From e9afd17b296677b1558b83469cdf68cd3cf4e555 Mon Sep 17 00:00:00 2001 From: Jakub Trllo Date: Fri, 6 May 2022 10:02:20 +0200 Subject: [PATCH 1/4] converted event to be able create multiple independent event systems --- openpype/lib/events.py | 76 +++++++++++++++++++++++++++++++++--------- 1 file changed, 61 insertions(+), 15 deletions(-) diff --git a/openpype/lib/events.py b/openpype/lib/events.py index 7bec6ee30d3..3762cec9f91 100644 --- a/openpype/lib/events.py +++ b/openpype/lib/events.py @@ -11,6 +11,10 @@ from openpype.lib.python_2_comp import WeakMethod +class MissingEventSystem(Exception): + pass + + class EventCallback(object): """Callback registered to a topic. @@ -179,13 +183,14 @@ class Event(object): """ _data = {} - def __init__(self, topic, data=None, source=None): + def __init__(self, topic, data=None, source=None, event_system=None): self._id = str(uuid4()) self._topic = topic if data is None: data = {} self._data = data self._source = source + self._event_system = event_system def __getitem__(self, key): return self._data[key] @@ -211,28 +216,69 @@ def topic(self): def emit(self): """Emit event and trigger callbacks.""" - StoredCallbacks.emit_event(self) + if self._event_system is None: + raise MissingEventSystem( + "Can't emit event {}. Does not have set event system.".format( + str(repr(self)) + ) + ) + self._event_system.emit_event(self) -class StoredCallbacks: - _registered_callbacks = [] +class EventSystem(object): + def __init__(self): + self._registered_callbacks = [] - @classmethod - def add_callback(cls, topic, callback): + def add_callback(self, topic, callback): callback = EventCallback(topic, callback) - cls._registered_callbacks.append(callback) + self._registered_callbacks.append(callback) return callback - @classmethod - def emit_event(cls, event): + def create_event(self, topic, data, source): + return Event(topic, data, source, self) + + def emit(self, topic, data, source): + event = self.create_event(topic, data, source) + event.emit() + return event + + def emit_event(self, event): invalid_callbacks = [] - for callback in cls._registered_callbacks: + for callback in self._registered_callbacks: callback.process_event(event) if not callback.is_ref_valid: invalid_callbacks.append(callback) for callback in invalid_callbacks: - cls._registered_callbacks.remove(callback) + self._registered_callbacks.remove(callback) + + +class GlobalEvent(Event): + def __init__(self, topic, data=None, source=None): + event_system = GlobalEventSystem.get_global_event_system() + + super(GlobalEvent, self).__init__(topic, data, source, event_system) + + +class GlobalEventSystem: + _global_event_system = None + + @classmethod + def get_global_event_system(cls): + if cls._global_event_system is None: + cls._global_event_system = EventSystem() + return cls._global_event_system + + @classmethod + def add_callback(cls, topic, callback): + event_system = cls.get_global_event_system() + return event_system.add_callback(topic, callback) + + @classmethod + def emit(cls, topic, data, source): + event = GlobalEvent(topic, data, source) + event.emit() + return event def register_event_callback(topic, callback): @@ -249,7 +295,8 @@ def register_event_callback(topic, callback): enable/disable listening to a topic or remove the callback from the topic completely. """ - return StoredCallbacks.add_callback(topic, callback) + + return GlobalEventSystem.add_callback(topic, callback) def emit_event(topic, data=None, source=None): @@ -263,6 +310,5 @@ def emit_event(topic, data=None, source=None): Returns: Event: Object of event that was emitted. """ - event = Event(topic, data, source) - event.emit() - return event + + return GlobalEventSystem.emit(topic, data, source) From 8a951ee60f837dbce81442574f922691707ce614 Mon Sep 17 00:00:00 2001 From: Jakub Trllo Date: Tue, 12 Jul 2022 17:27:47 +0200 Subject: [PATCH 2/4] removed GlobalEvent --- openpype/lib/events.py | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/openpype/lib/events.py b/openpype/lib/events.py index 3762cec9f91..4a7d648a7ec 100644 --- a/openpype/lib/events.py +++ b/openpype/lib/events.py @@ -253,13 +253,6 @@ def emit_event(self, event): self._registered_callbacks.remove(callback) -class GlobalEvent(Event): - def __init__(self, topic, data=None, source=None): - event_system = GlobalEventSystem.get_global_event_system() - - super(GlobalEvent, self).