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hololinked.core.thing.ThingMeta

Bases: ParameterizedMetaclass

Metaclass for Thing, implements a __post_init__() call and instantiation of a registry for properties', actions' and events' descriptor objects. Accessing properties, actions and events at the class level returns the descriptor object through the DescriptorRegistry implementation. Accessing properties, actions and events at instance level return their values (for example - the value of Property foo being 5). __post_init__() is run after the user's __init__() method, properties that can be loaded from a database are loaded and written at this time. Overload __post_init__() in subclasses to add additional functionality.

UML Diagram

Source code in hololinked/hololinked/core/meta.py 
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class ThingMeta(ParameterizedMetaclass):
    """
    Metaclass for `Thing`, implements a `__post_init__()` call and instantiation of a registry for properties', actions'
    and events' descriptor objects.
    Accessing properties, actions and events at the class level returns the descriptor object through the `DescriptorRegistry`
    implementation. Accessing properties, actions and events at instance level return their values (for example -
    the value of Property `foo` being `5`).
    `__post_init__()` is run after the user's `__init__()` method, properties that can be
    loaded from a database are loaded and written at this time. Overload `__post_init__()` in subclasses
    to add additional functionality.

    [UML Diagram](https://docs.hololinked.dev/UML/PDF/Thing.pdf)
    """

    def __init__(mcs, name, bases, dict_):
        super().__init__(name, bases, dict_)
        mcs._create_actions_registry()
        mcs._create_events_registry()

    def __call__(mcls, *args, **kwargs):
        instance = super().__call__(*args, **kwargs)
        instance.__post_init__()
        return instance

    def _create_param_container(cls, cls_members: dict) -> None:
        """
        creates `PropertiesRegistry` instead of `param`'s own `Parameters`
        as the default container for descriptors. All properties have definitions
        copied from `param`.
        """
        cls._param_container = PropertiesRegistry(cls, cls_members)

    def _create_actions_registry(cls) -> None:
        """
        creates `Actions` instead of `param`'s own `Parameters`
        as the default container for descriptors. All actions have definitions
        copied from `param`.
        """
        cls._actions_registry = ActionsRegistry(cls)

    def _create_events_registry(cls) -> None:
        """
        creates `Events` instead of `param`'s own `Parameters`
        as the default container for descriptors. All events have definitions
        copied from `param`.
        """
        cls._events_registry = EventsRegistry(cls)

    @property
    def properties(cls) -> "PropertiesRegistry":
        """
        Container object for Property descriptors. Returns `PropertiesRegistry`
        instance instead of `param`'s own `Parameters` instance.
        """
        return cls._param_container

    @property
    def actions(cls) -> "ActionsRegistry":
        """Container object for Action descriptors"""
        return cls._actions_registry

    @property
    def events(cls) -> "EventsRegistry":
        """Container object for Event descriptors"""
        return cls._events_registry

Attributes

actions property 

actions: ActionsRegistry

Container object for Action descriptors

events property 

events: EventsRegistry

Container object for Event descriptors

properties property 

properties: PropertiesRegistry

Container object for Property descriptors. Returns PropertiesRegistry instance instead of param's own Parameters instance.