Source Code for Package ndg.xacml.parsers

 1  """NDG XACML parsers package  
 2   
 3  NERC DataGrid 
 4  """ 
 5  __author__ = "P J Kershaw" 
 6  __date__ = "15/03/10" 
 7  __copyright__ = "(C) 2010 Science and Technology Facilities Council" 
 8  __contact__ = "Philip.Kershaw@stfc.ac.uk" 
 9  __license__ = "BSD - see LICENSE file in top-level directory" 
10  __contact__ = "Philip.Kershaw@stfc.ac.uk" 
11  __revision__ = "$Id: __init__.py 7955 2011-12-21 18:29:45Z rwilkinson $" 
12  import logging 
13  log = logging.getLogger(__name__) 
14  from abc import ABCMeta, abstractmethod 
15   
16  from ndg.xacml import XacmlError 
17  from ndg.xacml.core import XacmlCoreBase 
18   
19       
20 -class XMLParseError(XacmlError): 
21      """XACML package XML Parsing error""" 
22   
23   
24 -class AbstractReader(object): 
25      """Abstract base class for XACML reader""" 
26      __metaclass__ = ABCMeta 
27       
28      @classmethod 
29 -    def __subclasshook__(cls, C): 
30          """Derived class must implement __call__""" 
31          if cls is AbstractReader: 
32              if any("__call__" in B.__dict__ for B in C.__mro__): 
33                  return True 
34               
35          return NotImplemented 
36           
37      @abstractmethod 
38 -    def __call__(self, obj, common): 
39          """Abstract Parse XACML method 
40          @raise NotImplementedError:  
41          """ 
42          raise NotImplementedError() 
43       
44      @classmethod 
45 -    def parse(cls, obj, common): 
46          """Parse from input object and return new XACML object 
47          @param obj: input source - file name, stream object or other 
48          @type obj: string, stream or other 
49          @return: new XACML object 
50          @rtype: XacmlCoreBase sub type 
51          """ 
52          reader = cls() 
53          return reader(obj, common) 
54       
55       
56 -class AbstractReaderFactory(object): 
57      """Abstract base class XACML reader factory""" 
58      __metaclass__ = ABCMeta 
59       
60      @classmethod 
61      @abstractmethod 
62 -    def getReader(cls, xacmlType): 
63          """Get the reader class for the given XACML input type 
64          @param xacmlType: XACML type to retrieve a reader for 
65          @type xacmlType: ndg.xaml.core.XacmlCoreBase derived 
66          @return: reader class 
67          @rtype: ndg.xacml.parsers.AbstractReader derived type 
68          """ 
69          if not issubclass(xacmlType, XacmlCoreBase): 
70              raise TypeError('Expecting %r derived class for getReader method; ' 
71                              'got %r' % (XacmlCoreBase, xacmlType)) 
72