#!/usr/bin/env python
# -*- coding: utf-8 -*-
# ###########################################################################
#
# This file is part of Taurus
#
# http://taurus-scada.org
#
# Copyright 2011 CELLS / ALBA Synchrotron, Bellaterra, Spain
#
# Taurus is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Taurus is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Taurus. If not, see <http://www.gnu.org/licenses/>.
#
# ###########################################################################
"""This module contains all taurus tango attribute
"""
import re
import time
import threading
import weakref
import PyTango
import numpy
from functools import partial
from taurus import Manager
from taurus.core.units import Quantity, UR
from taurus import tauruscustomsettings
from taurus.core.taurusattribute import TaurusAttribute
from taurus.core.taurusbasetypes import (
TaurusEventType,
TaurusSerializationMode,
SubscriptionState,
TaurusAttrValue,
DataFormat,
DataType,
)
from taurus.core.taurusoperation import WriteAttrOperation
from taurus.core.util.event import EventListener, _BoundMethodWeakrefWithCall
from taurus.core.util.log import (
debug,
taurus4_deprecation,
deprecation_decorator,
)
from taurus.core.tango.enums import (
EVENT_TO_POLLING_EXCEPTIONS,
FROM_TANGO_TO_NUMPY_TYPE,
DevState,
)
from .util.tango_taurus import (
description_from_tango,
display_level_from_tango,
quality_from_tango,
standard_display_format_from_tango,
quantity_from_tango_str,
data_format_from_tango,
data_type_from_tango,
)
__docformat__ = "restructuredtext"
[docs]class TangoAttrValue(TaurusAttrValue):
"""A TaurusAttrValue specialization to decode PyTango.DeviceAttribute
objects
"""
def __init__(self, attr=None, pytango_dev_attr=None, config=None):
# config parameter is kept for backwards compatibility only
TaurusAttrValue.__init__(self)
if config is not None:
from taurus.core.util.log import deprecated
deprecated(dep='"config" kwarg', alt='"attr"', rel="4.0")
attr = config
if attr is None:
self._attrRef = None
self.__attrType = None
else:
self._attrRef = weakref.proxy(attr)
self.__attrName = attr.getFullName()
self.__attrType = attr.type
self.config = self._attrRef # bck-compat
self._pytango_dev_attr = p = pytango_dev_attr
if p is None:
self._pytango_dev_attr = p = PyTango.DeviceAttribute()
return
if self._attrRef is None:
return
numerical = PyTango.is_numerical_type(
self._attrRef._tango_data_type, inc_array=True
)
if p.has_failed:
self.error = PyTango.DevFailed(*p.get_err_stack())
else:
# spectra and images can be empty without failing
if p.is_empty and self._attrRef.data_format != DataFormat._0D:
dtype = FROM_TANGO_TO_NUMPY_TYPE.get(
self._attrRef._tango_data_type
)
if self._attrRef.data_format == DataFormat._1D:
shape = (0,)
elif self._attrRef.data_format == DataFormat._2D:
shape = (0, 0)
p.value = numpy.empty(shape, dtype=dtype)
if not (numerical or self._attrRef.type == DataType.Boolean):
# generate a nested empty list of given shape
p.value = []
for _ in range(len(shape) - 1):
p.value = [p.value]
# Protect against DeviceAttribute not providing .value in some cases,
# seen e.g. in PyTango 9.3.0
rvalue = getattr(p, "value", None)
wvalue = getattr(p, "w_value", None)
if numerical:
units = self._attrRef._units
if rvalue is not None:
rvalue = Quantity(rvalue, units=units)
if wvalue is not None:
wvalue = Quantity(wvalue, units=units)
elif isinstance(rvalue, PyTango._PyTango.DevState):
rvalue = DevState[str(rvalue)]
self.rvalue = rvalue
self.wvalue = wvalue
self.time = p.time # TODO: decode this into a TaurusTimeVal
self.quality = quality_from_tango(p.quality)
def __getattr__(self, name):
"""
If the member `name` is not defined in this class, try to get it
from the TangoAttribute (configuration) or from the PyTango value
"""
# Do not try to delegate special methods
if name.startswith("__") and name.endswith("__"):
raise AttributeError(
"'%s' object has no attribute %s"
% (self.__class__.__name__, name)
)
try:
# maybe name is defined in the TangoAttribute?
try:
# Use the attr reference if the attr is still valid
ret = getattr(self._attrRef, name)
except ReferenceError:
# re-create the attribute in case it was no longer referenced
# (this may happen in some rare cases in which the value is
# still used but the attr is no longer referenced elsewhere)
a = TangoAttribute.factory().getAttribute(self.__attrName)
ret = getattr(a, name)
except AttributeError:
try:
