Feature/max retry (#409)

* Maximum number of allowed reconnection attempts

* Requiring initial internode connection to be successful

* Decreased logging level for failing to establish initial connection

mixnode/src/config/mod.rs

@@ -40,6 +40,7 @@ const DEFAULT_PACKET_FORWARDING_INITIAL_BACKOFF: Duration = Duration::from_milli
 const DEFAULT_PACKET_FORWARDING_MAXIMUM_BACKOFF: Duration = Duration::from_millis(300_000);
 const DEFAULT_INITIAL_CONNECTION_TIMEOUT: Duration = Duration::from_millis(1_500);
 const DEFAULT_CACHE_ENTRY_TTL: Duration = Duration::from_millis(30_000);
+const DEFAULT_MAXIMUM_RECONNECTION_ATTEMPTS: u32 = 20;
 
 #[derive(Debug, Default, Deserialize, PartialEq, Serialize)]
 #[serde(deny_unknown_fields)]
@@ -330,6 +331,10 @@ impl Config {
         self.debug.initial_connection_timeout
     }
 
+    pub fn get_packet_forwarding_max_reconnections(&self) -> u32 {
+        self.debug.maximum_reconnection_attempts
+    }
+
     pub fn get_cache_entry_ttl(&self) -> Duration {
         self.debug.cache_entry_ttl
     }
@@ -490,6 +495,10 @@ pub struct Debug {
     )]
     initial_connection_timeout: Duration,
 
+    /// Maximum number of retries node is going to attempt to re-establish existing connection
+    /// to another node when forwarding sphinx packets.
+    maximum_reconnection_attempts: u32,
+
     /// Duration for which a cached vpn processing result is going to get stored for.
     #[serde(
         deserialize_with = "deserialize_duration",
@@ -505,6 +514,7 @@ impl Default for Debug {
             packet_forwarding_initial_backoff: DEFAULT_PACKET_FORWARDING_INITIAL_BACKOFF,
             packet_forwarding_maximum_backoff: DEFAULT_PACKET_FORWARDING_MAXIMUM_BACKOFF,
             initial_connection_timeout: DEFAULT_INITIAL_CONNECTION_TIMEOUT,
+            maximum_reconnection_attempts: DEFAULT_MAXIMUM_RECONNECTION_ATTEMPTS,
             cache_entry_ttl: DEFAULT_CACHE_ENTRY_TTL,
         }
     }

mixnode/src/node/mod.rs

@@ -83,6 +83,7 @@ impl MixNode {
             self.config.get_packet_forwarding_initial_backoff(),
             self.config.get_packet_forwarding_maximum_backoff(),
             self.config.get_initial_connection_timeout(),
+            self.config.get_packet_forwarding_max_reconnections(),
         );
 
         tokio::spawn(async move { packet_forwarder.run().await });