File: device_class.py

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# SPDX-FileCopyrightText: All Contributors to the PyTango project
# SPDX-License-Identifier: LGPL-3.0-or-later

"""
This is an internal PyTango module.
"""


__all__ = ("DeviceClass", "device_class_init")

__docformat__ = "restructuredtext"

import collections.abc

from tango._tango import (
    Except,
    DevFailed,
    DeviceClass,
    CmdArgType,
    DispLevel,
    UserDefaultAttrProp,
)
from tango.pyutil import Util

from tango.utils import is_pure_str, is_non_str_seq, seqStr_2_obj, obj_2_str, is_array

from tango.globals import get_class, get_class_by_class, get_constructed_class_by_class
from tango.attr_data import AttrData


class PropUtil:
    """An internal Property util class"""

    scalar_int_types = (
        CmdArgType.DevShort,
        CmdArgType.DevUShort,
        CmdArgType.DevLong,
        CmdArgType.DevULong,
    )

    scalar_long_types = (CmdArgType.DevLong64, CmdArgType.DevULong64)

    scalar_float_types = (
        CmdArgType.DevFloat,
        CmdArgType.DevDouble,
    )

    scalar_numerical_types = scalar_int_types + scalar_long_types + scalar_float_types

    scalar_str_types = (
        CmdArgType.DevString,
        CmdArgType.ConstDevString,
    )

    scalar_types = (
        scalar_numerical_types
        + scalar_str_types
        + (
            CmdArgType.DevBoolean,
            CmdArgType.DevEncoded,
            CmdArgType.DevUChar,
            CmdArgType.DevVoid,
        )
    )

    def __init__(self):
        self.db = None
        if Util._UseDb:
            self.db = Util.instance().get_database()

    def set_default_property_values(self, dev_class, class_prop, dev_prop):
        """
        set_default_property_values(self, dev_class, class_prop, dev_prop) -> None

            Sets the default property values

        Parameters :
            - dev_class : (DeviceClass) device class object
            - class_prop : (dict<str,>) class properties
            - dev_prop : (dict<str,>) device properties

        Return     : None
        """
        for name in class_prop:
            type = self.get_property_type(name, class_prop)
            val = self.get_property_values(name, class_prop)
            val = self.values2string(val, type)
            desc = self.get_property_description(name, class_prop)
            dev_class.add_wiz_class_prop(name, desc, val)

        for name in dev_prop:
            type = self.get_property_type(name, dev_prop)
            val = self.get_property_values(name, dev_prop)
            val = self.values2string(val, type)
            desc = self.get_property_description(name, dev_prop)
            dev_class.add_wiz_dev_prop(name, desc, val)

    def get_class_properties(self, dev_class, class_prop):
        """
        get_class_properties(self, dev_class, class_prop) -> None

                Returns the class properties

            Parameters :
                - dev_class : (DeviceClass) the DeviceClass object
                - class_prop : [in, out] (dict<str, None>) the property names. Will be filled
                               with property values

            Return     : None"""
        # initialize default values
        if class_prop == {} or not Util._UseDb:
            return

        # call database to get properties
        props = self.db.get_class_property(
            dev_class.get_name(), list(class_prop.keys())
        )

        # if value defined in database, store it
        for name in class_prop:
            if props[name]:
                type = self.get_property_type(name, class_prop)
                values = self.stringArray2values(props[name], type)
                self.set_property_values(name, class_prop, values)
            else:
                print(name + " property NOT found in database")

    def get_device_properties(self, dev, class_prop, dev_prop):
        """
        get_device_properties(self, dev, class_prop, dev_prop) -> None

                Returns the device properties

            Parameters :
                - dev : (DeviceImpl) the device object
                - class_prop : (dict<str, obj>) the class properties
                - dev_prop : [in,out] (dict<str, None>) the device property names

            Return     : None"""
        #    initialize default properties
        if dev_prop == {} or not Util._UseDb:
            return