# maybe name is defined in the PyTango value?
ret = getattr(self._pytango_dev_attr, name)
except AttributeError:
raise AttributeError(
"'%s' object has no attribute %s"
% (self.__class__.__name__, name)
)
# return the attr but only after warning
from taurus.core.util.log import deprecated
deprecated(
dep="TangoAttrValue.%s" % name,
alt="TangoAttribute.%s" % name,
rel="4.0",
)
return ret
# --------------------------------------------------------
# This is for backwards compat with the API of taurus < 4
#
@taurus4_deprecation(alt=".rvalue")
def _get_value(self):
"""for backwards compat with taurus < 4"""
try:
return self.__fix_int(self.rvalue.magnitude)
except AttributeError:
return self.rvalue
@taurus4_deprecation(alt=".rvalue")
def _set_value(self, value):
"""for backwards compat with taurus < 4"""
debug("Setting %r to %s" % (value, self.name))
if self.rvalue is None: # we do not have a previous rvalue
import numpy
dtype = numpy.array(value).dtype
if numpy.issubdtype(dtype, int) or numpy.issubdtype(dtype, float):
msg = "Refusing to set ambiguous value (deprecated .value API)"
raise ValueError(msg)
else:
self.rvalue = value
elif hasattr(self.rvalue, "units"): # we do have it and is a Quantity
self.rvalue = Quantity(value, units=self.rvalue.units)
else: # we do have a previous value and is not a quantity
self.rvalue = value
value = property(_get_value, _set_value)
@taurus4_deprecation(alt=".wvalue")
def _get_w_value(self):
"""for backwards compat with taurus < 4"""
debug(repr(self))
try:
return self.__fix_int(self.wvalue.magnitude)
except AttributeError:
return self.wvalue
@taurus4_deprecation(alt=".wvalue")
def _set_w_value(self, value):
"""for backwards compat with taurus < 4"""
debug("Setting %r to %s" % (value, self.name))
if self.wvalue is None: # we do not have a previous wvalue
import numpy
dtype = numpy.array(value).dtype
if numpy.issubdtype(dtype, int) or numpy.issubdtype(dtype, float):
msg = "Refusing to set ambiguous value (deprecated .value API)"
raise ValueError(msg)
else:
self.wvalue = value
elif hasattr(self.wvalue, "units"): # we do have it and is a Quantity
self.wvalue = Quantity(value, units=self.wvalue.units)
else: # we do have a previous value and is not a quantity
self.wvalue = value
w_value = property(_get_w_value, _set_w_value)
@property
@taurus4_deprecation(alt=".error")
def has_failed(self):
"""for backwards compat with taurus < 4"""
return self.error
def __fix_int(self, value):
"""cast value to int if it is an integer.
Works on scalar and non-scalar values
"""
if self.__attrType != DataType.Integer:
return value
try:
return int(value)
except TypeError:
import numpy
return numpy.array(value, dtype="int")
[docs]class TangoAttribute(TaurusAttribute):
no_cfg_value = "-----"
no_unit = "No unit"
no_standard_unit = "No standard unit"
no_display_unit = "No display unit"
no_description = "No description"
not_specified = "Not specified"
no_min_value = no_max_value = not_specified
no_min_alarm = no_max_alarm = not_specified
no_min_warning = no_max_warning = not_specified
no_delta_t = no_delta_val = not_specified
no_rel_change = no_abs_change = not_specified
no_archive_rel_change = no_archive_abs_change = not_specified
no_archive_period = not_specified
# helper class property that stores a reference to the corresponding
# factory
_factory = None
_scheme = "tango"
_description = "A Tango Attribute"
def __init__(self, name="", parent=None, **kwargs):
# the last attribute value
self.__attr_value = None
# the last attribute error and its timestamp
self.__attr_err = None
self.__attr_err_timestamp = None
# Lock for protecting the critical read region
# where __attr_value and __attr_err are updated
self.__read_lock = threading.RLock()
# the change event identifier
self.__chg_evt_id = None
# current event subscription state
self.__subscription_state = SubscriptionState.Unsubscribed
self.__subscription_event = threading.Event()
# the parent's HW object (the PyTango Device obj)
self.__dev_hw_obj = None
# unit for which a decode warning has already been issued
self.__already_warned_unit = None
self.call__init__(TaurusAttribute, name, parent, **kwargs)
self.__deactivate_polling = False
attr_info = None
if parent:
attr_name = self.getSimpleName()
try:
attr_info = parent.attribute_query(attr_name)
except (AttributeError, PyTango.DevFailed):
# if PyTango could not connect to the dev
attr_info = None
# Set default values in case the attrinfoex is None
self.writable = False
dis_level = PyTango.DispLevel.OPERATOR
self.display_level = display_level_from_tango(dis_level)
self.tango_writable = PyTango.AttrWriteType.READ
self._units = self._unit_from_tango(PyTango.constants.UnitNotSpec)
# decode the Tango configuration attribute (adds extra members)
self._pytango_attrinfoex = None
self._decodeAttrInfoEx(attr_info)
# subscribe to configuration events (unsubscription done at cleanup)
auto_subscribe_conf = getattr(
tauruscustomsettings, "TANGO_AUTOSUBSCRIBE_CONF", True
)
self.__cfg_evt_id = None
if auto_subscribe_conf and self.factory().is_tango_subscribe_enabled():
self._subscribeConfEvents()
def __del__(self):
self.cleanUp()
[docs] def cleanUp(self):
self.trace("[TangoAttribute] cleanUp")
self._unsubscribeConfEvents()
self._unsubscribeChangeEvents()
TaurusAttribute.cleanUp(self)
self.__dev_hw_obj = None
self._pytango_attrinfoex = None
def __getattr__(self, name):
try:
return getattr(self._pytango_attrinfoex, name)
except AttributeError:
raise AttributeError(
"'TangoAttribute' object has no attribute %s" % name
)
[docs] def getNewOperation(self, value):
attr_value = PyTango.AttributeValue()
attr_value.name = self.getSimpleName()
attr_value.value = self.encode(value)
op = WriteAttrOperation(self, attr_value)
return op
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
# PyTango connection
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
[docs] def isInteger(self, inc_array=False):
tgtype = self._tango_data_type
return PyTango.is_int_type(tgtype, inc_array=inc_array)
[docs] def isFloat(self, inc_array=False):
tgtype = self._tango_data_type
return PyTango.is_float_type(tgtype, inc_array=inc_array)
[docs] def isBoolean(self, inc_array=False):
tgtype = self._tango_data_type
# PyTango.is_bool_type is not implemented in Tango7 and neither in
# some Tango8, at least 8.1.1. Avoid to use is_bool_type method
# while taurus is still compatible with these versions.
# PyTango.is_bool_type(tgtype, inc_array=inc_array)
if tgtype == PyTango.CmdArgType.DevBoolean:
return True
if inc_array and tgtype == PyTango.CmdArgType.DevVarBooleanArray:
return True
return False
[docs] def isState(self):
"""
returns whether the attribute of tango DevState type
"""
tgtype = self._tango_data_type
return tgtype == PyTango.CmdArgType.DevState
[docs] def encode(self, value):
"""Translates the given value into a tango compatible value according
to the attribute data type.
