1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 """This module contains support for a DOM tree representation from an XML
16 document using a SAX parser.
17
18 This functionality exists because we need a DOM interface to generate the
19 binding classses, but the Python C{xml.dom.minidom} package does not support
20 location information. The SAX interface does, so we have a SAX content
21 handler which converts the SAX events into a DOM tree.
22
23 This is not a general-purpose DOM capability; only a small subset of the DOM
24 interface is supported, and only for storing the XML information, not for
25 converting it back into document format.
26 """
27
28 import xml.dom
29 import saxutils
30 import StringIO
31 import pyxb.namespace
32
34 """Utility function to print a DOM tree."""
35
36 pfx = ' ' * depth
37 if (xml.dom.Node.ELEMENT_NODE == n.nodeType):
38 print '%sElement[%d] %s %s with %d children' % (pfx, n._indexInParent(), n, pyxb.namespace.ExpandedName(n.name), len(n.childNodes))
39 ins = pyxb.namespace.resolution.NamespaceContext.GetNodeContext(n).inScopeNamespaces()
40 print '%s%s' % (pfx, ' ; '.join([ '%s=%s' % (_k, _v.uri()) for (_k, _v) in ins.items()]))
41 for (k, v) in n.attributes.items():
42 print '%s %s=%s' % (pfx, pyxb.namespace.ExpandedName(k), v)
43 for cn in n.childNodes:
44 _DumpDOM(cn, depth+1)
45 elif (xml.dom.Node.TEXT_NODE == n.nodeType):
46
47 pass
48 elif (xml.dom.Node.DOCUMENT_NODE == n.nodeType):
49 print 'Document node'
50 _DumpDOM(n.firstChild, depth)
51 else:
52 print 'UNRECOGNIZED %s' % (n.nodeType,)
53
55 """SAX handler class that transforms events into a DOM tree."""
56
58 """The document that is the root of the generated tree."""
59 return self.__document
60 __document = None
61
65
71
72
80
82 this_state = super(_DOMSAXHandler, self).endElementNS(name, qname)
83 ns_ctx = this_state.namespaceContext()
84 element = Element(namespace_context=ns_ctx, expanded_name=this_state.expandedName(), attributes=this_state.__attributes, location=this_state.location())
85 for ( content, element_use, maybe_element ) in this_state.content():
86 if isinstance(content, Node):
87 element.appendChild(content)
88 else:
89 element.appendChild(Text(content, namespace_context=ns_ctx))
90 parent_state = this_state.parentState()
91 parent_state.addElementContent(element, None)
92
93
95 """Parse a stream containing an XML document and return the DOM tree
96 representing its contents.
97
98 Keywords not described here are passed to L{saxutils.make_parser}.
99
100 @param stream: An object presenting the standard file C{read} interface
101 from which the document can be read.
102
103 @keyword content_handler_constructor: Input is overridden to assign this a
104 value of L{_DOMSAXHandler}.
105
106 @rtype: C{xml.dom.Document}
107 """
108
109 kw['content_handler_constructor'] = _DOMSAXHandler
110 saxer = saxutils.make_parser(**kw)
111 handler = saxer.getContentHandler()
112 saxer.parse(stream)
113 return handler.document()
114
116 """Parse a string holding an XML document and return the corresponding DOM
117 tree."""
118
119 return parse(StringIO.StringIO(text), **kw)
120
121 -class Node (xml.dom.Node, pyxb.utils.utility.Locatable_mixin):
191
193 """Add the documentElement interface."""
196
197 documentElement = Node.firstChild
198
200 """Add the nodeName and nodeValue interface."""
203 nodeName = Node.name
204 nodeValue = Node.value
205
207 """Implement that portion of NamedNodeMap required to satisfy PyXB's
208 needs."""
209 __members = None
210
214
215 length = property(lambda _s: len(_s.__members))
216 - def item (self, index):
218
223
225 for attr in self.__members:
226 if attr.name == name:
227 return attr
228 return None
229
235
237 """Abstract base for anything holding text data."""
238 data = Node.value
239
240 -class Text (_CharacterData):
241 - def __init__ (self, text, **kw):
242 super(Text, self).__init__(value=text, node_type=xml.dom.Node.TEXT_NODE, **kw)
243
247
248 if '__main__' == __name__:
249 import sys
250 xml_file = '/home/pab/pyxb/dev/examples/tmsxtvd/tmsdatadirect_sample.xml'
251 if 1 < len(sys.argv):
252 xml_file = sys.argv[1]
253
254 doc = parse(file(xml_file))
255
256
257
258
259