add new ip ping for udp device

add new function start and stop bus

models/bus.go

@@ -1,12 +1,13 @@
 package models
 
 import (
+	"context"
 	"fmt"
-	"log"
 	"net"
 	"time"
 
 	"github.com/tatsushid/go-fastping"
+	"github.com/tecamino/tecamino-logger/logging"
 )
 
 // Art-Net constants
@@ -16,10 +17,12 @@ const (
 
 // Art-Net Interface
 type Bus struct {
-	Name string `yaml:"name" json:"name"`
-	Ip   string `yaml:"ip" json:"ip"`
-	Port *int   `yaml:"port" json:"port,omitempty"`
-	Data *DMX   `yaml:"-" json:"-"`
+	Name      string             `yaml:"name" json:"name"`
+	Ip        string             `yaml:"ip" json:"ip"`
+	Port      *int               `yaml:"port" json:"port,omitempty"`
+	Data      *DMX               `yaml:"-" json:"-"`
+	Watchdog  context.CancelFunc `yaml:"-" json:"-"`
+	Reachable bool               `yaml:"-" json:"-"`
 }
 
 // adds new Art-Net interface to driver port 0 = 6454 (default art-net)
@@ -92,8 +95,51 @@ func (b *Bus) Poll(interval time.Duration) error {
 	}
 }
 
-// start polling dmx data in milliseconds 0 = aprox. 44Hertz
+// start bus
+func (b *Bus) Start(log *logging.Logger) {
+	var ctx context.Context
+	ctx, b.Watchdog = context.WithCancel(context.Background())
+
+	go func() {
+		var interval time.Duration = 10 * time.Second
+		log.Info("bus.Start", fmt.Sprintf("device:%s ip:%s watchdog stopped", b.Name, b.Ip))
+		for {
+			select {
+			case <-ctx.Done():
+				log.Info("bus.Start", fmt.Sprintf("device:%s ip:%s watchdog stopped", b.Name, b.Ip))
+				b.Reachable = false
+				return
+			default:
+				b.Reachable = false
+				if reached, err := isUDPReachable(b.Ip); err != nil {
+					log.Error("bus.Start", err)
+					interval = 5 * time.Second
+				} else if !reached {
+					log.Error("bus.Start", fmt.Sprintf("device:%s ip:%s not reached", b.Name, b.Ip))
+					interval = 5 * time.Second
+				} else {
+					b.Reachable = true
+					log.Info("bus.Start", fmt.Sprintf("device:%s ip:%s watchdog running", b.Name, b.Ip))
+					interval = 30 * time.Second
+				}
+				time.Sleep(interval)
+			}
+		}
+	}()
+}
+
+// stop bus
+func (b *Bus) Stop() {
+	if b.Watchdog != nil {
+		b.Watchdog()
+	}
+}
+
+// send dmx data
 func (b *Bus) SendData() error {
+	if !b.Reachable {
+		return nil
+	}
 	// Send packet over UDP
 	conn, err := net.DialUDP("udp", nil, &net.UDPAddr{
 		IP:   net.ParseIP(b.Ip),
@@ -105,16 +151,6 @@ func (b *Bus) SendData() error {
 	}
 	defer conn.Close()
 
-	go func() {
-		if reached, err := isUDPReachable(b.Ip); err != nil {
-			log.Println(err)
-			return
-		} else if !reached {
-			log.Println("device not reachable")
-			return
-		}
-	}()
-
 	_, err = conn.Write(NewArtNetPackage(b.Data))
 
 	return err