Raises `pint.DimensionalityError` if value is a Quantity and it
cannot be expressed in the units of the attribute set in the DB
"""
if isinstance(value, Quantity):
# convert to units of the attr in the DB (or raise an exception)
magnitude = value.to(self._units).magnitude
else:
magnitude = value
fmt = self.getDataFormat()
tgtype = self._tango_data_type
if fmt == DataFormat._0D:
if tgtype == PyTango.CmdArgType.DevDouble:
attrvalue = float(magnitude)
elif tgtype == PyTango.CmdArgType.DevFloat:
# We encode to float, but rounding to Tango::DevFloat precision
# see: http://sf.net/p/sardana/tickets/162
attrvalue = float(numpy.float32(magnitude))
elif PyTango.is_int_type(tgtype):
# changed as a partial workaround to a problem in PyTango
# writing to DevULong64 attributes (see ALBA RT#29793)
attrvalue = int(magnitude)
elif tgtype == PyTango.CmdArgType.DevBoolean:
try:
attrvalue = bool(int(magnitude))
except Exception:
attrvalue = str(magnitude).lower() == "true"
elif tgtype == PyTango.CmdArgType.DevUChar:
attrvalue = int(magnitude)
elif tgtype in (
PyTango.CmdArgType.DevState,
PyTango.CmdArgType.DevEncoded,
):
attrvalue = magnitude
else:
attrvalue = str(magnitude)
elif fmt in (DataFormat._1D, DataFormat._2D):
if PyTango.is_int_type(tgtype):
# cast to integer because the magnitude conversion gives floats
attrvalue = numpy.array(magnitude, copy=False, dtype="int64")
elif tgtype == PyTango.CmdArgType.DevUChar:
attrvalue = magnitude.view("uint8")
else:
attrvalue = magnitude
else:
attrvalue = str(magnitude)
return attrvalue
[docs] def decode(self, attr_value):
"""Decodes a value that was received from PyTango into the expected
representation
"""
if self._pytango_attrinfoex is None:
self.getAttributeInfoEx(cache=False)
self._decodeAttrInfoEx()
value = TangoAttrValue(pytango_dev_attr=attr_value, attr=self)
return value
[docs] def write(self, value, with_read=True):
"""Write the value in the Tango Device Attribute"""
try:
dev = self.getParentObj()
name, value = self.getSimpleName(), self.encode(value)
if self.isUsingEvents() or not self.isReadWrite():
with_read = False
if with_read:
try:
result = dev.write_read_attribute(name, value)
except AttributeError:
# handle old PyTango
dev.write_attribute(name, value)
result = dev.read_attribute(name)
except PyTango.DevFailed as df:
for err in df.args:
# Handle old device servers
if err.reason == "API_UnsupportedFeature":
dev.write_attribute(name, value)
result = dev.read_attribute(name)
break
else:
raise df
self.poll(single=False, value=result, time=time.time())
return self.decode(result)
else:
dev.write_attribute(name, value)
return None
except PyTango.DevFailed as df:
err = df.args[0]
self.error(
"[Tango] write failed (%s): %s" % (err.reason, err.desc)
)
raise df
except Exception as e:
self.error("[Tango] write failed: %s" % str(e))
raise e
[docs] def poll(self, single=True, value=None, time=None, error=None):
"""Notify listeners when the attribute has been polled"""
with self.__read_lock:
try:
if single:
self.read(cache=False)
else:
value = self.decode(value)
self.__attr_err = error
if self.__attr_err:
self.__attr_err_timestamp = time
raise self.__attr_err
# Avoid "valid-but-outdated" notifications
# if FILTER_OLD_TANGO_EVENTS is enabled
# and the given timestamp is older than the timestamp
# of the cached value
filter_old_event = getattr(
tauruscustomsettings, "FILTER_OLD_TANGO_EVENTS", False
)
if (
self.__attr_value is not None
and filter_old_event
and time is not None
and time < self.__attr_value.time.totime()
):
return
self.__attr_value = value
except PyTango.DevFailed as df:
self.__subscription_event.set()
self.debug("Error polling: %s" % df.args[0].desc)
self.traceback()
self.fireEvent(TaurusEventType.Error, self.__attr_err)
except Exception as e:
self.__subscription_event.set()
self.debug("Error polling: %s" % str(e))
self.fireEvent(TaurusEventType.Error, self.__attr_err)
else:
self.__subscription_event.set()
self.fireEvent(TaurusEventType.Periodic, self.__attr_value)
[docs] def read(self, cache=True):
"""Returns the current value of the attribute.
If `cache` is not False, or expired, or the attribute has events
active, then it will return the local cached value. Otherwise it will
read the attribute value from the tango device.
The cached value expires if it is older than the value (im ms) passed
as the `cache` argument or the *polling period* if `cache==True`
(default). If the cache is expired a reading will be done just as if
cache was False.
