lib-python.2.7.xml.dom.expatbuilder.py Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jython Show documentation
Show all versions of jython Show documentation
Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
"""Facility to use the Expat parser to load a minidom instance
from a string or file.
This avoids all the overhead of SAX and pulldom to gain performance.
"""
# Warning!
#
# This module is tightly bound to the implementation details of the
# minidom DOM and can't be used with other DOM implementations. This
# is due, in part, to a lack of appropriate methods in the DOM (there is
# no way to create Entity and Notation nodes via the DOM Level 2
# interface), and for performance. The later is the cause of some fairly
# cryptic code.
#
# Performance hacks:
#
# - .character_data_handler() has an extra case in which continuing
# data is appended to an existing Text node; this can be a
# speedup since pyexpat can break up character data into multiple
# callbacks even though we set the buffer_text attribute on the
# parser. This also gives us the advantage that we don't need a
# separate normalization pass.
#
# - Determining that a node exists is done using an identity comparison
# with None rather than a truth test; this avoids searching for and
# calling any methods on the node object if it exists. (A rather
# nice speedup is achieved this way as well!)
from xml.dom import xmlbuilder, minidom, Node
from xml.dom import EMPTY_NAMESPACE, EMPTY_PREFIX, XMLNS_NAMESPACE
from xml.parsers import expat
from xml.dom.minidom import _append_child, _set_attribute_node
from xml.dom.NodeFilter import NodeFilter
from xml.dom.minicompat import *
TEXT_NODE = Node.TEXT_NODE
CDATA_SECTION_NODE = Node.CDATA_SECTION_NODE
DOCUMENT_NODE = Node.DOCUMENT_NODE
FILTER_ACCEPT = xmlbuilder.DOMBuilderFilter.FILTER_ACCEPT
FILTER_REJECT = xmlbuilder.DOMBuilderFilter.FILTER_REJECT
FILTER_SKIP = xmlbuilder.DOMBuilderFilter.FILTER_SKIP
FILTER_INTERRUPT = xmlbuilder.DOMBuilderFilter.FILTER_INTERRUPT
theDOMImplementation = minidom.getDOMImplementation()
# Expat typename -> TypeInfo
_typeinfo_map = {
"CDATA": minidom.TypeInfo(None, "cdata"),
"ENUM": minidom.TypeInfo(None, "enumeration"),
"ENTITY": minidom.TypeInfo(None, "entity"),
"ENTITIES": minidom.TypeInfo(None, "entities"),
"ID": minidom.TypeInfo(None, "id"),
"IDREF": minidom.TypeInfo(None, "idref"),
"IDREFS": minidom.TypeInfo(None, "idrefs"),
"NMTOKEN": minidom.TypeInfo(None, "nmtoken"),
"NMTOKENS": minidom.TypeInfo(None, "nmtokens"),
}
class ElementInfo(object):
__slots__ = '_attr_info', '_model', 'tagName'
def __init__(self, tagName, model=None):
self.tagName = tagName
self._attr_info = []
self._model = model
def __getstate__(self):
return self._attr_info, self._model, self.tagName
def __setstate__(self, state):
self._attr_info, self._model, self.tagName = state
def getAttributeType(self, aname):
for info in self._attr_info:
if info[1] == aname:
t = info[-2]
if t[0] == "(":
return _typeinfo_map["ENUM"]
else:
return _typeinfo_map[info[-2]]
return minidom._no_type
def getAttributeTypeNS(self, namespaceURI, localName):
return minidom._no_type
def isElementContent(self):
if self._model:
type = self._model[0]
return type not in (expat.model.XML_CTYPE_ANY,
expat.model.XML_CTYPE_MIXED)
else:
return False
def isEmpty(self):
if self._model:
return self._model[0] == expat.model.XML_CTYPE_EMPTY
else:
return False
def isId(self, aname):
for info in self._attr_info:
if info[1] == aname:
return info[-2] == "ID"
return False
def isIdNS(self, euri, ename, auri, aname):
# not sure this is meaningful
return self.isId((auri, aname))
def _intern(builder, s):
return builder._intern_setdefault(s, s)
def _parse_ns_name(builder, name):
assert ' ' in name
parts = name.split(' ')
intern = builder._intern_setdefault
if len(parts) == 3:
uri, localname, prefix = parts
prefix = intern(prefix, prefix)
qname = "%s:%s" % (prefix, localname)
qname = intern(qname, qname)
localname = intern(localname, localname)
else:
uri, localname = parts
prefix = EMPTY_PREFIX
qname = localname = intern(localname, localname)
return intern(uri, uri), localname, prefix, qname
class ExpatBuilder:
"""Document builder that uses Expat to build a ParsedXML.DOM document
instance."""
