def __init__(self, event_callback, unsubscribe_callback, period=0.5): QtCore.QThread.__init__(self) self.listeners = CaselessDict() self.inverse_listeners = {} self.event_callback = event_callback self.unsubscribe_callback = unsubscribe_callback self.period = period self._attributes = CaselessList() self._config = CaselessDict() self._last_event = TTLDict(default_ttl=10) self.attribute_validator = TangoAttributeNameValidator() self.device_validator = TangoDeviceNameValidator() self.eval_validator = EvaluationAttributeNameValidator() self.lock = Lock() self.stopped = Event()
def run(self): "A simple loop checking for changes to the attribute list" # "batching" the updates should be more efficient than # reacting immediately, especially when listeners can come and # go quite frequently. while not self.stopped.is_set(): sleep(self.period) if self._attributes: attributes, self._attributes = self._attributes, CaselessList() with self.lock: self._update(attributes)
class Registry(QtCore.QThread): """ A thread that handles attribute subscriptions. The main purpose of this thread is to offload the setting up and tearing down of subscriptions from the main UI thread, to make the operation "asynchronous". We don't want the UI to lock up briefly every time we do this (which may be very often in the case of a large, zoomable synoptic). """ def __init__(self, event_callback, unsubscribe_callback, period=0.5): QtCore.QThread.__init__(self) self.listeners = CaselessDict() self.inverse_listeners = {} self.event_callback = event_callback self.unsubscribe_callback = unsubscribe_callback self.period = period self._attributes = CaselessList() self._config = CaselessDict() self._last_event = TTLDict(default_ttl=10) self.attribute_validator = TangoAttributeNameValidator() self.device_validator = TangoDeviceNameValidator() self.eval_validator = EvaluationAttributeNameValidator() self.lock = Lock() self.stopped = Event() def run(self): "A simple loop checking for changes to the attribute list" # "batching" the updates should be more efficient than # reacting immediately, especially when listeners can come and # go quite frequently. while not self.stopped.is_set(): sleep(self.period) if self._attributes: attributes, self._attributes = self._attributes, CaselessList() with self.lock: self._update(attributes) def subscribe(self, models=[]): """Set the currently subscribed list of models.""" attrs = CaselessDict() for model in models: if self.device_validator.isValid(model): # for convenience, we subscribe to State for any devices attrs[model + "/State"] = True elif self.attribute_validator.isValid(model) or self.eval_validator.isValid(model): attrs[model] = True else: print "Invalid Taurus model %s!?" % model self._attributes = attrs def get_value(self, model): evt = self._last_event.get(model) if evt: return evt.attr_value def get_config(self, model): return self._config.get(model) def handle_event(self, evt_src, *args): # lookup the model(s) for this listener and notify them models = self.inverse_listeners.get(evt_src, []) for model in models: self.event_callback(model, evt_src, *args) def _update(self, attributes=CaselessDict()): "Update the subscriptions; add new ones, remove old ones" listeners = set(k.lower() for k in self.listeners.keys()) new_attrs = set(attributes) - set(listeners) old_attrs = set(listeners) - set(attributes) for attr in old_attrs: if self._attributes: # meaning we got a new list of subscriptions, so # no point in continuing with this one. return self._remove_listener(attr) self._last_event.pop(attr, None) for attr in new_attrs: if self._attributes: return try: self._add_listener(attr) except PyTango.DevFailed as e: print "Failed to setup listener for", attr, e self.unsubscribe_callback(old_attrs) def _add_listener(self, model): try: listener = self.listeners[model] = Attribute(model) # to make loopkups more efficient, we also keep an "inverted" # mapping of listeners->models. But since some models may map # to the *same* listener (e.g. eval expressions), this must # be a one-to-many map. if listener in self.inverse_listeners: self.inverse_listeners[listener][model] = True else: self.inverse_listeners[listener] = CaselessDict([(model, True)]) listener.addListener(self.handle_event) return listener except AttributeError: print "Failed to subscribe to model %s!" % model def _remove_listener(self, model): listener = self.listeners.pop(model) models = self.inverse_listeners[listener] print models, model models.pop(model) if not models: self.inverse_listeners.pop(listener) listener.removeListener(self.handle_event) def get_listener(self, model): "return the listener for a given model" if model in self.listeners: return self.listeners[model] for attr in self.listeners.values(): if attr.getNormalName().lower() == model.lower(): return attr def stop(self): self.stopped.set() def clear(self): self._attributes.clear() self._last_event.clear() self._update()
