From 4f4f4eb0d6f64c38b6a237351efed30df598c9bb Mon Sep 17 00:00:00 2001
From: onur-ozkan <work@onurozkan.dev>
Date: Tue, 24 Sep 2024 10:01:09 +0300
Subject: [PATCH] extend configuration interface with
 `peer_healthcheck_caching_secs`

Signed-off-by: onur-ozkan <work@onurozkan.dev>
---
 src/ctx.rs            | 16 +++++++++++++++-
 src/proxy/http/mod.rs |  5 +++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/src/ctx.rs b/src/ctx.rs
index 5eb24ef..2a48dd2 100644
--- a/src/ctx.rs
+++ b/src/ctx.rs
@@ -9,6 +9,11 @@ pub(crate) use super::*;
 
 const DEFAULT_TOKEN_EXPIRATION_TIME: i64 = 3600;
 pub(crate) const DEFAULT_PORT: u16 = 5000;
+
+const fn default_peer_caching_secs() -> u64 {
+    10
+}
+
 static CONFIG: OnceCell<AppConfig> = OnceCell::new();
 
 pub(crate) fn get_app_config() -> &'static AppConfig {
@@ -58,6 +63,13 @@ pub(crate) struct AppConfig {
     pub(crate) proxy_routes: Vec<ProxyRoute>,
     /// The default rate limiting rules for maintaining the frequency of incoming traffic for per client.
     pub(crate) rate_limiter: RateLimiter,
+    /// The number of seconds to cache a known peer.
+    ///
+    /// When a peer is identified as connected with `peer_connection_healthcheck` RPC,
+    /// this value determines how long to cache that peer as known-peer to avoid
+    /// sending repeated `peer_connection_healthcheck` requests for every proxy request.
+    #[serde(default = "default_peer_caching_secs")]
+    pub(crate) peer_healthcheck_caching_secs: u64,
 }
 
 /// Defines a routing rule for proxying requests from an inbound route to an outbound URL
@@ -203,6 +215,7 @@ pub(crate) fn get_app_config_test_instance() -> AppConfig {
             rp_30_min: 555,
             rp_60_min: 555,
         },
+        peer_healthcheck_caching_secs: 10,
     }
 }
 
@@ -282,7 +295,8 @@ fn test_app_config_serialzation_and_deserialization() {
             "rp_15_min": 555,
             "rp_30_min": 555,
             "rp_60_min": 555
-        }
+        },
+        "peer_healthcheck_caching_secs": 10,
     });
 
     let actual_config: AppConfig = serde_json::from_str(&json_config.to_string()).unwrap();
diff --git a/src/proxy/http/mod.rs b/src/proxy/http/mod.rs
index ca4e17d..4dcdff6 100644
--- a/src/proxy/http/mod.rs
+++ b/src/proxy/http/mod.rs
@@ -104,7 +104,8 @@ async fn peer_connection_healthcheck(
 ) -> Result<(), StatusCode> {
     // Once we know a peer is connected to the KDF network, we can assume they are connected
     // for 10 seconds without asking again.
-    const KNOW_PEER_EXPIRATION: Duration = Duration::from_secs(10);
+    let know_peer_expiration = Duration::from_secs(cfg.peer_healthcheck_caching_secs);
+
     static KNOWN_PEERS: LazyLock<Mutex<ExpirableMap<String, ()>>> =
         LazyLock::new(|| Mutex::new(ExpirableMap::new()));
 
@@ -117,7 +118,7 @@ async fn peer_connection_healthcheck(
         match peer_connection_healthcheck_rpc(cfg, &signed_message.address).await {
             Ok(response) => {
                 if response["result"] == serde_json::json!(true) {
-                    know_peers.insert(signed_message.address.clone(), (), KNOW_PEER_EXPIRATION);
+                    know_peers.insert(signed_message.address.clone(), (), know_peer_expiration);
                 } else {
                     tracked_log(
                         log::Level::Warn,