def __init__(self, options=None):
if options is None:
options = xmlbuilder.Options()
self._options = options
if self._options.filter is not None:
self._filter = FilterVisibilityController(self._options.filter)
else:
self._filter = None
# This *really* doesn't do anything in this case, so
# override it with something fast & minimal.
self._finish_start_element = id
self._parser = None
self.reset()
def createParser(self):
"""Create a new parser object."""
return expat.ParserCreate()
def getParser(self):
"""Return the parser object, creating a new one if needed."""
if not self._parser:
self._parser = self.createParser()
self._intern_setdefault = self._parser.intern.setdefault
self._parser.buffer_text = True
self._parser.ordered_attributes = True
self._parser.specified_attributes = True
self.install(self._parser)
return self._parser
def reset(self):
"""Free all data structures used during DOM construction."""
self.document = theDOMImplementation.createDocument(
EMPTY_NAMESPACE, None, None)
self.curNode = self.document
self._elem_info = self.document._elem_info
self._cdata = False
def install(self, parser):
"""Install the callbacks needed to build the DOM into the parser."""
# This creates circular references!
parser.StartDoctypeDeclHandler = self.start_doctype_decl_handler
parser.StartElementHandler = self.first_element_handler
parser.EndElementHandler = self.end_element_handler
parser.ProcessingInstructionHandler = self.pi_handler
if self._options.entities:
parser.EntityDeclHandler = self.entity_decl_handler
parser.NotationDeclHandler = self.notation_decl_handler
if self._options.comments:
parser.CommentHandler = self.comment_handler
if self._options.cdata_sections:
parser.StartCdataSectionHandler = self.start_cdata_section_handler
parser.EndCdataSectionHandler = self.end_cdata_section_handler
parser.CharacterDataHandler = self.character_data_handler_cdata
else:
parser.CharacterDataHandler = self.character_data_handler
parser.ExternalEntityRefHandler = self.external_entity_ref_handler
parser.XmlDeclHandler = self.xml_decl_handler
parser.ElementDeclHandler = self.element_decl_handler
parser.AttlistDeclHandler = self.attlist_decl_handler
def parseFile(self, file):
"""Parse a document from a file object, returning the document
node."""
parser = self.getParser()
first_buffer = True
try:
while 1:
buffer = file.read(16*1024)
if not buffer:
break
parser.Parse(buffer, 0)
if first_buffer and self.document.documentElement:
self._setup_subset(buffer)
first_buffer = False
parser.Parse("", True)
except ParseEscape:
pass
doc = self.document
self.reset()
self._parser = None
return doc
def parseString(self, string):
"""Parse a document from a string, returning the document node."""
parser = self.getParser()
try:
parser.Parse(string, True)
self._setup_subset(string)
except ParseEscape:
pass
doc = self.document
self.reset()
self._parser = None
return doc
def _setup_subset(self, buffer):
"""Load the internal subset if there might be one."""