:param cache: use cache value or make readout, eventually pass a
cache's expiration period in milliseconds
:type cache: :obj:`bool` or :obj:`float`
:return: attribute value
:rtype: :obj:`~taurus.core.tango.TangoAttributeValue`
"""
curr_time = time.time()
if cache:
try:
attr_timestamp = self.__attr_value.time.totime()
except AttributeError:
if self.__attr_err_timestamp is not None:
attr_timestamp = self.__attr_err_timestamp
else:
attr_timestamp = 0
dt = (curr_time - attr_timestamp) * 1000
if cache is True: # cache *is* a bool True
expiration_period = self.getPollingPeriod()
else: # cache is a non-zero numeric value
expiration_period = cache
if dt < expiration_period:
if self.__attr_value is not None:
return self.__attr_value
elif self.__attr_err is not None:
self.debug(
"[Tango] read from cache failed (%s): %s",
self.fullname,
self.__attr_err,
)
raise self.__attr_err
if not cache or (
self.__subscription_state
in (
SubscriptionState.PendingSubscribe,
SubscriptionState.Unsubscribed,
)
and not self.isPollingActive()
):
with self.__read_lock:
try:
dev = self.getParentObj()
v = dev.read_attribute(self.getSimpleName())
self.__attr_value = self.decode(v)
self.__attr_err = None
self.__attr_err_timestamp = None
return self.__attr_value
except PyTango.DevFailed as df:
self.__attr_value = None
self.__attr_err = df
self.__attr_err_timestamp = curr_time
err = df.args[0]
self.debug(
"[Tango] read failed (%s): %s", err.reason, err.desc
)
raise df
except Exception as e:
self.__attr_value = None
self.__attr_err = e
self.__attr_err_timestamp = curr_time
self.debug("[Tango] read failed: %s", e)
raise e
elif self.__subscription_state in (
SubscriptionState.Subscribing,
SubscriptionState.PendingSubscribe,
):
self.__subscription_event.wait()
if self.__attr_err is not None:
raise self.__attr_err
return self.__attr_value
[docs] def getAttributeProxy(self):
"""Convenience method that creates and returns a PyTango.AttributeProxy
object
"""
return PyTango.AttributeProxy(self.getFullName())
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
# API for listeners
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
def __fireRegisterEvent(self, listener):
"""fire the first config and change (or error) events"""
try:
v = self.read()
# note: it may seem redundant, but some widgets may only react to
# one or another type, so we should send both for bck-compat
# Taurus4 widgets should never use config events since the same
# info is always emitted in a change event
self.fireEvent(TaurusEventType.Config, v, listener)
self.fireEvent(TaurusEventType.Change, v, listener)
except Exception:
self.fireEvent(TaurusEventType.Error, self.__attr_err, listener)
[docs] def addListener(self, listener):
"""Add a TaurusListener object in the listeners list.
If it is the first element and Polling is enabled starts the
polling mechanism.
If the listener is already registered nothing happens.
"""
listeners = self._listeners
initial_subscription_state = self.__subscription_state
ret = TaurusAttribute.addListener(self, listener)
if not ret:
return ret
assert len(listeners) >= 1
if (
self.__subscription_state == SubscriptionState.Unsubscribed
and len(listeners) == 1
):
self._subscribeChangeEvents()
# if initial_subscription_state == SubscriptionState.Subscribed:
if len(listeners) > 1 and (
initial_subscription_state == SubscriptionState.Subscribed
or self.isPollingActive()
):
sm = self._serialization_mode
if sm == TaurusSerializationMode.TangoSerial:
self.__fireRegisterEvent((listener,))
else:
job = _BoundMethodWeakrefWithCall(self.__fireRegisterEvent)
Manager().enqueueJob(
job, job_args=((listener,),), serialization_mode=sm
)
return ret
[docs] def removeListener(self, listener):
"""Remove a TaurusListener from the listeners list. If polling enabled
and it is the last element the stop the polling timer.
If the listener is not registered nothing happens.
"""
ret = TaurusAttribute.removeListener(self, listener)
if not ret:
return ret
if self.hasListeners():
return ret
if self.__subscription_state != SubscriptionState.Unsubscribed:
self._unsubscribeChangeEvents()
return ret
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
# API for attribute configuration
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
[docs] def setConfigEx(self, config):
self.getParentObj().set_attribute_config([config])
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
# PyTango event handling (private)
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
[docs] def isUsingEvents(self):
return self.__subscription_state == SubscriptionState.Subscribed
[docs] def getSubscriptionState(self):
return self.__subscription_state
def _process_event_exception(self, ex):
pass
def _subscribeChangeEvents(self):
"""Enable subscription to the attribute events. If change events are
not supported polling is activated
"""
if self.__chg_evt_id is not None:
self.warning(
"chg events already subscribed (id=%s)" % self.__chg_evt_id
)
return
if self.__dev_hw_obj is None:
dev = self.getParentObj()
if dev is None:
self.debug("failed to subscribe to chg events: device is None")
return
self.__dev_hw_obj = dev.getDeviceProxy()
if self.__dev_hw_obj is None:
self.debug("failed to subscribe to chg events: HW is None")
return
if not self.factory().is_tango_subscribe_enabled():
self.enablePolling(True)
return
try:
self.__subscription_state = SubscriptionState.Subscribing
self._call_dev_hw_subscribe_event(False)
except Exception:
self.__subscription_state = SubscriptionState.PendingSubscribe
self._activatePolling()
self._call_dev_hw_subscribe_event(True)
def _call_dev_hw_subscribe_event(self, stateless=True):
"""Executes event subscription on parent TangoDevice objectName"""
if self.__chg_evt_id is not None:
self.warning(
"chg events already subscribed (id=%s)", self.__chg_evt_id
)
return
attr_name = self.getSimpleName()
# connects to self.push_event callback
# TODO: _BoundMethodWeakrefWithCall is used as workaround for
# PyTango #185 issue
self.__chg_evt_id = self.__dev_hw_obj.subscribe_event(
attr_name,
PyTango.EventType.CHANGE_EVENT,
_BoundMethodWeakrefWithCall(self.push_event),
[],
stateless,
)
return self.__chg_evt_id
def _unsubscribeChangeEvents(self):
# Careful in this method: This is intended to be executed in the
# cleanUp so we should not access external objects from the factory,
# like the parent object
if self.__dev_hw_obj is not None and self.__chg_evt_id is not None:
self.trace(
"Unsubscribing to change events (ID=%d)", self.__chg_evt_id
)
try:
self.__dev_hw_obj.unsubscribe_event(self.__chg_evt_id)
self.__chg_evt_id = None
except PyTango.DevFailed as df:
if len(df.args) and df.args[0].reason == "API_EventNotFound":
# probably tango shutdown has been initiated before and
# it unsubscribed from events itself
pass
else:
self.debug("Failed: %s", df.args[0].desc)
self.trace(str(df))
self._deactivatePolling()
self.__subscription_state = SubscriptionState.Unsubscribed
def _subscribeConfEvents(self):
"""Enable subscription to the attribute configuration events."""
