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- """Implementation of the DOM Level 3 'LS-Load' feature."""
-
- import copy
- import xml.dom
-
- from xml.dom.NodeFilter import NodeFilter
-
-
- __all__ = ["DOMBuilder", "DOMEntityResolver", "DOMInputSource"]
-
-
- class Options:
- """Features object that has variables set for each DOMBuilder feature.
-
- The DOMBuilder class uses an instance of this class to pass settings to
- the ExpatBuilder class.
- """
-
- # Note that the DOMBuilder class in LoadSave constrains which of these
- # values can be set using the DOM Level 3 LoadSave feature.
-
- namespaces = 1
- namespace_declarations = True
- validation = False
- external_parameter_entities = True
- external_general_entities = True
- external_dtd_subset = True
- validate_if_schema = False
- validate = False
- datatype_normalization = False
- create_entity_ref_nodes = True
- entities = True
- whitespace_in_element_content = True
- cdata_sections = True
- comments = True
- charset_overrides_xml_encoding = True
- infoset = False
- supported_mediatypes_only = False
-
- errorHandler = None
- filter = None
-
-
- class DOMBuilder:
- entityResolver = None
- errorHandler = None
- filter = None
-
- ACTION_REPLACE = 1
- ACTION_APPEND_AS_CHILDREN = 2
- ACTION_INSERT_AFTER = 3
- ACTION_INSERT_BEFORE = 4
-
- _legal_actions = (ACTION_REPLACE, ACTION_APPEND_AS_CHILDREN,
- ACTION_INSERT_AFTER, ACTION_INSERT_BEFORE)
-
- def __init__(self):
- self._options = Options()
-
- def _get_entityResolver(self):
- return self.entityResolver
- def _set_entityResolver(self, entityResolver):
- self.entityResolver = entityResolver
-
- def _get_errorHandler(self):
- return self.errorHandler
- def _set_errorHandler(self, errorHandler):
- self.errorHandler = errorHandler
-
- def _get_filter(self):
- return self.filter
- def _set_filter(self, filter):
- self.filter = filter
-
- def setFeature(self, name, state):
- if self.supportsFeature(name):
- state = state and 1 or 0
- try:
- settings = self._settings[(_name_xform(name), state)]
- except KeyError:
- raise xml.dom.NotSupportedErr(
- "unsupported feature: %r" % (name,))
- else:
- for name, value in settings:
- setattr(self._options, name, value)
- else:
- raise xml.dom.NotFoundErr("unknown feature: " + repr(name))
-
- def supportsFeature(self, name):
- return hasattr(self._options, _name_xform(name))
-
- def canSetFeature(self, name, state):
- key = (_name_xform(name), state and 1 or 0)
- return self._settings.has_key(key)
-
- # This dictionary maps from (feature,value) to a list of
- # (option,value) pairs that should be set on the Options object.
- # If a (feature,value) setting is not in this dictionary, it is
- # not supported by the DOMBuilder.