        # Call database to get properties
        props = self.db.get_device_property(dev.get_name(), list(dev_prop.keys()))
        #    if value defined in database, store it
        for name in dev_prop:
            prop_value = props[name]
            if len(prop_value):
                data_type = self.get_property_type(name, dev_prop)
                values = self.stringArray2values(prop_value, data_type)
                if not self.is_empty_seq(values):
                    self.set_property_values(name, dev_prop, values)
                else:
                    #    Try to get it from class property
                    values = self.get_property_values(name, class_prop)
                    if not self.is_empty_seq(values):
                        if not self.is_seq(values):
                            values = [values]
                        data_type = self.get_property_type(name, class_prop)
                        values = self.stringArray2values(values, data_type)
                        if not self.is_empty_seq(values):
                            self.set_property_values(name, dev_prop, values)
            else:
                #    Try to get it from class property
                values = self.get_property_values(name, class_prop)
                if not self.is_empty_seq(values):
                    if not self.is_seq(values):
                        values = [values]
                    data_type = self.get_property_type(name, class_prop)
                    values = self.stringArray2values(values, data_type)
                    if not self.is_empty_seq(values):
                        self.set_property_values(name, dev_prop, values)

    def is_seq(self, v):
        """
        is_seq(self, v) -> bool

                Helper method. Determines if the object is a sequence

            Parameters :
                - v : (object) the object to be analysed

            Return     : (bool) True if the object is a sequence or False otherwise"""
        return isinstance(v, collections.abc.Sequence)

    def is_empty_seq(self, v):
        """
        is_empty_seq(self, v) -> bool

                Helper method. Determines if the object is an empty sequence

            Parameters :
                - v : (object) the object to be analysed

            Return     : (bool) True if the object is a sequence which is empty or False otherwise
        """
        return self.is_seq(v) and not len(v)

    def get_property_type(self, prop_name, properties):
        """
        get_property_type(self, prop_name, properties) -> CmdArgType

                Gets the property type for the given property name using the
                information given in properties

            Parameters :
                - prop_name : (str) property name
                - properties : (dict<str,data>) property data

            Return     : (CmdArgType) the tango type for the given property"""
        try:
            tg_type = properties[prop_name][0]
        except Exception:
            tg_type = CmdArgType.DevVoid
        return tg_type

    def set_property_values(self, prop_name, properties, values):
        """
        set_property_values(self, prop_name, properties, values) -> None

                Sets the property value in the properties

            Parameters :
                - prop_name : (str) property name
                - properties : (dict<str,obj>) [in,out] dict which will contain the value
                - values : (seq) the new property value

            Return     : None"""

        properties[prop_name][2] = values

    def get_property_values(self, prop_name, properties):
        """
        get_property_values(self, prop_name, properties) -> obj

                Gets the property value

            Parameters :
                - prop_name : (str) property name
                - properties : (dict<str,obj>) properties
            Return     : (obj) the value for the given property name"""
        tg_type = self.get_property_type(prop_name, properties)

        try:
            val = properties[prop_name][2]
        except Exception:
            val = []

        if is_pure_str(val):
            val = self.stringArray2values(val, tg_type)

        if is_array(tg_type) or (
            isinstance(val, collections.abc.Sequence) and not len(val)
        ):
            return val
        else:
            if is_non_str_seq(val):
                return val[0]
            else:
                return val

    def get_property_description(self, prop_name, properties):
        """
        get_property_description(self, prop_name, properties) -> obj

                Gets the property description

            Parameters :
                - prop_name : (str) property name
                - properties : (dict<str,obj>) properties
            Return     : (str) the description for the given property name"""
        return properties[prop_name][1]

    def stringArray2values(self, argin, argout_type):
        """internal helper method"""
        return seqStr_2_obj(argin, argout_type)

    def values2string(self, argin, argout_type):
        """internal helper method"""
        return obj_2_str(argin, argout_type)


