feat: app child key derived from wallet master key

nip47/nip47_service.go

@@ -28,6 +28,7 @@ type Nip47Service interface {
 	events.EventSubscriber
 	StartNotifier(ctx context.Context, relay *nostr.Relay, lnClient lnclient.LNClient)
 	HandleEvent(ctx context.Context, relay nostrmodels.Relay, event *nostr.Event, lnClient lnclient.LNClient)
+	GetNip47Info(ctx context.Context, relay *nostr.Relay, appWalletPubKey string) (*nostr.Event, error)
 	PublishNip47Info(ctx context.Context, relay nostrmodels.Relay, appWalletPubKey string, appWalletPrivKey string, lnClient lnclient.LNClient) (*nostr.Event, error)
 	PublishNip47InfoDeletion(ctx context.Context, relay nostrmodels.Relay, appWalletPubKey string, appWalletPrivKey string, infoEventId string) error
 	CreateResponse(initialEvent *nostr.Event, content interface{}, tags nostr.Tags, ss []byte, walletPrivKey string) (result *nostr.Event, err error)

nip47/notifications/nip47_notifier.go

@@ -151,7 +151,14 @@ func (notifier *Nip47Notifier) notifySubscriber(ctx context.Context, app *db.App
 	allTags := nostr.Tags{[]string{"p", app.AppPubkey}}
 	allTags = append(allTags, tags...)
 
-	appWalletPubKey, _ := nostr.GetPublicKey(appWalletPrivKey)
+	appWalletPubKey, err := nostr.GetPublicKey(appWalletPrivKey)
+	if err != nil {
+		logger.Logger.WithFields(logrus.Fields{
+			"notification": notification,
+			"appId":        app.ID,
+		}).WithError(err).Error("Failed to calculate app wallet pub key")
+		return
+	}
 
 	event := &nostr.Event{
 		PubKey:    appWalletPubKey,

nip47/publish_nip47_info.go

@@ -12,6 +12,25 @@ import (
 	"github.com/nbd-wtf/go-nostr"
 )
 
+func (svc *nip47Service) GetNip47Info(ctx context.Context, relay *nostr.Relay, appWalletPubKey string) (*nostr.Event, error) {
+	filter := nostr.Filter{
+		Kinds:   []int{models.INFO_EVENT_KIND},
+		Authors: []string{appWalletPubKey},
+		Limit:   1,
+	}
+
+	events, err := relay.QuerySync(ctx, filter)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(events) == 0 {
+		return nil, nil
+	}
+
+	return events[0], nil
+}
+
 func (svc *nip47Service) PublishNip47Info(ctx context.Context, relay nostrmodels.Relay, appWalletPubKey string, appWalletPrivKey string, lnClient lnclient.LNClient) (*nostr.Event, error) {
 	// TODO: should the capabilities be based on the app permissions? (for non-legacy apps)
 	capabilities := lnClient.GetSupportedNIP47Methods()

service/create_app_consumer.go

@@ -34,14 +34,20 @@ func (s *createAppConsumer) ConsumeEvent(ctx context.Context, event *events.Even
 	walletPrivKey, err := s.svc.keys.GetAppWalletKey(id)
 	if err != nil {
 		logger.Logger.WithError(err).Error("Failed to calculate app wallet priv key")
+		return
 	}
 	walletPubKey, err := nostr.GetPublicKey(walletPrivKey)
 	if err != nil {
 		logger.Logger.WithError(err).Error("Failed to calculate app wallet pub key")
+		return
 	}
 
 	go func() {
-		err = s.svc.startAppWalletSubscription(ctx, s.relay, walletPubKey, walletPrivKey)
+		nip47EventInfo, err := s.svc.GetNip47Service().PublishNip47Info(ctx, s.relay, walletPubKey, walletPrivKey, s.svc.lnClient)
+		if err != nil {
+			logger.Logger.WithError(err).Error("Could not publish NIP47 info")
+		}
+		err = s.svc.startAppWalletSubscription(ctx, s.relay, walletPubKey, nip47EventInfo)
 		if err != nil {
 			logger.Logger.WithError(err).WithFields(logrus.Fields{
 				"app_id": id}).Error("Failed to subscribe to wallet")

service/delete_app_consumer.go

@@ -14,7 +14,7 @@ type deleteAppConsumer struct {
 	relay             *nostr.Relay
 	nostrSubscription *nostr.Subscription
 	svc               *service
-	infoEventId       string
+	nip47InfoEvent    *nostr.Event
 }
 