- #
- _settings = {
- ("namespace_declarations", 0): [
- ("namespace_declarations", 0)],
- ("namespace_declarations", 1): [
- ("namespace_declarations", 1)],
- ("validation", 0): [
- ("validation", 0)],
- ("external_general_entities", 0): [
- ("external_general_entities", 0)],
- ("external_general_entities", 1): [
- ("external_general_entities", 1)],
- ("external_parameter_entities", 0): [
- ("external_parameter_entities", 0)],
- ("external_parameter_entities", 1): [
- ("external_parameter_entities", 1)],
- ("validate_if_schema", 0): [
- ("validate_if_schema", 0)],
- ("create_entity_ref_nodes", 0): [
- ("create_entity_ref_nodes", 0)],
- ("create_entity_ref_nodes", 1): [
- ("create_entity_ref_nodes", 1)],
- ("entities", 0): [
- ("create_entity_ref_nodes", 0),
- ("entities", 0)],
- ("entities", 1): [
- ("entities", 1)],
- ("whitespace_in_element_content", 0): [
- ("whitespace_in_element_content", 0)],
- ("whitespace_in_element_content", 1): [
- ("whitespace_in_element_content", 1)],
- ("cdata_sections", 0): [
- ("cdata_sections", 0)],
- ("cdata_sections", 1): [
- ("cdata_sections", 1)],
- ("comments", 0): [
- ("comments", 0)],
- ("comments", 1): [
- ("comments", 1)],
- ("charset_overrides_xml_encoding", 0): [
- ("charset_overrides_xml_encoding", 0)],
- ("charset_overrides_xml_encoding", 1): [
- ("charset_overrides_xml_encoding", 1)],
- ("infoset", 0): [],
- ("infoset", 1): [
- ("namespace_declarations", 0),
- ("validate_if_schema", 0),
- ("create_entity_ref_nodes", 0),
- ("entities", 0),
- ("cdata_sections", 0),
- ("datatype_normalization", 1),
- ("whitespace_in_element_content", 1),
- ("comments", 1),
- ("charset_overrides_xml_encoding", 1)],
- ("supported_mediatypes_only", 0): [
- ("supported_mediatypes_only", 0)],
- ("namespaces", 0): [
- ("namespaces", 0)],
- ("namespaces", 1): [
- ("namespaces", 1)],
- }
-
- def getFeature(self, name):
- xname = _name_xform(name)
- try:
- return getattr(self._options, xname)
- except AttributeError:
- if name == "infoset":
- options = self._options
- return (options.datatype_normalization
- and options.whitespace_in_element_content
- and options.comments
- and options.charset_overrides_xml_encoding
- and not (options.namespace_declarations
- or options.validate_if_schema
- or options.create_entity_ref_nodes
- or options.entities
- or options.cdata_sections))
- raise xml.dom.NotFoundErr("feature %s not known" % repr(name))
-
- def parseURI(self, uri):
- if self.entityResolver:
- input = self.entityResolver.resolveEntity(None, uri)
- else:
- input = DOMEntityResolver().resolveEntity(None, uri)
- return self.parse(input)
-
- def parse(self, input):
- options = copy.copy(self._options)
- options.filter = self.filter
- options.errorHandler = self.errorHandler
- fp = input.byteStream
- if fp is None and options.systemId:
- import urllib2
- fp = urllib2.urlopen(input.systemId)
- return self._parse_bytestream(fp, options)
-
- def parseWithContext(self, input, cnode, action):
- if action not in self._legal_actions:
- raise ValueError("not a legal action")
- raise NotImplementedError("Haven't written this yet...")
-
- def _parse_bytestream(self, stream, options):
- import xml.dom.expatbuilder
- builder = xml.dom.expatbuilder.makeBuilder(options)
- return builder.parseFile(stream)
-
-
- def _name_xform(name):
- return name.lower().replace('-', '_')
-
-
- class DOMEntityResolver(object):
- __slots__ = '_opener',
-
- def resolveEntity(self, publicId, systemId):
- assert systemId is not None
- source = DOMInputSource()
- source.publicId = publicId
- source.systemId = systemId
- source.byteStream = self._get_opener().open(systemId)
-
- # determine the encoding if the transport provided it
- source.encoding = self._guess_media_encoding(source)
-
- # determine the base URI is we can
- import posixpath, urlparse
- parts = urlparse.urlparse(systemId)
- scheme, netloc, path, params, query, fragment = parts
- # XXX should we check the scheme here as well?