self.trace("Subscribing to configuration events...")
if self.__cfg_evt_id is not None:
self.warning(
"cfg events already subscribed (id=%s)" % self.__cfg_evt_id
)
return
if self.__dev_hw_obj is None:
dev = self.getParentObj()
if dev is None:
self.debug("failed to subscribe to cfg events: device is None")
return
self.__dev_hw_obj = dev.getDeviceProxy()
if self.__dev_hw_obj is None:
self.debug("failed to subscribe to cfg events: HW is None")
return
attr_name = self.getSimpleName()
try:
# connects to self.push_event callback
# TODO: _BoundMethodWeakrefWithCall is used as workaround for
# PyTango #185 issue
self.__cfg_evt_id = self.__dev_hw_obj.subscribe_event(
attr_name,
PyTango.EventType.ATTR_CONF_EVENT,
_BoundMethodWeakrefWithCall(self.push_event),
[],
True,
)
except PyTango.DevFailed:
self.debug("Error trying to subscribe to CONFIGURATION events.")
self.traceback()
# Subscription failed either because event mechanism is not
# available or because the device server is not running.
# The first possibility is assumed so an attempt to get the
# configuration manually is done
# TODO decide what should be done here
try:
attrinfoex = self.__dev_hw_obj.attribute_query(attr_name)
self._decodeAttrInfoEx(attrinfoex)
except Exception:
self.debug("Error getting attribute configuration")
self.traceback()
def _unsubscribeConfEvents(self):
# Careful in this method: This is intended to be executed in the
# cleanUp so we should not access external objects from the factory,
# like the parent object
if self.__cfg_evt_id is not None and self.__dev_hw_obj is not None:
self.trace(
"Unsubscribing to configuration events (ID=%s)",
str(self.__cfg_evt_id),
)
try:
self.__dev_hw_obj.unsubscribe_event(self.__cfg_evt_id)
self.__cfg_evt_id = None
except PyTango.DevFailed as e:
self.debug("Error trying to unsubscribe configuration events")
self.trace(str(e))
[docs] def subscribePendingEvents(self):
"""Execute delayed event subscription"""
if (
self.__subscription_state == SubscriptionState.Unsubscribed
or self.isPollingActive()
):
self.__subscription_state = SubscriptionState.PendingSubscribe
self._subscribeConfEvents()
self._call_dev_hw_subscribe_event(True)
[docs] def push_event(self, event):
"""Method invoked by the PyTango layer when an event occurs.
It propagates the event to listeners and delegates other tasks to
specific handlers for different event types.
"""
with self.__read_lock:
# if it is a configuration event
if isinstance(event, PyTango.AttrConfEventData):
etype, evalue = self._pushConfEvent(event)
# if it is an attribute event
else:
etype, evalue = self._pushAttrEvent(event)
# notify the listeners if required (i.e, if etype is not None)
if etype is None:
return
manager = Manager()
listeners = tuple(self._listeners)
sm = self._serialization_mode
if sm == TaurusSerializationMode.TangoSerial:
self.fireEvent(etype, evalue, listeners=listeners)
else:
job = _BoundMethodWeakrefWithCall(self.fireEvent)
manager.enqueueJob(
job,
job_args=(etype, evalue),
job_kwargs={"listeners": listeners},
serialization_mode=sm,
)
# Deactivate polling in case of PyTango.DevFailed
# it must be managed out of the critical region to avoid deadlock
if self.__deactivate_polling:
self.__deactivate_polling = False
self._deactivatePolling()
def _pushAttrEvent(self, event):
"""Handler of (non-configuration) events from the PyTango layer.
It handles the subscription and the (de)activation of polling
:param event:
:type event: A PyTango event
:return: Tuple containing the event type and the event value. evt_type
is a `TaurusEventType` (or None to indicate that there should not
be notification to listeners). evt_value is a TaurusValue, an
Exception, or None.
:rtype: evt_type, evt_value
"""
if not event.err:
attr_value = self.decode(event.attr_value)
filter_old_event = getattr(
tauruscustomsettings, "FILTER_OLD_TANGO_EVENTS", False
)
time = event.attr_value.time.totime()
# Discard "valid" events if the attribute value is not None
# and FILTER_OLD_TANGO_EVENTS is enabled
# and the given timestamp is older than the timestamp
# of the cache value
if (
self.__attr_value is not None
and self.__subscription_state == SubscriptionState.Subscribed
and filter_old_event
and time < self.__attr_value.time.totime()
):
return [None, None]
self.__attr_value = attr_value
self.__attr_err = None
self.__attr_err_timestamp = None
self.__subscription_state = SubscriptionState.Subscribed
self.__subscription_event.set()
if not self.isPollingForced():
self.disablePolling()
return TaurusEventType.Change, self.__attr_value
elif event.errors[0].reason in EVENT_TO_POLLING_EXCEPTIONS:
if not self.isPollingActive():
self.info(
"Activating polling. Reason: %s", event.errors[0].reason
)
self.__subscription_state = SubscriptionState.PendingSubscribe
self._activatePolling()
return [None, None]
else:
self.__attr_value = None
self.__attr_err = PyTango.DevFailed(*event.errors)
self.__attr_err_timestamp = event.reception_date.totime()
self.__subscription_state = SubscriptionState.Subscribed
self.__subscription_event.set()
self.__deactivate_polling = True
return TaurusEventType.Error, self.__attr_err
def _pushConfEvent(self, event):
"""Handler of AttrConfEventData events from the PyTango layer.
