Class MultivariateFeatureOption

api/features/multivariate/models.py:33–112

This class holds the *value* for a given multivariate feature option. This value is the same for every environment, but the percent allocation is set in MultivariateFeatureStateValue which varies per-environment.

class MultivariateFeatureOption(
    LifecycleModelMixin,  # type: ignore[misc]
    AbstractBaseFeatureValueModel,
    AbstractBaseExportableModel,
    abstract_base_auditable_model_factory(["uuid"]),  # type: ignore[misc]
):
    """
    This class holds the *value* for a given multivariate feature
    option. This value is the same for every environment, but the
    percent allocation is set in MultivariateFeatureStateValue
    which varies per-environment.
    """

    history_record_class_path = (
        "features.multivariate.models.HistoricalMultivariateFeatureOption"
    )
    related_object_type = RelatedObjectType.FEATURE

    feature = models.ForeignKey(
        "features.Feature",
        on_delete=models.CASCADE,
        related_name="multivariate_options",
    )

    key = models.CharField(
        max_length=255,
        null=True,
        validators=[validate_slug],
        help_text="A stable, human-readable identifier for the variant.",
    )

    # This field is stored at the feature level but not used here - it is transferred
    # to the MultivariateFeatureStateValue on creation of a new option or when creating
    # a new environment.
    default_percentage_allocation = models.FloatField(
        default=100,
        validators=[MinValueValidator(0), MaxValueValidator(100)],
    )

    class Meta:
        unique_together = ("feature", "key")

    @hook(AFTER_CREATE)
    def create_multivariate_feature_state_values(self):  # type: ignore[no-untyped-def]
        for feature_state in self.feature.feature_states.filter(
            identity=None, feature_segment=None
        ):
            MultivariateFeatureStateValue.objects.create(
                feature_state=feature_state,
                multivariate_feature_option=self,
                percentage_allocation=self.default_percentage_allocation,
            )

    @hook(AFTER_CREATE)
    def make_feature_multivariate(self):  # type: ignore[no-untyped-def]
        # Handle the check on feature.type in the method itself to ensure this is
        # only performed after create. Using `when` and `is_not` means
        # LifecycleModel.__init__() queries for feature on every object init.