__init__(topic, data, source, event_system) - - class GlobalEventSystem: _global_event_system = None @@ -276,7 +269,7 @@ def add_callback(cls, topic, callback): @classmethod def emit(cls, topic, data, source): - event = GlobalEvent(topic, data, source) + event = Event(topic, data, source, cls.get_global_event_system()) event.emit() return event From 8ab6b41db5689312c39e07426fda869d9c2cc421 Mon Sep 17 00:00:00 2001 From: Jakub Trllo Date: Tue, 12 Jul 2022 17:34:51 +0200 Subject: [PATCH 3/4] simplified global event emit --- openpype/lib/events.py | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/openpype/lib/events.py b/openpype/lib/events.py index 4a7d648a7ec..215e36bc4e4 100644 --- a/openpype/lib/events.py +++ b/openpype/lib/events.py @@ -180,7 +180,10 @@ class Event(object): topic (str): Identifier of event. data (Any): Data specific for event. Dictionary is recommended. source (str): Identifier of source. + event_system (EventSystem): Event system in which can be event + triggered. """ + _data = {} def __init__(self, topic, data=None, source=None, event_system=None): @@ -269,9 +272,8 @@ def add_callback(cls, topic, callback): @classmethod def emit(cls, topic, data, source): - event = Event(topic, data, source, cls.get_global_event_system()) - event.emit() - return event + event_system = cls.get_global_event_system() + return event_system.emit(topic, data, source) def register_event_callback(topic, callback): From 018896f9239f3fb3a036512a892a8f48593dca85 Mon Sep 17 00:00:00 2001 From: Jakub Trllo Date: Tue, 12 Jul 2022 18:28:03 +0200 Subject: [PATCH 4/4] added docstrings --- openpype/lib/events.py | 57 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/openpype/lib/events.py b/openpype/lib/events.py index 215e36bc4e4..301d62e2a6e 100644 --- a/openpype/lib/events.py +++ b/openpype/lib/events.py @@ -229,23 +229,74 @@ def emit(self): class EventSystem(object): + """Encapsulate event handling into an object. + + System wraps registered callbacks and triggered events into single object + so it is possible to create mutltiple independent systems that have their + topics and callbacks. + + + """ + def __init__(self): self._registered_callbacks = [] def add_callback(self, topic, callback): + """Register callback in event system. + + Args: + topic (str): Topic for EventCallback. + callback (Callable): Function or method that will be called + when topic is triggered. + + Returns: + EventCallback: Created callback object which can be used to + stop listening. + """ + callback = EventCallback(topic, callback) self._registered_callbacks.append(callback) return callback def create_event(self, topic, data, source): + """Create new event which is bound to event system. + + Args: + topic (str): Event topic. + data (dict): Data related to event. + source (str): Source of event. + + Returns: + Event: Object of event. + """ + return Event(topic, data, source, self) def emit(self, topic, data, source): + """Create event based on passed data and emit it. + + This is easiest way how to trigger event in an event system. + + Args: + topic (str): Event topic. + data (dict): Data related to event. + source (str): Source of event. + + Returns: + Event: Created and emitted event. + """ + event = self.create_event(topic, data, source) event.emit() return event def emit_event(self, event): + """Emit event object. + + Args: + event (Event): Prepared event with topic and data. + """ + invalid_callbacks = [] for callback in self._registered_callbacks: callback.process_event(event) @@ -257,6 +308,12 @@ def emit_event(self, event): class GlobalEventSystem: + """Event system living in global scope of process. + + This is primarily used in host implementation to trigger events + related to DCC changes or changes of context in the host implementation. + """ + _global_event_system = None @classmethod