaster.__call__.

OpenAPI Core Version

0.19.2

OpenAPI Core Integration

django

Affected Area(s)

casting, validation

References

Old code:

openapi-core/openapi_core/casting/schemas/factories.py

Lines 19 to 23 in efaa5ac

	PRIMITIVE_CASTERS: Dict[str, CasterCallable] = {
	"integer": int,
	"number": float,
	"boolean": forcebool,
	}

openapi-core/openapi_core/util.py

Lines 7 to 17 in efaa5ac

	def forcebool(val: Any) -> bool:
	if isinstance(val, str):
	val = val.lower()
	if val in ("y", "yes", "t", "true", "on", "1"):
	return True
	elif val in ("n", "no", "f", "false", "off", "0"):
	return False
	else:
	raise ValueError(f"invalid truth value {val!r}")
	return bool(val)

Current code:

openapi-core/openapi_core/casting/schemas/__init__.py

Lines 25 to 34 in b8f0644

	oas30_casters_dict = OrderedDict(
	[
	("object", ObjectCaster),
	("array", ArrayCaster),
	("boolean", BooleanCaster),
	("integer", IntegerCaster),
	("number", NumberCaster),
	("string", PrimitiveCaster),
	]
	)

openapi-core/openapi_core/casting/schemas/casters.py

Lines 61 to 78 in 8e2c5a8

	class BooleanCaster(PrimitiveTypeCaster[bool]):
	primitive_type = bool
	def __call__(self, value: Union[str, bytes]) -> Any:
	self.validate(value)
	return self.primitive_type(forcebool(value))
	def validate(self, value: Any) -> None:
	super().validate(value)
	# FIXME: don't cast data from media type deserializer
	# See https://github.com/python-openapi/openapi-core/issues/706
	if isinstance(value, bool):
	return
	if value.lower() not in ["false", "true"]:
	raise ValueError("not a boolean format")

Anything else we need to know?

The main thing I want to point out is that forcebool is only ever called after validate which means that values other than 'true' and 'false' can never get to forcebool.

If this is on purpose, then I assume the way around this is to provide a custom BooleanCaster?

Or are there other suggested solutions if I do want to allow '1' in the API?

Would you like to implement a fix?

None