xml_marshaller: add support for Python 3

setup.py

@@ -33,6 +33,6 @@ setup(name=name,
       package_dir={'': 'src'},
       include_package_data=True,
       zip_safe=False,
-      install_requires=['lxml',],
+      install_requires=['lxml','six'],
       test_suite='xml_marshaller',
       )

src/xml_marshaller/tests/test_xml_marshaller.py

@@ -3,7 +3,7 @@ import unittest
 import xml_marshaller
 from xml_marshaller.xml_marshaller import load, loads, dump, dumps, dump_ns,\
                                           dumps_ns
-from StringIO import StringIO
+from io import BytesIO
 from lxml import etree
 import pkg_resources
 
@@ -42,13 +42,10 @@ class TestXMLMarhsaller(unittest.TestCase):
       # Disabled for xml with namespaces.
       # Because URI is not predictable
       return
-    if not isinstance(xml_data, str):
-      xml_string = xml_data.read()
-      xml_data.seek(0)
-    else:
-      xml_string = xml_data
+    if not isinstance(xml_data, bytes):
+      xml_data = xml_data.getvalue().decode("utf-8")
 
-    document_tree = etree.fromstring(xml_string)
+    document_tree = etree.fromstring(xml_data)
     is_validated = xmlschema.validate(document_tree)
     log = xmlschema.error_log
     error = log.last_error
@@ -57,14 +54,14 @@ class TestXMLMarhsaller(unittest.TestCase):
   def test_string_serialisation(self):
     """
     """
-    data_list = [None, 1, pow(2, 123L), 19.72, 1+5j,
-                 "here is a string & a <fake tag>",
+    data_list = [None, 1, 1<<123, 19.72, 1+5j,
+                 b"here is a string & a <fake tag>",
                  (1, 2, 3),
-                 ['alpha', 'beta', 'gamma', [None, 1, pow(2, 123L), 19.72,
-                                             1+5j, "& a <fake tag>"]],
-                 {'key': 'value', 1: 2},
-                 'éàù^ç'.decode('utf-8'),
-                 set(('a', 1,)),
+                 [b'alpha', b'beta', b'gamma', [None, 1, 1<<123, 19.72,
+                                             1+5j, b"& a <fake tag>"]],
+                 {b'key': b'value', 1: 2},
+                 u'éàù^ç',
+                 {b'a', 1},
                  True,
                  False,
                 ]
@@ -80,14 +77,14 @@ class TestXMLMarhsaller(unittest.TestCase):
   def test_file_serialisation(self):
     """
     """
-    data_list = [None, 1, pow(2, 123L), 19.72, 1+5j,
-                 "here is a string & a <fake tag>",
+    data_list = [None, 1, 1<<123, 19.72, 1+5j,
+                 b"here is a string & a <fake tag>",
                  (1, 2, 3),
-                 ['alpha', 'beta', 'gamma', [None, 1, pow(2, 123L), 19.72,
-                                             1+5j, "& a <fake tag>"]],
-                 {'key': 'value', 1: 2},
-                 'éàù^ç'.decode('utf-8'),
-                 set(('a', 1,)),
+                 [b'alpha', b'beta', b'gamma', [None, 1, 1<<123, 19.72,
+                                                1+5j, b"& a <fake tag>"]],
+                 {b'key': b'value', 1: 2},
+                 u'éàù^ç',
+                 {b'a', 1},
                  True,
                  False,
                 ]
@@ -96,7 +93,7 @@ class TestXMLMarhsaller(unittest.TestCase):
     else:
       dumper = dump
     for item in data_list:
-      file_like_object = StringIO()
+      file_like_object = BytesIO()
       dumper(item, file_like_object)
       file_like_object.seek(0)
       self._checkXML(file_like_object)
@@ -107,8 +104,8 @@ class TestXMLMarhsaller(unittest.TestCase):
     """
     instance = _A()
     instance.subobject = _B()
-    instance.subobject.list_attribute=[None, 1, pow(2, 123L), 19.72, 1+5j,
-                                      "here is a string & a <fake tag>"]
+    instance.subobject.list_attribute=[None, 1, 1<<123, 19.72, 1+5j,
+                                       b"here is a string & a <fake tag>"]
     instance.self = instance
 
     if self.use_namespace_uri:
@@ -123,10 +120,10 @@ class TestXMLMarhsaller(unittest.TestCase):
     self.assertEquals(instance.subobject.list_attribute,
                        new_instance.subobject.list_attribute)
 
