Class FeatureStateModel

api/util/engine_models/features/models.py:69–124

class FeatureStateModel(BaseModel, validate_assignment=True):
    feature: FeatureModel
    enabled: bool
    django_id: typing.Optional[int] = None
    feature_segment: typing.Optional[FeatureSegmentModel] = None
    featurestate_uuid: UUID4 = Field(default_factory=uuid.uuid4)
    feature_state_value: typing.Any = None
    multivariate_feature_state_values: MultivariateFeatureStateValueList = Field(
        default_factory=MultivariateFeatureStateValueList
    )

    def set_value(self, value: typing.Any) -> None:
        self.feature_state_value = value

    def get_value(self, identity_id: typing.Union[None, int, str] = None) -> typing.Any:
        """
        Get the value of the feature state.

        :param identity_id: a unique identifier for the identity, can be either a
            numeric id or a string but must be unique for the identity.
        :return: the value of the feature state.
        """
        if identity_id and len(self.multivariate_feature_state_values) > 0:
            return self._get_multivariate_value(identity_id)
        return self.feature_state_value

    def _get_multivariate_value(
        self, identity_id: typing.Union[int, str]
    ) -> typing.Any:
        percentage_value = get_hashed_percentage_for_object_ids(
            [self.django_id or str(self.featurestate_uuid), identity_id]
        )

        # Iterate over the mv options in order of id (so we get the same value each
        # time) to determine the correct value to return to the identity based on
        # the percentage allocations of the multivariate options. This gives us a
        # way to ensure that the same value is returned every time we use the same
        # percentage value.
        start_percentage = 0.0

        def _mv_fs_sort_key(mv_value: MultivariateFeatureStateValueModel) -> SupportsLt:
            return mv_value.id or mv_value.mv_fs_value_uuid

        for mv_value in sorted(
            self.multivariate_feature_state_values,
            key=_mv_fs_sort_key,
        ):
            limit = mv_value.percentage_allocation + start_percentage
            if start_percentage <= percentage_value < limit:
                return mv_value.multivariate_feature_option.value

            start_percentage = limit

        # default to return the control value if no MV values found, although this
        # should never happen
        return self.feature_state_value  # pragma: no cover