Welcome to aioevents’s documentation!

aioevents is a simple event system for asyncio. It allows objects to declare and emit events, and users to register handlers for those events.

class Spam:
    egged = Event("The spam has been egged")

a_spam = Spam()

@a_spam.egged.handler
def on_egged(sender: Spam):
    print("An egging has occurred")

a_spam.egged.trigger()

Events may have positional or keyword arguments:

@a_spam.egged.handler
def on_egged(sender: Spam, num, foo):
    print("An egging has occurred")

s_spam.egged(42, foo='bar')

Handlers can be registered at the class level, and those will receive all instance’s events:

@Spam.egged.handler
def on_egged(sender: Spam, num, foo):
    print("An egging has occurred")

more_spam = Spam()

s_spam.egged(42, foo='bar')
more_spam.egged(24, foo='baz')

Handlers may be regular functions or coroutines:

@a_spam.egged.handler
def on_egged_sync(sender, num, foo):
    print("Handling an egging")

@a_spam.egged.handler
async def on_egged_async(sender, num, foo):
    print("Handling an egging, asyncly")
    await asyncio.sleep(7)

Events may also be triggered on the class. In that case, no instance-level handlers will be called, and the first argument will be None

Contents:

Welcome to aioevents’s documentation!

Indices and tables