"""
Type converter to/from vAPI runtime data model to Python native data model
"""
__author__ = 'VMware, Inc.'
__copyright__ = 'Copyright (c) 2015-2016 VMware, Inc. All rights reserved.'
import logging
import six
from vmware.vapi.bindings.type import (
    BindingTypeVisitor, OptionalType, MAP_KEY_FIELD,
    MAP_VALUE_FIELD)
from vmware.vapi.bindings.enum import Enum
from vmware.vapi.bindings.error import (VapiError, UnresolvedError)
from vmware.vapi.bindings.struct import VapiStruct
from vmware.vapi.bindings.datetime_helper import DateTimeConverter
from vmware.vapi.bindings.uri_helper import URIValidator
from vmware.vapi.data.serializers.python import build_data_value
from vmware.vapi.exception import CoreException
from vmware.vapi.lib.converter import Converter
from vmware.vapi.data.value import DataValue, StructValue
from vmware.vapi.l10n.runtime import message_factory
logger = logging.getLogger(__name__)
[docs]class PythonToVapiVisitor(BindingTypeVisitor):  # pylint: disable=W0223
    """
    Visitor to convert from Python native value to vAPI DataValue
    """
    def __init__(self, value):
        """
        Initialize PythonToVapiVisitor
        :type  value: :class:`object`
        :param value: Native python value
        """
        self._in_value = value
        self._out_value = None
        self._dispatch_map = {
            'VoidType': self.visit_void,
            'IntegerType': self.visit_primitive,
            'DoubleType': self.visit_primitive,
            'StringType': self.visit_primitive,
            'SecretType': self.visit_primitive,
            'BooleanType': self.visit_primitive,
            'BlobType': self.visit_primitive,
            'OptionalType': self.visit_optional,
            'ListType': self.visit_list,
            'SetType': self.visit_set,
            'MapType': self.visit_map,
            'StructType': self.visit_struct,
            'ErrorType': self.visit_error,
            'ReferenceType': self.visit_reference,
            'OpaqueType': self.visit_opaque,
            'DynamicStructType': self.visit_dynamic_struct,
            'AnyErrorType': self.visit_any_error,
            'DateTimeType': self.visit_date_time,
            'URIType': self.visit_uri,
            'EnumType': self.visit_enum,
            'IdType': self.visit_primitive,
        }
        BindingTypeVisitor.__init__(self)
[docs]    def visit(self, typ):
        class_name = typ.__class__.__name__
        method = self._dispatch_map[class_name]
        method(typ)
 
[docs]    def get_out_value(self):
        """
        Returns the vAPI DataValue converted from the Python native value
        :rtype: :class:`vmware.vapi.data.value.DataValue`
        :return: vAPI DataValue
        """
        return self._out_value
 
[docs]    def visit_primitive(self, typ):
        """
        Visit a primitive type python value
        :type  typ: :class:`vmware.vapi.bindings.type.BindingType`
        :param typ: Binding type of the value
        """
        self._out_value = typ.definition.new_value(self._in_value)
 
[docs]    def visit_void(self, typ):
        """
        Visit a void value (i.e. None)
        :type  typ: :class:`vmware.vapi.bindings.type.VoidType`
        :param typ: Binding type of the value
        """
        if self._in_value is not None:
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.voiddef.expect.null',
                type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
        self._out_value = typ.definition.new_value()
 
[docs]    def visit_opaque(self, typ):
        """
        Visit an opaque value. Don't do any conversion.
        :type  typ: :class:`vmware.vapi.bindings.type.OpaqueType`
        :param typ: Binding type of the value
        """
        if not isinstance(self._in_value, DataValue):
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.python.type',
                 DataValue.__name__, type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
        self._out_value = self._in_value
 
[docs]    def visit_list(self, typ):
        """
        Visit a list value
        :type  typ: :class:`vmware.vapi.bindings.type.ListType`
        :param typ: Binding type of the value
        """
        in_value = self._in_value
        out_value = typ.definition.new_value()
        elt_typ = typ.element_type
        for elt_value in in_value:
            self._in_value = elt_value
            self.visit(elt_typ)
            out_value.add(self._out_value)
        self._in_value = in_value
        self._out_value = out_value
 
