| 45 | |
| 46 | |
| 47 | class CallbackDispatcher(object): |
| 48 | def __init__(self): |
| 49 | self._listeners = {} |
| 50 | |
| 51 | def dispatch(self, eventName, event=None): |
| 52 | if event is None: |
| 53 | event = Callback() |
| 54 | elif not isinstance(event, Callback): |
| 55 | raise ValueError('Unexpected event type given') |
| 56 | event.setName(eventName) |
| 57 | if eventName not in self._listeners: |
| 58 | return event |
| 59 | for listener in self._listeners[eventName].values(): |
| 60 | listener(event, self) |
| 61 | return event |
| 62 | |
| 63 | def addListener(self, eventName, listener, priority=0): |
| 64 | if eventName not in self._listeners: |
| 65 | self._listeners[eventName] = {} |
| 66 | self._listeners[eventName][priority] = listener |
| 67 | self._listeners[eventName] = OrderedDict(sorted(self._listeners[eventName].items(), key=lambda item: item[0])) |
| 68 | |
| 69 | def removeListener(self, eventName, listener=None): |
| 70 | if eventName not in self._listeners: |
| 71 | return |
| 72 | if not listener: |
| 73 | del self._listeners[eventName] |
| 74 | else: |
| 75 | for p, l in self._listeners[eventName].items(): |
| 76 | if l is listener: |
| 77 | self._listeners[eventName].pop(p) |
| 78 | return |
| 79 | |
| 80 | def addSubscriber(self, subscriber): |
| 81 | if not isinstance(subscriber, CallbackSubscriberInterface): |
| 82 | raise ValueError('Unexpected subscriber type given') |
| 83 | for eventName, params in subscriber.getSubscribedEvents().items(): |
| 84 | if isinstance(params, str): |
| 85 | self.addListener(eventName, getattr(subscriber, params)) |
| 86 | elif isinstance(params, list): |
| 87 | if not params: |
| 88 | raise ValueError('Invalid params "{0!r}" for event "{1!s}"'.format(params, eventName)) |
| 89 | if len(params) <= 2 and isinstance(params[0], str): |
| 90 | priority = params[1] if len(params) > 1 else 0 |
| 91 | self.addListener(eventName, getattr(subscriber, params[0]), priority) |
| 92 | else: |
| 93 | for listener in params: |
| 94 | priority = listener[1] if len(listener) > 1 else 0 |
| 95 | self.addListener(eventName, getattr(subscriber, listener[0]), priority) |
| 96 | else: |
| 97 | raise ValueError('Invalid params for event "{0!s}"'.format(eventName)) |
| 98 | |
| 99 | |