feat: handle nostr subscriptions for lifecycle of apps

alby/alby_oauth_service.go

@@ -535,6 +535,7 @@ func (svc *albyOAuthService) LinkAccount(ctx context.Context, lnClient lnclient.
 		scopes,
 		false,
 		nil,
+		svc.keys.GetBIP32ChildKey,
 	)
 
 	if err != nil {

api/api.go

@@ -2,7 +2,6 @@ package api
 
 import (
 	"context"
-	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -30,7 +29,6 @@ import (
 	"github.com/getAlby/hub/service/keys"
 	"github.com/getAlby/hub/utils"
 	"github.com/getAlby/hub/version"
-	"github.com/nbd-wtf/go-nostr"
 )
 
 type api struct {
@@ -81,7 +79,9 @@ func (api *api) CreateApp(ctx context.Context, createAppRequest *CreateAppReques
 		expiresAt,
 		createAppRequest.Scopes,
 		createAppRequest.Isolated,
-		createAppRequest.Metadata)
+		createAppRequest.Metadata,
+		api.svc.GetKeys().GetBIP32ChildKey,
+	)
 
 	if err != nil {
 		return nil, err
@@ -100,21 +100,12 @@ func (api *api) CreateApp(ctx context.Context, createAppRequest *CreateAppReques
 		return nil, err
 	}
 
-	appWalletKey, err := api.keys.GetBIP32ChildKey(uint32(app.ID))
-	if err != nil {
-		fmt.Println("error creating child key: ", err)
-		return nil, err
-	}
-	fmt.Println("!+!+!+!+!+!+!+ app secret key: ", hex.EncodeToString(appWalletKey.Serialize()))
-	appWalletPubKey, _ := nostr.GetPublicKey(hex.EncodeToString(appWalletKey.Serialize()))
-	fmt.Println("!+!+!+!+!+!+!+ app public key: ", appWalletPubKey)
-
 	if createAppRequest.ReturnTo != "" {
 		returnToUrl, err := url.Parse(createAppRequest.ReturnTo)
 		if err == nil {
 			query := returnToUrl.Query()
 			query.Add("relay", relayUrl)
-			query.Add("pubkey", appWalletPubKey)
+			query.Add("pubkey", app.WalletChildPubkey)
 			if lightningAddress != "" && !app.Isolated {
 				query.Add("lud16", lightningAddress)
 			}
@@ -127,14 +118,7 @@ func (api *api) CreateApp(ctx context.Context, createAppRequest *CreateAppReques
 	if lightningAddress != "" && !app.Isolated {
 		lud16 = fmt.Sprintf("&lud16=%s", lightningAddress)
 	}
-	responseBody.PairingUri = fmt.Sprintf("nostr+walletconnect://%s?relay=%s&secret=%s%s", appWalletPubKey, relayUrl, pairingSecretKey, lud16)
-
-	fmt.Println("~+~+~+~+~+~+~+~+~+ GOING TO SUBSCRIBE TO NEW APP WALLET!!!!!!!!!!!!!! ")
-	err = api.svc.SubscribeToAppRequests(ctx, appWalletPubKey)
-	if err != nil {
-		fmt.Println("error subscribing to new app wallet key: ", err)
-		return nil, err
-	}
+	responseBody.PairingUri = fmt.Sprintf("nostr+walletconnect://%s?relay=%s&secret=%s%s", app.WalletChildPubkey, relayUrl, pairingSecretKey, lud16)
 
 	return responseBody, nil
 }
@@ -234,7 +218,7 @@ func (api *api) UpdateApp(userApp *db.App, updateAppRequest *UpdateAppRequest) e
 }
 
 func (api *api) DeleteApp(userApp *db.App) error {
-	return api.db.Delete(userApp).Error
+	return api.dbSvc.DeleteApp(userApp)
 }
 
 func (api *api) GetApp(dbApp *db.App) *App {

db/db_service.go

@@ -28,7 +28,17 @@ func NewDBService(db *gorm.DB, eventPublisher events.EventPublisher) *dbService
 	}
 }
 
