Added logs when ws connections is opened and closed (#19)

substrate/client/rpc-servers/src/middleware/metrics.rs

@@ -136,13 +136,37 @@ impl RpcMetrics {
 
 	pub(crate) fn ws_connect(&self) {
 		self.ws_sessions_opened.as_ref().map(|counter| counter.inc());
+		if let Some(ws_sessions_opened) = &self.ws_sessions_opened {
+			if let Some(ws_sessions_closed) = &self.ws_sessions_closed {
+				let active_connections = ws_sessions_opened.get() - ws_sessions_closed.get();
+				log::info!(
+					target: "rpc_metrics",
+					"{{ \"wsSessionsOpened\": {:?}, \"activeConnections\": {:?} }}",
+					ws_sessions_opened.get(),
+					active_connections
+				);
+			}
+		}
+
 	}
 
 	pub(crate) fn ws_disconnect(&self, now: Instant) {
 		let micros = now.elapsed().as_secs();
 
 		self.ws_sessions_closed.as_ref().map(|counter| counter.inc());
 		self.ws_sessions_time.with_label_values(&["ws"]).observe(micros as _);
+
+		if let Some(ws_sessions_closed) = &self.ws_sessions_closed {
+			if let Some(ws_sessions_opened) = &self.ws_sessions_opened {
+				let active_connections = ws_sessions_opened.get() - ws_sessions_closed.get();
+				log::info!(
+					target: "rpc_metrics",
+					"{{ \"wsSessionsClosed\": {:?}, \"activeConnections\": {:?} }}",
+					ws_sessions_closed.get(),
+					active_connections
+				);
+			}
+		}
 	}
 }