def __DeviceClass__init__(self, name):
    DeviceClass.__init_orig__(self, name)
    try:
        pu = self.prop_util = PropUtil()
        self.py_dev_list = []
        pu.set_default_property_values(
            self, self.class_property_list, self.device_property_list
        )
        pu.get_class_properties(self, self.class_property_list)
        for prop_name in self.class_property_list:
            if not hasattr(self, prop_name):
                setattr(
                    self,
                    prop_name,
                    pu.get_property_values(prop_name, self.class_property_list),
                )
    except DevFailed as df:
        print(f"PyDS: {name}: A Tango error occurred in the constructor:")
        Except.print_exception(df)
    except Exception as e:
        print(f"PyDS: {name}: An error occurred in the constructor:")
        print(str(e))


def __DeviceClass__str__(self):
    return f"{self.__class__.__name__}({self.get_name()})"


def __DeviceClass__repr__(self):
    return f"{self.__class__.__name__}({self.get_name()})"


def __throw_create_attribute_exception(msg):
    """
    Helper method to throw DevFailed exception when inside
    create_attribute
    """
    Except.throw_exception("PyDs_WrongAttributeDefinition", msg, "create_attribute()")


def __throw_create_command_exception(msg):
    """
    Helper method to throw DevFailed exception when inside
    create_command
    """
    Except.throw_exception("PyDs_WrongCommandDefinition", msg, "create_command()")


def __DeviceClass__create_user_default_attr_prop(self, attr_name, extra_info):
    """for internal usage only"""
    p = UserDefaultAttrProp()
    for k, v in extra_info.items():
        k_lower = k.lower()
        method_name = f"set_{k_lower.replace(' ', '_')}"
        if hasattr(p, method_name):
            method = getattr(p, method_name)
            method(str(v))
        elif k == "delta_time":
            p.set_delta_t(str(v))
        elif k_lower not in ("display level", "polling period", "memorized"):
            name = self.get_name()
            msg = (
                f"Wrong definition of attribute {attr_name} in "
                f"class {name}\nThe object extra information '{k}' "
                f"is not recognized!"
            )
            self.__throw_create_attribute_exception(msg)
    return p


def __DeviceClass__attribute_factory(self, attr_list_wrapper):
    """
    for internal usage only!!!

    Note: attempts to do anything with attr_list_wrapper here are
    not 100% save and may result either in crash or memory leak !!!
    """

    for attr_name, attr_info in self.attr_list.items():
        if isinstance(attr_info, AttrData):
            attr_data = attr_info
        else:
            attr_data = AttrData(attr_name, self.get_name(), attr_info)
        if attr_data.forward:
            self._create_fwd_attribute(
                attr_list_wrapper, attr_data.attr_name, attr_data.att_prop
            )
        else:
            self._create_attribute(
                attr_list_wrapper,
                attr_data.attr_name,
                attr_data.attr_type,
                attr_data.attr_format,
                attr_data.attr_write,
                attr_data.dim_x,
                attr_data.dim_y,
                attr_data.display_level,
                attr_data.polling_period,
                attr_data.memorized,
                attr_data.hw_memorized,
                attr_data.alarm_event_implemented,
                attr_data.alarm_event_detect,
                attr_data.archive_event_implemented,
                attr_data.archive_event_detect,
                attr_data.change_event_implemented,
                attr_data.change_event_detect,
                attr_data.data_ready_event_implemented,
                attr_data.read_method_name,
                attr_data.write_method_name,
                attr_data.is_allowed_name,
                attr_data.att_prop,
            )


def __DeviceClass__command_factory(self):
    """for internal usage only"""
    name = self.get_name()
    class_info = get_class(name)
    deviceimpl_class = class_info[1]

    if not hasattr(deviceimpl_class, "init_device"):
        msg = (
            f"Wrong definition of class {name}\n"
            f"The init_device() method does not exist!"
        )
        Except.throw_exception("PyDs_WrongCommandDefinition", msg, "command_factory()")

    for cmd_name, cmd_info in self.cmd_list.items():
        __create_command(self, deviceimpl_class, cmd_name, cmd_info)


def __create_command(self, deviceimpl_class, cmd_name, cmd_info):
    """for internal usage only"""
    name = self.get_name()

