1 files changed, 38 insertions, 0 deletions
diff --git a/src/swarm/topology.rs b/src/swarm/topology.rs
index 8e25a2a..c5a02f1 100644
--- a/src/swarm/topology.rs
+++ b/src/swarm/topology.rs
@@ -48,6 +48,44 @@ pub(crate) fn is_full_mesh(state: &AppState) -> bool {
         .is_none_or(|view| view.full_mesh)
 }
 
+/// The current view in numbers, once known.
+#[derive(Debug, Clone, Copy)]
+pub(crate) struct Summary {
+    /// Registered members, us included.
+    pub(crate) members: usize,
+    /// Members other than us not currently judged unreachable.
+    pub(crate) reachable: usize,
+    pub(crate) stable: usize,
+    pub(crate) neighbours: usize,
+    pub(crate) stable_neighbours: usize,
+    pub(crate) full_mesh: bool,
+}
+
+pub(crate) fn summary(state: &AppState) -> Option<Summary> {
+    let local = state.local_id();
+    state
+        .neighbours
+        .read()
+        .unwrap_or_else(|poisoned| poisoned.into_inner())
+        .as_ref()
+        .map(|view| Summary {
+            members: view.members.len(),
+            reachable: view
+                .members
+                .iter()
+                .filter(|m| m.as_str() != local && !view.unreachable.contains(*m))
+                .count(),
+            stable: view.stable.len(),
+            neighbours: view.neighbours.len(),
+            stable_neighbours: view
+                .neighbours
+                .iter()
+                .filter(|m| view.stable.contains(*m))
+                .count(),
+            full_mesh: view.full_mesh,
+        })
+}
+
 /// Whether we initiate contact with `peer`: HELLOs, keepalives, dormancy checks, sync
 /// openings. Everyone is a neighbour until the view is known (while joining, or before
 /// any member registered), so joining works as in a full mesh. We always *answer*