if self.document.doctype:
extractor = InternalSubsetExtractor()
extractor.parseString(buffer)
subset = extractor.getSubset()
self.document.doctype.internalSubset = subset
def start_doctype_decl_handler(self, doctypeName, systemId, publicId,
has_internal_subset):
doctype = self.document.implementation.createDocumentType(
doctypeName, publicId, systemId)
doctype.ownerDocument = self.document
_append_child(self.document, doctype)
self.document.doctype = doctype
if self._filter and self._filter.acceptNode(doctype) == FILTER_REJECT:
self.document.doctype = None
del self.document.childNodes[-1]
doctype = None
self._parser.EntityDeclHandler = None
self._parser.NotationDeclHandler = None
if has_internal_subset:
if doctype is not None:
doctype.entities._seq = []
doctype.notations._seq = []
self._parser.CommentHandler = None
self._parser.ProcessingInstructionHandler = None
self._parser.EndDoctypeDeclHandler = self.end_doctype_decl_handler
def end_doctype_decl_handler(self):
if self._options.comments:
self._parser.CommentHandler = self.comment_handler
self._parser.ProcessingInstructionHandler = self.pi_handler
if not (self._elem_info or self._filter):
self._finish_end_element = id
def pi_handler(self, target, data):
node = self.document.createProcessingInstruction(target, data)
_append_child(self.curNode, node)
if self._filter and self._filter.acceptNode(node) == FILTER_REJECT:
self.curNode.removeChild(node)
def character_data_handler_cdata(self, data):
childNodes = self.curNode.childNodes
if self._cdata:
if ( self._cdata_continue
and childNodes[-1].nodeType == CDATA_SECTION_NODE):
childNodes[-1].appendData(data)
return
node = self.document.createCDATASection(data)
self._cdata_continue = True
elif childNodes and childNodes[-1].nodeType == TEXT_NODE:
node = childNodes[-1]
value = node.data + data
d = node.__dict__
d['data'] = d['nodeValue'] = value
return
else:
node = minidom.Text()
d = node.__dict__
d['data'] = d['nodeValue'] = data
d['ownerDocument'] = self.document
_append_child(self.curNode, node)
def character_data_handler(self, data):
childNodes = self.curNode.childNodes
if childNodes and childNodes[-1].nodeType == TEXT_NODE:
node = childNodes[-1]
d = node.__dict__
d['data'] = d['nodeValue'] = node.data + data
return
node = minidom.Text()
d = node.__dict__
d['data'] = d['nodeValue'] = node.data + data
d['ownerDocument'] = self.document
_append_child(self.curNode, node)
def entity_decl_handler(self, entityName, is_parameter_entity, value,
base, systemId, publicId, notationName):
if is_parameter_entity:
# we don't care about parameter entities for the DOM
return
if not self._options.entities:
return
node = self.document._create_entity(entityName, publicId,
systemId, notationName)
if value is not None:
# internal entity
# node *should* be readonly, but we'll cheat
child = self.document.createTextNode(value)
node.childNodes.append(child)
self.document.doctype.entities._seq.append(node)
if self._filter and self._filter.acceptNode(node) == FILTER_REJECT:
del self.document.doctype.entities._seq[-1]
def notation_decl_handler(self, notationName, base, systemId, publicId):
node = self.document._create_notation(notationName, publicId, systemId)
self.document.doctype.notations._seq.append(node)
if self._filter and self._filter.acceptNode(node) == FILTER_ACCEPT:
del self.document.doctype.notations._seq[-1]
def comment_handler(self, data):
node = self.document.createComment(data)
_append_child(self.curNode, node)
if self._filter and self._filter.acceptNode(node) == FILTER_REJECT:
self.curNode.removeChild(node)
def start_cdata_section_handler(self):
self._cdata = True
self._cdata_continue = False
def end_cdata_section_handler(self):
self._cdata = False
self._cdata_continue = False
def external_entity_ref_handler(self, context, base, systemId, publicId):
return 1
def first_element_handler(self, name, attributes):
if self._filter is None and not self._elem_info:
self._finish_end_element = id
self.getParser().StartElementHandler = self.start_element_handler
self.start_element_handler(name, attributes)
def start_element_handler(self, name, attributes):
node = self.document.createElement(name)
_append_child(self.curNode, node)
self.curNode = node
if attributes:
for i in range(0, len(attributes), 2):
a = minidom.Attr(attributes[i], EMPTY_NAMESPACE,
None, EMPTY_PREFIX)
value = attributes[i+1]
d = a.childNodes[0].__dict__
d['data'] = d['nodeValue'] = value
d = a.__dict__
d['value'] = d['nodeValue'] = value
d['ownerDocument'] = self.document
_set_attribute_node(node, a)
if node is not self.document.documentElement:
self._finish_start_element(node)
def _finish_start_element(self, node):
if self._filter:
# To be general, we'd have to call isSameNode(), but this
# is sufficient for minidom:
if node is self.document.documentElement:
return
filt = self._filter.startContainer(node)
if filt == FILTER_REJECT:
# ignore this node & all descendents
Rejecter(self)
elif filt == FILTER_SKIP:
# ignore this node, but make it's children become
# children of the parent node
Skipper(self)
else:
return
self.curNode = node.parentNode
node.parentNode.removeChild(node)
node.unlink()
