feat(metrics): implement custom relay client metrics

ant-networking/src/event/swarm.rs

@@ -55,6 +55,10 @@ impl SwarmDriver {
                 self.handle_kad_event(kad_event)?;
             }
             SwarmEvent::Behaviour(NodeEvent::RelayClient(event)) => {
+                #[cfg(feature = "open-metrics")]
+                if let Some(metrics_recorder) = &self.metrics_recorder {
+                    metrics_recorder.record(&(*event));
+                }
                 event_string = "relay_client_event";
 
                 info!(?event, "relay client event");

ant-networking/src/metrics/mod.rs

@@ -8,6 +8,7 @@
 
 // Implementation to record `libp2p::upnp::Event` metrics
 mod bad_node;
+mod relay_client;
 pub mod service;
 #[cfg(feature = "upnp")]
 mod upnp;
@@ -39,6 +40,7 @@ pub(crate) struct NetworkMetricsRecorder {
     libp2p_metrics: Libp2pMetrics,
     #[cfg(feature = "upnp")]
     upnp_events: Family<upnp::UpnpEventLabels, Counter>,
+    relay_client_events: Family<relay_client::RelayClientEventLabels, Counter>,
 
     // metrics from ant-networking
     pub(crate) connected_peers: Gauge,
@@ -136,6 +138,13 @@ impl NetworkMetricsRecorder {
             upnp_events.clone(),
         );
 
+        let relay_client_events = Family::default();
+        sub_registry.register(
+            "relay_client_events",
+            "Events emitted by the relay client",
+            relay_client_events.clone(),
+        );
+
         let process_memory_used_mb = Gauge::<f64, AtomicU64>::default();
         sub_registry.register(
             "process_memory_used_mb",
@@ -211,6 +220,7 @@ impl NetworkMetricsRecorder {
             libp2p_metrics,
             #[cfg(feature = "upnp")]
             upnp_events,
+            relay_client_events,
 
             records_stored,
             estimated_network_size,

ant-networking/src/metrics/relay_client.rs

@@ -0,0 +1,47 @@
+// Copyright 2024 MaidSafe.net limited.
+//
+// This SAFE Network Software is licensed to you under The General Public License (GPL), version 3.
+// Unless required by applicable law or agreed to in writing, the SAFE Network Software distributed
+// under the GPL Licence is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. Please review the Licences for the specific language governing
+// permissions and limitations relating to use of the SAFE Network Software.
+
+use prometheus_client::encoding::{EncodeLabelSet, EncodeLabelValue};
+
+#[derive(Debug, Clone, Hash, PartialEq, Eq, EncodeLabelSet)]
+pub(crate) struct RelayClientEventLabels {
+    event: EventType,
+}
+
+#[derive(Debug, Clone, Hash, PartialEq, Eq, EncodeLabelValue)]
+enum EventType {
+    ReservationReqAccepted,
+    OutboundCircuitEstablished,
+    InboundCircuitEstablished,
+}
+
+impl From<&libp2p::relay::client::Event> for EventType {
+    fn from(event: &libp2p::relay::client::Event) -> Self {
+        match event {
+            libp2p::relay::client::Event::ReservationReqAccepted { .. } => {
+                EventType::ReservationReqAccepted
+            }
+            libp2p::relay::client::Event::OutboundCircuitEstablished { .. } => {
+                EventType::OutboundCircuitEstablished
+            }
+            libp2p::relay::client::Event::InboundCircuitEstablished { .. } => {
+                EventType::InboundCircuitEstablished
+            }
+        }
+    }
+}
+
+impl super::Recorder<libp2p::relay::client::Event> for super::NetworkMetricsRecorder {
+    fn record(&self, event: &libp2p::relay::client::Event) {
+        self.relay_client_events
+            .get_or_create(&RelayClientEventLabels {
+                event: event.into(),
+            })
+            .inc();
+    }
+}