feat(agent): 🎨 MQTT agent adjustments

add Power Off and Reboot controls; alter device info presented to Home Assistant to match registration info; simplify code and renaming; update documentation

docs/mqtt.md

@@ -53,4 +53,10 @@ service call.
 
 There is a significant discrepancy in permissions between the device running Go Hass Agent and Home Assistant.
 
-Go Hass Agent runs under a user account on a device. So the above controls will only work where that user has permissions to run the underlying actions on that device. Home Assistant does not currently offer any fine-grained access control for controls like the above. So any Home Assistant user will be able to run any of the controls. This means that a Home Assistant user not associated with the device user running the agent can use the exposed controls to issue potentially disruptive actions on a device that another user is accessing.
+Go Hass Agent runs under a user account on a device. So the above controls will only work where that user has permissions to run the underlying actions on that device. Home Assistant does not currently offer any fine-grained access control for controls like the above. So any Home Assistant user will be able to run any of the controls. This means that a Home Assistant user not associated with the device user running the agent can use the exposed controls to issue potentially disruptive actions on a device that another user is accessing.
+
+## Implementation Details
+
+### Linux
+
+Controls rely on distribution/system support for `systemd-logind` and a working D-Bus connection.

internal/agent/agent.go

@@ -97,7 +97,7 @@ func (agent *Agent) Run(c string, cfg config.Config, trk SensorTracker) {
 				wg.Add(1)
 				go func() {
 					defer wg.Done()
-					agent.runMQTTWorker(runnerCtx)
+					runMQTTWorker(runnerCtx)
 				}()
 			}
 			// Listen for notifications from Home Assistant.
@@ -118,7 +118,6 @@ func (agent *Agent) Run(c string, cfg config.Config, trk SensorTracker) {
 		agent.ui.Run(agent.done)
 	}
 	wg.Wait()
-	log.Debug().Msg("here")
 }
 
 func (agent *Agent) Register(cfg config.Config, trk SensorTracker) {

internal/agent/mqtt.go

@@ -13,31 +13,29 @@ import (
 	"github.com/joshuar/go-hass-agent/internal/agent/config"
 )
 
-type mqttDevice struct {
-	configs map[string]*mqtthass.EntityConfig
+type mqttObj struct {
+	entities map[string]*mqtthass.EntityConfig
 }
 
-func (d *mqttDevice) Name() string {
+func (o *mqttObj) Name() string {
 	return config.AppName
 }
 
-func (d *mqttDevice) Configuration() []*mqttapi.Msg {
+func (o *mqttObj) Configuration() []*mqttapi.Msg {
 	var msgs []*mqttapi.Msg
-
-	for id, c := range d.configs {
+	for id, c := range o.entities {
 		if msg, err := mqtthass.MarshalConfig(c); err != nil {
 			log.Error().Err(err).Msgf("Failed to marshal payload for %s.", id)
 		} else {
 			msgs = append(msgs, msg)
 		}
 	}
-
 	return msgs
 }
 
-func (d *mqttDevice) Subscriptions() []*mqttapi.Subscription {
+func (o *mqttObj) Subscriptions() []*mqttapi.Subscription {
 	var subs []*mqttapi.Subscription
-	for _, v := range d.configs {
+	for _, v := range o.entities {
 		if v.CommandCallback != nil {
 			if sub, err := mqtthass.MarshalSubscription(v); err != nil {
 				log.Error().Err(err).Str("entity", v.Entity.Name).
@@ -50,6 +48,6 @@ func (d *mqttDevice) Subscriptions() []*mqttapi.Subscription {
 	return subs
 }
 
-func (d *mqttDevice) States() []*mqttapi.Msg {
+func (o *mqttObj) States() []*mqttapi.Msg {
 	return nil
 }

internal/agent/mqtt_linux.go

@@ -9,59 +9,88 @@ import (
 	"context"
 
 	MQTT "github.com/eclipse/paho.mqtt.golang"
+	"github.com/godbus/dbus/v5"
 	"github.com/rs/zerolog/log"
 
 	mqtthass "github.com/joshuar/go-hass-anything/v3/pkg/hass"
 
 	"github.com/joshuar/go-hass-agent/internal/agent/config"
+	"github.com/joshuar/go-hass-agent/internal/linux"
 	"github.com/joshuar/go-hass-agent/pkg/linux/dbusx"
 )
 
-func (a *Agent) newMQTTDevice(ctx context.Context) *mqttDevice {
-	cfg := config.FetchFromContext(ctx)
+const (
+	dbusDest           = "org.freedesktop.login1"
+	dbusLockMethod     = dbusDest + ".Session.Lock"
+	dbusUnlockMethod   = dbusDest + ".Session.UnLock"
+	dbusRebootMethod   = dbusDest + ".Manager.Reboot"
+	dbusPowerOffMethod = dbusDest + ".Manager.PowerOff"
+)
+
+func newMQTTObject(ctx context.Context) *mqttObj {
+	appName := "go_hass_agent"
+
+	baseEntity := func(entityID string) *mqtthass.EntityConfig {
+		return mqtthass.NewEntityByID(entityID, appName).
+			AsButton().
+			WithDefaultOriginInfo().
+			WithDeviceInfo(mqttDevice())
+	}
 
