Better saml_attribute handling in backend

Author: peppelinux

djangosaml2/backends.py

@@ -95,11 +95,13 @@ def _get_attribute_value(self, django_field: str, attributes: dict, attribute_ma
         for saml_attr, django_fields in attribute_mapping.items():
             if django_field in django_fields and saml_attr in attributes:
                 saml_attribute = attributes.get(saml_attr, [None])
-                if not saml_attribute or not saml_attribute[0]:
-                    logger.error('attributes[saml_attr] attribute '
-                                 'value is missing. Probably the user '
-                                 'session is expired.')
-        return saml_attribute[0]
+
+        if saml_attribute:
+            return saml_attribute[0]
+        else:
+            logger.error('attributes[saml_attr] attribute '
+                         'value is missing. Probably the user '
+                         'session is expired.')
 
     def authenticate(self, request, session_info=None, attribute_mapping=None, create_unknown_user=True, **kwargs):
         if session_info is None or attribute_mapping is None: