controller gates logs and metrics on the hive capability and mirrors the grant

swarm-controller/src/schedules.rs

@@ -503,6 +503,11 @@ impl<T: Serialize> Replaced<T> {
         Self { previous, written }
     }
 
+    /// The value the write replaced, `None` when the key held none.
+    pub(crate) fn previous(&self) -> Option<&T> {
+        self.previous.as_ref()
+    }
+
     /// Put `previous` back, or remove the key if it held none, against the
     /// revision the write made. `Ok(false)` when another write has landed
     /// since: that one is newer than what is being undone and stays.