separate code

src/udi/main.go

@@ -1,150 +1,30 @@
 package main
 
 import "log"
-import "fmt"
 import "os"
 import "os/signal"
-import "strings"
-// import "time"
-import MQTT "github.com/eclipse/paho.mqtt.golang"
-import "github.com/google/uuid"
-import "crypto/tls"
 import um "udi/mqtt"
 
-type Message struct {
-  topic string
-  payload []byte
-}
-
-var messageInputChannel chan Message = make(chan Message, 100)
-var messageOutputChannel chan Message = make(chan Message, 100)
-
-
-func onMessageReceived(client MQTT.Client, message MQTT.Message) {
-  // log.Printf("Message received, topic: %s, payload: %s\n", message.Topic(), message.Payload())
-  m := Message { 
-    topic: message.Topic(), 
-    payload: message.Payload(),
-  }
-  select {
-  case messageInputChannel <- m:
-    {}
-    //log.Println("Message sent to channel")
-  default:
-    log.Println("Channel full, message lost")
-  }
-}
-
-func onConnectionLost(client MQTT.Client, error error) {
-  log.Printf("Connection lost, error %s", error)
-}
-
-func onReconnecting(client MQTT.Client, clientOpts *MQTT.ClientOptions) {
-  log.Println("Oops, connection lost, already reconnecting ...")
-}
-
-
-func onConnect(client MQTT.Client) {
-  topicsStr := os.Getenv("MQTT_SUBSCRIBE_TOPICS")
-  if topicsStr == "" {
-    log.Fatal("No topics given, set env var MQTT_SUBSCRIBE_TOPICS")
-  }
-  topics := strings.Split(topicsStr, ",")
-  for _, topic := range topics {
-    if token := client.Subscribe(topic, 0, onMessageReceived); token.Wait() && token.Error() != nil {
-      log.Fatalf("Unable to subscribe to topic %s, error %s", topic, token.Error())
-    }
-    log.Printf("Successfully subscribed to topic %s", topic)
-  }
-}
 
 func inputDispatcher() {
   for {
     select {
-    case message := <- messageInputChannel:
-      log.Printf("Message arrived in inputDispatcher, topic: %s, payload: %s\n", message.topic, message.payload)
+    case message := <- um.InputChannel:
+      log.Printf("Message arrived in inputDispatcher, topic: %s, payload: %s\n", message.Topic, message.Payload)
     }
   }
 }
 
-func outputDispatcher(client MQTT.Client) {
-  for {
-    select {
-    case message := <- messageOutputChannel:
-      log.Printf("Message arrived in outputDispatcher, topic: %s, payload: %s\n", message.topic, message.payload)
-      if token := client.Publish(message.topic, 0, false, message.payload); token.Wait() && token.Error() != nil {
-        log.Printf("Unable to publish, error %s", token.Error())
-      }
-      log.Println("Successfully published")
-    }
-  }
-}
-
-func startMqttClient() MQTT.Client {
-  broker := os.Getenv("MQTT_BROKER")
-  if broker == "" {
-    log.Fatal("No broker given, set env var MQTT_BROKER")
-  }
-
-  prefix := "UDI"
-  uuid := uuid.New()
-  clientId := fmt.Sprintf("%s-%s", prefix, uuid)
-
-  opts := MQTT.NewClientOptions().
-    AddBroker(broker).
-    SetClientID(clientId).
-    SetConnectionLostHandler(onConnectionLost).
-    SetOnConnectHandler(onConnect).
-    SetReconnectingHandler(onReconnecting).
-    SetConnectRetry(true)
-
-  username := os.Getenv("MQTT_USERNAME")
-  if username != "" {
-    opts.SetUsername(username)
-  }
-
-  password := os.Getenv("MQTT_PASSWORD")
-  if password != "" {
-    opts.SetPassword(password)
-  }
-
-  enableTls := os.Getenv("MQTT_ENABLE_TLS")
-  if enableTls == "true" {
-    log.Println("Enableing TLS connection")
-    tlsConfig := &tls.Config { 
-      InsecureSkipVerify: true, 
-    }
-    opts.SetTLSConfig(tlsConfig)
-	}
-
-  log.Println("Trying to connect to broker")
-  client := MQTT.NewClient(opts)
-  if token := client.Connect(); token.Wait() && token.Error() != nil {
-    log.Fatalf("Unable to connect to broker %s, error %s", broker, token.Error())
-  }
-  log.Printf("Successfully connected to broker %s", broker)
-
-  return client
-}
-
-func stopMqttClient(client MQTT.Client) {
-  log.Println("Disconnecting from broker")
-  client.Disconnect(250)
-}
-
 func main() {
   log.SetPrefix("UDI: ")
   log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)
 
   log.Println("UDI starting")
-  um.TestMqtt()
 
   go inputDispatcher()
 
