Implement list function in Notification controller.

src/controller/mod.rs

@@ -6,6 +6,6 @@ pub fn route_stage() -> AdHoc {
     return AdHoc::on_ignite("Initializing controller routes...", |rocket| async {
         rocket
             .mount("/", routes![notification::subscribe, notification::unsubscribe,
-                                    notification::receive])
+                                    notification::receive, notification::list])
     });
 }

src/controller/notification.rs

@@ -27,4 +27,12 @@ pub fn receive(notification: Json<Notification>) -> Result<Json<Notification>> {
         Ok(f) => Ok(Json::from(f)),
         Err(e) => Err(e)
     };
+}
+
+#[get("/")]
+pub fn list() -> Result<Json<Vec<String>>> {
+    return match NotificationService::list_messages() {
+        Ok(f) => Ok(Json::from(f)),
+        Err(e) => Err(e)
+    }
 }
\ No newline at end of file