Support updating device name at runtime

api-spec.yml

@@ -109,6 +109,22 @@ paths:
                     type: boolean
                   track:
                     $ref: '#/components/schemas/track'
+  /set_device_name:
+    post:
+      description: Set the player device name
+      requestBody:
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [ name ]
+              properties:
+                name:
+                  description: The new device name
+                  type: string
+      responses:
+        200:
+          description: Successful response
   /player/play:
     post:
       description: Starts playing new content

daemon/api_server.go

@@ -74,6 +74,7 @@ const (
 	ApiRequestTypeSetShufflingContext ApiRequestType = "shuffling_context"
 	ApiRequestTypeAddToQueue          ApiRequestType = "add_to_queue"
 	ApiRequestTypeToken               ApiRequestType = "token"
+	ApiRequestSetDeviceName           ApiRequestType = "set_device_name"
 )
 
 type ApiEventType string
@@ -648,6 +649,27 @@ func (s *ConcreteApiServer) serve() {
 
 		s.handleRequest(ApiRequest{Type: ApiRequestTypeToken}, w)
 	})
+	m.HandleFunc("/set_device_name", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+
+		var data struct {
+			Name string `json:"name"`
+		}
+		if err := jsonDecode(r, &data); err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+
+		if len(data.Name) == 0 {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+
+		s.handleRequest(ApiRequest{Type: ApiRequestSetDeviceName, Data: data.Name}, w)
+	})
 	m.HandleFunc("/events", func(w http.ResponseWriter, r *http.Request) {
 		opts := &websocket.AcceptOptions{}
 		if len(s.allowOrigin) > 0 {

daemon/app.go

@@ -30,6 +30,7 @@ type App struct {
 	client *http.Client
 
 	resolver *apresolve.ApResolver
+	zeroconf *zeroconf.Zeroconf
 
 	deviceId    string
 	deviceType  devicespb.DeviceType
@@ -129,6 +130,18 @@ func New(opts *Options) (*App, error) {
 	return app, nil
 }
 
+func (app *App) SetDeviceName(name string) {
+	if app.cfg.DeviceName == name {
+		return
+	}
+
+	app.cfg.DeviceName = name
+
+	if app.zeroconf != nil {
+		app.zeroconf.SetDeviceName(name)
+	}
+}
+
 // Run starts the daemon. It blocks until ctx is cancelled or an unrecoverable
 // error occurs. The credential type configured in cfg.Credentials.Type
 // determines which login flow is used.
@@ -306,7 +319,7 @@ func (app *App) withAppPlayer(ctx context.Context, appPlayerFunc func(context.Co
 		return fmt.Errorf("failed getting endpoints from resolver: %w", err)
 	}
 
-	z, err := zeroconf.NewZeroconf(app.log, app.cfg.ZeroconfPort, app.cfg.DeviceName, app.deviceId, app.deviceType, app.cfg.ZeroconfInterfacesToAdvertise, app.cfg.ZeroconfBackend == "avahi")
+	app.zeroconf, err = zeroconf.NewZeroconf(app.log, app.cfg.ZeroconfPort, app.cfg.DeviceName, app.deviceId, app.deviceType, app.cfg.ZeroconfInterfacesToAdvertise, app.cfg.ZeroconfBackend == "avahi")
 	if err != nil {
 		return fmt.Errorf("failed initializing zeroconf: %w", err)
 	}
@@ -325,7 +338,7 @@ func (app *App) withAppPlayer(ctx context.Context, appPlayerFunc func(context.Co
 		apiCh = make(chan ApiRequest)
 		go currentPlayer.Run(ctx, apiCh, app.mpris.Receive())
 
-		z.SetCurrentUser(currentPlayer.sess.Username())
+		app.zeroconf.SetCurrentUser(currentPlayer.sess.Username())
 	}
 
 	go func() {
@@ -363,16 +376,16 @@ func (app *App) withAppPlayer(ctx context.Context, appPlayerFunc func(context.Co
 				if err != nil {
 					app.log.WithError(err).Errorf("failed restoring session after logout")
 
