Add ZMQ communication statistics tracking and display

Cargo.lock

@@ -279,7 +279,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.184"
+version = "0.1.185"
 dependencies = [
  "anyhow",
  "chrono",
@@ -301,7 +301,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.184"
+version = "0.1.185"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -324,7 +324,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.184"
+version = "0.1.185"
 dependencies = [
  "chrono",
  "serde",

agent/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard-agent"
-version = "0.1.185"
+version = "0.1.186"
 edition = "2021"
 
 [dependencies]

dashboard/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard"
-version = "0.1.185"
+version = "0.1.186"
 edition = "2021"
 
 [dependencies]

dashboard/src/app.rs

@@ -215,7 +215,7 @@ impl Dashboard {
 
                     // Update TUI with new metrics (only if not headless)
                     if let Some(ref mut tui_app) = self.tui_app {
-                        tui_app.update_metrics(&self.metric_store);
+                        tui_app.update_metrics(&mut self.metric_store);
                     }
                 }
                 

dashboard/src/metrics/store.rs

@@ -5,6 +5,14 @@ use tracing::{debug, info, warn};
 
 use super::MetricDataPoint;
 
+/// ZMQ communication statistics per host
+#[derive(Debug, Clone)]
+pub struct ZmqStats {
+    pub packets_received: u64,
+    pub last_packet_time: Instant,
+    pub last_packet_age_secs: f64,
+}
+
 /// Central metric storage for the dashboard
 pub struct MetricStore {
     /// Current structured data: hostname -> AgentData
@@ -13,6 +21,8 @@ pub struct MetricStore {
     historical_metrics: HashMap<String, Vec<MetricDataPoint>>,
     /// Last heartbeat timestamp per host
     last_heartbeat: HashMap<String, Instant>,
+    /// ZMQ communication statistics per host
+    zmq_stats: HashMap<String, ZmqStats>,
     /// Configuration
     max_metrics_per_host: usize,
     history_retention: Duration,
@@ -24,6 +34,7 @@ impl MetricStore {
             current_agent_data: HashMap::new(),
             historical_metrics: HashMap::new(),
             last_heartbeat: HashMap::new(),
+            zmq_stats: HashMap::new(),
             max_metrics_per_host,
             history_retention: Duration::from_secs(history_retention_hours * 3600),
         }
@@ -44,6 +55,16 @@ impl MetricStore {
         self.last_heartbeat.insert(hostname.clone(), now);
         debug!("Updated heartbeat for host {}", hostname);
 
+        // Update ZMQ stats
+        let stats = self.zmq_stats.entry(hostname.clone()).or_insert(ZmqStats {
+            packets_received: 0,
+            last_packet_time: now,
+            last_packet_age_secs: 0.0,
+        });
+        stats.packets_received += 1;
+        stats.last_packet_time = now;
+        stats.last_packet_age_secs = 0.0; // Just received
+
         // Add to history
         let host_history = self
             .historical_metrics
@@ -65,6 +86,15 @@ impl MetricStore {
         self.current_agent_data.get(hostname)
     }
 
+    /// Get ZMQ communication statistics for a host
+    pub fn get_zmq_stats(&mut self, hostname: &str) -> Option<ZmqStats> {
+        let now = Instant::now();
+        self.zmq_stats.get_mut(hostname).map(|stats| {
+            // Update packet age
+            stats.last_packet_age_secs = now.duration_since(stats.last_packet_time).as_secs_f64();
+            stats.clone()
+        })
+    }
 
     /// Get connected hosts (hosts with recent heartbeats)
     pub fn get_connected_hosts(&self, timeout: Duration) -> Vec<String> {

dashboard/src/ui/mod.rs

@@ -100,7 +100,7 @@ impl TuiApp {
     }
 
     /// Update widgets with structured data from store (only for current host)
-    pub fn update_metrics(&mut self, metric_store: &MetricStore) {
+    pub fn update_metrics(&mut self, metric_store: &mut MetricStore) {
         if let Some(hostname) = self.current_host.clone() {
             // Get structured data for this host
             if let Some(agent_data) = metric_store.get_agent_data(&hostname) {
@@ -110,6 +110,14 @@ impl TuiApp {
                 host_widgets.system_widget.update_from_agent_data(agent_data);
                 host_widgets.services_widget.update_from_agent_data(agent_data);
 
+                // Update ZMQ stats
+                if let Some(zmq_stats) = metric_store.get_zmq_stats(&hostname) {
+                    host_widgets.system_widget.update_zmq_stats(
+                        zmq_stats.packets_received,
+                        zmq_stats.last_packet_age_secs
+                    );
+                }
+
                 host_widgets.last_update = Some(Instant::now());
             }
         }

dashboard/src/ui/widgets/system.rs

@@ -15,6 +15,10 @@ pub struct SystemWidget {
     nixos_build: Option<String>,
     agent_hash: Option<String>,
 
+    // ZMQ communication stats
+    zmq_packets_received: Option<u64>,
+    zmq_last_packet_age: Option<f64>,
+
     // Network interfaces
     network_interfaces: Vec<cm_dashboard_shared::NetworkInterfaceData>,
 
@@ -92,6 +96,8 @@ impl SystemWidget {
         Self {
             nixos_build: None,
             agent_hash: None,
+            zmq_packets_received: None,
+            zmq_last_packet_age: None,
             network_interfaces: Vec::new(),
             cpu_load_1min: None,
             cpu_load_5min: None,
@@ -154,6 +160,12 @@ impl SystemWidget {
     pub fn _get_agent_hash(&self) -> Option<&String> {
         self.agent_hash.as_ref()
     }
+
+    /// Update ZMQ communication statistics
+    pub fn update_zmq_stats(&mut self, packets_received: u64, last_packet_age_secs: f64) {
+        self.zmq_packets_received = Some(packets_received);
+        self.zmq_last_packet_age = Some(last_packet_age_secs);
+    }
 }
 
 use super::Widget;
@@ -796,6 +808,18 @@ impl SystemWidget {
             Span::styled(format!("Agent: {}", agent_version_text), Typography::secondary())
         ]));
 
+        // ZMQ communication stats
+        if let (Some(packets), Some(age)) = (self.zmq_packets_received, self.zmq_last_packet_age) {
+            let age_text = if age < 1.0 {
+                format!("{:.0}ms ago", age * 1000.0)
+            } else {
+                format!("{:.1}s ago", age)
+            };
+            lines.push(Line::from(vec![
+                Span::styled(format!("ZMQ: {} pkts, last {}", packets, age_text), Typography::secondary())
+            ]));
+        }
+
         // CPU section
         lines.push(Line::from(vec![
             Span::styled("CPU:", Typography::widget_title())

shared/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard-shared"
-version = "0.1.185"
+version = "0.1.186"
 edition = "2021"
 
 [dependencies]