From 1d4079b19884b9b130ac9a6274b96ed04f54720f Mon Sep 17 00:00:00 2001
From: Brian Ginsburg <gins@brianginsburg.com>
Date: Tue, 31 Oct 2023 09:53:54 -0700
Subject: [PATCH] chore: Move event handler connection fields into a substruct

---
 homestar-runtime/src/event_handler.rs         | 26 ++++++++++++-------
 .../src/event_handler/swarm_event.rs          | 17 ++++++------
 2 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/homestar-runtime/src/event_handler.rs b/homestar-runtime/src/event_handler.rs
index c55d03d1f..86f374ec3 100644
--- a/homestar-runtime/src/event_handler.rs
+++ b/homestar-runtime/src/event_handler.rs
@@ -61,8 +61,7 @@ pub(crate) struct EventHandler<DB: Database> {
     sender: Arc<channel::AsyncBoundedChannelSender<Event>>,
     receiver: channel::AsyncBoundedChannelReceiver<Event>,
     query_senders: FnvHashMap<QueryId, (RequestResponseKey, Option<P2PSender>)>,
-    connected_peers: FnvHashMap<PeerId, ConnectedPoint>,
-    connected_peers_limit: u32,
+    connections: Connections,
     request_response_senders: FnvHashMap<RequestId, (RequestResponseKey, P2PSender)>,
     rendezvous: Rendezvous,
     pubsub_enabled: bool,
@@ -85,8 +84,7 @@ pub(crate) struct EventHandler<DB: Database> {
     sender: Arc<channel::AsyncBoundedChannelSender<Event>>,
     receiver: channel::AsyncBoundedChannelReceiver<Event>,
     query_senders: FnvHashMap<QueryId, (RequestResponseKey, Option<P2PSender>)>,
-    connected_peers: FnvHashMap<PeerId, ConnectedPoint>,
-    connected_peers_limit: u32,
+    connections: Connections,
     request_response_senders: FnvHashMap<RequestId, (RequestResponseKey, P2PSender)>,
     rendezvous: Rendezvous,
     pubsub_enabled: bool,
@@ -95,6 +93,7 @@ pub(crate) struct EventHandler<DB: Database> {
     external_address_limit: u32,
 }
 
+/// Rendezvous protocol configurations and state
 struct Rendezvous {
     registration_ttl: Duration,
     discovery_interval: Duration,
@@ -102,6 +101,12 @@ struct Rendezvous {
     cookies: FnvHashMap<PeerId, Cookie>,
 }
 
+// Connected peers configuration and state
+struct Connections {
+    peers: FnvHashMap<PeerId, ConnectedPoint>,
+    max_peers: u32,
+}
+
 impl<DB> EventHandler<DB>
 where
     DB: Database,
@@ -136,8 +141,10 @@ where
             receiver,
             query_senders: FnvHashMap::default(),
             request_response_senders: FnvHashMap::default(),
-            connected_peers: FnvHashMap::default(),
-            connected_peers_limit: settings.network.max_connected_peers,
+            connections: Connections {
+                peers: FnvHashMap::default(),
+                max_peers: settings.network.max_connected_peers,
+            },
             rendezvous: Rendezvous {
                 registration_ttl: settings.network.rendezvous_registration_ttl,
                 discovery_interval: settings.network.rendezvous_discovery_interval,
@@ -167,10 +174,11 @@ where
             sender,
             receiver,
             query_senders: FnvHashMap::default(),
-            connected_peers: FnvHashMap::default(),
-            connected_peers_limit: settings.network.max_connected_peers,
-            discovered_peers: FnvHashMap::default(),
             request_response_senders: FnvHashMap::default(),
+            connected: Connections {
+                peers: FnvHashMap::default(),
+                max_peers: settings.network.max_connected_peers,
+            },
             rendezvous: Rendezvous {
                 registration_ttl: settings.network.rendezvous_registration_ttl,
                 discovery_interval: settings.network.rendezvous_discovery_interval,
diff --git a/homestar-runtime/src/event_handler/swarm_event.rs b/homestar-runtime/src/event_handler/swarm_event.rs
index b957243cc..011317122 100644
--- a/homestar-runtime/src/event_handler/swarm_event.rs
+++ b/homestar-runtime/src/event_handler/swarm_event.rs
@@ -209,10 +209,10 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
                             .cookies
                             .insert(rendezvous_node, cookie);
 
-                        let connected_peers_count = event_handler.connected_peers.len();
+                        let connected_peers_count = event_handler.connections.peers.len();
 
                         // Skip dialing peers if at connected peers limit
-                        if connected_peers_count >= event_handler.connected_peers_limit as usize {
+                        if connected_peers_count >= event_handler.connections.max_peers as usize {
                             warn!("peers discovered through rendezvous not dialed because max connected peers limit reached");
                             return;
                         }
@@ -222,7 +222,8 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
                             .iter()
                             .filter(|registration| {
                                 !event_handler
-                                    .connected_peers
+                                    .connections
+                                    .peers
                                     .contains_key(&registration.record.peer_id())
                             })
                             .collect();
@@ -235,7 +236,7 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
                             // Dial discovered peer if not us and not at connected peers limit
                             if !self_registration
                                 && connected_peers_count + index
-                                    < event_handler.connected_peers_limit as usize
+                                    < event_handler.connections.max_peers as usize
                             {
                                 let peer_id = registration.record.peer_id();
                                 let opts = DialOpts::peer_id(peer_id)
@@ -672,8 +673,8 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
                     "mDNS discovered a new peer"
                 );
 
-                if event_handler.connected_peers.len()
-                    < event_handler.connected_peers_limit as usize
+                if event_handler.connections.peers.len()
+                    < event_handler.connections.max_peers as usize
                 {
                     let _ = event_handler.swarm.dial(
                         DialOpts::peer_id(peer_id)
@@ -720,14 +721,14 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
         } => {
             debug!(peer_id=peer_id.to_string(), endpoint=?endpoint, "peer connection established");
             // add peer to connected peers list
-            event_handler.connected_peers.insert(peer_id, endpoint);
+            event_handler.connections.peers.insert(peer_id, endpoint);
         }
         SwarmEvent::ConnectionClosed { peer_id, cause, .. } => {
             debug!(
                 peer_id = peer_id.to_string(),
                 "peer connection closed, cause: {cause:?}"
             );
-            event_handler.connected_peers.remove_entry(&peer_id);
+            event_handler.connections.peers.remove_entry(&peer_id);
 
             // Remove peer from DHT if not in configured peers
             if event_handler.node_addresses.iter().all(|multiaddr| {