[client] Keep the UI running when the notification service fails to start (#6959)

client/ui/notifier.go

@@ -0,0 +1,101 @@
+//go:build !android && !ios && !freebsd && !js
+
+package main
+
+import (
+	"context"
+	"errors"
+	"sync/atomic"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/wailsapp/wails/v3/pkg/application"
+	"github.com/wailsapp/wails/v3/pkg/services/notifications"
+)
+
+var errNotificationsUnavailable = errors.New("notifications unavailable")
+
+// Notifier wraps the Wails notification service so an unavailable backend
+// disables notifications instead of aborting the app. Startup fails for
+// environment reasons (a bare unbundled binary on macOS has no bundle
+// identifier, a headless Linux session has no D-Bus session bus), and Wails
+// treats a service startup error as fatal. After a failed startup every call
+// is a no-op: on macOS, touching UNUserNotificationCenter without a bundle
+// identifier raises an Objective-C exception that recover() cannot catch.
+type Notifier struct {
+	inner     *notifications.NotificationService
+	available atomic.Bool
+}
+
+func newNotifier() *Notifier {
+	return &Notifier{inner: notifications.New()}
+}
+
+// ServiceName implements the Wails service-name hook for startup logs.
+func (n *Notifier) ServiceName() string {
+	return n.inner.ServiceName()
+}
+
+// ServiceStartup starts the platform notifier, downgrading failure to a
+// warning so the app keeps running without notifications.
+func (n *Notifier) ServiceStartup(ctx context.Context, options application.ServiceOptions) error {
+	if err := n.inner.ServiceStartup(ctx, options); err != nil {
+		log.Warnf("notifications disabled: %v", err)
+		return nil
+	}
+	n.available.Store(true)
+	return nil
+}
+
+func (n *Notifier) ServiceShutdown() error {
+	if !n.available.Load() {
+		return nil
+	}
+	return n.inner.ServiceShutdown()
+}
+
+func (n *Notifier) CheckNotificationAuthorization() (bool, error) {
+	if !n.available.Load() {
+		return false, errNotificationsUnavailable
+	}
+	return n.inner.CheckNotificationAuthorization()
+}
+
+func (n *Notifier) RequestNotificationAuthorization() (bool, error) {
+	if !n.available.Load() {
+		return false, errNotificationsUnavailable
+	}
+	return n.inner.RequestNotificationAuthorization()
+}
+
+// SendNotification delivers a notification, silently dropping it when the
+// backend never started (notifications are best-effort everywhere).
+func (n *Notifier) SendNotification(options notifications.NotificationOptions) error {
+	if !n.available.Load() {
+		log.Debugf("notifications disabled, dropping %q", options.ID)
+		return nil
+	}
+	return n.inner.SendNotification(options)
+}
+
+func (n *Notifier) SendNotificationWithActions(options notifications.NotificationOptions) error {
+	if !n.available.Load() {
+		log.Debugf("notifications disabled, dropping %q", options.ID)
+		return nil
+	}
+	return n.inner.SendNotificationWithActions(options)
+}
+
+func (n *Notifier) RegisterNotificationCategory(category notifications.NotificationCategory) error {
+	if !n.available.Load() {
+		return nil
+	}
+	return n.inner.RegisterNotificationCategory(category)
+}
+
+// OnNotificationResponse registers the response callback. Pure Go state, so
+// it is safe (and simply inert) when the backend never started.
+//
+//wails:ignore
+func (n *Notifier) OnNotificationResponse(callback func(result notifications.NotificationResult)) {
+	n.inner.OnNotificationResponse(callback)
+}