take last seen into account - prevent mass delete if tor shutdown

comms/src/connectivity/config.rs

@@ -41,6 +41,10 @@ pub struct ConnectivityConfig {
     /// The length of time to wait before disconnecting a connection that failed tie breaking.
     /// Default: 1s
     pub connection_tie_break_linger: Duration,
+    /// If the peer has not been seen within this interval, it will be removed from the peer list on the
+    /// next connection attempt.
+    /// Default: 24 hours
+    pub expire_peer_last_seen_duration: Duration,
 }
 
 impl Default for ConnectivityConfig {
@@ -52,6 +56,7 @@ impl Default for ConnectivityConfig {
             is_connection_reaping_enabled: true,
             max_failures_mark_offline: 2,
             connection_tie_break_linger: Duration::from_secs(2),
+            expire_peer_last_seen_duration: Duration::from_secs(24 * 60 * 60),
         }
     }
 }

comms/src/connectivity/manager.rs

@@ -437,8 +437,17 @@ impl ConnectivityManagerActor {
                 target: LOG_TARGET,
                 "Peer `{}` was marked as offline after {} attempts. Removing peer from peer list", num_failed, node_id
             );
-            self.peer_manager.delete_peer(node_id).await?;
+
             self.connection_stats.remove(node_id);
+            if let Ok(peer) = self.peer_manager.find_by_node_id(node_id).await {
+                if peer
+                    .last_seen_since()
+                    .map(|t| t > self.config.expire_peer_last_seen_duration)
+                    .unwrap_or(true)
+                {
+                    self.peer_manager.delete_peer(node_id).await?;
+                }
+            }
         }
 
         Ok(())

comms/src/peer_manager/peer.rs

@@ -210,6 +210,12 @@ impl Peer {
         self.addresses.last_seen()
     }
 
+    /// Provides that length of time since the last successful interaction with the peer
+    pub fn last_seen_since(&self) -> Option<Duration> {
+        self.last_seen()
+            .and_then(|dt| Utc::now().signed_duration_since(dt).to_std().ok())
+    }
+
     /// Returns true if this peer has the given feature, otherwise false
     pub fn has_features(&self, features: PeerFeatures) -> bool {
         self.features.contains(features)