-					z.SetCurrentUser("")
+					app.zeroconf.SetCurrentUser("")
 				} else if newAppPlayer == nil {
-					z.SetCurrentUser("")
+					app.zeroconf.SetCurrentUser("")
 				} else {
 					apiCh = make(chan ApiRequest)
 					currentPlayer = newAppPlayer
 
 					go newAppPlayer.Run(ctx, apiCh, app.mpris.Receive())
 
-					z.SetCurrentUser(newAppPlayer.sess.Username())
+					app.zeroconf.SetCurrentUser(newAppPlayer.sess.Username())
 
 					app.log.WithField("username", librespot.ObfuscateUsername(currentPlayer.sess.Username())).
 						Debugf("restored session after logout")
@@ -381,7 +394,7 @@ func (app *App) withAppPlayer(ctx context.Context, appPlayerFunc func(context.Co
 		}
 	}()
 
-	return z.Serve(func(req zeroconf.NewUserRequest) bool {
+	return app.zeroconf.Serve(func(req zeroconf.NewUserRequest) bool {
 		if currentPlayer != nil {
 			currentPlayer.Close()
 			currentPlayer = nil

daemon/player.go

@@ -593,11 +593,21 @@ func (p *AppPlayer) handleApiRequest(ctx context.Context, req ApiRequest) (any,
 		return &ApiResponseToken{
 			Token: accessToken,
 		}, nil
+	case ApiRequestSetDeviceName:
+		p.setDeviceName(ctx, req.Data.(string))
+		return nil, nil
 	default:
 		return nil, fmt.Errorf("unknown request type: %s", req.Type)
 	}
 }
 
+func (p *AppPlayer) setDeviceName(ctx context.Context, name string) {
+	p.app.SetDeviceName(name)
+
+	p.state.device.Name = name
+	p.updateState(ctx)
+}
+
 func pointer[T any](d T) *T {
 	return &d
 }

zeroconf/backend.go

@@ -11,6 +11,9 @@ type ServiceRegistrar interface {
 	// txt: TXT record key=value pairs
 	Register(name, serviceType, domain string, port int, txt []string) error
 
+	// UpdateName updates teh service instance name.
+	UpdateName(name string) error
+
 	// Shutdown stops advertising the service and releases resources.
 	Shutdown()
 }

zeroconf/backend_avahi.go

@@ -24,9 +24,14 @@ const (
 // Compatibility: Requires avahi-daemon 0.6.x or later (uses stable D-Bus API).
 // Tested with avahi 0.7 and 0.8.
 type AvahiRegistrar struct {
-	conn       *dbus.Conn
-	entryGroup dbus.BusObject
-	version    string
+	conn    *dbus.Conn
+	version string
+
+	entryGroup  dbus.BusObject
+	serviceType string
+	domain      string
+	port        int
+	txt         []string
 }
 
 // NewAvahiRegistrar creates a new avahi-daemon service registrar.
@@ -80,14 +85,16 @@ func (a *AvahiRegistrar) Register(name, serviceType, domain string, port int, tx
 	server := a.conn.Object(avahiService, avahiServerPath)
 
 	// Create a new entry group for our service
-	var groupPath dbus.ObjectPath
-	err := server.Call(avahiServerIface+".EntryGroupNew", 0).Store(&groupPath)
-	if err != nil {
-		return fmt.Errorf("failed to create entry group: %w", err)
+	if a.entryGroup == nil {
+		var groupPath dbus.ObjectPath
+		err := server.Call(avahiServerIface+".EntryGroupNew", 0).Store(&groupPath)
+		if err != nil {
+			return fmt.Errorf("failed to create entry group: %w", err)
+		}
+
+		a.entryGroup = a.conn.Object(avahiService, groupPath)
 	}
 
