Events
Event Handlers
An event handler is an async function which you define and register with the app to
handle certain classes of events. It is passed the instance of the event, and handlers
are able to modify it for future handlers if they wish.
For example:
@app.listen(events.Receive)
async def echo(event: events.Receive):
event.client.write(event.data)
Multiple handlers can listen to a single event; they will be called in the order they
are defined. If a handler does not want later handlers to receive the event, it can call
event.stop().
Events also are bubbled up to superclass handlers - see Event inheritance for more details.
Event inheritance
It is often desirable to bind a handler to listen to a category of events; for example, if you want to extend all client events by adding a user attribute.
To make this easy, Mara lets you bind a handler to an event base class. For
example, a handler bound to events.Client will also be called for
Receive, Connect and Disconnect events.
The order that handlers are bound is still respected.
Writing custom events
Create a subclass of mara.events.Event and ensure it sets a docstring
or __str__ for logging.
Handlers are matched by comparing classes, so you can have two classes with the same name (as long as they are in separate modules).