""" SleekXMPP: The Sleek XMPP Library Copyright (C) 2010 Nathanael C. Fritz This file is part of SleekXMPP. See the file LICENSE for copying permission. """ import logging from xml.parsers.expat import ExpatError from sleekxmpp.xmlstream.stanzabase import ET from sleekxmpp.xmlstream.matcher.base import MatcherBase log = logging.getLogger(__name__) class MatchXMLMask(MatcherBase): """ The XMLMask matcher selects stanzas whose XML matches a given XML pattern, or mask. For example, message stanzas with body elements could be matched using the mask: .. code-block:: xml <message xmlns="jabber:client"><body /></message> Use of XMLMask is discouraged, and :class:`~sleekxmpp.xmlstream.matcher.xpath.MatchXPath` or :class:`~sleekxmpp.xmlstream.matcher.stanzapath.StanzaPath` should be used instead. :param criteria: Either an :class:`~xml.etree.ElementTree.Element` XML object or XML string to use as a mask. """ def __init__(self, criteria): MatcherBase.__init__(self, criteria) if isinstance(criteria, str): self._criteria = ET.fromstring(self._criteria) self.default_ns = 'jabber:client' def setDefaultNS(self, ns): """Set the default namespace to use during comparisons. :param ns: The new namespace to use as the default. """ self.default_ns = ns def match(self, xml): """Compare a stanza object or XML object against the stored XML mask. Overrides MatcherBase.match. :param xml: The stanza object or XML object to compare against. """ if hasattr(xml, 'xml'): xml = xml.xml return self._mask_cmp(xml, self._criteria, True) def _mask_cmp(self, source, mask, use_ns=False, default_ns='__no_ns__'): """Compare an XML object against an XML mask. :param source: The :class:`~xml.etree.ElementTree.Element` XML object to compare against the mask. :param mask: The :class:`~xml.etree.ElementTree.Element` XML object serving as the mask. :param use_ns: Indicates if namespaces should be respected during the comparison. :default_ns: The default namespace to apply to elements that do not have a specified namespace. Defaults to ``"__no_ns__"``. """ if source is None: # If the element was not found. May happend during recursive calls. return False # Convert the mask to an XML object if it is a string. if not hasattr(mask, 'attrib'): try: mask = ET.fromstring(mask) except ExpatError: log.warning("Expat error: %s\nIn parsing: %s", '', mask) mask_ns_tag = "{%s}%s" % (self.default_ns, mask.tag) if source.tag not in [mask.tag, mask_ns_tag]: return False # If the mask includes text, compare it. if mask.text and source.text and \ source.text.strip() != mask.text.strip(): return False # Compare attributes. The stanza must include the attributes # defined by the mask, but may include others. for name, value in mask.attrib.items(): if source.attrib.get(name, "__None__") != value: return False # Recursively check subelements. matched_elements = {} for subelement in mask: matched = False for other in source.findall(subelement.tag): matched_elements[other] = False if self._mask_cmp(other, subelement, use_ns): if not matched_elements.get(other, False): matched_elements[other] = True matched = True if not matched: return False # Everything matches. return True