root / trunk / twisted / web / microdom.py

# -*- test-case-name: twisted.web.test.test_xml -*-
# Copyright (c) 2001-2008 Twisted Matrix Laboratories.
# See LICENSE for details.

"""
Micro Document Object Model: a partial DOM implementation with SUX.

This is an implementation of what we consider to be the useful subset of the
DOM.  The chief advantage of this library is that, not being burdened with
standards compliance, it can remain very stable between versions.  We can also
implement utility 'pythonic' ways to access and mutate the XML tree.

Since this has not subjected to a serious trial by fire, it is not recommended
to use this outside of Twisted applications.  However, it seems to work just
fine for the documentation generator, which parses a fairly representative
sample of XML.

Microdom mainly focuses on working with HTML and XHTML.
"""

# System Imports
import re
from cStringIO import StringIO

# create NodeList class
from types import ListType as NodeList
from types import StringTypes, UnicodeType

# Twisted Imports
from twisted.web.sux import XMLParser, ParseError
from twisted.python.util import InsensitiveDict


def getElementsByTagName(iNode, name):
    """
    Return a list of all child elements of C{iNode} with a name matching
    C{name}.

    Note that this implementation does not conform to the DOM Level 1 Core
    specification because it may return C{iNode}.

    @param iNode: An element at which to begin searching.  If C{iNode} has a
        name matching C{name}, it will be included in the result.

    @param name: A C{str} giving the name of the elements to return.

    @return: A C{list} of direct or indirect child elements of C{iNode} with
        the name C{name}.  This may include C{iNode}.
    """
    matches = []
    matches_append = matches.append # faster lookup. don't do this at home
    slice = [iNode]
    while len(slice)>0:
        c = slice.pop(0)
        if c.nodeName == name:
            matches_append(c)
        slice[:0] = c.childNodes
    return matches



def getElementsByTagNameNoCase(iNode, name):
    name = name.lower()
    matches = []
    matches_append = matches.append
    slice=[iNode]
    while len(slice)>0:
        c = slice.pop(0)
        if c.nodeName.lower() == name:
            matches_append(c)
        slice[:0] = c.childNodes
    return matches

# order is important
HTML_ESCAPE_CHARS = (('&', '&'), # don't add any entities before this one
                    ('<', '&lt;'),
                    ('>', '&gt;'),
                    ('"', '&quot;'))
REV_HTML_ESCAPE_CHARS = list(HTML_ESCAPE_CHARS)
REV_HTML_ESCAPE_CHARS.reverse()

XML_ESCAPE_CHARS = HTML_ESCAPE_CHARS + (("'", '&apos;'),)
REV_XML_ESCAPE_CHARS = list(XML_ESCAPE_CHARS)
REV_XML_ESCAPE_CHARS.reverse()

def unescape(text, chars=REV_HTML_ESCAPE_CHARS):
    "Perform the exact opposite of 'escape'."
    for s, h in chars:
        text = text.replace(h, s)
    return text

def escape(text, chars=HTML_ESCAPE_CHARS):
    "Escape a few XML special chars with XML entities."
    for s, h in chars:
        text = text.replace(s, h)
    return text


class MismatchedTags(Exception):

    def __init__(self, filename, expect, got, endLine, endCol, begLine, begCol):
       (self.filename, self.expect, self.got, self.begLine, self.begCol, self.endLine,
        self.endCol) = filename, expect, got, begLine, begCol, endLine, endCol

    def __str__(self):
        return ("expected </%s>, got </%s> line: %s col: %s, began line: %s col: %s"
                % (self.expect, self.got, self.endLine, self.endCol, self.begLine,
                   self.begCol))


class Node(object):
    nodeName = "Node"

    def __init__(self, parentNode=None):
        self.parentNode = parentNode
        self.childNodes = []

    def isEqualToNode(self, other):
        """
        Compare this node to C{other}.  If the nodes have the same number of
        children and corresponding children are equal to each other, return
        C{True}, otherwise return C{False}.

