diff options
Diffstat (limited to 'Lib/xml/dom/xmlbuilder.py')
| -rw-r--r-- | Lib/xml/dom/xmlbuilder.py | 386 |
1 files changed, 386 insertions, 0 deletions
diff --git a/Lib/xml/dom/xmlbuilder.py b/Lib/xml/dom/xmlbuilder.py new file mode 100644 index 0000000..ac1d448 --- /dev/null +++ b/Lib/xml/dom/xmlbuilder.py @@ -0,0 +1,386 @@ +"""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() |