render error message as body

src/service.rs

@@ -57,12 +57,16 @@ where
     fn call(&mut self, req: Self::Request) -> Self::Future {
         match req {
             Ok(r) => Either::A(ok(r)),
-            Err((e, framed)) => Either::B(SendErrorFut {
+            Err((e, framed)) => {
+                let mut resp = e.error_response();
+                resp.set_body(format!("{}", e));
+                Either::B(SendErrorFut {
                     framed: Some(framed),
-                res: Some(Message::Item(e.response_with_message())),
+                    res: Some(resp.into()),
                     err: Some(e),
                     _t: PhantomData,
-            }),
+                })
+            }
         }
     }
 }