        @type other: L{Node}
        @rtype: C{bool}
        """
        if len(self.childNodes) != len(other.childNodes):
            return False
        for a, b in zip(self.childNodes, other.childNodes):
            if not a.isEqualToNode(b):
                return False
        return True

    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        raise NotImplementedError()

    def toxml(self, indent='', addindent='', newl='', strip=0, nsprefixes={},
              namespace=''):
        s = StringIO()
        self.writexml(s, indent, addindent, newl, strip, nsprefixes, namespace)
        rv = s.getvalue()
        return rv

    def writeprettyxml(self, stream, indent='', addindent=' ', newl='\n', strip=0):
        return self.writexml(stream, indent, addindent, newl, strip)

    def toprettyxml(self, indent='', addindent=' ', newl='\n', strip=0):
        return self.toxml(indent, addindent, newl, strip)

    def cloneNode(self, deep=0, parent=None):
        raise NotImplementedError()

    def hasChildNodes(self):
        if self.childNodes:
            return 1
        else:
            return 0


    def appendChild(self, child):
        """
        Make the given L{Node} the last child of this node.

        @param child: The L{Node} which will become a child of this node.

        @raise TypeError: If C{child} is not a C{Node} instance.
        """
        if not isinstance(child, Node):
            raise TypeError("expected Node instance")
        self.childNodes.append(child)
        child.parentNode = self


    def insertBefore(self, new, ref):
        """
        Make the given L{Node} C{new} a child of this node which comes before
        the L{Node} C{ref}.

        @param new: A L{Node} which will become a child of this node.

        @param ref: A L{Node} which is already a child of this node which
            C{new} will be inserted before.

        @raise TypeError: If C{new} or C{ref} is not a C{Node} instance.

        @return: C{new}
        """
        if not isinstance(new, Node) or not isinstance(ref, Node):
            raise TypeError("expected Node instance")
        i = self.childNodes.index(ref)
        new.parentNode = self
        self.childNodes.insert(i, new)
        return new


    def removeChild(self, child):
        """
        Remove the given L{Node} from this node's children.

        @param child: A L{Node} which is a child of this node which will no
            longer be a child of this node after this method is called.

        @raise TypeError: If C{child} is not a C{Node} instance.

        @return: C{child}
        """
        if not isinstance(child, Node):
            raise TypeError("expected Node instance")
        if child in self.childNodes:
            self.childNodes.remove(child)
            child.parentNode = None
        return child

    def replaceChild(self, newChild, oldChild):
        """
        Replace a L{Node} which is already a child of this node with a
        different node.

        @param newChild: A L{Node} which will be made a child of this node.

        @param oldChild: A L{Node} which is a child of this node which will
            give up its position to C{newChild}.

        @raise TypeError: If C{newChild} or C{oldChild} is not a C{Node}
            instance.

        @raise ValueError: If C{oldChild} is not a child of this C{Node}.
        """
        if not isinstance(newChild, Node) or not isinstance(oldChild, Node):
            raise TypeError("expected Node instance")
        if oldChild.parentNode is not self:
            raise ValueError("oldChild is not a child of this node")
        self.childNodes[self.childNodes.index(oldChild)] = newChild
        oldChild.parentNode = None
        newChild.parentNode = self


    def lastChild(self):
        return self.childNodes[-1]


    def firstChild(self):
        if len(self.childNodes):
            return self.childNodes[0]
        return None

    #def get_ownerDocument(self):
    #   """This doesn't really get the owner document; microdom nodes
    #   don't even have one necessarily.  This gets the root node,
    #   which is usually what you really meant.
    #   *NOT DOM COMPLIANT.*
    #   """
    #   node=self
    #   while (node.parentNode): node=node.parentNode
    #   return node
    #ownerDocument=node.get_ownerDocument()
    # leaving commented for discussion; see also domhelpers.getParents(node)

class Document(Node):

    def __init__(self, documentElement=None):
        Node.__init__(self)
        if documentElement:
            self.appendChild(documentElement)

    def cloneNode(self, deep=0, parent=None):
        d = Document()
        d.doctype = self.doctype
        if deep:
            newEl = self.documentElement.cloneNode(1, self)
        else:
            newEl = self.documentElement
        d.appendChild(newEl)
        return d

    doctype = None

    def isEqualToDocument(self, n):
        return (self.doctype == n.doctype) and Node.isEqualToNode(self, n)
    isEqualToNode = isEqualToDocument

    def get_documentElement(self):
        return self.childNodes[0]
    documentElement=property(get_documentElement)

    def appendChild(self, child):
        """
        Make the given L{Node} the I{document element} of this L{Document}.

        @param child: The L{Node} to make into this L{Document}'s document
            element.

        @raise ValueError: If this document already has a document element.
        """
        if self.childNodes:
            raise ValueError("Only one element per document.")
        Node.appendChild(self, child)

    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        stream.write('<?xml version="1.0"?>' + newl)
        if self.doctype:
            stream.write("<!DOCTYPE "+self.doctype+">" + newl)
        self.documentElement.writexml(stream, indent, addindent, newl, strip,
                                      nsprefixes, namespace)

    # of dubious utility (?)
    def createElement(self, name, **kw):
        return Element(name, **kw)

    def createTextNode(self, text):
        return Text(text)

    def createComment(self, text):
        return Comment(text)

    def getElementsByTagName(self, name):
        if self.documentElement.caseInsensitive:
            return getElementsByTagNameNoCase(self, name)
        return getElementsByTagName(self, name)

    def getElementById(self, id):
        childNodes = self.childNodes[:]
        while childNodes:
            node = childNodes.pop(0)
            if node.childNodes:
                childNodes.extend(node.childNodes)
            if hasattr(node, 'getAttribute') and node.getAttribute("id") == id:
                return node


class EntityReference(Node):

    def __init__(self, eref, parentNode=None):
        Node.__init__(self, parentNode)
        self.eref = eref
        self.nodeValue = self.data = "&" + eref + ";"

    def isEqualToEntityReference(self, n):
        if not isinstance(n, EntityReference):
            return 0
        return (self.eref == n.eref) and (self.nodeValue == n.nodeValue)
    isEqualToNode = isEqualToEntityReference

    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        stream.write(self.nodeValue)

    def cloneNode(self, deep=0, parent=None):
        return EntityReference(self.eref, parent)


class CharacterData(Node):

    def __init__(self, data, parentNode=None):
        Node.__init__(self, parentNode)
        self.value = self.data = self.nodeValue = data

    def isEqualToCharacterData(self, n):
        return self.value == n.value
    isEqualToNode = isEqualToCharacterData


class Comment(CharacterData):
    """A comment node."""

    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        val=self.data
        if isinstance(val, UnicodeType):
            val=val.encode('utf8')
        stream.write("<!--%s-->" % val)

    def cloneNode(self, deep=0, parent=None):
        return Comment(self.nodeValue, parent)


class Text(CharacterData):

    def __init__(self, data, parentNode=None, raw=0):
        CharacterData.__init__(self, data, parentNode)
        self.raw = raw


    def isEqualToNode(self, other):
        """
        Compare this text to C{text}.  If the underlying values and the C{raw}
        flag are the same, return C{True}, otherwise return C{False}.
        """
        return (
            CharacterData.isEqualToNode(self, other) and
            self.raw == other.raw)


    def cloneNode(self, deep=0, parent=None):
        return Text(self.nodeValue, parent, self.raw)

    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        if self.raw:
            val = self.nodeValue
            if not isinstance(val, StringTypes):
                val = str(self.nodeValue)
        else:
            v = self.nodeValue
            if not isinstance(v, StringTypes):
                v = str(v)
            if strip:
                v = ' '.join(v.split())
            val = escape(v)
        if isinstance(val, UnicodeType):
            val = val.encode('utf8')
        stream.write(val)

    def __repr__(self):
        return "Text(%s" % repr(self.nodeValue) + ')'


class CDATASection(CharacterData):
    def cloneNode(self, deep=0, parent=None):
        return CDATASection(self.nodeValue, parent)

