lifecycle

@dataclass
class Persistent(TraitBase):
    """Persistent trait model.

    Persistent trait is opposite to transient trait. It marks representation
    as persistent. Such representations are persisted in the system (e.g. in
    the database).

    Attributes:
        name (str): Trait name.
        description (str): Trait description.
        id (str): id should be a namespaced trait name with the version
    """

    name: ClassVar[str] = "Persistent"
    description: ClassVar[str] = "Persistent Trait Model"
    id: ClassVar[str] = "ayon.lifecycle.Persistent.v1"
    # Note that this affects the persistence of the trait itself, not
    # the representation. This is a class variable, so it is shared
    # among all instances of the class.
    persistent: bool = True

    def validate_trait(self, representation) -> None:  # noqa: ANN001
        """Validate representation is not Transient.

        Args:
            representation (Representation): Representation model.

        Raises:
            TraitValidationError: If representation is marked
                as both Persistent and Transient.

        """
        if representation.contains_trait(Transient):
            msg = "Representation is marked as both Persistent and Transient."
            raise TraitValidationError(self.name, msg)

@dataclass
class Transient(TraitBase):
    """Transient trait model.

    Transient trait marks representation as transient. Such representations
    are not persisted in the system.

    Attributes:
        name (str): Trait name.
        description (str): Trait description.
        id (str): id should be a namespaced trait name with the version
    """

    name: ClassVar[str] = "Transient"
    description: ClassVar[str] = "Transient Trait Model"
    id: ClassVar[str] = "ayon.lifecycle.Transient.v1"
    persistent: ClassVar[bool] = True  # see note in Persistent

    def validate_trait(self, representation) -> None:  # noqa: ANN001
        """Validate representation is not Persistent.

        Args:
            representation (Representation): Representation model.

        Raises:
            TraitValidationError: If representation is marked as both
                Persistent and Transient.

        """
        if representation.contains_trait(Persistent):
            msg = "Representation is marked as both Persistent and Transient."
            raise TraitValidationError(self.name, msg)