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()
def get_changes(data, calls):
"""Combine a list of database calls into "changes" that can
be more easily turned into a readable representation"""
devices = get_devices_from_dict(data["servers"])
device_mapping = CaselessDict(
(device, (server, instance, clss))
for server, instance, clss, device in devices)
classes = data.get("classes", {})
# The idea is to first go through all database calls and collect
# the changes per device. Then we can print it all out in a more
# readable format since it will all be collected per device.
#
# Example of resulting dict:
# {
# "sys/tg_test/1": {
# "server": "TangoTest",
# "instance": "test",
# "device_class": "TangoTest",
# "properties": {
# # added property has no old_value
# "hej": {
# "value": ["a", "b", "c"]
# },
# # removed property has no value
# "svej": {
# "old_value": ["dsaodkasokd"]
# },
# # changed property has both
# "flepp": {
# "old_value": ["1", "3"],
# "value": ["1", "2", "3"]
# }
# }
# }
# }
changes = {"devices": SetterDict(), "classes": SetterDict()}
# Go through all database calls and store the changes
for method, args, kwargs in calls:
if method == "put_device_alias":
device, alias = args
if device in device_mapping:
old_alias = get_device_data(device, device_mapping,
data).get("alias")
else:
old_alias = None
changes["devices"][device].update(
{"alias": {
"old_value": old_alias,
"value": alias
}})
elif method == "add_device":
info, = args
changes["devices"][info.name].update(added=True,
server=info.server,
device_class=info._class)
if info.name in device_mapping:
old_server, old_instance, old_class = device_mapping[info.name]
changes["devices"][info.name]["old_server"] = "{}/{}".format(
old_server, old_instance)
changes["devices"][info.name]["old_class"] = old_class
elif method == "delete_device":
device, = args
server, instance, clss = device_mapping[device]
device_data = data["servers"][server][instance][clss]
properties = device_data.get("properties", {})
changes["devices"][device].update(deleted=True,
server="{}/{}".format(
server, instance),
instance=instance,
device_class=clss,
properties=properties)
elif method == "put_device_property":
device, properties = args
old_data = get_device_data(device, device_mapping, data)
caseless_props = CaselessDict(old_data.get("properties", {}))
if "properties" not in changes["devices"][device]:
changes["devices"][device]["properties"] = {}
for name, value in properties.items():
old_value = caseless_props.get(name)
if value != old_value:
changes["devices"][device]["properties"].update(
{name: {
"value": value,
"old_value": old_value
}})
elif method == "delete_device_property":
device, properties = args
old_data = get_device_data(device, device_mapping, data)
caseless_props = CaselessDict(old_data.get("properties", {}))
prop_changes = changes["devices"][device].setdefault(
"properties", {})
for prop in properties:
old_value = caseless_props[prop]
prop_changes[prop] = {"old_value": old_value}
elif method == "put_device_attribute_property":
device, properties = args
attr_props = changes["devices"][device].setdefault(
"attribute_properties", {})
old_data = get_device_data(device, device_mapping, data)
caseless_attrs = CaselessDict(
old_data.get("attribute_properties", {}))
for attr, props in properties.items():
caseless_props = CaselessDict(caseless_attrs.get(attr, {}))
for name, value in props.items():
old_value = caseless_props.get(name)
if value != old_value:
attr_props[attr] = {
name: {
"old_value": old_value,
"value": value
}
}
elif method == "delete_device_attribute_property":
device, attributes = args
prop_changes = attr_props = changes["devices"][device].setdefault(
"attribute_properties", {})
old_data = get_device_data(device, device_mapping, data)
caseless_attrs = CaselessDict(
old_data.get("attribute_properties", {}))
for attr, props in attributes.items():
caseless_props = CaselessDict(caseless_attrs[attr])
for prop in props:
old_value = caseless_props.get(prop)
attr_props[attr] = {prop: {"old_value": old_value}}
elif method == "put_class_property":
clss, properties = args
old_data = classes.get(clss, {})
caseless_props = CaselessDict(old_data.get("properties", {}))
prop_changes = changes["classes"][clss].setdefault(
"properties", {})
for name, value in properties.items():
old_value = caseless_props.get(name)
if value != old_value:
prop_changes.update(
{name: {
"value": value,
"old_value": old_value
}})
elif method == "delete_class_property":
clss, properties = args
old_data = classes.get(clss, {})
caseless_props = CaselessDict(old_data.get("properties", {}))
prop_changes = changes["classes"][clss].setdefault(
"properties", {})
for prop in properties:
old_value = caseless_props.get(prop)
prop_changes[prop] = {"old_value": old_value}
elif method == "put_class_attribute_property":
clss, properties = args
attr_props = changes["classes"][clss].setdefault(
"attribute_properties", {})
old_data = classes.get(clss, {})
caseless_attrs = CaselessDict(
old_data.get("attribute_properties", {}))
for attr, props in properties.items():
caseless_props = CaselessDict(caseless_attrs.get(attr, {}))
for name, value in props.items():
old_value = caseless_props.get(name)
if value != old_value:
attr_props[attr] = {
name: {
"old_value": old_value,
"value": value
}
}
elif method == "delete_class_attribute_property":
clss, attributes = args
attr_props = changes["classes"][clss].setdefault(
"attribute_properties", {})
old_data = classes.get(clss, {})
caseless_attrs = CaselessDict(old_data.get("properties", {}))
for attr, props in attributes.items():
caseless_props = CaselessDict(caseless_attrs.get(attr, {}))
for prop in props:
old_value = caseless_props.get(prop)
attr_props[attr] = {prop: {"old_value": old_value}}
return {
"devices": changes["devices"].to_dict(),
"classes": changes["classes"].to_dict(),
}
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()