Handlers

diffusion.handlers

Base module for various event handlers.

Handler

Bases: Protocol

Protocol for event handlers implementation.

handle async

handle(event: str, **kwargs: typing.Any) -> typing.Any

Implements handling of the given event.

Parameters:

Name	Type	Description	Default
event	str	The event identifier.	required
**kwargs	typing.Any	Additional arguments.	{}

remove

remove(sub_handler: Handler) -> None

Removes the given sub-handler from the given handler.

Raises:

Type	Description
KeyError	If the handler does not exist.

UnknownHandlerError

Bases: exceptions.DiffusionError

Raised when a requested handler key has not been registered in the session.

SimpleHandler

Bases: Handler

Wraps a callable into a Handler protocol instance.

handle async

handle(event: str = '', **kwargs: typing.Any) -> typing.Any

Implements handling of the given event.

Parameters:

Name	Type	Description	Default
event	str	The event identifier.	''
**kwargs	typing.Any	Additional arguments.	{}

AbstractHandlerSet

Bases: Handler, typing.Iterable[Handler], abc.ABC

handle async

handle(event: str = '', **kwargs: typing.Any) -> typing.Any

Implements handling of the given event.

Parameters:

Name	Type	Description	Default
event	str	The event identifier.	''
**kwargs	typing.Any	Additional arguments.	{}

Returns:

Type	Description
typing.Any	Aggregated list of returned values.

HandlerSet

Bases: set, AbstractHandlerSet

A collection of handlers to be invoked together.

EventStreamHandler

Bases: Handler

Generic handler of event streams.

Each keyword argument is a callable which will be converted to coroutine and awaited to handle the event matching the argument keyword.

handle async

handle(event: str, **kwargs: typing.Any) -> typing.Any

Implements handling of the given event.

Parameters:

Name	Type	Description	Default
event	str	The event identifier.	required
**kwargs	typing.Any	Additional arguments.	{}