Metaclasses

The Metaclass allow customization of Thing subclass creation, modify class attributes, and enforce certain behaviors across multiple Thing classes. It is mainly intended for grouping class definition for same hardware types.

default metaclass implements:

• creation of descriptor registries at class level (so that registries can also be used without instances)
• __post_init__ method to allow for code that should run post initialization of the class

Subclassing metaclasses can implement:

• mandate existence of certain properties, actions, or events according to the hardware type
• also constrain the type of the properties, payload schema of actions, or events
• default code to run when an instance is created