start refactor of ip management

src/api/error.rs

@@ -1,9 +1,9 @@
 use derive_more::{Display, Error};
 
-impl actix_web::error::ResponseError for ReturnedError{}
+impl actix_web::error::ResponseError for ReturnedError {}
 
 #[derive(Debug, Display, Error)]
-#[display(fmt = "my error: {}", name)]
+#[display("my error: {}", name)]
 pub struct ReturnedError {
     pub name: String,
 }