[FIX] mig-users_ldap_groups: safe LDAP decode

The group mapping in query mode fails if LDAP returns binary data in any
of the fields. This adds a function that handles such situation by
base64 encoding it.

users_ldap_groups/models/res_company_ldap_operator.py

@@ -32,10 +32,17 @@ def equals(self, ldap_entry, mapping):
 
     def query(self, ldap_entry, mapping):
         query_string = Template(mapping.value).safe_substitute(
-            {attr: ldap_entry[1][attr][0].decode() for attr in ldap_entry[1]}
+            {attr: self.safe_ldap_decode(ldap_entry[1][attr][0]) for attr in ldap_entry[1]}
         )
 
         results = mapping.ldap_id._query(mapping.ldap_id.read()[0], query_string)
         _logger.debug('Performed LDAP query "%s" results: %s', query_string, results)
 
         return bool(results)
+
+    def safe_ldap_decode(self, attr):
+        import base64
+        try:
+            return attr.decode()
+        except:
+            return base64.b64encode(attr)