    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        stream.write("<![CDATA[")
        stream.write(self.nodeValue)
        stream.write("]]>")

def _genprefix():
    i = 0
    while True:
        yield  'p' + str(i)
        i = i + 1
genprefix = _genprefix().next

class _Attr(CharacterData):
    "Support class for getAttributeNode."

class Element(Node):

    preserveCase = 0
    caseInsensitive = 1
    nsprefixes = None

    def __init__(self, tagName, attributes=None, parentNode=None,
                 filename=None, markpos=None,
                 caseInsensitive=1, preserveCase=0,
                 namespace=None):
        Node.__init__(self, parentNode)
        self.preserveCase = preserveCase or not caseInsensitive
        self.caseInsensitive = caseInsensitive
        if not preserveCase:
            tagName = tagName.lower()
        if attributes is None:
            self.attributes = {}
        else:
            self.attributes = attributes
            for k, v in self.attributes.items():
                self.attributes[k] = unescape(v)

        if caseInsensitive:
            self.attributes = InsensitiveDict(self.attributes,
                                              preserve=preserveCase)

        self.endTagName = self.nodeName = self.tagName = tagName
        self._filename = filename
        self._markpos = markpos
        self.namespace = namespace

    def addPrefixes(self, pfxs):
        if self.nsprefixes is None:
            self.nsprefixes = pfxs
        else:
            self.nsprefixes.update(pfxs)

    def endTag(self, endTagName):
        if not self.preserveCase:
            endTagName = endTagName.lower()
        self.endTagName = endTagName

    def isEqualToElement(self, n):
        if self.caseInsensitive:
            return ((self.attributes == n.attributes)
                    and (self.nodeName.lower() == n.nodeName.lower()))
        return (self.attributes == n.attributes) and (self.nodeName == n.nodeName)


    def isEqualToNode(self, other):
        """
        Compare this element to C{other}.  If the C{nodeName}, C{namespace},
        C{attributes}, and C{childNodes} are all the same, return C{True},
        otherwise return C{False}.
        """
        return (
            self.nodeName.lower() == other.nodeName.lower() and
            self.namespace == other.namespace and
            self.attributes == other.attributes and
            Node.isEqualToNode(self, other))


    def cloneNode(self, deep=0, parent=None):
        clone = Element(
            self.tagName, parentNode=parent, namespace=self.namespace,
            preserveCase=self.preserveCase, caseInsensitive=self.caseInsensitive)
        clone.attributes.update(self.attributes)
        if deep:
            clone.childNodes = [child.cloneNode(1, clone) for child in self.childNodes]
        else:
            clone.childNodes = []
        return clone

    def getElementsByTagName(self, name):
        if self.caseInsensitive:
            return getElementsByTagNameNoCase(self, name)
        return getElementsByTagName(self, name)

    def hasAttributes(self):
        return 1

    def getAttribute(self, name, default=None):
        return self.attributes.get(name, default)

    def getAttributeNS(self, ns, name, default=None):
        nsk = (ns, name)
        if self.attributes.has_key(nsk):
            return self.attributes[nsk]
        if ns == self.namespace:
            return self.attributes.get(name, default)
        return default

    def getAttributeNode(self, name):
        return _Attr(self.getAttribute(name), self)

    def setAttribute(self, name, attr):
        self.attributes[name] = attr

    def removeAttribute(self, name):
        if name in self.attributes:
            del self.attributes[name]

    def hasAttribute(self, name):
        return name in self.attributes


    def writexml(self, stream, indent='', addindent='', newl='', strip=0,
                 nsprefixes={}, namespace=''):
        """
        Serialize this L{Element} to the given stream.

        @param stream: A file-like object to which this L{Element} will be
            written.

