1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
|
import xml.sax
import xml.sax.handler
import types
try:
_StringTypes = [types.StringType, types.UnicodeType]
except AttributeError:
_StringTypes = [types.StringType]
START_ELEMENT = "START_ELEMENT"
END_ELEMENT = "END_ELEMENT"
COMMENT = "COMMENT"
START_DOCUMENT = "START_DOCUMENT"
END_DOCUMENT = "END_DOCUMENT"
PROCESSING_INSTRUCTION = "PROCESSING_INSTRUCTION"
IGNORABLE_WHITESPACE = "IGNORABLE_WHITESPACE"
CHARACTERS = "CHARACTERS"
class PullDOM(xml.sax.ContentHandler):
_locator = None
document = None
def __init__(self, documentFactory=None):
self.documentFactory = documentFactory
self.firstEvent = [None, None]
self.lastEvent = self.firstEvent
self.elementStack = []
self.push = self.elementStack.append
try:
self.pop = self.elementStack.pop
except AttributeError:
# use class' pop instead
pass
self._ns_contexts = [{}] # contains uri -> prefix dicts
self._current_context = self._ns_contexts[-1]
self.pending_events = []
def pop(self):
result = self.elementStack[-1]
del self.elementStack[-1]
return result
def setDocumentLocator(self, locator):
self._locator = locator
def startPrefixMapping(self, prefix, uri):
self._ns_contexts.append(self._current_context.copy())
self._current_context[uri] = prefix or ''
def endPrefixMapping(self, prefix):
self._current_context = self._ns_contexts.pop()
def startElementNS(self, name, tagName , attrs):
uri, localname = name
if uri:
# When using namespaces, the reader may or may not
# provide us with the original name. If not, create
# *a* valid tagName from the current context.
if tagName is None:
prefix = self._current_context[uri]
if prefix:
tagName = prefix + ":" + localname
else:
tagName = localname
if self.document:
node = self.document.createElementNS(uri, tagName)
else:
node = self.buildDocument(uri, tagName)
else:
# When the tagname is not prefixed, it just appears as
# localname
if self.document:
node = self.document.createElement(localname)
else:
node = self.buildDocument(None, localname)
for aname,value in attrs.items():
a_uri, a_localname = aname
if a_uri:
prefix = self._current_context[a_uri]
if prefix:
qname = prefix + ":" + a_localname
else:
qname = a_localname
attr = self.document.createAttributeNS(a_uri, qname)
node.setAttributeNodeNS(attr)
else:
attr = self.document.createAttribute(a_localname)
node.setAttributeNode(attr)
attr.value = value
self.lastEvent[1] = [(START_ELEMENT, node), None]
self.lastEvent = self.lastEvent[1]
self.push(node)
def endElementNS(self, name, tagName):
self.lastEvent[1] = [(END_ELEMENT, self.pop()), None]
self.lastEvent = self.lastEvent[1]
def startElement(self, name, attrs):
if self.document:
node = self.document.createElement(name)
else:
node = self.buildDocument(None, name)
for aname,value in attrs.items():
attr = self.document.createAttribute(aname)
attr.value = value
node.setAttributeNode(attr)
self.lastEvent[1] = [(START_ELEMENT, node), None]
self.lastEvent = self.lastEvent[1]
self.push(node)
def endElement(self, name):
self.lastEvent[1] = [(END_ELEMENT, self.pop()), None]
self.lastEvent = self.lastEvent[1]
def comment(self, s):
if self.document:
node = self.document.createComment(s)
self.lastEvent[1] = [(COMMENT, node), None]
self.lastEvent = self.lastEvent[1]
else:
event = [(COMMENT, s), None]
self.pending_events.append(event)
def processingInstruction(self, target, data):
if self.document:
node = self.document.createProcessingInstruction(target, data)
self.lastEvent[1] = [(PROCESSING_INSTRUCTION, node), None]
self.lastEvent = self.lastEvent[1]
else:
event = [(PROCESSING_INSTRUCTION, target, data), None]
self.pending_events.append(event)
def ignorableWhitespace(self, chars):
node = self.document.createTextNode(chars)
self.lastEvent[1] = [(IGNORABLE_WHITESPACE, node), None]
self.lastEvent = self.lastEvent[1]
def characters(self, chars):
node = self.document.createTextNode(chars)
self.lastEvent[1] = [(CHARACTERS, node), None]
self.lastEvent = self.lastEvent[1]
