handle malformed OpenSearch requests gracefully

Author: tomkralidis

pycsw/opensearch.py

@@ -57,7 +57,11 @@ def __init__(self, context):
     def response_csw2opensearch(self, element, cfg):
         """transform a CSW response into an OpenSearch response"""
 
-        LOGGER.debug('RESPONSE: %s', util.xmltag_split(element.tag))
+        root_tag = util.xmltag_split(element.tag)
+        if root_tag == 'ExceptionReport':
+            return element
+
+        LOGGER.debug('RESPONSE: %s', root_tag)
         try:
             version = element.xpath('//@version')[0]
         except Exception as err: