Paul Prescod <paul@prescod.net>:
W3C DOM implementation for Python.
diff --git a/Lib/xml/dom/pulldom.py b/Lib/xml/dom/pulldom.py
new file mode 100644
index 0000000..9c85646
--- /dev/null
+++ b/Lib/xml/dom/pulldom.py
@@ -0,0 +1,267 @@
+import minidom
+import types
+import string
+import sys
+import pyexpat
+from xml.sax import ExpatParser
+
+#todo: SAX2/namespace handling
+
+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:
+ def __init__( self ):
+ self.firstEvent=[None,None]
+ self.lastEvent=self.firstEvent
+
+ def setDocumentLocator( self, locator ): pass
+
+ def startElement( self, tagName , attrs ):
+ if not hasattr( self, "curNode" ):
+ # FIXME: hack!
+ self.startDocument( )
+
+ node = self.document.createElement( tagName ) #FIXME namespaces!
+ for attr in attrs.keys():
+ node.setAttribute( attr, attrs[attr] )
+
+ parent=self.curNode
+ node.parentNode = parent
+ if parent.childNodes:
+ node.previousSibling=parent.childNodes[-1]
+ node.previousSibling.nextSibling=node
+ self.curNode = node
+ # FIXME: do I have to screen namespace attributes
+ self.lastEvent[1]=[(START_ELEMENT, node), None ]
+ self.lastEvent=self.lastEvent[1]
+ #self.events.append( (START_ELEMENT, node) )
+
+ def endElement( self, name ):
+ node = self.curNode
+ self.lastEvent[1]=[(END_ELEMENT, node), None ]
+ self.lastEvent=self.lastEvent[1]
+ #self.events.append( (END_ELEMENT, node ))
+ self.curNode = node.parentNode
+
+ def comment( self, s):
+ node = self.document.createComment ( s )
+ parent=self.curNode
+ node.parentNode=parent
+ if parent.childNodes:
+ node.previousSibling=parent.childNodes[-1]
+ node.previousSibling.nextSibling=node
+ self.lastEvent[1]=[(COMMENT, node), None ]
+ self.lastEvent=self.lastEvent[1]
+ #self.events.append( (COMMENT, node ))
+
+ def processingInstruction( self, target, data ):
+ node = self.document.createProcessingInstruction( target, data )
+ #self.appendChild( node )
+
+ parent=self.curNode
+ node.parentNode=parent
+ if parent.childNodes:
+ node.previousSibling=parent.childNodes[-1]
+ node.previousSibling.nextSibling=node
+ self.lastEvent[1]=[(PROCESSING_INSTRUCTION, node), None ]
+ self.lastEvent=self.lastEvent[1]
+ #self.events.append( (PROCESSING_INSTRUCTION, node) )
+
+ def ignorableWhitespace( self, chars ):
+ node = self.document.createTextNode( chars[start:start+length] )
+ parent=self.curNode
+ node.parentNode=parent
+ if parent.childNodes:
+ node.previousSibling=parent.childNodes[-1]
+ node.previousSibling.nextSibling=node
+ self.lastEvent[1]=[(IGNORABLE_WHITESPACE, node), None ]
+ self.lastEvent=self.lastEvent[1]
+ #self.events.append( (IGNORABLE_WHITESPACE, node))
+
+ def characters( self, chars ):
+ node = self.document.createTextNode( chars )
+ node.parentNode=self.curNode
+ self.lastEvent[1]=[(CHARACTERS, node), None ]
+ self.lastEvent=self.lastEvent[1]
+
+ def startDocument( self ):
+ node = self.curNode = self.document = minidom.Document()
+ node.parentNode=None
+ self.lastEvent[1]=[(START_DOCUMENT, node), None ]
+ self.lastEvent=self.lastEvent[1]
+ #self.events.append( (START_DOCUMENT, node) )
+
+ def endDocument( self ):
+ assert( not self.curNode.parentNode )
+ for node in self.curNode.childNodes:
+ if node.nodeType==node.ELEMENT_NODE:
+ self.document.documentElement = node
+ #if not self.document.documentElement:
+ # raise Error, "No document element"
+
+ self.lastEvent[1]=[(END_DOCUMENT, node), None ]
+ #self.events.append( (END_DOCUMENT, self.curNode) )
+
+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()
+ 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()
+ while event:
+ token,cur_node=event
+ if cur_node is node: return
+
+ if token !=END_ELEMENT:
+ cur_node.parentNode.childNodes.append( cur_node )
+ event=self.getEvent()
+ if node.nodeType==minidom.Node.DOCUMENT_NODE:
+ for child in node.childNodes:
+ if child.nodeType==minidom.Node.ELEMENT_NODE:
+ node.documentElement=child
+
+ 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:
+ #FIXME: why doesn't Expat close work?
