#
# Project: MXCuBE
# https://github.com/mxcube
#
# This file is part of MXCuBE software.
#
# MXCuBE 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.
#
# MXCuBE 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 MXCuBE. If not, see <http://www.gnu.org/licenses/>.
""" AbstractNState class - interface for N state devices.
Defines BaseValueEnum, initialise_values and value_to_enum methds.
Implements validate_value, set/update limits.
"""
import abc
import ast
from enum import Enum, unique
from mxcubecore.HardwareObjects.abstract.AbstractActuator import AbstractActuator
__copyright__ = """ Copyright © 2010-2022 by the MXCuBE collaboration """
__license__ = "LGPLv3+"
[docs]@unique
class BaseValueEnum(Enum):
"""Defines only the compulsory unknown."""
UNKNOWN = "UNKNOWN"
[docs]class AbstractNState(AbstractActuator):
"""Abstract base class for N state objects."""
__metaclass__ = abc.ABCMeta
VALUES = BaseValueEnum
[docs] def init(self):
"""Initilise the predefined values"""
super().init()
self.initialise_values()
# default_value should be an Enum, if defined
if self.default_value is not None and not isinstance(self.default_value, Enum):
self.default_value = self.value_to_enum(self.default_value)
self.update_value(self.default_value)
[docs] def validate_value(self, value):
"""Check if the value is one of the predefined values.
Args:
value(Enum): value to check
Returns:
(bool): True if within the values.
"""
return value in self.VALUES
[docs] def set_limits(self, limits):
"""Set the low and high limits.
Args:
limits (tuple): two element (low limit, high limit) tuple.
Raises:
NotImplementedError
"""
raise NotImplementedError
[docs] def update_limits(self, limits=None):
"""Check if the limits have changed.
Args:
limits(tuple): two elements (low limit, high limit) tuple.
Raises:
NotImplementedError
"""
raise NotImplementedError
[docs] def initialise_values(self):
"""Initialise the ValueEnum with the values from the config."""
try:
values = ast.literal_eval(self.get_property("values"))
values_dict = dict(**{item.name: item.value for item in self.VALUES})
values_dict.update(values)
self.VALUES = Enum("ValueEnum", values_dict)
except (ValueError, TypeError):
pass
[docs] def value_to_enum(self, value, idx=0):
"""Tranform a value to Enum
Args:
value(str, int, float, tuple): value
idx(int): Index in the value, if tuple
Returns:
(Enum): Enum member, corresponding to the value or UNKNOWN.
"""
for enum_var in self.VALUES.__members__.values():
if value == enum_var.value:
return enum_var
if isinstance(enum_var.value, tuple) and value == enum_var.value[idx]:
return enum_var
return self.VALUES.UNKNOWN
[docs] def re_emit_values(self):
"""Update values for all internal attributes"""
self.update_value(self.get_value())
# NB DO NOT 'FIX', this is deliberate.
# One would normally call super(AbstractNState ...), however we
# want to call re_emit_values of HardwareObject to avoid the limit
# handling implemented in AbstractActuator
super(AbstractActuator, self).re_emit_values()