[docs]    def visit_set(self, typ):
        """
        Visit a python set
        :type  typ: :class:`vmware.vapi.bindings.type.SetType`
        :param typ: Binding type of the value
        """
        if not isinstance(self._in_value, set) and not isinstance(self._in_value, frozenset):
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.invalid',
                'set', type(self._in_value))
            logger.debug(msg)
            raise CoreException(msg)
        self.visit_list(typ)
 
[docs]    def visit_map(self, typ):
        """
        Visit a python dict
        :type  typ: :class:`vmware.vapi.bindings.type.MapType`
        :param typ: Binding type of the value
        """
        in_value = self._in_value
        out_value = typ.definition.new_value()
        struct_def = typ.definition.element_type
        for k, v in six.iteritems(in_value):
            struct_val = struct_def.new_value()
            self._in_value = k
            self.visit(typ.key_type)
            struct_val.set_field(MAP_KEY_FIELD, self._out_value)
            self._in_value = v
            self.visit(typ.value_type)
            struct_val.set_field(MAP_VALUE_FIELD, self._out_value)
            out_value.add(struct_val)
        self._in_value = in_value
        self._out_value = out_value
 
    def _visit_vapi_struct(self, typ):
        """
        Visit an instance of VapiStruct class
        :type  typ: :class:`vmware.vapi.bindings.type.StructType`
        :param typ: Binding type of the value
        :rtype: :class:`vmware.vapi.data.value.DataValue`
        :return: vAPI Data value
        """
        # Check if it is the expected struct class
        expected_name = typ.name
        actual_name = self._in_value.get_binding_type().name
        # TODO: compare the types instead of names.
        if expected_name != actual_name:
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.struct.class',
                expected_name, actual_name)
            logger.debug(msg)
            raise CoreException(msg)
        in_value = self._in_value
        out_value = typ.definition.new_value()
        field_names = typ.get_field_names()
        for field in field_names:
            try:
                self._in_value = in_value.get_field(field)
                # If self._in_value is None and field type is not
                # optional, raise an error
                field_type = typ.get_field(field)
                if (not isinstance(field_type, OptionalType) and
                        self._in_value is None):
                    raise AttributeError
            except AttributeError:
                msg = message_factory.get_message(
                    'vapi.bindings.typeconverter.struct.missing.field',
                    field, typ.name)
                logger.debug(msg)
                raise CoreException(msg)
            try:
                self.visit(typ.get_field(field))
            except Exception as e:
                msg = message_factory.get_message(
                    'vapi.bindings.typeconverter.struct.invalid.field',
                    field, typ.name)
                logger.debug(msg)
                raise CoreException(msg, e)
            out_value.set_field(field, self._out_value)
        self._in_value = in_value
        self._out_value = out_value
    def _visit_python_dict(self, typ):
        """
        Visit an instance of Python native dictionary
        :type  typ: :class:`vmware.vapi.bindings.type.StructType`
        :param typ: Binding type of the value
        :rtype: :class:`vmware.vapi.data.value.DataValue`
        :return: vAPI Data value
        """
        in_value = self._in_value
        out_value = typ.definition.new_value()
        field_names = typ.get_field_names()
        for field in field_names:
            field_type = typ.get_field(field)
            try:
                self._in_value = in_value[field]
            except KeyError:
                if isinstance(field_type, OptionalType):
                    # If the field is optional, then tolerate
                    # the absence of it in the dictionary
                    self._in_value = None
                else:
                    msg = message_factory.get_message(
                        'vapi.bindings.typeconverter.dict.missing.key',
                        field)
                    logger.debug(msg)
                    raise CoreException(msg)
            self.visit(field_type)
            out_value.set_field(field, self._out_value)
        self._in_value = in_value
        self._out_value = out_value
[docs]    def visit_struct(self, typ):
        """
        Visit a struct value
        :type  typ: :class:`vmware.vapi.bindings.type.StructType`
        :param typ: Binding type of the value
        """
        if isinstance(self._in_value, VapiStruct):
            self._visit_vapi_struct(typ)
            # Validating the constraints in the struct value
            # before sending it over the wire. The validation does
            # not happen during initialization of VapiStruct or
            # StructValue
            self._in_value.validate_struct_value(self._out_value)
        elif isinstance(self._in_value, dict):
            self._visit_python_dict(typ)
        else:
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.struct.type',
                type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
 
