# -*- coding: utf-8 -*- # ***************************************************************************** # # This program is free software; you can redistribute it and/or modify it under # the terms of the GNU General Public License as published by the Free Software # Foundation; either version 2 of the License, or (at your option) any later # version. # # This program 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 General Public License for more # details. # # You should have received a copy of the GNU General Public License along with # this program; if not, write to the Free Software Foundation, Inc., # 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # # Module authors: # Enrico Faulhaber # Markus Zolliker # # ***************************************************************************** """Define classes for Parameters/Commands and Overriding them""" import inspect from secop.datatypes import CommandType, DataType, StringType, BoolType, EnumType, DataTypeType, ValueType, OrType, \ NoneOr, TextType, IntRange, TupleOf, StructOf from secop.errors import ProgrammingError, BadValueError from secop.properties import HasProperties, Property UNSET = object() # an argument not given, not even None class Accessible(HasProperties): """base class for Parameter and Command""" kwds = None # is a dict if it might be used as Override def __init__(self, **kwds): super().__init__() self.init(kwds) def init(self, kwds): # do not use self.propertyValues.update here, as no invalid values should be # assigned to properties, even not before checkProperties for k, v in kwds.items(): self.setProperty(k, v) def inherit(self, cls, owner): for base in owner.__bases__: if hasattr(base, self.name): aobj = getattr(base, 'accessibles', {}).get(self.name) if aobj: if not isinstance(aobj, cls): raise ProgrammingError('%s %s.%s can not inherit from a %s' % (cls.__name__, owner.__name__, self.name, aobj.__class__.__name__)) # inherit from aobj for pname, value in aobj.propertyValues.items(): if pname not in self.propertyValues: self.propertyValues[pname] = value break def as_dict(self): return self.propertyValues def override(self, value=UNSET, **kwds): """return a copy, overridden by a bare attribute and/or some properties""" raise NotImplementedError def copy(self): """return a (deep) copy of ourselfs""" raise NotImplementedError def for_export(self): """prepare for serialisation""" raise NotImplementedError def __repr__(self): props = [] for k, prop in sorted(self.propertyDict.items()): v = self.propertyValues.get(k, prop.default) if v != prop.default: props.append('%s=%r' % (k, v)) return '%s(%s)' % (self.__class__.__name__, ', '.join(props)) class Parameter(Accessible): """defines a parameter :param description: description :param datatype: the datatype :param inherit: whether properties not given should be inherited :param kwds: optional properties """ # storage for Parameter settings + value + qualifiers description = Property( 'mandatory description of the parameter', TextType(), extname='description', mandatory=True) datatype = Property( 'datatype of the Parameter (SECoP datainfo)', DataTypeType(), extname='datainfo', mandatory=True) readonly = Property( 'not changeable via SECoP (default True)', BoolType(), extname='readonly', default=True, export='always') group = Property( 'optional parameter group this parameter belongs to', StringType(), extname='group', default='') visibility = Property( 'optional visibility hint', EnumType('visibility', user=1, advanced=2, expert=3), extname='visibility', default=1) constant = Property( 'optional constant value for constant parameters', ValueType(), extname='constant', default=None) default = Property( '''[internal] default (startup) value of this parameter if it can not be read from the hardware''', ValueType(), export=False, default=None) export = Property( '''[internal] export settings * False: not accessible via SECoP. * True: exported, name automatic. * a string: exported with custom name''', OrType(BoolType(), StringType()), export=False, default=True) poll = Property( '''[internal] polling indicator may be: * None (omitted): will be converted to True/False if handler is/is not None * False or 0 (never poll this parameter) * True or 1 (AUTO), converted to SLOW (readonly=False) DYNAMIC (*status* and *value*) or REGULAR (else) * 2 (SLOW), polled with lower priority and a multiple of pollinterval * 3 (REGULAR), polled with pollperiod * 4 (DYNAMIC), if BUSY, with a fraction of pollinterval, else polled with pollperiod ''', NoneOr(IntRange()), export=False, default=None) needscfg = Property( '[internal] needs value in config', NoneOr(BoolType()), export=False, default=None) optional = Property( '[internal] is this parameter optional?', BoolType(), export=False, settable=False, default=False) handler = Property( '[internal] overload the standard read and write functions', ValueType(), export=False, default=None, settable=False) initwrite = Property( '''[internal] write this parameter on initialization default None: write if given in config''', NoneOr(BoolType()), export=False, default=None, settable=False) # used on the instance copy only value = None timestamp = 0 readerror = None def __init__(self, description=None, datatype=None, inherit=True, *, unit=None, constant=None, **kwds): super().__init__(**kwds) if datatype is not None: if not isinstance(datatype, DataType): if isinstance(datatype, type) and issubclass(datatype, DataType): # goodie: make an instance from a class (forgotten ()???) datatype = datatype() else: raise ProgrammingError( 'datatype MUST be derived from class DataType!') self.datatype = datatype if 'default' in kwds: self.default = datatype(kwds['default']) if description is not None: self.description = inspect.cleandoc(description) # save for __set_name__ self._inherit = inherit self._unit = unit # for legacy code only self._constant = constant def __get__(self, instance, owner): # not used yet if instance is None: return self return instance.parameters[self.name].value def __set__(self, obj, value): obj.announceUpdate(self.name, value) def __set_name__(self, owner, name): self.name = name if self._inherit: self.inherit(Parameter, owner) # check for completeness missing_properties = [pname for pname in ('description', 'datatype') if pname not in self.propertyValues] if missing_properties: raise ProgrammingError('Parameter %s.%s needs a %s' % (owner.