A library implements the Mediator pattern to make your code extensible.
Inspired by symfony/event-dispatcher <https://github.com/symfony/event-dispatcher>_ component.
.. image:: https://img.shields.io/travis/Komtet/mediator.svg?style=flat-square :target: https://travis-ci.org/Komtet/mediator
Using pip:
.. code:: sh
# pip install mediatorManually:
.. code:: sh
$ git clone https://github.com/Komtet/mediator
$ cd mediator
# python setup.py install.. code:: python
from mediator import Mediator
m = Mediator().. code:: python
from mediator import Event
class EventOne(Event):
pass
class EventTwo(Event):
event_name = 'event_two'.. code:: python
def event_listener(event):
print('Got event: %r' % event)
m.add_listener(EventOne, event_listener)
# or m.add_listener('EventOne', event_listener)
m.add_listener('event_two', event_listener)
# or m.add_listener(EventTwo, event_listener).. code:: python
event1 = EventOne()
event2 = EventTwo()
m.dispatch(event1)
# Got event: <EventOne object at 0x7f954bc2b250>
m.dispatch(event2)
# Got event: <EventTwo object at 0x7f954bbbd510>.. code:: python
def another_listener(event):
print('Got another event: %r' % event)
m.add_listener(EventOne, another_listener)
m.remove_listener('EventOne', event_listener)
m.dispatch(event1)
# Got another event: <EventOne object at 0x7f954bc2b250>.. code:: python
m.remove_listener('EventOne')
m.dispatch(event1)
# Nothing was happened.. code:: python
m.add_listener('EventOne', another_listener, -255)
m.add_listener('EventOne', event_listener, 255)
m.dispatch(event1)
# Got another event: <EventOne object at 0x7f954bc2b250>
# Got event: <EventOne object at 0x7f954bc2b250>.. code:: python
from mediator import SubscriberInterface
class Subscriber(SubscriberInterface):
def first(self, event):
event.first = True
def middle(self, event):
event.middle = True
def last(self, event):
event.last = True
def event2_handler(self, event):
event.success = True
def event3_handler(self, event):
event.success = True
def get_subscribed_events(self):
return {
'event1': [
['middle'],
['first', -100],
['last', 100]
],
'event2': 'event2_handler',
'event3': ['event3_handler']
}
class Event1(Event):
event_name = 'event1'
def __init__(self):
self.first = False
self.middle = False
self.last = False
class Event2(Event):
event_name = 'event2'
def __init__(self):
self.success = True
class Event3(Event2):
event_name = 'event3'
subscriber = Subscriber()
event1 = Event1()
event2 = Event2()
event3 = Event3()
m.add_subscriber(subscriber)
m.dispatch(event1)
print('%s;%s;%s' % (event1.first, event1.middle, event1.last))
# True;True;True
m.dispatch(event2)
print(event2.success)
# True
m.dispatch(event3)
print(event3.success)
# True.. code:: python
import sys
import venusian
from mediator import VENUSIAN_CATEGORY
@SomeEvent.listen(priority=255, instance='mediator', category=VENUSIAN_CATEGORY) # All args are optional
def some_event_listener(event):
event.attr = 'value'
scanner = venusian.Scanner(mediator=mediator)
scanner.scan(package=sys.modules[__name__], categories=[VENUSIAN_CATEGORY])
m.dispatch(SomeEvent())See source code and tests for more information.
Mediator.__init__ and Mediator.scan now takes keyword arguments only.Mediator.set_scanner method.Mediator.dispatch() now takes event instances only.Mediator.add_listener and Mediator.remove_listener takes subclass of Event or str.Event.get_name() and Event.set_name() were removed in favor of Event.get_event_name() and Event.event_name class attribute.super().__init__() in your own events.Mediator.set_scanner method in order to allow use custom scanner instance.%Event%.listen decorator.The MIT License (MIT)