added isConnectionOpen to the interface and analysis this during execution

Signed-off-by: Jürgen Eckel <juergen@riddleandcode.com>

monitor/mqtt_monitor.go

@@ -221,7 +221,7 @@ func (mms *MqttMonitor) MonitorActiveParticipants() {
 		log.Println("[app] [Monitor] subscribed to tele/# channels")
 
 		for !mms.IsTerminated() {
-			if !mqttClient.IsConnected() {
+			if !mqttClient.IsConnected() || !mqttClient.IsConnectionOpen() {
 				log.Println("[app] [Monitor] retry establishing a connection")
 				break // Exit inner loop on disconnect
 			}

util/mocks/mqtt.go

@@ -15,6 +15,7 @@ type MockMQTTClient struct {
 	SubscribeFunc        func(topic string, qos byte, callback mqtt.MessageHandler) mqtt.Token
 	UnsubscribeFunc      func(topics ...string) mqtt.Token
 	IsConnectedFunc      func() bool
+	IsConnectionOpenFunc func() bool
 	connected            bool
 	connectedMutex       sync.Mutex
 }
@@ -129,3 +130,10 @@ func (m *MockMQTTClient) IsConnected() bool {
 	m.connectedMutex.Unlock()
 	return connected
 }
+
+func (m *MockMQTTClient) IsConnectionOpen() bool {
+	m.connectedMutex.Lock()
+	connected := m.connected
+	m.connectedMutex.Unlock()
+	return connected
+}

util/mqtt.go

@@ -23,6 +23,7 @@ type MQTTClientI interface {
 	Subscribe(topic string, qos byte, callback mqtt.MessageHandler) mqtt.Token
 	Unsubscribe(topics ...string) mqtt.Token
 	IsConnected() bool
+	IsConnectionOpen() bool
 }
 
 var (