    # check for well defined command info

    # check parameter
    if not isinstance(cmd_info, collections.abc.Sequence):
        msg = (
            f"Wrong data type for value for describing command {cmd_name} in "
            f"class {name}\nMust be a sequence with 2 or 3 elements"
        )
        __throw_create_command_exception(msg)

    if len(cmd_info) < 2 or len(cmd_info) > 3:
        msg = (
            f"Wrong number of argument for describing command {cmd_name} in "
            f"class {name}\nMust be a sequence with 2 or 3 elements"
        )
        __throw_create_command_exception(msg)

    param_info, result_info = cmd_info[0], cmd_info[1]

    if not isinstance(param_info, collections.abc.Sequence):
        msg = (
            f"Wrong data type in command argument for command {cmd_name} in "
            f"class {name}\nCommand parameter (first element) must be a sequence"
        )
        __throw_create_command_exception(msg)

    if len(param_info) < 1 or len(param_info) > 2:
        msg = (
            f"Wrong data type in command argument for command {cmd_name} in "
            f"class {name}\nSequence describing command parameters must contain "
            f"1 or 2 elements"
        )
        __throw_create_command_exception(msg)

    param_type = CmdArgType.DevVoid
    try:
        param_type = CmdArgType(param_info[0])
    except Exception:
        msg = (
            f"Wrong data type in command argument for command {cmd_name} in "
            f"class {name}\nCommand parameter type (first element in first "
            f"sequence) must be a tango.CmdArgType"
        )
        __throw_create_command_exception(msg)

    param_desc = ""
    if len(param_info) > 1:
        param_desc = param_info[1]
        if not is_pure_str(param_desc):
            msg = (
                f"Wrong data type in command parameter for command {cmd_name} in "
                f"class {name}\nCommand parameter description (second element "
                f"in first sequence), when given, must be a string"
            )
            __throw_create_command_exception(msg)

    # Check result
    if not isinstance(result_info, collections.abc.Sequence):
        msg = (
            f"Wrong data type in command result for command {cmd_name} in "
            f"class {name}\nCommand result (second element) must be a sequence"
        )
        __throw_create_command_exception(msg)

    if len(result_info) < 1 or len(result_info) > 2:
        msg = (
            f"Wrong data type in command result for command {cmd_name} in "
            f"class {name}\nSequence describing command result must contain "
            f"1 or 2 elements"
        )
        __throw_create_command_exception(msg)

    result_type = CmdArgType.DevVoid
    try:
        result_type = CmdArgType(result_info[0])
    except Exception:
        msg = (
            f"Wrong data type in command result for command {cmd_name} in "
            f"class {name}\nCommand result type (first element in second "
            f"sequence) must be a tango.CmdArgType"
        )
        __throw_create_command_exception(msg)

    result_desc = ""
    if len(result_info) > 1:
        result_desc = result_info[1]
        if not is_pure_str(result_desc):
            msg = (
                f"Wrong data type in command result for command {cmd_name} in "
                f"class {name}\nCommand parameter description (second element "
                f"in second sequence), when given, must be a string"
            )
            __throw_create_command_exception(msg)

    # If it is defined, get addictional dictionnary used for optional parameters
    display_level, default_command, polling_period, is_allowed = (
        DispLevel.OPERATOR,
        False,
        -1,
        None,
    )

    if len(cmd_info) == 3:
        extra_info = cmd_info[2]
        if not isinstance(extra_info, collections.abc.Mapping):
            msg = (
                f"Wrong data type in command information for command {cmd_name} in "
                f"class {name}\nCommand information (third element in sequence), "
                f"when given, must be a dictionary"
            )
            __throw_create_command_exception(msg)

        if len(extra_info) > 4:
            msg = (
                f"Wrong data type in command information for command {cmd_name} in "
                f"class {name}\nThe optional dictionary can not have more than "
                f"four elements"
            )
            __throw_create_command_exception(msg)

