'Determines and sets the document\'s metadata on self.'

def _get_metadata(self):

    if (not self._document):
        self._get_document()
    self['canonical_url'] = self._get_canonical_url()
    self['description'] = self._get_description()
    self['icon'] = self._get_icon()
    self['keywords'] = self._get_keywords()
    self['name'] = self._get_name()