        @param nsprefixes: A C{dict} mapping namespace URIs as C{str} to
            prefixes as C{str}.  This defines the prefixes which are already in
            scope in the document at the point at which this L{Element} exists.
            This is essentially an implementation detail for namespace support.
            Applications should not try to use it.

        @param namespace: The namespace URI as a C{str} which is the default at
            the point in the document at which this L{Element} exists.  This is
            essentially an implementation detail for namespace support.
            Applications should not try to use it.
        """
        # write beginning
        ALLOWSINGLETON = ('img', 'br', 'hr', 'base', 'meta', 'link', 'param',
                          'area', 'input', 'col', 'basefont', 'isindex',
                          'frame')
        BLOCKELEMENTS = ('html', 'head', 'body', 'noscript', 'ins', 'del',
                         'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'script',
                         'ul', 'ol', 'dl', 'pre', 'hr', 'blockquote',
                         'address', 'p', 'div', 'fieldset', 'table', 'tr',
                         'form', 'object', 'fieldset', 'applet', 'map')
        FORMATNICELY = ('tr', 'ul', 'ol', 'head')

        # this should never be necessary unless people start
        # changing .tagName on the fly(?)
        if not self.preserveCase:
            self.endTagName = self.tagName
        w = stream.write
        if self.nsprefixes:
            newprefixes = self.nsprefixes.copy()
            for ns in nsprefixes.keys():
                if ns in newprefixes:
                    del newprefixes[ns]
        else:
             newprefixes = {}

        begin = ['<']
        if self.tagName in BLOCKELEMENTS:
            begin = [newl, indent] + begin
        bext = begin.extend
        writeattr = lambda _atr, _val: bext((' ', _atr, '="', escape(_val), '"'))

        # Make a local for tracking what end tag will be used.  If namespace
        # prefixes are involved, this will be changed to account for that
        # before it's actually used.
        endTagName = self.endTagName

        if namespace != self.namespace and self.namespace is not None:
            # If the current default namespace is not the namespace of this tag
            # (and this tag has a namespace at all) then we'll write out
            # something related to namespaces.
            if self.namespace in nsprefixes:
                # This tag's namespace already has a prefix bound to it.  Use
                # that prefix.
                prefix = nsprefixes[self.namespace]
                bext(prefix + ':' + self.tagName)
                # Also make sure we use it for the end tag.
                endTagName = prefix + ':' + self.endTagName
            else:
                # This tag's namespace has no prefix bound to it.  Change the
                # default namespace to this tag's namespace so we don't need
                # prefixes.  Alternatively, we could add a new prefix binding.
                # I'm not sure why the code was written one way rather than the
                # other. -exarkun
                bext(self.tagName)
                writeattr("xmlns", self.namespace)
                # The default namespace just changed.  Make sure any children
                # know about this.
                namespace = self.namespace
        else:
            # This tag has no namespace or its namespace is already the default
            # namespace.  Nothing extra to do here.
            bext(self.tagName)

        j = ''.join
        for attr, val in self.attributes.iteritems():
            if isinstance(attr, tuple):
                ns, key = attr
                if nsprefixes.has_key(ns):
                    prefix = nsprefixes[ns]
                else:
                    prefix = genprefix()
                    newprefixes[ns] = prefix
                assert val is not None
                writeattr(prefix+':'+key,val)
            else:
                assert val is not None
                writeattr(attr, val)
        if newprefixes:
            for ns, prefix in newprefixes.iteritems():
                if prefix:
                    writeattr('xmlns:'+prefix, ns)
            newprefixes.update(nsprefixes)
            downprefixes = newprefixes
        else:
            downprefixes = nsprefixes
        w(j(begin))
        if self.childNodes:
            w(">")
            newindent = indent + addindent
            for child in self.childNodes:
                if self.tagName in BLOCKELEMENTS and \
                   self.tagName in FORMATNICELY:
                    w(j((newl, newindent)))
                child.writexml(stream, newindent, addindent, newl, strip,
                               downprefixes, namespace)
            if self.tagName in BLOCKELEMENTS:
                w(j((newl, indent)))
            w(j(('</', endTagName, '>')))
        elif self.tagName.lower() not in ALLOWSINGLETON:
            w(j(('></', endTagName, '>')))
        else:
            w(" />")