:param event:
:type event: PyTango.AttrConfEventData
:return: Tuple containing the event type and the event value. evt_type
is a `TaurusEventType` (or None to indicate that there should not
be notification to listeners). evt_value is a TaurusValue, an
Exception, or None.
:rtype: evt_type, evt_value
"""
if not event.err:
# update conf-related attributes
self._decodeAttrInfoEx(event.attr_conf)
# make sure that there is a self.__attr_value
if self.__attr_value is None:
# TODO: maybe we can avoid this read?
self.__attr_value = self.getValueObj(cache=False)
return TaurusEventType.Config, self.__attr_value
else:
self.__attr_value = None
self.__attr_err = PyTango.DevFailed(*event.errors)
self.__attr_err_timestamp = event.reception_date.totime()
return TaurusEventType.Error, self.__attr_err
[docs] def isWrite(self, cache=True):
return self.getTangoWritable(cache) == PyTango.AttrWriteType.WRITE
[docs] def isReadOnly(self, cache=True):
return not self.getTangoWritable(cache) == PyTango.AttrWriteType.READ
[docs] def isReadWrite(self, cache=True):
return self.getTangoWritable(cache) == PyTango.AttrWriteType.READ_WRITE
[docs] def getTangoWritable(self, cache=True):
"""like TaurusAttribute.isWritable(), but it returns a
PyTango.AttrWriteType instead of a bool
"""
return self.tango_writable
[docs] def getLabel(self, cache=True):
return self._label
[docs] def getRange(self, cache=True):
return self._range
[docs] def getLimits(self, cache=True):
return self.getRange(cache)
[docs] def getRanges(self, cache=True):
return self.getRange()
[docs] def getAlarms(self, cache=True):
return self._alarm
[docs] def getWarnings(self, cache=True):
return self._warning
[docs] def getMaxDim(self, cache=True):
return self.max_dim_x, self.max_dim_y
[docs] def setLimits(self, low, high):
self.setRange([low, high])
[docs] def setLabel(self, lbl):
TaurusAttribute.setLabel(self, lbl)
infoex = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
infoex.label = lbl
self._applyConfig()
[docs] def setRange(self, *limits):
if isinstance(limits[0], list):
limits = limits[0]
low, high = limits
low = Quantity(low)
if low.unitless:
low = Quantity(low.magnitude, self._units)
high = Quantity(high)
if high.unitless:
high = Quantity(high.magnitude, self._units)
TaurusAttribute.setRange(self, [low, high])
infoex = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
if low.magnitude != float("-inf"):
infoex.min_value = str(low.to(self._units).magnitude)
else:
infoex.min_value = "Not specified"
if high.magnitude != float("inf"):
infoex.max_value = str(high.to(self._units).magnitude)
else:
infoex.max_value = "Not specified"
self._applyConfig()
[docs] def setWarnings(self, *limits):
if isinstance(limits[0], list):
limits = limits[0]
low, high = limits
low = Quantity(low)
if low.unitless:
low = Quantity(low.magnitude, self._units)
high = Quantity(high)
if high.unitless:
high = Quantity(high.magnitude, self._units)
TaurusAttribute.setWarnings(self, [low, high])
infoex = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
if low.magnitude != float("-inf"):
infoex.alarms.min_warning = str(low.to(self._units).magnitude)
else:
infoex.alarms.min_warning = "Not specified"
if high.magnitude != float("inf"):
infoex.alarms.max_warning = str(high.to(self._units).magnitude)
else:
infoex.alarms.max_warning = "Not specified"
self._applyConfig()
[docs] def setAlarms(self, *limits):
if isinstance(limits[0], list):
limits = limits[0]
low, high = limits
low = Quantity(low)
if low.unitless:
low = Quantity(low.magnitude, self._units)
high = Quantity(high)
if high.unitless:
high = Quantity(high.magnitude, self._units)
TaurusAttribute.setAlarms(self, [low, high])
infoex = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
if low.magnitude != float("-inf"):
infoex.alarms.min_alarm = str(low.to(self._units).magnitude)
else:
infoex.alarms.min_alarm = "Not specified"
if high.magnitude != float("inf"):
infoex.alarms.max_alarm = str(high.to(self._units).magnitude)
else:
infoex.alarms.max_alarm = "Not specified"
self._applyConfig()
def _applyConfig(self):
config = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
self.setConfigEx(config)
def _decodeAttrInfoEx(self, pytango_attrinfoex=None):
if pytango_attrinfoex is None:
return
self._pytango_attrinfoex = i = pytango_attrinfoex
self.writable = i.writable != PyTango.AttrWriteType.READ
self._label = i.label
self.data_format = data_format_from_tango(i.data_format)
desc = description_from_tango(i.description)
if desc != "":
self._description = desc
self.type = data_type_from_tango(i.data_type)
###############################################################
# changed in taurus4: range, alarm and warning now return
# quantities if appropriate
if self.isNumeric():
units = self._unit_from_tango(i.unit)
else:
units = UR.parse_units("")
if PyTango.is_numerical_type(i.data_type, inc_array=True):
Q_ = partial(
quantity_from_tango_str, units=units, dtype=i.data_type
)
ninf, inf = float("-inf"), float("inf")
min_value = Q_(i.min_value)
if min_value is None:
min_value = Quantity(ninf, units)
max_value = Q_(i.max_value)
if max_value is None:
max_value = Quantity(inf, units)
min_alarm = Q_(i.alarms.min_alarm)
if min_alarm is None:
min_alarm = Quantity(ninf, units)
max_alarm = Q_(i.alarms.max_alarm)
if max_alarm is None:
max_alarm = Quantity(inf, units)