-	a.entryGroup = a.conn.Object(avahiService, groupPath)
-
 	// Convert TXT records to [][]byte format required by avahi
 	txtBytes := make([][]byte, len(txt))
 	for i, t := range txt {
@@ -104,7 +111,7 @@ func (a *AvahiRegistrar) Register(name, serviceType, domain string, port int, tx
 	// host (s): hostname, empty for default
 	// port (q): port number (uint16)
 	// txt (aay): TXT record data as array of byte arrays
-	err = a.entryGroup.Call(avahiEntryGroupIface+".AddService", 0,
+	if err := a.entryGroup.Call(avahiEntryGroupIface+".AddService", 0,
 		avahiIfUnspec,    // interface
 		avahiProtoUnspec, // protocol
 		uint32(0),        // flags
@@ -114,20 +121,32 @@ func (a *AvahiRegistrar) Register(name, serviceType, domain string, port int, tx
 		"",               // host (empty = use default hostname)
 		uint16(port),     // port
 		txtBytes,         // TXT records
-	).Err
-	if err != nil {
+	).Err; err != nil {
 		return fmt.Errorf("failed to add service: %w", err)
 	}
 
+	a.serviceType = serviceType
+	a.domain = domain
+	a.port = port
+	a.txt = txt
+
 	// Commit the entry group to publish the service
-	err = a.entryGroup.Call(avahiEntryGroupIface+".Commit", 0).Err
-	if err != nil {
+	if err := a.entryGroup.Call(avahiEntryGroupIface+".Commit", 0).Err; err != nil {
 		return fmt.Errorf("failed to commit entry group: %w", err)
 	}
 
 	return nil
 }
 
+// UpdateName updates the advertised instance service name.
+func (a *AvahiRegistrar) UpdateName(name string) error {
+	if a.entryGroup != nil {
+		_ = a.entryGroup.Call(avahiEntryGroupIface+".Reset", 0).Err
+	}
+
+	return a.Register(name, a.serviceType, a.domain, a.port, a.txt)
+}
+
 // Shutdown removes the service from avahi and releases resources.
 func (a *AvahiRegistrar) Shutdown() {
 	if a.entryGroup != nil {

zeroconf/backend_builtin.go

@@ -11,6 +11,11 @@ import (
 type BuiltinRegistrar struct {
 	server *zeroconf.Server
 	ifaces []net.Interface
+
+	serviceType string
+	domain      string
+	port        int
+	txt         []string
 }
 
 // NewBuiltinRegistrar creates a new built-in mDNS service registrar.
@@ -21,11 +26,22 @@ func NewBuiltinRegistrar(ifaces []net.Interface) *BuiltinRegistrar {
 
 // Register publishes the service using the built-in mDNS responder.
 func (b *BuiltinRegistrar) Register(name, serviceType, domain string, port int, txt []string) error {
+	b.serviceType = serviceType
+	b.domain = domain
+	b.port = port
+	b.txt = txt
+
 	var err error
 	b.server, err = zeroconf.Register(name, serviceType, domain, port, txt, b.ifaces)
 	return err
 }
 
+func (b *BuiltinRegistrar) UpdateName(name string) error {
+	// Zeroconf library does not support dynamic updates, so we need to restart the server with the new name.
+	b.Shutdown()
+	return b.Register(name, b.serviceType, b.domain, b.port, b.txt)
+}
+
 // Shutdown stops the mDNS responder.
 func (b *BuiltinRegistrar) Shutdown() {
 	if b.server != nil {

zeroconf/zeroconf.go

@@ -99,6 +99,14 @@ func NewZeroconf(log librespot.Logger, port int, deviceName, deviceId string, de
 	return z, nil
 }
 
+func (z *Zeroconf) SetDeviceName(name string) {
+	z.deviceName = name
+
+	if err := z.registrar.UpdateName(name); err != nil {
+		z.log.WithError(err).Errorf("failed updating zeroconf service name to %q", name)
+	}
+}
+
 func (z *Zeroconf) SetCurrentUser(username string) {
 	z.userLock.Lock()
 	z.currentUser = username