    def __repr__(self):
        rep = "Element(%s" % repr(self.nodeName)
        if self.attributes:
            rep += ", attributes=%r" % (self.attributes,)
        if self._filename:
            rep += ", filename=%r" % (self._filename,)
        if self._markpos:
            rep += ", markpos=%r" % (self._markpos,)
        return rep + ')'

    def __str__(self):
        rep = "<" + self.nodeName
        if self._filename or self._markpos:
            rep += " ("
        if self._filename:
            rep += repr(self._filename)
        if self._markpos:
            rep += " line %s column %s" % self._markpos
        if self._filename or self._markpos:
            rep += ")"
        for item in self.attributes.items():
            rep += " %s=%r" % item
        if self.hasChildNodes():
            rep += " >...</%s>" % self.nodeName
        else:
            rep += " />"
        return rep

def _unescapeDict(d):
    dd = {}
    for k, v in d.items():
        dd[k] = unescape(v)
    return dd

def _reverseDict(d):
    dd = {}
    for k, v in d.items():
        dd[v]=k
    return dd

class MicroDOMParser(XMLParser):

    # <dash> glyph: a quick scan thru the DTD says BODY, AREA, LINK, IMG, HR,
    # P, DT, DD, LI, INPUT, OPTION, THEAD, TFOOT, TBODY, COLGROUP, COL, TR, TH,
    # TD, HEAD, BASE, META, HTML all have optional closing tags

    soonClosers = 'area link br img hr input base meta'.split()
    laterClosers = {'p': ['p', 'dt'],
                    'dt': ['dt','dd'],
                    'dd': ['dt', 'dd'],
                    'li': ['li'],
                    'tbody': ['thead', 'tfoot', 'tbody'],
                    'thead': ['thead', 'tfoot', 'tbody'],
                    'tfoot': ['thead', 'tfoot', 'tbody'],
                    'colgroup': ['colgroup'],
                    'col': ['col'],
                    'tr': ['tr'],
                    'td': ['td'],
                    'th': ['th'],
                    'head': ['body'],
                    'title': ['head', 'body'], # this looks wrong...
                    'option': ['option'],
                    }


    def __init__(self, beExtremelyLenient=0, caseInsensitive=1, preserveCase=0,
                 soonClosers=soonClosers, laterClosers=laterClosers):
        self.elementstack = []
        d = {'xmlns': 'xmlns', '': None}
        dr = _reverseDict(d)
        self.nsstack = [(d,None,dr)]
        self.documents = []
        self._mddoctype = None
        self.beExtremelyLenient = beExtremelyLenient
        self.caseInsensitive = caseInsensitive
        self.preserveCase = preserveCase or not caseInsensitive
        self.soonClosers = soonClosers
        self.laterClosers = laterClosers
        # self.indentlevel = 0

    def shouldPreserveSpace(self):
        for edx in xrange(len(self.elementstack)):
            el = self.elementstack[-edx]
            if el.tagName == 'pre' or el.getAttribute("xml:space", '') == 'preserve':
                return 1
        return 0

    def _getparent(self):
        if self.elementstack:
            return self.elementstack[-1]
        else:
            return None

    COMMENT = re.compile(r"\s*/[/*]\s*")

    def _fixScriptElement(self, el):
        # this deals with case where there is comment or CDATA inside
        # <script> tag and we want to do the right thing with it
        if not self.beExtremelyLenient or not len(el.childNodes) == 1:
            return
        c = el.firstChild()
        if isinstance(c, Text):
            # deal with nasty people who do stuff like:
            #   <script> // <!--
            #      x = 1;
            #   // --></script>
            # tidy does this, for example.
            prefix = ""
            oldvalue = c.value
            match = self.COMMENT.match(oldvalue)
            if match:
                prefix = match.group()
                oldvalue = oldvalue[len(prefix):]