 // When an app is deleted, unsubscribe from events for that app on the relay
@@ -28,20 +28,31 @@ func (s *deleteAppConsumer) ConsumeEvent(ctx context.Context, event *events.Even
 		logger.Logger.WithField("event", event).Error("Failed to cast event.Properties to map")
 		return
 	}
-	id, _ := properties["id"].(uint)
+	id, ok := properties["id"].(uint)
+	if !ok {
+		logger.Logger.WithField("event", event).Error("missing id in properties event")
+		return
+	}
 
 	walletPrivKey, err := s.svc.keys.GetAppWalletKey(id)
 	if err != nil {
 		logger.Logger.WithError(err).WithField("id", id).Error("Failed to calculate app wallet priv key")
+		return
+	}
+	walletPubKey, err := nostr.GetPublicKey(walletPrivKey)
+	if err != nil {
+		logger.Logger.WithError(err).WithField("id", id).Error("Failed to calculate app wallet pub key")
+		return
 	}
-	walletPubKey, _ := nostr.GetPublicKey(walletPrivKey)
 	// Note: for legacy apps this check will always return false as the wallet pubkey
 	// generated by the id will not match the master key which is used for all legacy apps
 	if s.walletPubkey == walletPubKey {
 		s.nostrSubscription.Unsub()
-		err := s.svc.nip47Service.PublishNip47InfoDeletion(ctx, s.relay, walletPubKey, walletPrivKey, s.infoEventId)
-		if err != nil {
-			logger.Logger.WithError(err).WithField("event", event).Error("Failed to publish nip47 info deletion")
+		if s.nip47InfoEvent != nil {
+			err := s.svc.nip47Service.PublishNip47InfoDeletion(ctx, s.relay, walletPubKey, walletPrivKey, s.nip47InfoEvent.ID)
+			if err != nil {
+				logger.Logger.WithError(err).WithField("event", event).Error("Failed to publish nip47 info deletion")
+			}
 		}
 	}
 }

service/start.go

@@ -99,13 +99,32 @@ func (svc *service) startNostr(ctx context.Context, encryptionKey string) error
 			// register a subscriber for events of "app_created" which handles creation of nostr subscription for new app
 			svc.eventPublisher.RegisterSubscriber(&createAppConsumer{svc: svc, relay: relay})
 
-			// legacy single wallet subscription - only subscribe once for all legacy apps
-			// to ensure we do not get duplicate events
-			err = svc.startAppWalletSubscription(ctx, relay, svc.keys.GetNostrPublicKey(), svc.keys.GetNostrSecretKey())
-			if err != nil {
-				//err being non-nil means that we have an error on the websocket error channel. In this case we just try to reconnect.
-				logger.Logger.WithError(err).Error("Got an error from the relay while listening to subscription.")
-				continue
+			// check if there are still legacy apps in DB
+			var legacyAppCount int64
+			result := svc.db.Model(&db.App{}).Where("wallet_pubkey IS NULL").Count(&legacyAppCount)
+			if result.Error != nil {
+				logger.Logger.WithError(result.Error).Error("Failed to count Legacy Apps")
+				return
+			}
+			if legacyAppCount > 0 {
+				// re-publish single NIP47 event info for legacy apps
+				_, err := svc.GetNip47Service().PublishNip47Info(ctx, relay, svc.keys.GetNostrPublicKey(), svc.keys.GetNostrSecretKey(), svc.lnClient)
+				if err != nil {
+					logger.Logger.WithError(err).Error("Could not publish NIP47 info for legacy apps")
+					continue
+				}
+
+				// legacy single wallet subscription - only subscribe once for all legacy apps
+				// to ensure we do not get duplicate events
+				err = svc.startAppWalletSubscription(ctx, relay, svc.keys.GetNostrPublicKey(), nil)
+				if err != nil {
+					//err being non-nil means that we have an error on the websocket error channel. In this case we just try to reconnect.
+					logger.Logger.WithError(err).Error("Got an error from the relay while listening to subscription.")
+					continue
+				}
+			} else {
+				// there is only new apps, so no single master key nostr subscription needed
+				<-ctx.Done()
 			}
 			//err being nil means that the context was canceled and we should exit the program.
 			break
@@ -126,25 +145,41 @@ func (svc *service) startAllExistingAppsWalletSubscriptions(ctx context.Context,
 
