Add `Retain` attribute to MQTTMessage

This allows the sending part of the code to decide about the retain
flag. The MQTT go routine will set it accordingly.

2 files changed, 4 insertions, 1 deletions

diff --git a/cache.go b/cache.go
index 4e0eddc..18ce0c9 100644
--- a/cache.go
+++ b/cache.go
@@ -43,6 +43,7 @@ func (c *Cache) Update(states States) {
 			c.Tx <- MQTTMessage{
 				Topic: topic,
 				Payload: payload,
+				Retain: true,
 			}
 		}
 		c.States[id] = state
diff --git a/mqtt.go b/mqtt.go
index fd1cba1..acd0108 100644
--- a/mqtt.go
+++ b/mqtt.go
@@ -27,6 +27,7 @@ var (
 type MQTTMessage struct {
 	Topic   string
 	Payload []byte
+	Retain  bool
 }
 
 type Route struct {
@@ -60,6 +61,7 @@ func MQTTRun(config MQTTConfig, tx chan MQTTMessage, routes ...Route) {
 				message := MQTTMessage{
 					Topic: strings.TrimPrefix(msg.Topic(), config.TopicPrefix + "/"),
 					Payload: msg.Payload(),
+					Retain: msg.Retained(),
 				}
 				route.Destination <- message
 			})
@@ -88,7 +90,7 @@ func MQTTRun(config MQTTConfig, tx chan MQTTMessage, routes ...Route) {
 
 	for message := range tx {
 		topic := fmt.Sprintf("%s/%s", config.TopicPrefix, message.Topic)
-		client.Publish(topic, QoS1, RETAINED, message.Payload)
+		client.Publish(topic, QoS1, message.Retain, message.Payload)
 	}
 }