min_warning = Q_(i.alarms.min_warning)
if min_warning is None:
min_warning = Quantity(ninf, units)
max_warning = Q_(i.alarms.max_warning)
if max_warning is None:
max_warning = Quantity(inf, units)
self._range = [min_value, max_value]
self._warning = [min_warning, max_warning]
self._alarm = [min_alarm, max_alarm]
###############################################################
# The following members will be accessed via __getattr__
# self.standard_unit
# self.display_unit
# self.disp_level
###############################################################
# Tango-specific extension of TaurusConfigValue
self.display_level = display_level_from_tango(i.disp_level)
self.tango_writable = i.writable
self.max_dim = i.max_dim_x, i.max_dim_y
###############################################################
fmt = standard_display_format_from_tango(i.data_type, i.format)
self.format_spec = fmt.lstrip("%") # format specifier
match = re.search(r"[^\.]*\.(?P<precision>[0-9]+)[eEfFgG%]", fmt)
if match:
self.precision = int(match.group(1))
elif re.match(r"%[0-9]*d", fmt):
self.precision = 0
# self._units and self._display_format is to be used by
# TangoAttrValue for performance reasons. Do not rely on it in other
# code
self._units = units
@property
@deprecation_decorator(alt="format_spec or precision", rel="4.0.4")
def format(self):
"""for backwards compat with taurus < 4"""
i = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
return standard_display_format_from_tango(i.data_type, i.format)
@property
def _tango_data_type(self):
"""returns the *tango* (not Taurus) data type"""
i = self._pytango_attrinfoex or PyTango.AttributeInfoEx()
return i.data_type
def _unit_from_tango(self, unit):
# silently treat unit-not-defined as unitless
# TODO: consider logging that unit-not-defined is treated as unitless
# TODO: See https://gitlab.com/taurus-org/taurus/-/issues/584 and
# https://gitlab.com/taurus-org/taurus/-/merge_requests/662
# The extra comparison to "No unit" is necessary where
# server/database runs Tango 7 or 8 and client runs higher versions.
if (
unit == PyTango.constants.UnitNotSpec
or unit == "No unit"
or unit is None
):
unit = ""
try:
return UR.parse_units(unit)
except Exception as e:
# TODO: Maybe we could dynamically register the unit in the UR
msg = 'Unknown unit "%s" (will be treated as unitless)'
if self.__already_warned_unit == unit:
self.debug(msg, unit)
else:
self.warning(msg, unit)
self.debug("%r", e)
self.__already_warned_unit = unit
return UR.parse_units("")
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
# Deprecated methods
# -~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
@taurus4_deprecation(alt=".description")
def getDescription(self, cache=True):
return self.description
@taurus4_deprecation(alt=".description")
def setDescription(self, descr):
self.description = descr
@taurus4_deprecation()
def isInformDeviceOfErrors(self):
return False
@taurus4_deprecation(dbg_msg="Deprecated method")
def displayValue(self, value):
return str(value)
@taurus4_deprecation(alt="getLabel")
def getDisplayValue(self, cache=True):
attrvalue = self.getValueObj(cache=cache)
if not attrvalue:
return None
v = attrvalue.rvalue
return self.displayValue(v)
@taurus4_deprecation(alt=".rvalue.units")
def getStandardUnit(self, cache=True):
try:
return str(self.getValueObj(cache).rvalue.units)
except Exception:
return None
@taurus4_deprecation(alt=".rvalue.units")
def getDisplayUnit(self, cache=True):
try:
return str(self.getValueObj(cache).rvalue.units)
except Exception:
return None
@taurus4_deprecation(dbg_msg="Do not use")
def getDisplayWriteValue(self, cache=True):
raise NotImplementedError("Not available since Taurus4")
@taurus4_deprecation(alt="isWritable")
def getWritable(self, cache=True):
return self.isWritable(cache)
@taurus4_deprecation(alt="self.data_format")
def isScalar(self, cache=True):
# cache is ignored, it is only for back. compat.
return self.data_format == DataFormat._0D
@taurus4_deprecation(alt="self.data_format")
def isSpectrum(self, cache=True):
# cache is ignored, it is only for back. compat.
return self.data_format == DataFormat._1D
@taurus4_deprecation(alt="self.data_format")
def isImage(self):
return self.data_format == DataFormat._2D
@taurus4_deprecation(alt="getMaxDim")
def getMaxDimX(self, cache=True):
dim = self.getMaxDim(cache)
if dim:
return dim[0]
else:
return None
@taurus4_deprecation(alt="getMaxDim")
def getMaxDimY(self, cache=True):
dim = self.getMaxDim(cache)
if dim:
return dim[1]
else:
return None
@taurus4_deprecation(dbg_msg="Deprecated method")
def getShape(self, cache=True):
if self.isScalar(cache):
return ()
elif self.isSpectrum():
return (self.getMaxDimX(),)
else:
return self.getMaxDim()
@taurus4_deprecation(alt="getAttributeInfoEx")
def getParam(self, param_name):
"""Get attributes of AttributeInfoEx (PyTango)"""
try:
return getattr(self._pytango_attrinfoex, param_name)
except Exception:
return None
@taurus4_deprecation(alt="PyTango")
def setParam(self, param_name, value):
"""Set attributes of AttributeInfoEx (PyTango)"""
if hasattr(self._pytango_attrinfoex, param_name):
setattr(self._pytango_attrinfoex, param_name, str(value))
self._applyConfig()
@taurus4_deprecation(alt="self")
def getConfig(self):
"""Returns the current configuration of the attribute."""