[docs]    def visit_error(self, typ):
        """
        Visit an error value
        :type  typ: :class:`vmware.vapi.bindings.type.ErrorType`
        :param typ: Binding type of the value
        """
        if isinstance(self._in_value, VapiError):
            self._visit_vapi_struct(typ)
        else:
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.error.type',
                type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
 
[docs]    def visit_dynamic_struct(self, typ):
        """
        Visit any struct value
        :type  typ: :class:`vmware.vapi.bindings.type.DynamicStructType`
        :param typ: Binding type of the value
        """
        if self._in_value.__class__.__name__ == 'VapiStruct':
            self._out_value = self._in_value.get_struct_value()
        elif self._in_value.__class__.__name__ == 'VapiError':
            self._out_value = self._in_value.get_error_value()
        elif isinstance(self._in_value, VapiStruct):
            self._visit_vapi_struct(self._in_value.get_binding_type())
        elif isinstance(self._in_value, StructValue):
            self._out_value = self._in_value
        elif isinstance(self._in_value, dict):
            self._out_value = build_data_value(self._in_value, typ.definition)
        else:
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.python.type',
                 StructValue.__name__, type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
 
[docs]    def visit_any_error(self, typ):
        """
        Visit any error value
        :type  typ: :class:`vmware.vapi.bindings.type.AnyErrorType`
        :param typ: Binding type of the value
        """
        if isinstance(self._in_value, UnresolvedError):
            self._out_value = self._in_value.get_error_value()
        elif isinstance(self._in_value, VapiError):
            self._visit_vapi_struct(self._in_value.get_binding_type())
        else:
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.python.type',
                 VapiError.__name__, type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
 
[docs]    def visit_optional(self, typ):
        """
        Visit an optional value
        :type  typ: :class:`vmware.vapi.bindings.type.OptionalType`
        :param typ: Binding type of the value
        """
        if self._in_value is None:
            self._out_value = typ.definition.new_value()
        else:
            self.visit(typ.element_type)
            self._out_value = typ.definition.new_value(self._out_value)
 
[docs]    def visit_date_time(self, typ):
        """
        Visit a datetime value
        :type  typ: :class:`vmware.vapi.bindings.type.DateTimeType`
        :param typ: Binding type of the value
        """
        dt_str = DateTimeConverter.convert_from_datetime(self._in_value)
        self._out_value = typ.definition.new_value(dt_str)
 
[docs]    def visit_uri(self, typ):
        """
        Visit an URI value
        :type  typ: :class:`vmware.vapi.bindings.type.UriType`
        :param typ: Binding type of the value
        """
        URIValidator.validate(self._in_value)
        self._out_value = typ.definition.new_value(self._in_value)
 
[docs]    def visit_reference(self, typ):
        """
        Visit a reference type
        :type  typ: :class:`vmware.vapi.bindings.type.ReferenceType`
        :param typ: Binding type of the value
        """
        self.visit(typ.resolved_type)
 
[docs]    def visit_enum(self, typ):
        """
        Visit a enum type python value
        :type  typ: :class:`vmware.vapi.bindings.type.EnumType`
        :param typ: Binding type of the value
        """
        # If the binding type is EnumType, we will accept either
        # a plain string (or) a class variable of
        # :class:`vmware.vapi.bindings.enum.Enum` type.
        # String will be sent when the user invoked an API call
        # by sending a plain dictionary object (deserialized
        # from a human readable JSON).
        # Enum will be sent when the user use a language binding type
        # to invoke an operation.
        if not isinstance(self._in_value, six.string_types):
            msg = message_factory.get_message(
                'vapi.bindings.typeconverter.unexpected.python.type',
                typ.name, type(self._in_value).__name__)
            logger.debug(msg)
            raise CoreException(msg)
        if isinstance(self._in_value, Enum):
            # Check if it is the expected enum class
            expected_name = typ.name
            actual_name = self._in_value.get_binding_type().name
            # TODO: compare the types instead of names.
            if expected_name != actual_name:
                msg = message_factory.get_message(
                    'vapi.bindings.typeconverter.unexpected.enum.type',
                    expected_name, actual_name)
                logger.debug(msg)
                raise CoreException(msg)
        # Convert from vmware.vapi.bindings.Enum instance to string value
        enum_string_value = str(self._in_value)
        self._out_value = typ.definition.new_value(enum_string_value)
  