            # now see if contents are actual node and comment or CDATA
            try:
                e = parseString("<a>%s</a>" % oldvalue).childNodes[0]
            except (ParseError, MismatchedTags):
                return
            if len(e.childNodes) != 1:
                return
            e = e.firstChild()
            if isinstance(e, (CDATASection, Comment)):
                el.childNodes = []
                if prefix:
                    el.childNodes.append(Text(prefix))
                el.childNodes.append(e)

    def gotDoctype(self, doctype):
        self._mddoctype = doctype

    def gotTagStart(self, name, attributes):
        # print ' '*self.indentlevel, 'start tag',name
        # self.indentlevel += 1
        parent = self._getparent()
        if (self.beExtremelyLenient and isinstance(parent, Element)):
            parentName = parent.tagName
            myName = name
            if self.caseInsensitive:
                parentName = parentName.lower()
                myName = myName.lower()
            if myName in self.laterClosers.get(parentName, []):
                self.gotTagEnd(parent.tagName)
                parent = self._getparent()
        attributes = _unescapeDict(attributes)
        namespaces = self.nsstack[-1][0]
        newspaces = {}
        for k, v in attributes.items():
            if k.startswith('xmlns'):
                spacenames = k.split(':',1)
                if len(spacenames) == 2:
                    newspaces[spacenames[1]] = v
                else:
                    newspaces[''] = v
                del attributes[k]
        if newspaces:
            namespaces = namespaces.copy()
            namespaces.update(newspaces)
        for k, v in attributes.items():
            ksplit = k.split(':', 1)
            if len(ksplit) == 2:
                pfx, tv = ksplit
                if pfx != 'xml' and namespaces.has_key(pfx):
                    attributes[namespaces[pfx], tv] = v
                    del attributes[k]
        el = Element(name, attributes, parent,
                     self.filename, self.saveMark(),
                     caseInsensitive=self.caseInsensitive,
                     preserveCase=self.preserveCase,
                     namespace=namespaces.get(''))
        revspaces = _reverseDict(newspaces)
        el.addPrefixes(revspaces)

        if newspaces:
            rscopy = self.nsstack[-1][2].copy()
            rscopy.update(revspaces)
            self.nsstack.append((namespaces, el, rscopy))
        self.elementstack.append(el)
        if parent:
            parent.appendChild(el)
        if (self.beExtremelyLenient and el.tagName in self.soonClosers):
            self.gotTagEnd(name)

    def _gotStandalone(self, factory, data):
        parent = self._getparent()
        te = factory(data, parent)
        if parent:
            parent.appendChild(te)
        elif self.beExtremelyLenient:
            self.documents.append(te)

    def gotText(self, data):
        if data.strip() or self.shouldPreserveSpace():
            self._gotStandalone(Text, data)

    def gotComment(self, data):
        self._gotStandalone(Comment, data)

    def gotEntityReference(self, entityRef):
        self._gotStandalone(EntityReference, entityRef)

    def gotCData(self, cdata):
        self._gotStandalone(CDATASection, cdata)

    def gotTagEnd(self, name):
        # print ' '*self.indentlevel, 'end tag',name
        # self.indentlevel -= 1
        if not self.elementstack:
            if self.beExtremelyLenient:
                return
            raise MismatchedTags(*((self.filename, "NOTHING", name)
                                   +self.saveMark()+(0,0)))
        el = self.elementstack.pop()
        pfxdix = self.nsstack[-1][2]
        if self.nsstack[-1][1] is el:
            nstuple = self.nsstack.pop()
        else:
            nstuple = None
        if self.caseInsensitive:
            tn = el.tagName.lower()
            cname = name.lower()
        else:
            tn = el.tagName
            cname = name