-    c_instance = _C('value1', attr2='value2')
-    c_instance.attr3 = 'value3'
-    nested_instance = _C('somevalue', 'someother')
-    nested_instance.attr3 = "stillanother"
+    c_instance = _C(b'value1', attr2=b'value2')
+    c_instance.attr3 = b'value3'
+    nested_instance = _C(b'somevalue', b'someother')
+    nested_instance.attr3 = b"stillanother"
     c_instance.nested_instance = nested_instance
     c_marshalled = dumps(c_instance)
     self._checkXML(c_marshalled)

src/xml_marshaller/xml_marshaller.py

@@ -9,14 +9,15 @@ Patched by Nicolas Delaby nicolas@nexedi.com to support namespaces
 # same name, with four functions:
 #   dump(value, file), load(file)
 #   dumps(value), loads(string)
-from types import ClassType, TypeType
+from functools import cmp_to_key
+from six import reraise
 import sys
 from xml.sax import make_parser
 from xml.sax.saxutils import escape, unescape
 from lxml.sax import ElementTreeContentHandler, saxify
 from lxml import etree
 from lxml.builder import ElementMaker
-from cStringIO import StringIO
+from io import BytesIO
 
 # Basic marshaller class, customizable by overriding it and
 # changing various attributes and methods.
@@ -24,12 +25,19 @@ from cStringIO import StringIO
 # also be a stupid hack.
 MARSHAL_PREFIX = 'marshal'
 
+try:
+  cmp
+except NameError:
+  cmp = lambda x, y: (x > y) - (x < y)
+
+@cmp_to_key
 def version_independent_cmp(a, b):
-  ta = type(a)
-  tb = type(b)
-  if ta is not tb:
-    return cmp(ta.__name__, tb.__name__)
+  a = a[0]
+  b = b[0]
+  try:
     return cmp(a, b)
+  except TypeError:
+    return cmp(repr(a), repr(b))
 
 class Marshaller(object):
 
@@ -103,7 +111,7 @@ class Marshaller(object):
   def _marshal(self, value, kw):
     t = type(value)
     i = str(id(value))
-    if kw.has_key(i):
+    if i in kw:
       return self.m_reference(value, kw)
     else:
       method_id =  'm_%s' % (type(value).__name__,)
@@ -119,7 +127,7 @@ class Marshaller(object):
 
   # Utility function, used for types that aren't implemented
   def m_unimplemented(self, value, kw):
-    raise ValueError, ("Marshalling of object %r unimplemented or not supported in this DTD" % value)
+    raise ValueError("Marshalling of object %r unimplemented or not supported in this DTD" % value)
 
   # The real entry point for marshalling, to handle properly
   # and cleanly any root tag or tags necessary for the marshalled
@@ -137,29 +145,34 @@ class Marshaller(object):
     return self.tag_reference(id='i%s' % i)
 
   def m_string(self, value, kw):
-    return self.tag_string(escape(str(value)))
+    return self.tag_string(escape(value))
 
   def m_unicode(self, value, kw):
-    return self.tag_unicode(value)
+    return self.tag_unicode(escape(value))
+
   # Since Python 2.2, the string type has a name of 'str'
   # To avoid having to rewrite all classes that implement m_string
   # we delegate m_str to m_string.
+  try:
+    unicode
+  except NameError:
+    def m_str(self, value, kw):
+      return self.m_unicode(value, kw)
+    def m_bytes(self, value, kw):
+      return self.m_string(value.decode('utf-8'), kw)
+  else:
     def m_str(self, value, kw):
       return self.m_string(value, kw)
 
   def m_int(self, value, kw):
-    return self.tag_int(str(value))
+    return (self.tag_int if -1e24 < value < 1e24 else
+            self.tag_long)(str(value))
+
+  m_long = m_int
 
   def m_float(self, value, kw):
     return self.tag_float(str(value))
 
-  def m_long(self, value, kw):
-    value = str(value)
-    if value[-1] == 'L':
-      # some Python versions append and 'L'
-      value = value[:-1]
-    return self.tag_long(value)
-
   def m_tuple(self, value, kw):
     xml_tree = self.tag_tuple()
     for elem in value:
@@ -182,11 +195,10 @@ class Marshaller(object):
     kw[str(id(value))] = i
     kw[i] = value
     xml_tree = self.tag_dictionary(id='i%s' % i)
-    item_list = value.items()
     # Sort the items to allow reproducable results across Python
     # versions
-    item_list.sort(version_independent_cmp)
-    for key, v in item_list:
+    for key, v in sorted(value.items(),
+                         key=version_independent_cmp):
       xml_tree.append(self._marshal(key, kw))
       xml_tree.append(self._marshal(v, kw))
     return xml_tree
@@ -339,8 +351,7 @@ class Unmarshaller(ElementTreeContentHandler):
     # Instantiate a new object; unmarshalling isn't thread-safe
     # because it modifies attributes on the object.
     m = self.__class__()
-    file_object = StringIO(string)
-    return m._load(file_object)
+    return m._load(BytesIO(string))
 
