# -*- coding: utf-8 -*- """ sleekxmpp.xmlstream.tostring ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This module converts XML objects into Unicode strings and intelligently includes namespaces only when necessary to keep the output readable. Part of SleekXMPP: The Sleek XMPP Library :copyright: (c) 2011 Nathanael C. Fritz :license: MIT, see LICENSE for more details """ import sys if sys.version_info < (3, 0): import types def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer='', top_level=False): """Serialize an XML object to a Unicode string. If namespaces are provided using ``xmlns`` or ``stanza_ns``, then elements that use those namespaces will not include the xmlns attribute in the output. :param XML xml: The XML object to serialize. :param string xmlns: Optional namespace of an element wrapping the XML object. :param string stanza_ns: The namespace of the stanza object that contains the XML object. :param stream: The XML stream that generated the XML object. :param string outbuffer: Optional buffer for storing serializations during recursive calls. :param bool top_level: Indicates that the element is the outermost element. :type xml: :py:class:`~xml.etree.ElementTree.Element` :type stream: :class:`~sleekxmpp.xmlstream.xmlstream.XMLStream` :rtype: Unicode string """ # Add previous results to the start of the output. output = [outbuffer] # Extract the element's tag name. tag_name = xml.tag.split('}', 1)[-1] # Extract the element's namespace if it is defined. if '}' in xml.tag: tag_xmlns = xml.tag.split('}', 1)[0][1:] else: tag_xmlns = '' default_ns = '' stream_ns = '' if stream: default_ns = stream.default_ns stream_ns = stream.stream_ns # Output the tag name and derived namespace of the element. namespace = '' if top_level and tag_xmlns not in ['', default_ns, stream_ns] or \ tag_xmlns not in ['', xmlns, stanza_ns, stream_ns]: namespace = ' xmlns="%s"' % tag_xmlns if stream and tag_xmlns in stream.namespace_map: mapped_namespace = stream.namespace_map[tag_xmlns] if mapped_namespace: tag_name = "%s:%s" % (mapped_namespace, tag_name) output.append("<%s" % tag_name) output.append(namespace) # Output escaped attribute values. for attrib, value in xml.attrib.items(): value = xml_escape(value) if '}' not in attrib: output.append(' %s="%s"' % (attrib, value)) else: attrib_ns = attrib.split('}')[0][1:] attrib = attrib.split('}')[1] if stream and attrib_ns in stream.namespace_map: mapped_ns = stream.namespace_map[attrib_ns] if mapped_ns: output.append(' %s:%s="%s"' % (mapped_ns, attrib, value)) if len(xml) or xml.text: # If there are additional child elements to serialize. output.append(">") if xml.text: output.append(xml_escape(xml.text)) if len(xml): for child in xml.getchildren(): output.append(tostring(child, tag_xmlns, stanza_ns, stream)) output.append("</%s>" % tag_name) elif xml.text: # If we only have text content. output.append(">%s</%s>" % (xml_escape(xml.text), tag_name)) else: # Empty element. output.append(" />") if xml.tail: # If there is additional text after the element. output.append(xml_escape(xml.tail)) return ''.join(output) def xml_escape(text): """Convert special characters in XML to escape sequences. :param string text: The XML text to convert. :rtype: Unicode string """ if sys.version_info < (3, 0): if type(text) != types.UnicodeType: text = unicode(text, 'utf-8', 'ignore') text = list(text) escapes = {'&': '&', '<': '<', '>': '>', "'": ''', '"': '"'} for i, c in enumerate(text): text[i] = escapes.get(c, c) return ''.join(text)