Disallow empty samples

src/main.rs

@@ -114,7 +114,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
                 "1".to_string(),
             ],
         )
-        .into_stream(),
+        .into_stream()
+        .try_filter(|message| {
+            let not_empty = !message.is_empty();
+            async move { not_empty }
+        }),
     )
     .map_err(|e| Box::new(e) as Box<dyn Error>);