# If this ever changes, Namespaces.end_element_handler() needs to
# be changed to match.
#
def end_element_handler(self, name):
curNode = self.curNode
self.curNode = curNode.parentNode
self._finish_end_element(curNode)
def _finish_end_element(self, curNode):
info = self._elem_info.get(curNode.tagName)
if info:
self._handle_white_text_nodes(curNode, info)
if self._filter:
if curNode is self.document.documentElement:
return
if self._filter.acceptNode(curNode) == FILTER_REJECT:
self.curNode.removeChild(curNode)
curNode.unlink()
def _handle_white_text_nodes(self, node, info):
if (self._options.whitespace_in_element_content
or not info.isElementContent()):
return
# We have element type information and should remove ignorable
# whitespace; identify for text nodes which contain only
# whitespace.
L = []
for child in node.childNodes:
if child.nodeType == TEXT_NODE and not child.data.strip():
L.append(child)
# Remove ignorable whitespace from the tree.
for child in L:
node.removeChild(child)
def element_decl_handler(self, name, model):
info = self._elem_info.get(name)
if info is None:
self._elem_info[name] = ElementInfo(name, model)
else:
assert info._model is None
info._model = model
def attlist_decl_handler(self, elem, name, type, default, required):
info = self._elem_info.get(elem)
if info is None:
info = ElementInfo(elem)
self._elem_info[elem] = info
info._attr_info.append(
[None, name, None, None, default, 0, type, required])
def xml_decl_handler(self, version, encoding, standalone):
self.document.version = version
self.document.encoding = encoding
# This is still a little ugly, thanks to the pyexpat API. ;-(
if standalone >= 0:
if standalone:
self.document.standalone = True
else:
self.document.standalone = False
# Don't include FILTER_INTERRUPT, since that's checked separately
# where allowed.
_ALLOWED_FILTER_RETURNS = (FILTER_ACCEPT, FILTER_REJECT, FILTER_SKIP)
class FilterVisibilityController(object):
"""Wrapper around a DOMBuilderFilter which implements the checks
to make the whatToShow filter attribute work."""
__slots__ = 'filter',
def __init__(self, filter):
self.filter = filter
def startContainer(self, node):
mask = self._nodetype_mask[node.nodeType]
if self.filter.whatToShow & mask:
val = self.filter.startContainer(node)
if val == FILTER_INTERRUPT:
raise ParseEscape
if val not in _ALLOWED_FILTER_RETURNS:
raise ValueError, \
"startContainer() returned illegal value: " + repr(val)
return val
else:
return FILTER_ACCEPT
def acceptNode(self, node):
mask = self._nodetype_mask[node.nodeType]
if self.filter.whatToShow & mask:
val = self.filter.acceptNode(node)
if val == FILTER_INTERRUPT:
raise ParseEscape
if val == FILTER_SKIP:
# move all child nodes to the parent, and remove this node
parent = node.parentNode
for child in node.childNodes[:]:
parent.appendChild(child)
# node is handled by the caller
return FILTER_REJECT
if val not in _ALLOWED_FILTER_RETURNS:
raise ValueError, \
"acceptNode() returned illegal value: " + repr(val)
return val
else:
return FILTER_ACCEPT
_nodetype_mask = {
Node.ELEMENT_NODE: NodeFilter.SHOW_ELEMENT,
Node.ATTRIBUTE_NODE: NodeFilter.SHOW_ATTRIBUTE,
Node.TEXT_NODE: NodeFilter.SHOW_TEXT,
Node.CDATA_SECTION_NODE: NodeFilter.SHOW_CDATA_SECTION,
Node.ENTITY_REFERENCE_NODE: NodeFilter.SHOW_ENTITY_REFERENCE,
Node.ENTITY_NODE: NodeFilter.SHOW_ENTITY,
Node.PROCESSING_INSTRUCTION_NODE: NodeFilter.SHOW_PROCESSING_INSTRUCTION,
Node.COMMENT_NODE: NodeFilter.SHOW_COMMENT,
Node.DOCUMENT_NODE: NodeFilter.SHOW_DOCUMENT,
Node.DOCUMENT_TYPE_NODE: NodeFilter.SHOW_DOCUMENT_TYPE,
Node.DOCUMENT_FRAGMENT_NODE: NodeFilter.SHOW_DOCUMENT_FRAGMENT,