   # Basic unmarshalling routine; it creates a SAX XML parser,
   # registers self as the SAX handler, parses it, and returns
@@ -394,8 +405,7 @@ class Unmarshaller(ElementTreeContentHandler):
     ns_uri, local_name = ns_name
     sm, em = self.unmarshal_meth[local_name]
     if sm is not None:
-      attrib = {}
-      [attrib.update({k[1]: v}) for k, v in attrs.items()]
+      attrib = {k[1]: v for k, v in attrs.items()}
       return sm(local_name, attrib)
 
   def characters(self, data):
@@ -420,14 +430,11 @@ class Unmarshaller(ElementTreeContentHandler):
   # "empty" state.
   def um_start_root(self, name, attrs):
     if self.kw or self.data_stack:
-      raise ValueError, "root element %s found elsewhere than root" \
-            % repr(name)
+      raise ValueError("root element %r found elsewhere than root"
+            % name)
 
   def um_start_reference(self, name, attrs):
-    assert attrs.has_key('id')
-    id = attrs['id']
-    assert self.kw.has_key(id)
-    self.data_stack.append(self.kw[id])
+    self.data_stack.append(self.kw[attrs['id']])
 
   def um_start_generic(self, name, attrs):
     self.data_stack.append([])
@@ -441,7 +448,7 @@ class Unmarshaller(ElementTreeContentHandler):
   def um_end_string(self, name):
     ds = self.data_stack
     value = unescape(''.join(ds[-1]))
-    if isinstance(value, unicode):
+    if not isinstance(value, bytes):
       value = value.encode('utf-8')
     ds[-1] = value
     self.accumulating_chars = 0
@@ -449,7 +456,7 @@ class Unmarshaller(ElementTreeContentHandler):
   def um_end_unicode(self, name):
     ds = self.data_stack
     value = unescape(''.join(ds[-1]))
-    if not isinstance(value, unicode):
+    if isinstance(value, bytes):
       value = value.decode('utf-8')
     ds[-1] = value
     self.accumulating_chars = 0
@@ -463,7 +470,7 @@ class Unmarshaller(ElementTreeContentHandler):
   def um_end_long(self, name):
     ds = self.data_stack
     ds[-1] = ''.join(ds[-1])
-    ds[-1] = long(ds[-1])
+    ds[-1] = int(ds[-1])
     self.accumulating_chars = 0
 
   def um_end_float(self, name):
@@ -497,9 +504,8 @@ class Unmarshaller(ElementTreeContentHandler):
   def um_start_list(self, name, attrs):
     self.data_stack.append(LIST)
     L = []
-    if attrs.has_key('id'):
-      id = attrs['id']
-      self.kw[id] = L
+    if 'id' in attrs:
+      self.kw[attrs['id']] = L
     self.data_stack.append(L)
 
   def um_start_set(self, name, attrs):
@@ -553,9 +559,8 @@ class Unmarshaller(ElementTreeContentHandler):
   def um_start_dictionary(self, name, attrs):
     self.data_stack.append(DICT)
     d = {}
-    if attrs.has_key('id'):
-      id = attrs['id']
-      self.kw[id] = d
+    if 'id' in attrs:
+      self.kw[attrs['id']] = d
     self.data_stack.append(d)
 
   def um_end_dictionary(self, name):
@@ -575,9 +580,8 @@ class Unmarshaller(ElementTreeContentHandler):
     module = attrs['module']
     classname = attrs['class']
     value = _EmptyClass()
-    if attrs.has_key('id'):
-      id = attrs['id']
-      self.kw[id] = value
+    if 'id' in attrs:
+      self.kw[attrs['id']] = value
     self.data_stack.append(value)
     self.data_stack.append(module)
     self.data_stack.append(classname)
@@ -585,15 +589,15 @@ class Unmarshaller(ElementTreeContentHandler):
   def um_end_instance(self, name):
     value, module, classname, initargs, kw = self.data_stack[-5:]
     klass = self.find_class(module, classname)
-    if (not initargs and (isinstance(klass, (ClassType, TypeType))) and
+    if (not initargs and isinstance(klass, type) and
       not hasattr(klass, '__getinitargs__')):
       value = klass()
     else:
       try:
-        value = apply(klass, initargs)
-      except TypeError, err:
-        raise TypeError, 'in constructor for %s: %s' % (
-            klass.__name__, str(err)), sys.exc_info()[2]
+        value = klass(*initargs)
+      except TypeError as err:
+        reraise(TypeError, 'in constructor for %s: %s' % (
+            klass.__name__, err), sys.exc_info()[2])
 
     # Now set the object's attributes from the marshalled dictionary
     for k, v in kw.items():