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