refactor for boolean blindness

src/Lib/Error.hs

@@ -55,3 +55,8 @@ handleS9ErrNuclear :: MonadIO m => S9ErrT m a -> m a
 handleS9ErrNuclear action = runExceptT action >>= \case
     Left e -> throwIO e
     Right a -> pure a
+
+errOnNothing :: MonadHandler m => Status -> Text -> Maybe a -> m a 
+errOnNothing status res entity = case entity of
+    Nothing -> sendResponseStatus status res
+    Just a -> pure a