-func (svc *dbService) CreateApp(name string, pubkey string, maxAmountSat uint64, budgetRenewal string, expiresAt *time.Time, scopes []string, isolated bool, metadata map[string]interface{}) (*App, string, error) {
+func (svc *dbService) CreateApp(
+	name string,
+	pubkey string,
+	maxAmountSat uint64,
+	budgetRenewal string,
+	expiresAt *time.Time,
+	scopes []string,
+	isolated bool,
+	metadata map[string]interface{},
+	walletChildPrivKeyGeneratorFunc func(appId uint32) (string, error),
+) (*App, string, error) {
 	if isolated && (slices.Contains(scopes, constants.SIGN_MESSAGE_SCOPE)) {
 		// cannot sign messages because the isolated app is a custodial subaccount
 		return nil, "", errors.New("isolated app cannot have sign_message scope")
@@ -59,7 +69,7 @@ func (svc *dbService) CreateApp(name string, pubkey string, maxAmountSat uint64,
 		}
 	}
 
-	app := App{Name: name, NostrPubkey: pairingPublicKey, walletChildIdx: 2, Isolated: isolated, Metadata: datatypes.JSON(metadataBytes)}
+	app := App{Name: name, NostrPubkey: pairingPublicKey, Isolated: isolated, Metadata: datatypes.JSON(metadataBytes)}
 
 	err := svc.db.Transaction(func(tx *gorm.DB) error {
 		err := tx.Save(&app).Error
@@ -82,6 +92,21 @@ func (svc *dbService) CreateApp(name string, pubkey string, maxAmountSat uint64,
 			}
 		}
 
+		appWalletChildPrivKey, err := walletChildPrivKeyGeneratorFunc(uint32(app.ID))
+		if err != nil {
+			return fmt.Errorf("error generating wallet child private key: %w", err)
+		}
+
+		app.WalletChildPubkey, err = nostr.GetPublicKey(appWalletChildPrivKey)
+		if err != nil {
+			return fmt.Errorf("error generating wallet child public key: %w", err)
+		}
+
+		err = tx.Model(&App{}).Where("id", app.ID).Update("wallet_child_pubkey", app.WalletChildPubkey).Error
+		if err != nil {
+			return err
+		}
+
 		// commit transaction
 		return nil
 	})
@@ -94,9 +119,28 @@ func (svc *dbService) CreateApp(name string, pubkey string, maxAmountSat uint64,
 	svc.eventPublisher.Publish(&events.Event{
 		Event: "app_created",
 		Properties: map[string]interface{}{
-			"name": name,
+			"name":              name,
+			"id":                app.ID,
+			"walletChildPubkey": app.WalletChildPubkey,
 		},
 	})
 
 	return &app, pairingSecretKey, nil
 }
+
+func (svc *dbService) DeleteApp(app *App) error {
+
+	err := svc.db.Delete(app).Error
+	if err != nil {
+		return err
+	}
+	svc.eventPublisher.Publish(&events.Event{
+		Event: "app_deleted",
+		Properties: map[string]interface{}{
+			"name":              app.Name,
+			"id":                app.ID,
+			"walletChildPubkey": app.WalletChildPubkey,
+		},
+	})
+	return nil
+}

db/migrations/202410141503_wallet_child_idx.go → db/migrations/202410141503_wallet_child_pubkey.go

@@ -7,13 +7,12 @@ import (
 	"gorm.io/gorm"
 )
 
