""" Utilities for XML generation/parsing. """ import re from xml.sax.saxutils import XMLGenerator class UnserializableContentError(ValueError): pass class SimplerXMLGenerator(XMLGenerator): def addQuickElement(self, name, contents=None, attrs=None): "Convenience method for adding an element with no children" if attrs is None: attrs = {} self.startElement(name, attrs) if contents is not None: self.characters(contents) self.endElement(name) def characters(self, content): if content and re.search(r"[\x00-\x08\x0B-\x0C\x0E-\x1F]", content): # Fail loudly when content has control chars (unsupported in XML 1.0) # See https://www.w3.org/International/questions/qa-controls raise UnserializableContentError( "Control characters are not supported in XML 1.0" ) XMLGenerator.characters(self, content) def startElement(self, name, attrs): # Sort attrs for a deterministic output. sorted_attrs = dict(sorted(attrs.items())) if attrs else attrs super().startElement(name, sorted_attrs)