Node.NOTATION_NODE: NodeFilter.SHOW_NOTATION,
}
class FilterCrutch(object):
__slots__ = '_builder', '_level', '_old_start', '_old_end'
def __init__(self, builder):
self._level = 0
self._builder = builder
parser = builder._parser
self._old_start = parser.StartElementHandler
self._old_end = parser.EndElementHandler
parser.StartElementHandler = self.start_element_handler
parser.EndElementHandler = self.end_element_handler
class Rejecter(FilterCrutch):
__slots__ = ()
def __init__(self, builder):
FilterCrutch.__init__(self, builder)
parser = builder._parser
for name in ("ProcessingInstructionHandler",
"CommentHandler",
"CharacterDataHandler",
"StartCdataSectionHandler",
"EndCdataSectionHandler",
"ExternalEntityRefHandler",
):
setattr(parser, name, None)
def start_element_handler(self, *args):
self._level = self._level + 1
def end_element_handler(self, *args):
if self._level == 0:
# restore the old handlers
parser = self._builder._parser
self._builder.install(parser)
parser.StartElementHandler = self._old_start
parser.EndElementHandler = self._old_end
else:
self._level = self._level - 1
class Skipper(FilterCrutch):
__slots__ = ()
def start_element_handler(self, *args):
node = self._builder.curNode
self._old_start(*args)
if self._builder.curNode is not node:
self._level = self._level + 1
def end_element_handler(self, *args):
if self._level == 0:
# We're popping back out of the node we're skipping, so we
# shouldn't need to do anything but reset the handlers.
self._builder._parser.StartElementHandler = self._old_start
self._builder._parser.EndElementHandler = self._old_end
self._builder = None
else:
self._level = self._level - 1
self._old_end(*args)
# framework document used by the fragment builder.
# Takes a string for the doctype, subset string, and namespace attrs string.
_FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID = \
"http://xml.python.org/entities/fragment-builder/internal"
_FRAGMENT_BUILDER_TEMPLATE = (
'''\
%%s
]>
&fragment-builder-internal; '''
% _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID)
class FragmentBuilder(ExpatBuilder):
"""Builder which constructs document fragments given XML source
text and a context node.
The context node is expected to provide information about the
namespace declarations which are in scope at the start of the
fragment.
"""
def __init__(self, context, options=None):
if context.nodeType == DOCUMENT_NODE:
self.originalDocument = context
self.context = context
else:
self.originalDocument = context.ownerDocument
self.context = context
ExpatBuilder.__init__(self, options)
def reset(self):
ExpatBuilder.reset(self)
self.fragment = None
def parseFile(self, file):
"""Parse a document fragment from a file object, returning the
fragment node."""
return self.parseString(file.read())
def parseString(self, string):
"""Parse a document fragment from a string, returning the
fragment node."""
self._source = string
parser = self.getParser()
doctype = self.originalDocument.doctype
ident = ""
if doctype:
subset = doctype.internalSubset or self._getDeclarations()
if doctype.publicId:
ident = ('PUBLIC "%s" "%s"'
% (doctype.publicId, doctype.systemId))
elif doctype.systemId:
ident = 'SYSTEM "%s"' % doctype.systemId
else:
subset = ""
nsattrs = self._getNSattrs() # get ns decls from node's ancestors
document = _FRAGMENT_BUILDER_TEMPLATE % (ident, subset, nsattrs)
try:
parser.Parse(document, 1)
except:
self.reset()
raise
fragment = self.fragment
self.reset()
## self._parser = None
return fragment
def _getDeclarations(self):
"""Re-create the internal subset from the DocumentType node.
This is only needed if we don't already have the
internalSubset as a string.
