Merge pull request #585 from johanlundberg/fix_xmlsec_sign_statement

Python 3 problem with lxml.etree.tostring

Author: c00kiemon5ter

src/saml2/sigver.py

@@ -957,7 +957,10 @@ def sign_statement(self, statement, node_name, key_file, node_id, id_attr):
 
         xml = xmlsec.parse_xml(statement)
         signed = xmlsec.sign(xml, key_file)
-        return lxml.etree.tostring(signed, xml_declaration=True)
+        signed_str = lxml.etree.tostring(signed, xml_declaration=False, encoding="UTF-8")
+        if not isinstance(signed_str, six.string_types):
+            signed_str = signed_str.decode("utf-8")
+        return signed_str
 
     def validate_signature(self, signedtext, cert_file, cert_type, node_name, node_id, id_attr):
         """