[docs]class VapiToPythonVisitor(BindingTypeVisitor):  # pylint: disable=W0223
    """
    Visitor to convert from vAPI DataValue to Python native value
    """
    def __init__(self, value, resolver):
        """
        Initialize VapiToPythonVisitor
        :type  value: :class:`vmware.vapi.data.value.DataValue`
        :param value: vAPI DataValue to be converted
        :type  resolver: :class:`vmware.vapi.bindings.common.NameToTypeResolver` or
            ``None``
        :param resolver: Type resolver
        """
        self._in_value = value
        self._resolver = resolver
        self._out_value = None
        self._dispatch_map = {
            'VoidType': self.visit_void,
            'IntegerType': self.visit_primitive,
            'DoubleType': self.visit_primitive,
            'StringType': self.visit_string,
            'SecretType': self.visit_primitive,
            'BooleanType': self.visit_primitive,
            'BlobType': self.visit_primitive,
            'OptionalType': self.visit_optional,
            'ListType': self.visit_list,
            'SetType': self.visit_set,
            'MapType': self.visit_map,
            'StructType': self.visit_struct,
            'ErrorType': self.visit_error,
            'ReferenceType': self.visit_reference,
            'OpaqueType': self.visit_opaque,
            'DynamicStructType': self.visit_dynamic_struct,
            'AnyErrorType': self.visit_any_error,
            'DateTimeType': self.visit_date_time,
            'URIType': self.visit_uri,
            'EnumType': self.visit_enum,
            'IdType': self.visit_primitive,
        }
        BindingTypeVisitor.__init__(self)
[docs]    def visit(self, typ):
        class_name = typ.__class__.__name__
        method = self._dispatch_map[class_name]
        method(typ)
 
[docs]    def get_out_value(self):
        """
        Returns the Python native value converted from the vAPI DataValue
        :rtype: :class:`object`
        :return: Native python value
        """
        return self._out_value
 
[docs]    def visit_primitive(self, typ):  # pylint: disable=W0613
        """
        Visit one of the primitive DataValues
        :type  typ: :class:`vmware.vapi.bindings.type.BindingType`
        :param typ: Binding type of the value
        """
        self._out_value = self._in_value.value
 
[docs]    def visit_void(self, typ):
        """
        Since there is no VoidValue, just return None
        :type  typ: :class:`vmware.vapi.bindings.type.VoidType`
        :param typ: Binding type of the value
        """
        self._out_value = None
 
[docs]    def visit_string(self, typ):
        """
        Visit StringValue
        :type  typ: :class:`vmware.vapi.bindings.type.StringType`
        :param typ: Binding type of the value
        """
        try:
            self._out_value = str(self._in_value.value)
        except UnicodeError:
            self._out_value = self._in_value.value
 
[docs]    def visit_opaque(self, typ):
        """
        Since there is no OpaqueValue, don't do any conversion
        :type  typ: :class:`vmware.vapi.bindings.type.OpaqueType`
        :param typ: Binding type of the value
        """
        self._out_value = self._in_value
 
    def _visit_list_element(self, value, typ):
        """
        Visit a ListValue element
        :type  value: :class:`vmware.vapi.data.value.DataValue`
        :param value: element value
        :type  typ: :class:`vmware.vapi.bindings.type.ListType`
        :param typ: Binding type of the element
        """
        self._in_value = value
        self.visit(typ)
        return self._out_value
[docs]    def visit_list(self, typ):
        """
        Visit a ListValue
        :type  typ: :class:`vmware.vapi.bindings.type.ListType`
        :param typ: Binding type of the value
        """
        elt_typ = typ.element_type
        in_value = self._in_value
        self._out_value = [self._visit_list_element(elt_value, elt_typ)
                           for elt_value in in_value]
        self._in_value = in_value
 