- if path and not path.endswith("/"):
- path = posixpath.dirname(path) + "/"
- parts = scheme, netloc, path, params, query, fragment
- source.baseURI = urlparse.urlunparse(parts)
-
- return source
-
- def _get_opener(self):
- try:
- return self._opener
- except AttributeError:
- self._opener = self._create_opener()
- return self._opener
-
- def _create_opener(self):
- import urllib2
- return urllib2.build_opener()
-
- def _guess_media_encoding(self, source):
- info = source.byteStream.info()
- if info.has_key("Content-Type"):
- for param in info.getplist():
- if param.startswith("charset="):
- return param.split("=", 1)[1].lower()
-
-
- class DOMInputSource(object):
- __slots__ = ('byteStream', 'characterStream', 'stringData',
- 'encoding', 'publicId', 'systemId', 'baseURI')
-
- def __init__(self):
- self.byteStream = None
- self.characterStream = None
- self.stringData = None
- self.encoding = None
- self.publicId = None
- self.systemId = None
- self.baseURI = None
-
- def _get_byteStream(self):
- return self.byteStream
- def _set_byteStream(self, byteStream):
- self.byteStream = byteStream
-
- def _get_characterStream(self):
- return self.characterStream
- def _set_characterStream(self, characterStream):
- self.characterStream = characterStream
-
- def _get_stringData(self):
- return self.stringData
- def _set_stringData(self, data):
- self.stringData = data
-
- def _get_encoding(self):
- return self.encoding
- def _set_encoding(self, encoding):
- self.encoding = encoding
-
- def _get_publicId(self):
- return self.publicId
- def _set_publicId(self, publicId):
- self.publicId = publicId
-
- def _get_systemId(self):
- return self.systemId
- def _set_systemId(self, systemId):
- self.systemId = systemId
-
- def _get_baseURI(self):
- return self.baseURI
- def _set_baseURI(self, uri):
- self.baseURI = uri
-
-
- class DOMBuilderFilter:
- """Element filter which can be used to tailor construction of
- a DOM instance.
- """
-
- # There's really no need for this class; concrete implementations
- # should just implement the endElement() and startElement()
- # methods as appropriate. Using this makes it easy to only
- # implement one of them.
-
- FILTER_ACCEPT = 1
- FILTER_REJECT = 2
- FILTER_SKIP = 3
- FILTER_INTERRUPT = 4
-
- whatToShow = NodeFilter.SHOW_ALL
-
- def _get_whatToShow(self):
- return self.whatToShow
-
- def acceptNode(self, element):
- return self.FILTER_ACCEPT
-
- def startContainer(self, element):
- return self.FILTER_ACCEPT
-
- del NodeFilter
-
-
- class DocumentLS:
- """Mixin to create documents that conform to the load/save spec."""
-
- async = False
-
- def _get_async(self):
- return False
- def _set_async(self, async):
- if async:
- raise xml.dom.NotSupportedErr(
- "asynchronous document loading is not supported")
-
- def abort(self):
- # What does it mean to "clear" a document? Does the
- # documentElement disappear?
- raise NotImplementedError(
- "haven't figured out what this means yet")
-
- def load(self, uri):
- raise NotImplementedError("haven't written this yet")
-
- def loadXML(self, source):
- raise NotImplementedError("haven't written this yet")
-
- def saveXML(self, snode):
- if snode is None:
- snode = self
- elif snode.ownerDocument is not self:
- raise xml.dom.WrongDocumentErr()
- return snode.toxml()
-
-
- class DOMImplementationLS:
- MODE_SYNCHRONOUS = 1
- MODE_ASYNCHRONOUS = 2
-
- def createDOMBuilder(self, mode, schemaType):
- if schemaType is not None:
- raise xml.dom.NotSupportedErr(
- "schemaType not yet supported")
- if mode == self.MODE_SYNCHRONOUS:
- return DOMBuilder()
- if mode == self.MODE_ASYNCHRONOUS:
- raise xml.dom.NotSupportedErr(
- "asynchronous builders are not supported")
- raise ValueError("unknown value for mode")
-
- def createDOMWriter(self):
- raise NotImplementedError(
- "the writer interface hasn't been written yet!")
-
- def createDOMInputSource(self):
- return DOMInputSource()
-