-var _202410141503_wallet_child_idx = &gormigrate.Migration{
-	ID: "202410141503_wallet_child_idx",
+var _202410141503_wallet_child_pubkey = &gormigrate.Migration{
+	ID: "202410141503_wallet_child_pubkey",
 	Migrate: func(tx *gorm.DB) error {
 
 		if err := tx.Exec(`
-	ALTER TABLE apps ADD COLUMN wallet_child_idx INTEGER;
-	CREATE UNIQUE INDEX idx_wallet_child_idx ON apps (wallet_child_idx);
+	ALTER TABLE apps ADD COLUMN wallet_child_pubkey TEXT;
 `).Error; err != nil {
 			return err
 		}

db/migrations/migrate.go

@@ -22,7 +22,7 @@ func Migrate(gormDB *gorm.DB) error {
 		_202408061737_add_boostagrams_and_use_json,
 		_202408191242_transaction_failure_reason,
 		_202408291715_app_metadata,
-		_202410141503_wallet_child_idx,
+		_202410141503_wallet_child_pubkey,
 	})
 
 	return m.Migrate()

db/models.go

@@ -16,15 +16,15 @@ type UserConfig struct {
 }
 
 type App struct {
-	ID             uint
-	Name           string `validate:"required"`
-	Description    string
-	NostrPubkey    string `validate:"required"`
-	walletChildIdx uint   `validate:"required"`
-	CreatedAt      time.Time
-	UpdatedAt      time.Time
-	Isolated       bool
-	Metadata       datatypes.JSON
+	ID                uint
+	Name              string `validate:"required"`
+	Description       string
+	NostrPubkey       string `validate:"required"`
+	WalletChildPubkey string
+	CreatedAt         time.Time
+	UpdatedAt         time.Time
+	Isolated          bool
+	Metadata          datatypes.JSON
 }
 
 type AppPermission struct {
@@ -88,7 +88,8 @@ type Transaction struct {
 }
 
 type DBService interface {
-	CreateApp(name string, pubkey string, maxAmountSat uint64, budgetRenewal string, expiresAt *time.Time, scopes []string, isolated bool, metadata map[string]interface{}) (*App, string, error)
+	CreateApp(name string, pubkey string, maxAmountSat uint64, budgetRenewal string, expiresAt *time.Time, scopes []string, isolated bool, metadata map[string]interface{}, walletChildPrivKeyGeneratorFunc func(uint32) (string, error)) (*App, string, error)
+	DeleteApp(app *App) error
 }
 
 const (

nip47/event_handler.go

@@ -2,7 +2,6 @@ package nip47
 
 import (
 	"context"
-	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -46,6 +45,33 @@ func (svc *nip47Service) HandleEvent(ctx context.Context, relay nostrmodels.Rela
 		}).Error("invalid event signature")
 		return
 	}
+	pTag := event.Tags.GetFirst([]string{"p"})
+	if pTag == nil {
+		logger.Logger.WithFields(logrus.Fields{
+			"requestEventNostrId": event.ID,
+			"eventKind":           event.Kind,
+		}).Error("invalid event, missing p tag")
+		return
+	}
+	appWalletPubKey := pTag.Value()
+
+	app := db.App{}
+	err = svc.db.First(&app, &db.App{
+		NostrPubkey: event.PubKey,
+	}).Error
+
+	appWalletPrivKey := svc.keys.GetNostrSecretKey()
+
+	if appWalletPubKey != svc.keys.GetNostrPublicKey() {
+		// This is a new child key derived from master using app ID as index
+		appWalletPrivKey, err = svc.keys.GetBIP32ChildKey(uint32(app.ID))
+		if err != nil {
+			logger.Logger.WithFields(logrus.Fields{
+				"appId": app.ID,
+			}).WithError(err).Error("error deriving child key")
+			return
+		}
+	}
 
 	ss, err := nip04.ComputeSharedSecret(event.PubKey, svc.keys.GetNostrSecretKey())
 	if err != nil {
@@ -87,12 +113,6 @@ func (svc *nip47Service) HandleEvent(ctx context.Context, relay nostrmodels.Rela
 		return
 	}
 
-	app := db.App{}
-
-	err = svc.db.First(&app, &db.App{
-		NostrPubkey: event.PubKey,
-	}).Error
-
 	if err != nil {
 		logger.Logger.WithFields(logrus.Fields{
 			"nostrPubkey": event.PubKey,
@@ -162,15 +182,6 @@ func (svc *nip47Service) HandleEvent(ctx context.Context, relay nostrmodels.Rela
 		"appId":               app.ID,
 	}).Debug("App found for nostr event")
 