[docs]    def visit_set(self, typ):
        """
        Visit a List Value. This ListValue must represent a set i.e. there must not be any duplicate elements
        :type  typ: :class:`vmware.vapi.bindings.type.SetType`
        :param typ: Binding type of the value
        """
        elt_typ = typ.element_type
        in_value = self._in_value
        out_value = set()
        for elt_value in in_value:
            elt = self._visit_list_element(elt_value, elt_typ)
            if elt in out_value:
                msg = message_factory.get_message(
                    'vapi.bindings.typeconverter.set.duplicate.element',
                    elt)
                logger.debug(msg)
                raise CoreException(msg)
            out_value.add(elt)
        self._out_value = out_value
        self._in_value = in_value
 
[docs]    def visit_map(self, typ):
        """
        Visit a List Value. This ListValue must represent a map. Each element
        of the ListValue is a StructValue with two fields, namely 'key' and 'value'.
        The 'key' field represents the key of the map and the 'value' field
        represents the value of the map. Also, since this represents a map, there
        should not be duplicate keys.
        :type  typ: :class:`vmware.vapi.bindings.type.MapType`
        :param typ: Binding type of the value
        """
        in_value = self._in_value
        key_typ = typ.key_type
        value_typ = typ.value_type
        out_value = {}
        for elt_value in in_value:
            key = self._visit_struct_field(elt_value.get_field(MAP_KEY_FIELD),
                                           key_typ)
            if key in out_value:
                msg = message_factory.get_message(
                    'vapi.bindings.typeconverter.map.duplicate.key',
                    key)
                logger.debug(msg)
                raise CoreException(msg)
            value = self._visit_struct_field(elt_value.get_field(MAP_VALUE_FIELD),
                                             value_typ)
            out_value[key] = value
        self._out_value = out_value
        self._in_value = in_value
 
    def _visit_struct_field(self, value, typ):
        """
        Visit a field of a StructValue
        :type  value: :class:`vmware.vapi.data.value.DataValue`
        :param value: field value
        :type  typ: :class:`vmware.vapi.bindings.type.StructType`
        :param typ: Binding type of the struct field
        """
        self._in_value = value
        self.visit(typ)
        return self._out_value
[docs]    def visit_struct(self, typ):
        """
        Visit StructValue
        :type  typ: :class:`vmware.vapi.bindings.type.StructType`
        :param typ: Binding type of the value
        """
        in_value = self._in_value
        out_value = {}
        typ_field_names = typ.get_field_names()
        value_field_names = in_value.get_field_names()
        for field_name in typ_field_names:
            pep_name = Converter.canonical_to_pep(field_name)
            field_type = typ.get_field(field_name)
            # When the request is converted from DataValue to Native value
            # on the server side:
            # - if the client - server version matches: we wont hit this case
            # - if new client talks to old server, runtime would have
            #   raised InvalidArgument error if there are unexpected optional
            #   fields
            # - if old client talks to new server, runtime adds the missing
            #   optional fields, so we wont hit this case
            #
            # When the response is converted from DataValue to Native value
            # on the client side:
            # - if the client - server version matches: we wont hit this case
            # - if new client talks to old server,  client bindings should
            #   tolerate the absence of expected optional properties. So,
            #   we have to set it to None!
            # - if old client talks to new server, we will visit all the known
            #   fields here and the unexpected fields are added to the VapiStruct
            #   object
            if (isinstance(field_type, OptionalType) and
                    not in_value.has_field(field_name)):
                out_value[pep_name] = None
            else:
                out_value[pep_name] = self._visit_struct_field(
                    in_value.get_field(field_name), field_type)
        self._in_value = in_value
        struct_class = typ.binding_class
        if struct_class is not None:
            struct_class.validate_struct_value(self._in_value)
            self._out_value = struct_class(**out_value)
            # Fields present in struct value but not in struct binding type.
            unexpected_field_names = set(value_field_names) - set(typ_field_names)
            if unexpected_field_names:
                unexpected_fields = {}
                for field_name in unexpected_field_names:
                    unexpected_fields[field_name] = in_value.get_field(field_name)
                self._out_value._set_unexpected_fields(unexpected_fields)  # pylint: disable=E1103,W0212
        else:
            self._out_value = out_value
 
