feat(display): implement Display for MessageHubError

Signed-off-by: Riccardo Gallo <[email protected]>

rust/astarte-message-hub-proto/src/proto_message_hub.rs

@@ -25,6 +25,7 @@
 
 use self::{astarte_data_type::Data, astarte_message::Payload};
 use serde::Serialize;
+use std::fmt::{Display, Formatter};
 use uuid::Uuid;
 
 include!("astarteplatform.msghub.rs");
@@ -280,6 +281,13 @@ impl MessageHubEvent {
         })
     }
 
+    pub fn take_error(self) -> Option<MessageHubError> {
+        self.event.and_then(|r| match r {
+            message_hub_event::Event::Message(_) => None,
+            message_hub_event::Event::Error(err) => Some(err),
+        })
+    }
+
     pub fn from_error(error: &dyn std::error::Error) -> Self {
         Self {
             event: Some(message_hub_event::Event::Error(
@@ -317,6 +325,24 @@ impl MessageHubError {
     }
 }
 
+impl Display for MessageHubError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}, source: [", self.description)?;
+
+        let Some((first, remaining)) = self.source.split_first() else {
+            return write!(f, "]");
+        };
+
+        write!(f, "{first}")?;
+        for s in remaining {
+            write!(f, ", {s}")?;
+        }
+        write!(f, "]")?;
+
+        Ok(())
+    }
+}
+
 #[cfg(test)]
 mod test {
     use std::collections::HashMap;