        for info_name, info_value in extra_info.items():
            info_name_lower = info_name.lower()
            if info_name_lower == "display level":
                try:
                    display_level = DispLevel(info_value)
                except Exception:
                    msg = (
                        f"Wrong data type in command information for command {cmd_name} in "
                        f"class {name}\nCommand information for display level is not a "
                        f"tango.DispLevel"
                    )
                    __throw_create_command_exception(msg)
            elif info_name_lower == "default command":
                if not is_pure_str(info_value):
                    msg = (
                        f"Wrong data type in command information for command {cmd_name} in "
                        f"class {name}\nCommand information for default command is not a "
                        f"string"
                    )
                    __throw_create_command_exception(msg)
                v = info_value.lower()
                default_command = v == "true"
            elif info_name_lower == "polling period":
                try:
                    polling_period = int(info_value)
                except Exception:
                    msg = (
                        f"Wrong data type in command information for command {cmd_name} in "
                        f"class {name}\nCommand information for polling period is not an "
                        f"integer"
                    )
                    __throw_create_command_exception(msg)
            elif info_name_lower == "is allowed":
                is_allowed = info_value
                if not is_pure_str(is_allowed):
                    msg = (
                        "Wrong data type in command information for command %s in "
                        "class %s\nCommand information for is allowed function name"
                        "is not an string" % (cmd_name, name)
                    )
                    __throw_create_command_exception(msg)
            elif info_name_lower == "is allowed green_mode":
                pass
            else:
                msg = (
                    f"Wrong data type in command information for command {cmd_name} in "
                    f"class {name}\nCommand information has unknown key "
                    f"{info_name}"
                )
                __throw_create_command_exception(msg)

    # check that the method to be executed exists
    try:
        cmd = getattr(deviceimpl_class, cmd_name)
        if not isinstance(cmd, collections.abc.Callable):
            msg = (
                f"Wrong definition of command {cmd_name} in "
                f"class {name}\nThe object exists in class but is not "
                f"a method!"
            )
            __throw_create_command_exception(msg)
    except AttributeError:
        msg = (
            f"Wrong definition of command {cmd_name} in "
            f"class {name}\nThe command method does not exist!"
        )
        __throw_create_command_exception(msg)

    if is_allowed is None:
        is_allowed_name = f"is_{cmd_name}_allowed"
    else:
        is_allowed_name = is_allowed

    try:
        is_allowed_function = getattr(deviceimpl_class, is_allowed_name)
        if not isinstance(is_allowed_function, collections.abc.Callable):
            msg = (
                f"Wrong definition of command {cmd_name} in "
                f"class {name}\nThe object '{is_allowed_name}' exists in class but is "
                f"not a method!"
            )
            __throw_create_command_exception(msg)
    except Exception:
        is_allowed_name = ""

    self._create_command(
        cmd_name,
        param_type,
        result_type,
        param_desc,
        result_desc,
        display_level,
        default_command,
        polling_period,
        is_allowed_name,
    )


def __DeviceClass__new_device(self, klass, dev_class, dev_name):
    return klass(dev_class, dev_name)


def __DeviceClass__device_factory(self, device_list):
    """for internal usage only"""

    klass = self.__class__
    klass_name = klass.__name__
    info, klass = get_class_by_class(klass), get_constructed_class_by_class(klass)

    if info is None:
        raise RuntimeError(f"Device class '{klass_name}' is not registered")

    if klass is None:
        raise RuntimeError(f"Device class '{klass_name}' as not been constructed")

    deviceClassClass, deviceImplClass, deviceImplName = info
    deviceImplClass._device_class_instance = klass

    tmp_dev_list = []
    for dev_name in device_list:
        device = self._new_device(deviceImplClass, klass, dev_name)
        self._add_device(device)
        tmp_dev_list.append(device)

    self.dyn_attr(tmp_dev_list)

    for dev in tmp_dev_list:
        if Util._UseDb and not Util._FileDb:
            self.export_device(dev)
        else:
            self.export_device(dev, dev.get_name())
    self.py_dev_list += tmp_dev_list


def __DeviceClass__create_device(self, device_name, alias=None, cb=None):
    """
    create_device(self, device_name, alias=None, cb=None) -> None