[docs]    def visit_dynamic_struct(self, typ):
        """
        Visit StructValue to convert it into the base VapiStruct
        :type  typ: :class:`vmware.vapi.bindings.type.DynamicStructType`
        :param typ: Binding type of the value
        """
        self._out_value = VapiStruct(struct_value=self._in_value)
 
[docs]    def visit_any_error(self, typ):
        """
        Visit ErrorValue to convert it into the base VapiError
        :type  typ: :class:`vmware.vapi.bindings.type.AnyErrorType`
        :param typ: Binding type of the value
        """
        typ = self._resolver and self._resolver.resolve(self._in_value.name)
        if typ is None:
            self._out_value = UnresolvedError({}, self._in_value)
        else:
            typ.accept(self)
 
[docs]    def visit_error(self, typ):
        """
        Visit ErrorValue
        :type  typ: :class:`vmware.vapi.bindings.type.ErrorType`
        :param typ: Binding type of the value
        """
        self.visit_struct(typ)
 
[docs]    def visit_optional(self, typ):
        """
        Visit OptionalValue
        :type  typ: :class:`vmware.vapi.bindings.type.OptionalType`
        :param typ: Binding type of the value
        """
        if self._in_value.is_set():
            self._in_value = self._in_value.value
            self.visit(typ.element_type)
        else:
            self._out_value = None
 
[docs]    def visit_date_time(self, typ):
        """
        Visit a datetime value
        :type  typ: :class:`vmware.vapi.bindings.type.DateTimeType`
        :param typ: Binding type of the value
        """
        self._out_value = DateTimeConverter.convert_to_datetime(
            self._in_value.value)
 
[docs]    def visit_uri(self, typ):
        """
        Visit an URI value
        :type  typ: :class:`vmware.vapi.bindings.type.UriType`
        :param typ: Binding type of the value
        """
        uri_string = self._in_value.value
        URIValidator.validate(uri_string)
        self._out_value = uri_string
 
[docs]    def visit_enum(self, typ):
        """
        Visit an Enum value
        :type  typ: :class:`vmware.vapi.bindings.type.EnumType`
        :param typ: Binding type of the value
        """
        enum_string = self._in_value.value
        if typ.binding_class:
            try:
                self._out_value = getattr(typ.binding_class, enum_string)
            except AttributeError:
                self._out_value = typ.binding_class(enum_string)
        else:
            self._out_value = Enum(enum_string)
 
[docs]    def visit_reference(self, typ):
        """
        Visit a reference type
        :type  typ: :class:`vmware.vapi.bindings.type.ReferenceType`
        :param typ: Binding type of the value
        """
        self.visit(typ.resolved_type)
  
[docs]class TypeConverter(object):
    """
    Converter class that converts values from vAPI data model to Python native
    data model
    """
    @staticmethod
[docs]    def convert_to_python(vapi_val, binding_type, resolver=None):
        """
        Converts vAPI DataValue to Python native value
        :type  vapi_val: :class:`vmware.vapi.data.value.DataValue`
        :param vapi_val: vAPI DataValue to be converted
        :type  binding_type: :class:`vmware.vapi.bindings.type.BindingType`
        :param binding_type: BindingType for the value
        :type  resolver: :class:`vmware.vapi.bindings.common.NameToTypeResolver` or
            ``None``
        :param resolver: Type resolver
        :rtype: :class:`object`
        :return: Python native value
        """
        visitor = VapiToPythonVisitor(vapi_val, resolver)
        binding_type.accept(visitor)
        return visitor.get_out_value()
 
    @staticmethod
[docs]    def convert_to_vapi(py_val, binding_type):
        """
        Converts Python native value to vAPI DataValue
        :type  py_val: :class:`object`
        :param py_val: Python native value to be converted
        :type  binding_type: :class:`vmware.vapi.bindings.type.BindingType`
        :param binding_type: BindingType for the value
        :rtype: :class:`vmware.vapi.data.value.DataValue`
        :return: vAPI DataValue
        """
        visitor = PythonToVapiVisitor(py_val)
        binding_type.accept(visitor)
        return visitor.get_out_value()