class Registry(QtCore.QThread): """ A thread that handles attribute subscriptions. The main purpose of this thread is to offload the setting up and tearing down of subscriptions from the main UI thread, to make the operation "asynchronous". We don't want the UI to lock up briefly every time we do this (which may be very often in the case of a large, zoomable synoptic). """ def __init__(self, event_callback, unsubscribe_callback, period=0.5): QtCore.QThread.__init__(self) self.listeners = CaselessDict() self.inverse_listeners = {} self.event_callback = event_callback self.unsubscribe_callback = unsubscribe_callback self.period = period self._attributes = CaselessList() self._config = CaselessDict() self._last_event = TTLDict(default_ttl=10) self.attribute_validator = TangoAttributeNameValidator() self.device_validator = TangoDeviceNameValidator() self.eval_validator = EvaluationAttributeNameValidator() self.lock = Lock() self.stopped = Event() def run(self): "A simple loop checking for changes to the attribute list" # "batching" the updates should be more efficient than # reacting immediately, especially when listeners can come and # go quite frequently. while not self.stopped.is_set(): sleep(self.period) if self._attributes: attributes, self._attributes = self._attributes, CaselessList() with self.lock: self._update(attributes) def subscribe(self, models=[]): """Set the currently subscribed list of models.""" attrs = CaselessDict() for model in models: if self.device_validator.isValid(model): # for convenience, we subscribe to State for any devices attrs[model + "/State"] = True elif (self.attribute_validator.isValid(model) or self.eval_validator.isValid(model)): attrs[model] = True else: print "Invalid Taurus model %s!?" % model self._attributes = attrs def get_value(self, model): evt = self._last_event.get(model) if evt: return evt.attr_value def get_config(self, model): return self._config.get(model) def handle_event(self, evt_src, *args): # lookup the model(s) for this listener and notify them models = self.inverse_listeners.get(evt_src, []) for model in models: self.event_callback(model, evt_src, *args) def _update(self, attributes=CaselessDict()): "Update the subscriptions; add new ones, remove old ones" listeners = set(k.lower() for k in self.listeners.keys()) new_attrs = set(attributes) - set(listeners) old_attrs = set(listeners) - set(attributes) for attr in old_attrs: if self._attributes: # meaning we got a new list of subscriptions, so # no point in continuing with this one. return self._remove_listener(attr) self._last_event.pop(attr, None) for attr in new_attrs: if self._attributes: return try: self._add_listener(attr) except PyTango.DevFailed as e: print "Failed to setup listener for", attr, e self.unsubscribe_callback(old_attrs) def _add_listener(self, model): try: listener = self.listeners[model] = Attribute(model) # to make loopkups more efficient, we also keep an "inverted" # mapping of listeners->models. But since some models may map # to the *same* listener (e.g. eval expressions), this must # be a one-to-many map. if listener in self.inverse_listeners: self.inverse_listeners[listener][model] = True else: self.inverse_listeners[listener] = CaselessDict([(model, True)]) listener.addListener(self.handle_event) return listener except AttributeError: print "Failed to subscribe to model %s!" % model def _remove_listener(self, model): listener = self.listeners.pop(model) models = self.inverse_listeners[listener] print models, model models.pop(model) if not models: self.inverse_listeners.pop(listener) listener.removeListener(self.handle_event) def get_listener(self, model): "return the listener for a given model" if model in self.listeners: return self.listeners[model] for attr in self.listeners.values(): if attr.getNormalName().lower() == model.lower(): return attr def stop(self): self.stopped.set() def clear(self): self._attributes.clear() self._last_event.clear() self._update()