Add MQTT authentication support

Author: Stas Turlo

platforms/mqtt/mqtt_adaptor.go

@@ -11,6 +11,8 @@ type MqttAdaptor struct {
 	name     string
 	Host     string
 	clientID string
+	username string
+	password string
 	client   *mqtt.Client
 }
 
@@ -22,11 +24,22 @@ func NewMqttAdaptor(name string, host string, clientID string) *MqttAdaptor {
 		clientID: clientID,
 	}
 }
+
+func NewMqttAdaptorWithAuth(name, host, clientID, username, password string) *MqttAdaptor {
+	return &MqttAdaptor{
+		name:     name,
+		Host:     host,
+		clientID: clientID,
+		username: username,
+		password: password,
+	}
+}
+
 func (a *MqttAdaptor) Name() string { return a.name }
 
 // Connect returns true if connection to mqtt is established
 func (a *MqttAdaptor) Connect() (errs []error) {
-	a.client = mqtt.NewClient(createClientOptions(a.clientID, a.Host))
+	a.client = mqtt.NewClient(createClientOptions(a.clientID, a.Host, a.username, a.password))
 	if token := a.client.Connect(); token.Wait() && token.Error() != nil {
 		errs = append(errs, token.Error())
 	}
@@ -68,10 +81,14 @@ func (a *MqttAdaptor) On(event string, f func(s []byte)) bool {
 	return true
 }
 
-func createClientOptions(clientId, raw string) *mqtt.ClientOptions {
+func createClientOptions(clientId, raw, username, password string) *mqtt.ClientOptions {
 	opts := mqtt.NewClientOptions()
 	opts.AddBroker(raw)
 	opts.SetClientID(clientId)
+	if username != "" && password != "" {
+		opts.SetPassword(password)
+		opts.SetUsername(username)
+	}
 	opts.AutoReconnect = false
 	return opts
 }