 	for _, app := range apps {
 		go func(app db.App) {
-			err := svc.startAppWalletSubscription(ctx, relay, *app.WalletPubkey, "")
+
+			// get nip47 event info for this app wallet key
+			nip47InfoEvent, err := svc.GetNip47Service().GetNip47Info(ctx, relay, *app.WalletPubkey)
+			if err != nil {
+				logger.Logger.WithError(err).Error("Could not get nip47 info event")
+				return
+			}
+			if nip47InfoEvent == nil {
+				// nip47 info event missing for this app, re-publish it
+				walletPrivKey, err := svc.keys.GetAppWalletKey(app.ID)
+				if err != nil {
+					logger.Logger.WithError(err).WithFields(logrus.Fields{
+						"app_id": app.ID}).Error("Failed to calculate app wallet priv key")
+					return
+				}
+
+				nip47InfoEvent, err = svc.GetNip47Service().PublishNip47Info(ctx, relay, *app.WalletPubkey, walletPrivKey, svc.lnClient)
+				if err != nil {
+					logger.Logger.WithError(err).WithFields(logrus.Fields{
+						"app_id": app.ID}).Error("Could not re-publish NIP47 info for app")
+					return
+				}
+			}
+
+			err = svc.startAppWalletSubscription(ctx, relay, *app.WalletPubkey, nip47InfoEvent)
 			if err != nil {
 				logger.Logger.WithError(err).WithFields(logrus.Fields{
 					"app_id": app.ID}).Error("Failed to subscribe to wallet")
+				return
 			}
 		}(app)
 	}
 }
 
-func (svc *service) startAppWalletSubscription(ctx context.Context, relay *nostr.Relay, appWalletPubKey string, appWalletPrivKey string) error {
-	var infoEventId string
-	if appWalletPrivKey != "" {
-		infoEvent, err := svc.GetNip47Service().PublishNip47Info(ctx, relay, appWalletPubKey, appWalletPrivKey, svc.lnClient)
-		if err != nil {
-			logger.Logger.WithError(err).Error("Could not publish NIP47 info")
-			return err
-		}
-		infoEventId = infoEvent.ID
-	}
+func (svc *service) startAppWalletSubscription(ctx context.Context, relay *nostr.Relay, appWalletPubKey string, nip47InfoEvent *nostr.Event) error {
 
 	logger.Logger.Info("Subscribing to events for wallet ", appWalletPubKey)
 	sub, err := relay.Subscribe(ctx, svc.createFilters(appWalletPubKey))
@@ -154,7 +189,7 @@ func (svc *service) startAppWalletSubscription(ctx context.Context, relay *nostr
 	}
 
 	// register a subscriber for "app_deleted" events, which handles nostr subscription cancel and nip47 info event deletion
-	svc.eventPublisher.RegisterSubscriber(&deleteAppConsumer{nostrSubscription: sub, walletPubkey: appWalletPubKey, svc: svc, relay: relay, infoEventId: infoEventId})
+	svc.eventPublisher.RegisterSubscriber(&deleteAppConsumer{nostrSubscription: sub, walletPubkey: appWalletPubKey, svc: svc, relay: relay, nip47InfoEvent: nip47InfoEvent})
 
 	err = svc.StartSubscription(sub.Context, sub)
 	if err != nil {