53 lines
1.4 KiB
ReStructuredText
53 lines
1.4 KiB
ReStructuredText
Event system
|
|
============
|
|
|
|
Generic library provides ``generic.event`` module which helps you implement
|
|
event systems in your application. By event system I mean an API for
|
|
*subscribing* for some types of events and to *handle* those events so previously
|
|
subscribed *handlers* are being executed.
|
|
|
|
.. contents::
|
|
:local:
|
|
|
|
Basic usage
|
|
-----------
|
|
|
|
First you need to describe event types you want to use in your application,
|
|
``generic.event`` dispatches events to corresponding handlers by inspecting
|
|
events' types, so it's natural to model those as classes::
|
|
|
|
>>> class CommentAdded(object):
|
|
... def __init__(self, post_id, comment):
|
|
... self.post_id = post_id
|
|
... self.comment = comment
|
|
|
|
Now you want to register handler for your event type::
|
|
|
|
>>> from generic.event import Manager
|
|
|
|
>>> manager = Manager()
|
|
|
|
>>> @manager.subscriber(CommentAdded)
|
|
... def print_comment(ev):
|
|
... print(f"Got new comment: {ev.comment}")
|
|
|
|
Then you just call ``generic.event.handle`` function with ``CommentAdded``
|
|
instance as its argument::
|
|
|
|
>>> manager.handle(CommentAdded(167, "Hello!"))
|
|
Got new comment: Hello!
|
|
|
|
This is how it works.
|
|
|
|
Event inheritance
|
|
-----------------
|
|
|
|
Using per-application event API
|
|
-------------------------------
|
|
|
|
API reference
|
|
-------------
|
|
|
|
.. autoclass:: generic.event.Manager
|
|
:members: subscribe, subscriber, handle, unsubscribe
|