"""
doctype = self.context.ownerDocument.doctype
s = ""
if doctype:
for i in range(doctype.notations.length):
notation = doctype.notations.item(i)
if s:
s = s + "\n "
s = "%s' \
% (s, notation.publicId, notation.systemId)
else:
s = '%s SYSTEM "%s">' % (s, notation.systemId)
for i in range(doctype.entities.length):
entity = doctype.entities.item(i)
if s:
s = s + "\n "
s = "%s"
return s
def _getNSattrs(self):
return ""
def external_entity_ref_handler(self, context, base, systemId, publicId):
if systemId == _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID:
# this entref is the one that we made to put the subtree
# in; all of our given input is parsed in here.
old_document = self.document
old_cur_node = self.curNode
parser = self._parser.ExternalEntityParserCreate(context)
# put the real document back, parse into the fragment to return
self.document = self.originalDocument
self.fragment = self.document.createDocumentFragment()
self.curNode = self.fragment
try:
parser.Parse(self._source, 1)
finally:
self.curNode = old_cur_node
self.document = old_document
self._source = None
return -1
else:
return ExpatBuilder.external_entity_ref_handler(
self, context, base, systemId, publicId)
class Namespaces:
"""Mix-in class for builders; adds support for namespaces."""
def _initNamespaces(self):
# list of (prefix, uri) ns declarations. Namespace attrs are
# constructed from this and added to the element's attrs.
self._ns_ordered_prefixes = []
def createParser(self):
"""Create a new namespace-handling parser."""
parser = expat.ParserCreate(namespace_separator=" ")
parser.namespace_prefixes = True
return parser
def install(self, parser):
"""Insert the namespace-handlers onto the parser."""
ExpatBuilder.install(self, parser)
if self._options.namespace_declarations:
parser.StartNamespaceDeclHandler = (
self.start_namespace_decl_handler)
def start_namespace_decl_handler(self, prefix, uri):
"""Push this namespace declaration on our storage."""
self._ns_ordered_prefixes.append((prefix, uri))
def start_element_handler(self, name, attributes):
if ' ' in name:
uri, localname, prefix, qname = _parse_ns_name(self, name)
else:
uri = EMPTY_NAMESPACE
qname = name
localname = None
prefix = EMPTY_PREFIX
node = minidom.Element(qname, uri, prefix, localname)
node.ownerDocument = self.document
_append_child(self.curNode, node)
self.curNode = node
if self._ns_ordered_prefixes:
for prefix, uri in self._ns_ordered_prefixes:
if prefix:
a = minidom.Attr(_intern(self, 'xmlns:' + prefix),
XMLNS_NAMESPACE, prefix, "xmlns")
else:
a = minidom.Attr("xmlns", XMLNS_NAMESPACE,
"xmlns", EMPTY_PREFIX)
d = a.childNodes[0].__dict__
d['data'] = d['nodeValue'] = uri
d = a.__dict__
d['value'] = d['nodeValue'] = uri
d['ownerDocument'] = self.document
_set_attribute_node(node, a)
del self._ns_ordered_prefixes[:]
if attributes:
_attrs = node._attrs
_attrsNS = node._attrsNS
for i in range(0, len(attributes), 2):
aname = attributes[i]
value = attributes[i+1]
if ' ' in aname:
uri, localname, prefix, qname = _parse_ns_name(self, aname)
a = minidom.Attr(qname, uri, localname, prefix)
_attrs[qname] = a
_attrsNS[(uri, localname)] = a
else:
a = minidom.Attr(aname, EMPTY_NAMESPACE,
aname, EMPTY_PREFIX)
_attrs[aname] = a
_attrsNS[(EMPTY_NAMESPACE, aname)] = a
d = a.childNodes[0].__dict__
d['data'] = d['nodeValue'] = value
d = a.__dict__
d['ownerDocument'] = self.document
d['value'] = d['nodeValue'] = value
d['ownerElement'] = node
if __debug__:
# This only adds some asserts to the original
# end_element_handler(), so we only define this when -O is not
# used. If changing one, be sure to check the other to see if
# it needs to be changed as well.
#
def end_element_handler(self, name):
curNode = self.curNode
if ' ' in name:
uri, localname, prefix, qname = _parse_ns_name(self, name)
assert (curNode.namespaceURI == uri
and curNode.localName == localname
and curNode.prefix == prefix), \
"element stack messed up! (namespace)"
else:
assert curNode.nodeName == name, \
"element stack messed up - bad nodeName"
assert curNode.namespaceURI == EMPTY_NAMESPACE, \
"element stack messed up - bad namespaceURI"
self.curNode = curNode.parentNode
self._finish_end_element(curNode)
class ExpatBuilderNS(Namespaces, ExpatBuilder):
"""Document builder that supports namespaces."""
def reset(self):
ExpatBuilder.reset(self)
self._initNamespaces()
class FragmentBuilderNS(Namespaces, FragmentBuilder):
"""Fragment builder that supports namespaces."""
def reset(self):
FragmentBuilder.reset(self)
self._initNamespaces()
def _getNSattrs(self):
"""Return string of namespace attributes from this element and
ancestors."""
