start handling topic health event

examples/basic/src/main.rs

@@ -40,6 +40,7 @@ async fn main() -> Result<(), Error> {
                         println!("Message Received in NODE 2: {}", msg);
                         println!("::::::::::::::::::::::::::::::::::::::::::::::::::::");
                     }
+                    WakuEvent::RelayTopicHealthChange(_evt) => {} // do nothing
                     WakuEvent::Unrecognized(err) => panic!("Unrecognized waku event: {:?}", err),
                     _ => panic!("event case not expected"),
                 };

examples/tic-tac-toe-gui/src/main.rs

@@ -74,7 +74,8 @@ impl TicTacToeApp<Initialized> {
                                 // Handle the error as needed, or just log and skip
                             }
                         }
-                    }
+                    },
+                    WakuEvent::RelayTopicHealthChange(_evt) => {}, // do nothing
                     WakuEvent::Unrecognized(err) => panic!("Unrecognized waku event: {:?}", err),
                     _ => panic!("event case not expected"),
                 };

examples/toy-chat/src/main.rs

@@ -110,7 +110,8 @@ impl App<Initialized> {
                                 write!(out, "{e:?}").unwrap();
                             }
                         }
-                    }
+                    },
+                    WakuEvent::RelayTopicHealthChange(_evt) => {} // do nothing
                     WakuEvent::Unrecognized(err) => eprintln!("Unrecognized waku event: {:?}", err),
                     _ => eprintln!("event case not expected"),
                 };

waku-bindings/src/node/events.rs

@@ -20,6 +20,10 @@ use crate::MessageHash;
 pub enum WakuEvent {
     #[serde(rename = "message")]
     WakuMessage(WakuMessageEvent),
+
+    #[serde(rename = "relay_topic_health_change")]
+    RelayTopicHealthChange(TopicHealthEvent),
+
     Unrecognized(serde_json::Value),
 }
 
@@ -35,9 +39,20 @@ pub struct WakuMessageEvent {
     pub waku_message: WakuMessage,
 }
 
+/// Type of `event` field for a `message` event
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct TopicHealthEvent {
+    /// The pubsub topic on which the message was received
+    pub pubsub_topic: String,
+    /// The message hash
+    pub topic_health: String,
+}
+
 #[cfg(test)]
 mod tests {
     use crate::WakuEvent;
+    use crate::WakuEvent::RelayTopicHealthChange;
 
     #[test]
     fn deserialize_message_event() {
@@ -45,4 +60,17 @@ mod tests {
         let evt: WakuEvent = serde_json::from_str(s).unwrap();
         assert!(matches!(evt, WakuEvent::WakuMessage(_)));
     }
+
+    #[test]
+    fn deserialize_topic_health_change_event() {
+        let s = "{\"eventType\":\"relay_topic_health_change\", \"pubsubTopic\":\"/waku/2/rs/16/1\",\"topicHealth\":\"MinimallyHealthy\"}";
+        let evt: WakuEvent = serde_json::from_str(s).unwrap();
+        match evt {
+            RelayTopicHealthChange(topic_health_event) => {
+                assert_eq!(topic_health_event.pubsub_topic, "/waku/2/rs/16/1");
+                assert_eq!(topic_health_event.topic_health, "MinimallyHealthy");
+            }
+            _ => panic!("Expected RelayTopicHealthChange event, but got {:?}", evt),
+        }
+    }
 }