__name__, name, ' and a '.join(missing_properties))) if self._unit is not None: self.datatype.setProperty('unit', self._unit) if self._constant is not None: constant = self.datatype(self._constant) # The value of the `constant` property should be the # serialised version of the constant, or unset self.constant = self.datatype.export_value(constant) self.readonly = True if 'default' in self.propertyValues: # fixes in case datatype has changed try: self.datatype(self.default) except BadValueError: # clear default, if it does not match datatype self.propertyValues.pop('default') if self.export is True: if isinstance(self, PREDEFINED_ACCESSIBLES.get(name, type(None))): self.export = name else: self.export = '_' + name def copy(self): # deep copy, as datatype might be altered from config res = Parameter() res.name = self.name res.init(self.propertyValues) res.datatype = res.datatype.copy() return res def override(self, value=UNSET, **kwds): res = self.copy() res.init(kwds) if value is not UNSET: res.value = res.datatype(value) return res def export_value(self): return self.datatype.export_value(self.value) def for_export(self): return dict(self.exportProperties(), readonly=self.readonly) def getProperties(self): """get also properties of datatype""" super_prop = super().getProperties().copy() super_prop.update(self.datatype.getProperties()) return super_prop def setProperty(self, key, value): """set also properties of datatype""" if key in self.propertyDict: super().setProperty(key, value) else: self.datatype.setProperty(key, value) def checkProperties(self): super().checkProperties() self.datatype.checkProperties() class Command(Accessible): """decorator to turn a method into a command :param argument: the datatype of the argument or None :param result: the datatype of the result or None :param inherit: whether properties not given should be inherited :param kwds: optional properties """ description = Property( 'description of the Command', TextType(), extname='description', export=True, mandatory=True) group = Property( 'optional command group of the command.', StringType(), extname='group', export=True, default='') visibility = Property( 'optional visibility hint', EnumType('visibility', user=1, advanced=2, expert=3), extname='visibility', export=True, default=1) export = Property( '''[internal] export settings * False: not accessible via SECoP. * True: exported, name automatic. * a string: exported with custom name''', OrType(BoolType(), StringType()), export=False, default=True) optional = Property( '[internal] is the command optional to implement? (vs. mandatory)', BoolType(), export=False, default=False, settable=False) datatype = Property( "datatype of the command, auto generated from 'argument' and 'result'", DataTypeType(), extname='datainfo', export='always') argument = Property( 'datatype of the argument to the command, or None', NoneOr(DataTypeType()), export=False, mandatory=True) result = Property( 'datatype of the result from the command, or None', NoneOr(DataTypeType()), export=False, mandatory=True) func = None def __init__(self, argument=False, *, result=None, inherit=True, **kwds): super().__init__(**kwds) if result or kwds or isinstance(argument, DataType) or not callable(argument): # normal case if argument is False and result: argument = None if argument is not False: if isinstance(argument, (tuple, list)): # goodie: treat as TupleOf argument = TupleOf(*argument) self.argument = argument self.result = result else: # goodie: allow @Command instead of @Command() self.func = argument # this is the wrapped method! if argument.__doc__: self.description = inspect.cleandoc(argument.__doc__) self.name = self.func.__name__ self._inherit = inherit # save for __set_name__ def __set_name__(self, owner, name): self.name = name if self.func is None: raise ProgrammingError('Command %s.%s must be used as a method decorator' % (owner.__name__, name)) if self._inherit: self.inherit(Command, owner) self.datatype = CommandType(self.argument, self.result) if self.export is True: if isinstance(self, PREDEFINED_ACCESSIBLES.get(name, type(None))): self.export = name else: self.export = '_' + name def __get__(self, obj, owner=None): if obj is None: return self if not self.func: raise ProgrammingError('Command %s not properly configured' % self.name) return self.func.__get__(obj, owner) def __call__(self, func): if 'description' not in self.propertyValues and func.__doc__: self.description = inspect.cleandoc(func.__doc__) self.func = func return self def copy(self): res = Command() res.name = self.name res.func = self.func res.init(self.propertyValues) if res.argument: res.argument = res.argument.copy() if res.result: res.result = res.result.copy() res.datatype = CommandType(res.argument, res.result) return res def override(self, value=UNSET, **kwds): res = self.copy() res.init(kwds) if value is not UNSET: res.func = value return res def do(self, module_obj, argument): """perform function call :param module_obj: the module on which the command is to be executed :param argument: the argument from the do command :returns: the return value converted to the result type - when the argument type is TupleOf, the function is called with multiple arguments - when the argument type is StructOf, the function is called with keyworded arguments - the validity of the argument/s is/are checked """ func = self.__get__(module_obj) if self.argument: # validate argument = self.argument(argument) if isinstance(self.argument, TupleOf): res = func(*argument) elif isinstance(self.argument, StructOf): res = func(**argument) else: res = func(argument) else: if argument is not None: raise BadValueError('%s.%s takes no arguments' % (module_obj.__class__.__name__, self.name)) res = func() if self.result: return self.result(res) return None # silently ignore the result from the method def for_export(self): return self.exportProperties() def __repr__(self): result = super().__repr__() return result[:-1] + ', %r)' % self.func if self.func else result # list of predefined accessibles with their type PREDEFINED_ACCESSIBLES = dict( value=Parameter, status=Parameter, target=Parameter, pollinterval=Parameter, ramp=Parameter, user_ramp=Parameter, setpoint=Parameter, time_to_target=Parameter, unit=Parameter, # reserved name loglevel=Parameter, # reserved name mode=Parameter, # reserved name stop=Command, reset=Command, go=Command, abort=Command, shutdown=Command, communicate=Command, )