kiosk presence helper added

.gitignore

@@ -23,3 +23,5 @@ go.work
 /cmd/git_version.go
 /dist
 .env
+screen_off
+screen_on

kiosk/kiosk.go

@@ -3,6 +3,7 @@ package kiosk
 import (
 	"context"
 	"log/slog"
+	"os/exec"
 
 	"github.com/spf13/viper"
 )
@@ -15,6 +16,7 @@ type configObj struct {
 	username       string
 	password       string
 	presenceTopic  string
+	shell          string
 	screen_on_cmd  string
 	screen_off_cmd string
 }
@@ -27,9 +29,31 @@ func Run(rootLogger *slog.Logger, exitch chan bool, ctx context.Context) {
 	config.username = viper.GetString("mqtt_broker_user")
 	config.password = viper.GetString("mqtt_broker_password")
 	config.presenceTopic = viper.GetString("mqtt_presence_topic")
+	config.shell = viper.GetString("kiosk_cmd_shell")
 	config.screen_on_cmd = viper.GetString("kiosk_cmd_screen_on")
 	config.screen_off_cmd = viper.GetString("kiosk_cmd_screen_off")
 	config.logger.Info("starting MQTT broker client")
 	brokerConsume(ctx)
 	exitch <- true
 }
+
+func handlePresenceMessage(msg [2]string) {
+	logger := config.logger
+	logger.Debug("received presence message", "msg", msg)
+	cmdStr := ""
+	switch msg[1] {
+	case "on":
+		cmdStr = config.screen_on_cmd
+	case "off":
+		cmdStr = config.screen_off_cmd
+	default:
+		logger.Warn("recieved unexpected presence message", "msg", msg)
+		return
+	}
+	logger.Info("Presence change event", "presence", msg[1], "command", cmdStr)
+	cmd := exec.Command(config.shell, "-c", cmdStr)
+	err := cmd.Run()
+	if err != nil {
+		logger.Error("error while executing command", "msg", msg, "command", cmdStr, "err", err)
+	}
+}

kiosk/mqtt.go

@@ -45,7 +45,7 @@ func brokerConsume(ctx context.Context) {
 				done <- true
 				return
 			case msg := <-messages:
-				logger.Info("MQTT message received", "topic", msg[0], "body", msg[1])
+				go handlePresenceMessage(msg)
 			}
 		}
 	}()