use class pop instead retrieve xml namespace declaration attributes 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 when the tagname is not prefixed it just appears as localname can t do that in startdocument since we need the tagname xxx obtain documenttype put everything we have seen so far into the document this content handler relies on namespace support use incrementalparser interface so we get the desired pull effect fallback replacement for getevent using the standard sax2 interface which means we slurp the sax events into memory no performance gain but we are compatible to all sax parsers fallback replacement for getevent that emits the events that slurp read previously clear explicitly release parsing objects self pulldom clear del self pulldom self parser none self stream none class sax2dompulldom def startelementnsself name tagname attrs pulldom startelementnsself name tagname attrs curnode self elementstack1 parentnode self elementstack2 parentnode appendchildcurnode def startelementself name attrs pulldom startelementself name attrs curnode self elementstack1 parentnode self elementstack2 parentnode appendchildcurnode def processinginstructionself target data pulldom processinginstructionself target data node self lastevent01 parentnode self elementstack1 parentnode appendchildnode def ignorablewhitespaceself chars pulldom ignorablewhitespaceself chars node self lastevent01 parentnode self elementstack1 parentnode appendchildnode def charactersself chars pulldom charactersself chars node self lastevent01 parentnode self elementstack1 parentnode appendchildnode defaultbufsize 2 14 20 def parsestreamorstring parsernone bufsizenone if bufsize is none bufsize defaultbufsize if isinstancestreamorstring str stream openstreamorstring rb else stream streamorstring if not parser parser xml sax makeparser return domeventstreamstream parser bufsize def parsestringstring parsernone from io import stringio bufsize lenstring buf stringiostring if not parser parser xml sax makeparser return domeventstreambuf parser bufsize use class pop instead contains uri prefix dicts retrieve xml namespace declaration attributes 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 when the tagname is not prefixed it just appears as localname can t do that in startdocument since we need the tagname xxx obtain documenttype put everything we have seen so far into the document this content handler relies on namespace support use incrementalparser interface so we get the desired pull effect fallback replacement for getevent using the standard sax2 interface which means we slurp the sax events into memory no performance gain but we are compatible to all sax parsers fallback replacement for getevent that emits the events that _slurp read previously clear explicitly release parsing objects
import xml.sax
import xml.sax.handler

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):
        from xml.dom import XML_NAMESPACE
        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:
            
            pass
        self._ns_contexts = [{XML_NAMESPACE:'xml'}] 
        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):
        if not hasattr(self, '_xmlns_attrs'):
            self._xmlns_attrs = []
        self._xmlns_attrs.append((prefix or 'xmlns', uri))
        self._ns_contexts.append(self._current_context.copy())
        self._current_context[uri] = prefix or None

    def endPrefixMapping(self, prefix):
        self._current_context = self._ns_contexts.pop()

    def startElementNS(self, name, tagName , attrs):
        
        xmlns_uri = 'http://www.w3.org/2000/xmlns/'
        xmlns_attrs = getattr(self, '_xmlns_attrs', None)
        if xmlns_attrs is not None:
            for aname, value in xmlns_attrs:
                attrs._attrs[(xmlns_uri, aname)] = value
            self._xmlns_attrs = []
        uri, localname = name
        if uri:
            
            
            
            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:
            
            
            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 == xmlns_uri:
                if a_localname == 'xmlns':
                    qname = a_localname
                else:
                    qname = 'xmlns:' + a_localname
                attr = self.document.createAttributeNS(a_uri, qname)
                node.setAttributeNodeNS(attr)
            elif 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):
        
        
        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)
        
        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
        if not hasattr(self.parser, 'feed'):
            self.getEvent = self._slurp
        self.reset()

    def reset(self):
        self.pulldom = PullDOM()
        
        self.parser.setFeature(xml.sax.handler.feature_namespaces, 1)
        self.parser.setContentHandler(self.pulldom)

    def __next__(self):
        rc = self.getEvent()
        if rc:
            return rc
        raise StopIteration

    def __iter__(self):
        return self

    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 _slurp(self):
        
        self.parser.parse(self.stream)
        self.getEvent = self._emit
        return self._emit()

    def _emit(self):
        
        rc = self.pulldom.firstEvent[1][0]
        self.pulldom.firstEvent[1] = self.pulldom.firstEvent[1][1]
        return rc

    def clear(self):
        
        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 isinstance(stream_or_string, str):
        stream = open(stream_or_string, 'rb')
    else:
        stream = stream_or_string
    if not parser:
        parser = xml.sax.make_parser()
    return DOMEventStream(stream, parser, bufsize)

def parseString(string, parser=None):
    from io import StringIO

    bufsize = len(string)
    buf = StringIO(string)
    if not parser:
        parser = xml.sax.make_parser()
    return DOMEventStream(buf, parser, bufsize)