-	var deviceName string
-	cfg.Get(config.PrefDeviceName, &deviceName)
-	deviceInfo := &mqtthass.Device{
-		Name:         deviceName,
-		URL:          "https://github.com/joshuar/go-hass-agent",
-		SWVersion:    config.AppVersion,
-		Manufacturer: "go-hass-agent",
-		Model:        a.AppID(),
-		Identifiers:  []string{"go-hass-agent01"},
+	dbusCall := func(ctx context.Context, path dbus.ObjectPath, dest, method string, args ...any) error {
+		return dbusx.NewBusRequest(ctx, dbusx.SystemBus).
+			Path(path).
+			Destination(dest).
+			Call(method, args...)
 	}
 
 	sessionPath := dbusx.GetSessionPath(ctx)
-	configs := make(map[string]*mqtthass.EntityConfig)
-	configs["lock_session"] = mqtthass.NewEntityByID("lock_session", "go_hass_agent").
-		AsButton().
-		WithDefaultOriginInfo().
-		WithDeviceInfo(deviceInfo).
+	entities := make(map[string]*mqtthass.EntityConfig)
+	entities["lock_session"] = baseEntity("lock_session").
 		WithIcon("mdi:eye-lock").
 		WithCommandCallback(func(_ MQTT.Client, _ MQTT.Message) {
-			err := dbusx.NewBusRequest(ctx, dbusx.SystemBus).
-				Path(sessionPath).
-				Destination("org.freedesktop.login1").
-				Call("org.freedesktop.login1.Session.Lock")
+			err := dbusCall(ctx, sessionPath, dbusDest, dbusLockMethod)
 			if err != nil {
 				log.Warn().Err(err).Msg("Could not lock session.")
 			}
 		})
-	configs["unlock_session"] = mqtthass.NewEntityByID("unlock_session", "go_hass_agent").
-		AsButton().
-		WithDefaultOriginInfo().
-		WithDeviceInfo(deviceInfo).
+	entities["unlock_session"] = baseEntity("unlock_session").
 		WithIcon("mdi:eye-lock-open").
 		WithCommandCallback(func(_ MQTT.Client, _ MQTT.Message) {
-			err := dbusx.NewBusRequest(ctx, dbusx.SystemBus).
-				Path(sessionPath).
-				Destination("org.freedesktop.login1").
-				Call("org.freedesktop.login1.Session.UnLock")
+			err := dbusCall(ctx, sessionPath, dbusDest, dbusUnlockMethod)
 			if err != nil {
 				log.Warn().Err(err).Msg("Could not unlock session.")
 			}
 		})
-	return &mqttDevice{
-		configs: configs,
+	entities["reboot"] = baseEntity("reboot").
+		WithIcon("mdi:restart").
+		WithCommandCallback(func(_ MQTT.Client, _ MQTT.Message) {
+			err := dbusCall(ctx, dbus.ObjectPath("/org/freedesktop/login1"), dbusDest, dbusRebootMethod, true)
+			if err != nil {
+				log.Warn().Err(err).Msg("Could not reboot session.")
+			}
+		})
+	entities["poweroff"] = baseEntity("poweroff").
+		WithIcon("mdi:power").
+		WithCommandCallback(func(_ MQTT.Client, _ MQTT.Message) {
+			err := dbusCall(ctx, dbus.ObjectPath("/org/freedesktop/login1"), dbusDest, dbusPowerOffMethod, true)
+			if err != nil {
+				log.Warn().Err(err).Msg("Could not power off session.")
+			}
+		})
+	return &mqttObj{
+		entities: entities,
+	}
+}
+
+func mqttDevice() *mqtthass.Device {
+	dev := linux.NewDevice(config.AppName, config.AppVersion)
+	return &mqtthass.Device{
+		Name:         dev.DeviceName(),
+		URL:          config.AppURL,
+		SWVersion:    dev.OsVersion(),
+		Manufacturer: dev.Manufacturer(),
+		Model:        dev.Model(),
+		Identifiers:  []string{dev.DeviceID()},
 	}
 }

internal/agent/runners.go

@@ -148,28 +148,28 @@ func (agent *Agent) runNotificationsWorker(ctx context.Context) {
 
 // runMQTTWorker will set up a connection to MQTT and listen on topics for
 // controlling this device from Home Assistant.
-func (agent *Agent) runMQTTWorker(ctx context.Context) {
+func runMQTTWorker(ctx context.Context) {
 	cfg := config.FetchFromContext(ctx)
 
 	c, err := mqttapi.NewMQTTClient(cfg.Path())
 	if err != nil {
 		log.Error().Err(err).Msg("Could not start MQTT client.")
 		return
 	}
-	d := agent.newMQTTDevice(ctx)
-	if err := mqtthass.Register(d, c); err != nil {
+	o := newMQTTObject(ctx)
+	if err := mqtthass.Register(o, c); err != nil {
 		log.Error().Err(err).Msg("Failed to register app!")
 		return
 	}
-	if err := mqtthass.Subscribe(d, c); err != nil {
+	if err := mqtthass.Subscribe(o, c); err != nil {
 		log.Error().Err(err).Msg("Could not activate subscriptions.")
 	}
 	log.Debug().Msg("Listening for events on MQTT.")
 
 	<-ctx.Done()
 }
 
-func (agent *Agent) resetMQTTWorker(ctx context.Context) {
+func resetMQTTWorker(ctx context.Context) {
 	cfg := config.FetchFromContext(ctx)
 
 	c, err := mqttapi.NewMQTTClient(cfg.Path())
@@ -179,7 +179,7 @@ func (agent *Agent) resetMQTTWorker(ctx context.Context) {
 	}
 
 	log.Info().Msgf("Clearing agent data from Home Assistant.")
-	d := agent.newMQTTDevice(ctx)
+	d := newMQTTObject(ctx)
 
 	if err := mqtthass.UnRegister(d, c); err != nil {
 		log.Error().Err(err).Msg("Failed to unregister app!")