        Creates a new device of the given class in the database, creates a new
        DeviceImpl for it and calls init_device (just like it is done for
        existing devices when the DS starts up)

        An optional parameter callback is called AFTER the device is
        registered in the database and BEFORE the init_device for the
        newly created device is called

    Throws tango.DevFailed:
        - the device name exists already or
        - the given class is not registered for this DS.
        - the cb is not a callable

    New in PyTango 7.1.2

    Parameters :
        - device_name : (str) the device name
        - alias : (str) optional alias. Default value is None meaning do not create device alias
        - cb : (callable) a callback that is called AFTER the device is registered
               in the database and BEFORE the init_device for the newly created
               device is called. Typically you may want to put device and/or attribute
               properties in the database here. The callback must receive a parameter
               device_name (str). Default value is None meaning no callback

    Return     : None"""
    util = Util.instance()
    util.create_device(self.get_name(), device_name, alias=alias, cb=cb)


def __DeviceClass__delete_device(self, device_name):
    """
    delete_device(self, klass_name, device_name) -> None

        Deletes an existing device from the database and from this running
        server

        Throws tango.DevFailed:
            - the device name doesn't exist in the database
            - the device name doesn't exist in this DS.

    New in PyTango 7.1.2

    Parameters :
        - klass_name : (str) the device class name
        - device_name : (str) the device name

    Return     : None"""
    util = Util.instance()
    util.delete_device(self.get_name(), device_name)


def __DeviceClass__dyn_attr(self, device_list):
    """
    dyn_attr(self,device_list) -> None

        Default implementation does not do anything
        Overwrite in order to provide dynamic attributes

    Parameters :
        - device_list : (seq<DeviceImpl>) sequence of devices of this class

    Return     : None"""
    pass


def __DeviceClass__device_destroyer(self, name):
    """for internal usage only"""
    name = name.lower()
    for d in self.py_dev_list:
        dname = d.get_name().lower()
        if dname == name:
            dev_cl = d.get_device_class()
            # the internal C++ device_destroyer isn't case sensitive so we
            # use the internal DeviceImpl name to make sure the DeviceClass
            # finds it
            dev_cl._device_destroyer(d.get_name())
            self.py_dev_list.remove(d)
            return
    err_mess = "Device " + name + " not in Tango class device list!"
    Except.throw_exception(
        "PyAPI_CantDestroyDevice", err_mess, "DeviceClass.device_destroyer"
    )


def __DeviceClass__device_name_factory(self, dev_name_list):
    """
    device_name_factory(self, dev_name_list) ->  None

        Create device(s) name list (for no database device server).
        This method can be re-defined in DeviceClass sub-class for
        device server started without database. Its rule is to
        initialise class device name. The default method does nothing.

    Parameters :
        - dev_name_list : (seq<str>) sequence of devices to be filled

    Return     : None"""
    pass


def device_class_init():
    DeviceClass.class_property_list = {}
    DeviceClass.device_property_list = {}
    DeviceClass.cmd_list = {}
    DeviceClass.attr_list = {}
    DeviceClass.__init_orig__ = DeviceClass.__init__
    DeviceClass.__init__ = __DeviceClass__init__
    DeviceClass.__str__ = __DeviceClass__str__
    DeviceClass.__repr__ = __DeviceClass__repr__
    DeviceClass._create_user_default_attr_prop = (
        __DeviceClass__create_user_default_attr_prop
    )
    DeviceClass._attribute_factory = __DeviceClass__attribute_factory
    DeviceClass._command_factory = __DeviceClass__command_factory
    DeviceClass._new_device = __DeviceClass__new_device

    DeviceClass.device_factory = __DeviceClass__device_factory
    DeviceClass.create_device = __DeviceClass__create_device
    DeviceClass.delete_device = __DeviceClass__delete_device
    DeviceClass.dyn_attr = __DeviceClass__dyn_attr
    DeviceClass.device_destroyer = __DeviceClass__device_destroyer
    DeviceClass.device_name_factory = __DeviceClass__device_name_factory