-	appWalletPrivKeyBip32, err := svc.keys.GetBIP32ChildKey(uint32(app.ID))
-	if err != nil {
-		logger.Logger.WithFields(logrus.Fields{
-			"appId": app.ID,
-		}).WithError(err).Error("error deriving child key")
-		return
-	}
-	appWalletPrivKey, _ := nostr.GetPublicKey(hex.EncodeToString(appWalletPrivKeyBip32.Serialize()))
-
 	//to be extra safe, decrypt using the key found from the app
 	ss, err = nip04.ComputeSharedSecret(app.NostrPubkey, appWalletPrivKey)
 	if err != nil {
@@ -368,7 +379,7 @@ func (svc *nip47Service) HandleEvent(ctx context.Context, relay nostrmodels.Rela
 	}
 }
 
-func (svc *nip47Service) CreateResponse(initialEvent *nostr.Event, content interface{}, tags nostr.Tags, ss []byte, walletPrivKey string) (result *nostr.Event, err error) {
+func (svc *nip47Service) CreateResponse(initialEvent *nostr.Event, content interface{}, tags nostr.Tags, ss []byte, appWalletPrivKey string) (result *nostr.Event, err error) {
 	payloadBytes, err := json.Marshal(content)
 	if err != nil {
 		return nil, err
@@ -381,7 +392,7 @@ func (svc *nip47Service) CreateResponse(initialEvent *nostr.Event, content inter
 	allTags := nostr.Tags{[]string{"p", initialEvent.PubKey}, []string{"e", initialEvent.ID}}
 	allTags = append(allTags, tags...)
 
-	appWalletPubKey, _ := nostr.GetPublicKey(walletPrivKey)
+	appWalletPubKey, _ := nostr.GetPublicKey(appWalletPrivKey)
 
 	resp := &nostr.Event{
 		PubKey:    appWalletPubKey,
@@ -390,7 +401,7 @@ func (svc *nip47Service) CreateResponse(initialEvent *nostr.Event, content inter
 		Tags:      allTags,
 		Content:   msg,
 	}
-	err = resp.Sign(walletPrivKey)
+	err = resp.Sign(appWalletPrivKey)
 	if err != nil {
 		return nil, err
 	}

nip47/nip47_service.go

@@ -2,7 +2,6 @@ package nip47
 
 import (
 	"context"
-
 	"github.com/getAlby/hub/config"
 	"github.com/getAlby/hub/events"
 	"github.com/getAlby/hub/lnclient"
@@ -29,7 +28,8 @@ 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)
-	PublishNip47Info(ctx context.Context, relay nostrmodels.Relay, lnClient lnclient.LNClient) 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

@@ -2,7 +2,6 @@ package notifications
 
 import (
 	"context"
-	"encoding/hex"
 	"encoding/json"
 
 	"github.com/getAlby/hub/config"
@@ -109,15 +108,14 @@ func (notifier *Nip47Notifier) notifySubscriber(ctx context.Context, app *db.App
 		"appId":        app.ID,
 	}).Debug("Notifying subscriber")
 
-	appWalletPrivKeyBIP32, err := notifier.keys.GetBIP32ChildKey(uint32(app.ID))
+	appWalletPrivKey, err := notifier.keys.GetBIP32ChildKey(uint32(app.ID))
 	if err != nil {
 		logger.Logger.WithFields(logrus.Fields{
 			"notification": notification,
 			"appId":        app.ID,
 		}).WithError(err).Error("error derivingchild key")
 		return
 	}
-	appWalletPrivKey := hex.EncodeToString(appWalletPrivKeyBIP32.Serialize())
 
 	ss, err := nip04.ComputeSharedSecret(app.NostrPubkey, appWalletPrivKey)
 	if err != nil {