Merge pull request #1289 from GSA/notify-api-1215

fix log formatting

notifications_utils/logging.py

@@ -160,6 +160,12 @@ class JSONFormatter(BaseJSONFormatter):
         log_record["logType"] = "application"
         try:
             log_record["message"] = log_record["message"].format(**log_record)
-        except (KeyError, IndexError) as e:
-            logger.exception("failed to format log message: {} not found".format(e))
+        except KeyError as e:
+            # We get occasional log messages that are nested dictionaries,
+            # for example, delivery receipts, where the formatting fails
+            # This is not a huge problem, don't dump stack traces into the logs
+            # for it.
+            logger.warning(f"failed to format log message: {e}")
+        except IndexError as e:
+            logger.exception(f"failed to format log message: {e}")
         return log_record