budosystems.events.message_bus

Event-driven message bus related classes and functions.

Module Attributes

EventType_contra	Event-type type variable.
AsyncEventHandler	Type alias for the signature of event handlers. In regular Python, it looks like::.
Registration	Pair of (event_type, event_handler).

Classes

MessageBus

The event message bus.

class EventType_contra

Event-type type variable. Used throughout MessageBus methods. (bound = Event)

alias of TypeVar(‘EventType_contra’, bound=Event, contravariant=True)

AsyncEventHandler

Type alias for the signature of event handlers. In regular Python, it looks like:

async def handler(event: EventOrSubtype) -> None:
    ...

alias of Callable[[EventType_contra], Awaitable[None]]

Registration

Pair of (event_type, event_handler).

alias of Tuple[Type[EventType_contra], Callable[[EventType_contra], Awaitable[None]]]