handle empty node list before finding disconnected ip

src/datastore.rs

@@ -214,7 +214,10 @@ impl State {
 
         let conn_ips = self.get_connected_ips().await;
         let nodes = self.nodes.read().await;
-        let skip = OsRng.next_u64().try_into().unwrap_or(0) % nodes.len();
+        if nodes.is_empty() {
+            return None;
+        }
+        let skip = OsRng.next_u64() as usize % nodes.len();
         nodes
             .keys()
             .map(|ip| ip.to_string())