def startDocument(self):
if self.documentFactory is None:
import xml.dom.minidom
self.documentFactory = xml.dom.minidom.Document.implementation
def buildDocument(self, uri, tagname):
# Can't do that in startDocument, since we need the tagname
# XXX: obtain DocumentType
node = self.documentFactory.createDocument(uri, tagname, None)
self.document = node
self.lastEvent[1] = [(START_DOCUMENT, node), None]
self.lastEvent = self.lastEvent[1]
self.push(node)
# Put everything we have seen so far into the document
for e in self.pending_events:
if e[0][0] == PROCESSING_INSTRUCTION:
_,target,data = e[0]
n = self.document.createProcessingInstruction(target, data)
e[0] = (PROCESSING_INSTRUCTION, n)
elif e[0][0] == COMMENT:
n = self.document.createComment(e[0][1])
e[0] = (COMMENT, n)
else:
raise AssertionError("Unknown pending event ",e[0][0])
self.lastEvent[1] = e
self.lastEvent = e
self.pending_events = None
return node.firstChild
def endDocument(self):
self.lastEvent[1] = [(END_DOCUMENT, self.document), None]
self.pop()
def clear(self):
"clear(): Explicitly release parsing structures"
self.document = None
class ErrorHandler:
def warning(self, exception):
print exception
def error(self, exception):
raise exception
def fatalError(self, exception):
raise exception
class DOMEventStream:
def __init__(self, stream, parser, bufsize):
self.stream = stream
self.parser = parser
self.bufsize = bufsize
self.reset()
def reset(self):
self.pulldom = PullDOM()
# This content handler relies on namespace support
self.parser.setFeature(xml.sax.handler.feature_namespaces, 1)
self.parser.setContentHandler(self.pulldom)
def __getitem__(self, pos):
rc = self.getEvent()
if rc:
return rc
raise IndexError
def expandNode(self, node):
event = self.getEvent()
parents = [node]
while event:
token, cur_node = event
if cur_node is node:
return
if token != END_ELEMENT:
parents[-1].appendChild(cur_node)
if token == START_ELEMENT:
parents.append(cur_node)
elif token == END_ELEMENT:
del parents[-1]
event = self.getEvent()
def getEvent(self):
if not self.pulldom.firstEvent[1]:
self.pulldom.lastEvent = self.pulldom.firstEvent
while not self.pulldom.firstEvent[1]:
buf = self.stream.read(self.bufsize)
if not buf:
self.parser.close()
return None
self.parser.feed(buf)
rc = self.pulldom.firstEvent[1][0]
self.pulldom.firstEvent[1] = self.pulldom.firstEvent[1][1]
return rc
def clear(self):
"clear(): Explicitly release parsing objects"
self.pulldom.clear()
del self.pulldom
self.parser = None
self.stream = None
class SAX2DOM(PullDOM):
def startElementNS(self, name, tagName , attrs):
PullDOM.startElementNS(self, name, tagName, attrs)
curNode = self.elementStack[-1]
parentNode = self.elementStack[-2]
parentNode.appendChild(curNode)
def startElement(self, name, attrs):
PullDOM.startElement(self, name, attrs)
curNode = self.elementStack[-1]
parentNode = self.elementStack[-2]
parentNode.appendChild(curNode)
def processingInstruction(self, target, data):
PullDOM.processingInstruction(self, target, data)
node = self.lastEvent[0][1]
parentNode = self.elementStack[-1]
parentNode.appendChild(node)
def ignorableWhitespace(self, chars):
PullDOM.ignorableWhitespace(self, chars)
node = self.lastEvent[0][1]
parentNode = self.elementStack[-1]
parentNode.appendChild(node)
def characters(self, chars):
PullDOM.characters(self, chars)
node = self.lastEvent[0][1]
parentNode = self.elementStack[-1]
parentNode.appendChild(node)
default_bufsize = (2 ** 14) - 20
def parse(stream_or_string, parser=None, bufsize=None):
if bufsize is None:
bufsize = default_bufsize
if type(stream_or_string) in _StringTypes:
stream = open(stream_or_string)
else:
stream = stream_or_string
if not parser:
parser = xml.sax.make_parser()
return DOMEventStream(stream, parser, bufsize)
def parseString(string, parser=None):
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
bufsize = len(string)
buf = StringIO(string)
if not parser:
parser = xml.sax.make_parser()
return DOMEventStream(buf, parser, bufsize)
|