# XXX This needs to be re-written to walk the ancestors of the
# context to build up the namespace information from
# declarations, elements, and attributes found in context.
# Otherwise we have to store a bunch more data on the DOM
# (though that *might* be more reliable -- not clear).
attrs = ""
context = self.context
L = []
while context:
if hasattr(context, '_ns_prefix_uri'):
for prefix, uri in context._ns_prefix_uri.items():
# add every new NS decl from context to L and attrs string
if prefix in L:
continue
L.append(prefix)
if prefix:
declname = "xmlns:" + prefix
else:
declname = "xmlns"
if attrs:
attrs = "%s\n %s='%s'" % (attrs, declname, uri)
else:
attrs = " %s='%s'" % (declname, uri)
context = context.parentNode
return attrs
class ParseEscape(Exception):
"""Exception raised to short-circuit parsing in InternalSubsetExtractor."""
pass
class InternalSubsetExtractor(ExpatBuilder):
"""XML processor which can rip out the internal document type subset."""
subset = None
def getSubset(self):
"""Return the internal subset as a string."""
return self.subset
def parseFile(self, file):
try:
ExpatBuilder.parseFile(self, file)
except ParseEscape:
pass
def parseString(self, string):
try:
ExpatBuilder.parseString(self, string)
except ParseEscape:
pass
def install(self, parser):
parser.StartDoctypeDeclHandler = self.start_doctype_decl_handler
parser.StartElementHandler = self.start_element_handler
def start_doctype_decl_handler(self, name, publicId, systemId,
has_internal_subset):
if has_internal_subset:
parser = self.getParser()
self.subset = []
parser.DefaultHandler = self.subset.append
parser.EndDoctypeDeclHandler = self.end_doctype_decl_handler
else:
raise ParseEscape()
def end_doctype_decl_handler(self):
s = ''.join(self.subset).replace('\r\n', '\n').replace('\r', '\n')
self.subset = s
raise ParseEscape()
def start_element_handler(self, name, attrs):
raise ParseEscape()
def parse(file, namespaces=True):
"""Parse a document, returning the resulting Document node.
'file' may be either a file name or an open file object.
"""
if namespaces:
builder = ExpatBuilderNS()
else:
builder = ExpatBuilder()
if isinstance(file, StringTypes):
fp = open(file, 'rb')
try:
result = builder.parseFile(fp)
finally:
fp.close()
else:
result = builder.parseFile(file)
return result
def parseString(string, namespaces=True):
"""Parse a document from a string, returning the resulting
Document node.
"""
if namespaces:
builder = ExpatBuilderNS()
else:
builder = ExpatBuilder()
return builder.parseString(string)
def parseFragment(file, context, namespaces=True):
"""Parse a fragment of a document, given the context from which it
was originally extracted. context should be the parent of the
node(s) which are in the fragment.
'file' may be either a file name or an open file object.
"""
if namespaces:
builder = FragmentBuilderNS(context)
else:
builder = FragmentBuilder(context)
if isinstance(file, StringTypes):
fp = open(file, 'rb')
try:
result = builder.parseFile(fp)
finally:
fp.close()
else:
result = builder.parseFile(file)
return result
def parseFragmentString(string, context, namespaces=True):
"""Parse a fragment of a document from a string, given the context
from which it was originally extracted. context should be the
parent of the node(s) which are in the fragment.
"""
if namespaces:
builder = FragmentBuilderNS(context)
else:
builder = FragmentBuilder(context)
return builder.parseString(string)
def makeBuilder(options):
"""Create a builder based on an Options object."""
if options.namespaces:
return ExpatBuilderNS(options)
else:
return ExpatBuilder(options)