return weakref.proxy(self)
[docs] def getAttributeInfoEx(self, cache=True):
if not cache:
try:
attr_name = self.getSimpleName()
attrinfoex = self.__dev_hw_obj.attribute_query(attr_name)
self._decodeAttrInfoEx(attrinfoex)
except Exception as e:
self.debug("Error getting attribute configuration: %s", e)
self.traceback()
return self._pytango_attrinfoex
@taurus4_deprecation(alt=".rvalue.units")
def getUnit(self, cache=True):
"""for backwards compat with taurus < 4"""
try:
return str(self.getValueObj(cache).rvalue.units)
except Exception:
return None
@taurus4_deprecation(alt=".rvalue.units")
def _set_unit(self, value):
"""for backwards compat with taurus < 4"""
extra_msg = "Ignoring setting of units of %s to %r" % (
self.name,
value,
)
self.debug(extra_msg)
@taurus4_deprecation(alt="getMinRange")
def getMinValue(self, cache=True):
return self.getMinRange()
@taurus4_deprecation(alt="getMaxRange")
def getMaxValue(self, cache=True):
return self.getMaxRange()
@taurus4_deprecation(alt="getRange")
def getCLimits(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is not None:
value = [
self._pytango_attrinfoex.min_value,
self._pytango_attrinfoex.max_value,
]
else:
value = [self.not_specified, self.not_specified]
return value
@taurus4_deprecation(alt="getAlarms")
def getCAlarms(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is not None:
value = [
self._pytango_attrinfoex.min_alarm,
self._pytango_attrinfoex.max_alarm,
]
else:
value = [self.not_specified, self.not_specified]
return value
@taurus4_deprecation(alt="getWarnings")
def getCWarnings(self):
if self._pytango_attrinfoex is not None:
value = [
self._pytango_attrinfoex.alarms.min_warning,
self._pytango_attrinfoex.alarms.max_warning,
]
else:
value = [self.not_specified, self.not_specified]
return value
@taurus4_deprecation(alt="getRange + getAlarms + getWarnings")
def getCRanges(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is not None:
value = [
self._pytango_attrinfoex.min_value,
self._pytango_attrinfoex.min_alarm,
self._pytango_attrinfoex.alarms.min_warning,
self._pytango_attrinfoex.alarms.max_warning,
self._pytango_attrinfoex.max_alarm,
self._pytango_attrinfoex.max_value,
]
else:
value = [
self.not_specified,
self.not_specified,
self.not_specified,
self.not_specified,
self.not_specified,
self.not_specified,
]
return value
@taurus4_deprecation(alt=".alarms[0]")
def getMinAlarm(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is None:
return None
return self._pytango_attrinfoex.alarms.min_alarm
@taurus4_deprecation(alt=".alarms[1]")
def getMaxAlarm(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is None:
return None
return self._pytango_attrinfoex.alarms.max_alarm
@taurus4_deprecation(alt=".warnings[0]")
def getMinWarning(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is None:
return None
return self._pytango_attrinfoex.alarms.min_warning
@taurus4_deprecation(alt=".warnings[1]")
def getMaxWarning(self):
"""for backwards compat with taurus < 4"""
if self._pytango_attrinfoex is None:
return None
return self._pytango_attrinfoex.alarms.max_warning
@taurus4_deprecation(alt=".alarms")
def setMinAlarm(self, value):
if self._pytango_attrinfoex is None:
self._pytango_attrinfoex.alarms.min_alarm = str(value)
self._applyConfig()
@taurus4_deprecation(alt=".alarms")
def setMaxAlarm(self, value):
if self._pytango_attrinfoex is None:
self._pytango_attrinfoex.alarms.max_alarm = str(value)
self._applyConfig()
@taurus4_deprecation(alt=".warnings")
def setMinWarning(self, value):
if self._pytango_attrinfoex is None:
self._pytango_attrinfoex.alarms.min_warning = str(value)
self._applyConfig()
@taurus4_deprecation(alt=".warnings")
def setMaxWarning(self, value):
if self._pytango_attrinfoex is None:
self._pytango_attrinfoex.alarms.max_warning = str(value)
self._applyConfig()
# deprecated property!
unit = property(getUnit, _set_unit)
climits = property(getCLimits)
calarms = property(getCAlarms)
cwarnings = property(getCAlarms)
cranges = property(getCRanges)
min_alarm = property(getMinAlarm, setMinAlarm)
max_alarm = property(getMaxAlarm, setMaxAlarm)
min_warning = property(getMinWarning, setMinWarning)
max_warning = property(getMaxWarning, setMaxWarning)
# properties
label = property(getLabel, setLabel)
range = property(getRange, setRange)
warnings = property(getWarnings, setWarnings)
alarms = property(getAlarms, setAlarms)
@property
def description(self):
return self._description
@property
def dev_alias(self):
self.deprecated(
dep="dev_alias", alt="getParentObj().name", rel="tep14"
)
parent = self.getParentObj()
if parent is None:
return None
else:
return parent.name
@description.setter
def description(self, descr):
if descr != self._description:
if descr == "":
descr = "A Tango Attribute"
self._description = descr
self._applyConfig()
[docs]class TangoAttributeEventListener(EventListener):
"""A class that listens for an event with a specific value
Note: Since this class stores for each event value the last timestamp when
it occured, it should only be used for events for which the event value
domain (possible values) is limited and well known (ex: an enum)
"""
def __init__(self, attr):
EventListener.__init__(self)
self.attr = attr
attr.addListener(self)
[docs] def eventReceived(self, s, t, v):
if t not in (TaurusEventType.Change, TaurusEventType.Periodic):
return
self.fireEvent(v.value)
def test1():
import numpy
from taurus import Attribute
a = Attribute("sys/tg_test/1/ulong64_scalar")
a.write(numpy.uint64(88))
if __name__ == "__main__":
test1()