add direction information to PeerInfo (#1768)

## Issue Addressed

NA

## Proposed Changes

Adds a direction field to `PeerConnectionStatus` that can be accessed by calling `is_outgoing` which will return `true` iff the peer is connected and the first connection was an outgoing one.

beacon_node/eth2_libp2p/src/peer_manager/peer_info.rs

@@ -43,6 +43,9 @@ pub struct PeerInfo<T: EthSpec> {
     pub min_ttl: Option<Instant>,
     /// Is the peer a trusted peer.
     pub is_trusted: bool,
+    /// Direction of the first connection of the last (or current) connected session with this peer.
+    /// None if this peer was never connected.
+    pub connection_direction: Option<ConnectionDirection>,
 }
 
 impl<TSpec: EthSpec> Default for PeerInfo<TSpec> {
@@ -58,6 +61,7 @@ impl<TSpec: EthSpec> Default for PeerInfo<TSpec> {
             meta_data: None,
             min_ttl: None,
             is_trusted: false,
+            connection_direction: None,
         }
     }
 }
@@ -112,6 +116,30 @@ impl<T: EthSpec> PeerInfo<T> {
         }
     }
 
+    /// Modifies the status to Connected and increases the number of ingoing
+    /// connections by one
+    pub(crate) fn connect_ingoing(&mut self) {
+        match &mut self.connection_status {
+            Connected { n_in, .. } => *n_in += 1,
+            Disconnected { .. } | Banned { .. } | Dialing { .. } | Unknown => {
+                self.connection_status = Connected { n_in: 1, n_out: 0 };
+                self.connection_direction = Some(ConnectionDirection::Incoming);
+            }
+        }
+    }
+
+    /// Modifies the status to Connected and increases the number of outgoing
+    /// connections by one
+    pub(crate) fn connect_outgoing(&mut self) {
+        match &mut self.connection_status {
+            Connected { n_out, .. } => *n_out += 1,
+            Disconnected { .. } | Banned { .. } | Dialing { .. } | Unknown => {
+                self.connection_status = Connected { n_in: 0, n_out: 1 };
+                self.connection_direction = Some(ConnectionDirection::Outgoing);
+            }
+        }
+    }
+
     #[cfg(test)]
     /// Add an f64 to a non-trusted peer's score abiding by the limits.
     pub fn add_to_score(&mut self, score: f64) {
@@ -136,6 +164,13 @@ impl Default for PeerStatus {
     }
 }
 
+/// Connection Direction of connection.
+#[derive(Debug, Clone, Serialize)]
+pub enum ConnectionDirection {
+    Incoming,
+    Outgoing,
+}
+
 /// Connection Status of the peer.
 #[derive(Debug, Clone)]
 pub enum PeerConnectionStatus {
@@ -251,28 +286,6 @@ impl PeerConnectionStatus {
         matches!(self, Disconnected { .. })
     }
 
-    /// Modifies the status to Connected and increases the number of ingoing
-    /// connections by one
-    pub fn connect_ingoing(&mut self) {
-        match self {
-            Connected { n_in, .. } => *n_in += 1,
-            Disconnected { .. } | Banned { .. } | Dialing { .. } | Unknown => {
-                *self = Connected { n_in: 1, n_out: 0 }
-            }
-        }
-    }
-
-    /// Modifies the status to Connected and increases the number of outgoing
-    /// connections by one
-    pub fn connect_outgoing(&mut self) {
-        match self {
-            Connected { n_out, .. } => *n_out += 1,
-            Disconnected { .. } | Banned { .. } | Dialing { .. } | Unknown => {
-                *self = Connected { n_in: 0, n_out: 1 }
-            }
-        }
-    }
-
     /// Modifies the status to Disconnected and sets the last seen instant to now
     pub fn disconnect(&mut self) {
         *self = Disconnected {

beacon_node/eth2_libp2p/src/peer_manager/peerdb.rs

@@ -365,7 +365,7 @@ impl<TSpec: EthSpec> PeerDB<TSpec> {
         }
         self.banned_peers_count
             .remove_banned_peer(&info.connection_status);
-        info.connection_status.connect_ingoing();
+        info.connect_ingoing();
 
         // Add the seen ip address to the peer's info
         if let Some(ip_addr) = multiaddr.iter().find_map(|p| match p {
@@ -386,7 +386,7 @@ impl<TSpec: EthSpec> PeerDB<TSpec> {
         }
         self.banned_peers_count
             .remove_banned_peer(&info.connection_status);
-        info.connection_status.connect_outgoing();
+        info.connect_outgoing();
 
         // Add the seen ip address to the peer's info
         if let Some(ip_addr) = multiaddr.iter().find_map(|p| match p {