Add open WebSockets to metrics

httpd/server.go

@@ -3,6 +3,7 @@ package httpd
 
 import (
 	"context"
+	"expvar"
 	"fmt"
 	"net"
 	"net/http"
@@ -36,8 +37,16 @@ var (
 	listener       net.Listener
 	sessionStore   sessions.Store
 	globalShutdown chan bool
+
+	// ExpWebSocketConnectsCurrent tracks the number of open WebSockets
+	ExpWebSocketConnectsCurrent = new(expvar.Int)
 )
 
+func init() {
+	m := expvar.NewMap("http")
+	m.Set("WebSocketConnectsCurrent", ExpWebSocketConnectsCurrent)
+}
+
 // Initialize sets up things for unit tests or the Start() method
 func Initialize(
 	cfg config.WebConfig,

rest/socketv1_controller.go

@@ -143,7 +143,12 @@ func MonitorAllMessagesV1(
 	if err != nil {
 		return err
 	}
-	defer conn.Close()
+	httpd.ExpWebSocketConnectsCurrent.Add(1)
+	defer func() {
+		_ = conn.Close()
+		httpd.ExpWebSocketConnectsCurrent.Add(-1)
+	}()
+
 	log.Tracef("HTTP[%v] Upgraded to websocket", req.RemoteAddr)
 
 	// Create, register listener; then interact with conn

themes/bootstrap/public/metrics.js

@@ -104,6 +104,7 @@ function displayMetrics(data, textStatus, jqXHR) {
   metric('memstatsHeapSys', data.memstats.HeapSys, sizeFilter, true);
   metric('memstatsHeapObjects', data.memstats.HeapObjects, numberFilter, true);
   metric('smtpConnectsCurrent', data.smtp.ConnectsCurrent, numberFilter, true);
+  metric('httpWebSocketConnectsCurrent', data.http.WebSocketConnectsCurrent, numberFilter, true);
 
   // Server-side history
   metric('smtpReceivedTotal', data.smtp.ReceivedTotal, numberFilter, false);

themes/bootstrap/templates/root/status.html

@@ -107,6 +107,12 @@ $(document).ready(
         <div class="col-sm-4"><span id="s-memstatsHeapObjects">.</span></div>
         <div class="col-sm-2 hidden-xs">(10min)</div>
       </div>
+      <div class="row">
+        <div class="col-sm-3 col-xs-7"><b>Open WebSockets:</b></div>
+        <div class="col-sm-3 col-xs-5"><span id="m-httpWebSocketConnectsCurrent">.</span></div>
+        <div class="col-sm-4"><span id="s-httpWebSocketConnectsCurrent">.</span></div>
+        <div class="col-sm-2 hidden-xs">(10min)</div>
+      </div>
     </table>
   </div>
 </div>