source: TI12-security/trunk/NDG_XACML/ndg/xacml/core/expression.py @ 6753

"""NDG Security Expression type definition

NERC DataGrid Project
"""
__author__ = "P J Kershaw"
__date__ = "25/02/10"
__copyright__ = "(C) 2010 Science and Technology Facilities Council"
__contact__ = "Philip.Kershaw@stfc.ac.uk"
__license__ = "BSD - see LICENSE file in top-level directory"
__contact__ = "Philip.Kershaw@stfc.ac.uk"
__revision__ = "$Id: $"
from ndg.xacml.core import PolicyComponent


class Expression(PolicyComponent):
    """XACML Expression type"""
    ELEMENT_LOCAL_NAME = None
    DATA_TYPE_ATTRIB_NAME = 'DataType'
    
    __slots__ = ('__dataType', )
    
    def __init__(self):
        self.__dataType = None
        
    def _get_dataType(self):
        return self.__dataType

    def _set_dataType(self, value):
        if not isinstance(value, basestring):
            raise TypeError('Expecting %r type for "dataType" '
                            'attribute; got %r' % (basestring, type(value)))
            
        self.__dataType = value   

    dataType = property(_get_dataType, _set_dataType, None, 
                        "expression value data type")