-  mqttClient := startMqttClient()
-  defer stopMqttClient(mqttClient)
-
-  go outputDispatcher(mqttClient)
+  um.StartMqttClient()
+  defer um.StopMqttClient()
 
   log.Println("UDI running")
 

src/udi/mqtt/mqtt.go

@@ -1,9 +1,126 @@
 package mqtt
 
 import "log"
+import "fmt"
+import "os"
+import "strings"
+// import "time"
+import MQTT "github.com/eclipse/paho.mqtt.golang"
+import "github.com/google/uuid"
+import "crypto/tls"
 
-
-func TestMqtt() {
-  log.Println("test mqtt")
+type Message struct {
+  Topic string
+  Payload []byte
+}
+
+var InputChannel chan Message = make(chan Message, 100)
+var OutputChannel chan Message = make(chan Message, 100)
+
+var mqttClient MQTT.Client
+
+func onMessageReceived(client MQTT.Client, message MQTT.Message) {
+  // log.Printf("Message received, topic: %s, payload: %s\n", message.Topic(), message.Payload())
+  m := Message { 
+    Topic: message.Topic(), 
+    Payload: message.Payload(),
+  }
+  select {
+  case InputChannel <- m:
+    {}
+    //log.Println("Message sent to channel")
+  default:
+    log.Println("Channel full, message lost")
+  }
+}
+
+func onConnectionLost(client MQTT.Client, error error) {
+  log.Printf("Connection lost, error %s", error)
+}
+
+func onReconnecting(client MQTT.Client, clientOpts *MQTT.ClientOptions) {
+  log.Println("Oops, connection lost, already reconnecting ...")
+}
+
+
+func onConnect(client MQTT.Client) {
+  topicsStr := os.Getenv("MQTT_SUBSCRIBE_TOPICS")
+  if topicsStr == "" {
+    log.Fatal("No topics given, set env var MQTT_SUBSCRIBE_TOPICS")
+  }
+  topics := strings.Split(topicsStr, ",")
+  for _, topic := range topics {
+    if token := client.Subscribe(topic, 0, onMessageReceived); token.Wait() && token.Error() != nil {
+      log.Fatalf("Unable to subscribe to topic %s, error %s", topic, token.Error())
+    }
+    log.Printf("Successfully subscribed to topic %s", topic)
+  }
+}
+
+func outputDispatcher(client MQTT.Client) {
+  for {
+    select {
+    case message := <- OutputChannel:
+      log.Printf("Message arrived in outputDispatcher, topic: %s, payload: %s\n", message.Topic, message.Payload)
+      if token := client.Publish(message.Topic, 0, false, message.Payload); token.Wait() && token.Error() != nil {
+        log.Printf("Unable to publish, error %s", token.Error())
+      }
+      log.Println("Successfully published")
+    }
+  }
+}
+
+func StartMqttClient() {
+  broker := os.Getenv("MQTT_BROKER")
+  if broker == "" {
+    log.Fatal("No broker given, set env var MQTT_BROKER")
+  }
+
+  prefix := "UDI"
+  uuid := uuid.New()
+  clientId := fmt.Sprintf("%s-%s", prefix, uuid)
+
+  opts := MQTT.NewClientOptions().
+    AddBroker(broker).
+    SetClientID(clientId).
+    SetConnectionLostHandler(onConnectionLost).
+    SetOnConnectHandler(onConnect).
+    SetReconnectingHandler(onReconnecting).
+    SetConnectRetry(true)
+
+  username := os.Getenv("MQTT_USERNAME")
+  if username != "" {
+    opts.SetUsername(username)
+  }
+
+  password := os.Getenv("MQTT_PASSWORD")
+  if password != "" {
+    opts.SetPassword(password)
+  }
+
+  enableTls := os.Getenv("MQTT_ENABLE_TLS")
+  if enableTls == "true" {
+    log.Println("Enableing TLS connection")
+    tlsConfig := &tls.Config { 
+      InsecureSkipVerify: true, 
+    }
+    opts.SetTLSConfig(tlsConfig)
+	}
+
+  log.Println("Trying to connect to broker")
+  mqttClient = MQTT.NewClient(opts)
+  if token := mqttClient.Connect(); token.Wait() && token.Error() != nil {
+    log.Fatalf("Unable to connect to broker %s, error %s", broker, token.Error())
+  }
+  log.Printf("Successfully connected to broker %s", broker)
+
+  go outputDispatcher(mqttClient)
+
+  return
+}
+
+func StopMqttClient() {
+  log.Println("Disconnecting from broker")
+  mqttClient.Disconnect(250)
 }