        nsplit = name.split(':',1)
        if len(nsplit) == 2:
            pfx, newname = nsplit
            ns = pfxdix.get(pfx,None)
            if ns is not None:
                if el.namespace != ns:
                    if not self.beExtremelyLenient:
                        raise MismatchedTags(*((self.filename, el.tagName, name)
                                               +self.saveMark()+el._markpos))
        if not (tn == cname):
            if self.beExtremelyLenient:
                if self.elementstack:
                    lastEl = self.elementstack[0]
                    for idx in xrange(len(self.elementstack)):
                        if self.elementstack[-(idx+1)].tagName == cname:
                            self.elementstack[-(idx+1)].endTag(name)
                            break
                    else:
                        # this was a garbage close tag; wait for a real one
                        self.elementstack.append(el)
                        if nstuple is not None:
                            self.nsstack.append(nstuple)
                        return
                    del self.elementstack[-(idx+1):]
                    if not self.elementstack:
                        self.documents.append(lastEl)
                        return
            else:
                raise MismatchedTags(*((self.filename, el.tagName, name)
                                       +self.saveMark()+el._markpos))
        el.endTag(name)
        if not self.elementstack:
            self.documents.append(el)
        if self.beExtremelyLenient and el.tagName == "script":
            self._fixScriptElement(el)

    def connectionLost(self, reason):
        XMLParser.connectionLost(self, reason) # This can cause more events!
        if self.elementstack:
            if self.beExtremelyLenient:
                self.documents.append(self.elementstack[0])
            else:
                raise MismatchedTags(*((self.filename, self.elementstack[-1],
                                        "END_OF_FILE")
                                       +self.saveMark()
                                       +self.elementstack[-1]._markpos))


def parse(readable, *args, **kwargs):
    """Parse HTML or XML readable."""
    if not hasattr(readable, "read"):
        readable = open(readable, "rb")
    mdp = MicroDOMParser(*args, **kwargs)
    mdp.filename = getattr(readable, "name", "<xmlfile />")
    mdp.makeConnection(None)
    if hasattr(readable,"getvalue"):
        mdp.dataReceived(readable.getvalue())
    else:
        r = readable.read(1024)
        while r:
            mdp.dataReceived(r)
            r = readable.read(1024)
    mdp.connectionLost(None)

    if not mdp.documents:
        raise ParseError(mdp.filename, 0, 0, "No top-level Nodes in document")

    if mdp.beExtremelyLenient:
        if len(mdp.documents) == 1:
            d = mdp.documents[0]
            if not isinstance(d, Element):
                el = Element("html")
                el.appendChild(d)
                d = el
        else:
            d = Element("html")
            for child in mdp.documents:
                d.appendChild(child)
    else:
        d = mdp.documents[0]
    doc = Document(d)
    doc.doctype = mdp._mddoctype
    return doc

def parseString(st, *args, **kw):
    if isinstance(st, UnicodeType):
        # this isn't particularly ideal, but it does work.
        return parse(StringIO(st.encode('UTF-16')), *args, **kw)
    return parse(StringIO(st), *args, **kw)


def parseXML(readable):
    """Parse an XML readable object."""
    return parse(readable, caseInsensitive=0, preserveCase=1)


def parseXMLString(st):
    """Parse an XML readable object."""
    return parseString(st, caseInsensitive=0, preserveCase=1)


# Utility

class lmx:
    """Easy creation of XML."""

    def __init__(self, node='div'):
        if isinstance(node, StringTypes):
            node = Element(node)
        self.node = node

    def __getattr__(self, name):
        if name[0] == '_':
            raise AttributeError("no private attrs")
        return lambda **kw: self.add(name,**kw)

    def __setitem__(self, key, val):
        self.node.setAttribute(key, val)

    def __getitem__(self, key):
        return self.node.getAttribute(key)

    def text(self, txt, raw=0):
        nn = Text(txt, raw=raw)
        self.node.appendChild(nn)
        return self

    def add(self, tagName, **kw):
        newNode = Element(tagName, caseInsensitive=0, preserveCase=0)
        self.node.appendChild(newNode)
        xf = lmx(newNode)
        for k, v in kw.items():
            if k[0] == '_':
                k = k[1:]
            xf[k]=v
        return xf