+ #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
+
+# FIXME: sax2
+#def _getParser( ):
+ # from xml.sax.saxexts import make_parser
+ # expat doesn't report errors properly! Figure it out
+ # return make_parser()
+ # return make_parser("xml.sax.drivers.drv_xmllib")
+
+
+
+def _getParser():
+ return ExpatParser()
+
+default_bufsize=(2**14)-20
+# FIXME: move into sax package for common usage
+def parse( stream_or_string, parser=None, bufsize=default_bufsize ):
+ if type( stream_or_string ) == type( "" ):
+ stream=open( stream_or_string )
+ else:
+ stream=stream_or_string
+ if not parser:
+ parser=_getParser()
+ return DOMEventStream( stream, parser, bufsize )
+
+def parseString( string, parser=None ):
+ try:
+ import cStringIO
+ stringio=cStringIO.StringIO
+ except ImportError:
+ import StringIO
+ stringio=StringIO.StringIO
+
+ bufsize=len( string )
+ stringio( string )
+ parser=_getParser()
+ return DOMEventStream( buf, parser, bufsize )
+
+#FIXME: Use Lars' instead!!!
+class SAX_expat:
+ "SAX driver for the Pyexpat C module."
+
+ def __init__(self):
+ self.parser=pyexpat.ParserCreate()
+ self.started=0
+
+ def setDocumentHandler( self, handler ):
+ self.parser.StartElementHandler = handler.startElement
+ self.parser.EndElementHandler = handler.endElement
+ self.parser.CharacterDataHandler = handler.datachars
+ self.parser.ProcessingInstructionHandler = handler.processingInstruction
+ self.doc_handler=handler
+
+ def setErrorHandler( self, handler ):
+ self.err_handler=handler
+
+ # --- Locator methods. Only usable after errors.
+
+ def getLineNumber(self):
+ return self.parser.ErrorLineNumber
+
+ def getColumnNumber(self):
+ return self.parser.ErrorColumnNumber
+
+ # --- Internal
+
+ def __report_error(self):
+ msg=pyexpat.ErrorString(self.parser.ErrorCode)
+ self.err_handler.fatalError(msg)
+
+ # --- EXPERIMENTAL PYTHON SAX EXTENSIONS
+
+ def get_parser_name(self):
+ return "pyexpat"
+
+ def get_parser_version(self):
+ return "Unknown"
+
+ def get_driver_version(self):
+ return version
+
+ def is_validating(self):
+ return 0
+
+ def is_dtd_reading(self):
+ return 0
+
+ def reset(self):
+ self.parser=pyexpat.ParserCreate()
+ self.parser.StartElementHandler = self.startElement
+ self.parser.EndElementHandler = self.endElement
+ self.parser.CharacterDataHandler = self.characters
+ self.parser.ProcessingInstructionHandler = self.processingInstruction
+
+ def feed(self,data):
+ if not self.started:
+ self.doc_handler.startDocument()
+ self.started=1
+ if not self.parser.Parse(data):
+ self.__report_error()
+
+ def close(self):
+ if not self.parser.Parse("",1):
+ self.__report_error()
+ self.doc_handler.endDocument()
+ self.parser = None