alby-hub/service/delete_app_consumer.go

package service

import (
	"context"

	"github.com/getAlby/go-nostr"
	"github.com/getAlby/hub/events"
	"github.com/getAlby/hub/logger"
)

type deleteAppConsumer struct {
	events.EventSubscriber
	walletPubkey       string
	pool               *nostr.SimplePool
	cancelSubscription func()
	svc                *service
}

// When an app is deleted, unsubscribe from events for that app on the relay
// and publish a deletion event for that app's info event
func (s *deleteAppConsumer) ConsumeEvent(ctx context.Context, event *events.Event, globalProperties map[string]interface{}) {
	if event.Event != "nwc_app_deleted" {
		return
	}
	properties, ok := event.Properties.(map[string]interface{})
	if !ok {
		logger.Logger.WithField("event", event).Error("Failed to cast event.Properties to map")
		return
	}
	// Note: for legacy apps the deleted app's WalletPubkey is empty and will
	// not match the master key used for the legacy app subscription, so the
	// subscription is preserved for any remaining legacy apps.
	walletPubKey, _ := properties["walletPubkey"].(string)
	if walletPubKey == "" || walletPubKey != s.walletPubkey {
		return
	}
	id, ok := properties["id"].(uint)
	if !ok {
		logger.Logger.WithField("event", event).Error("missing id in properties event")
		return
	}

	// no longer need to listen to events for this wallet
	s.cancelSubscription()

	// remove this consumer as subscriber in eventPublisher
	s.svc.eventPublisher.RemoveSubscriber(s)

	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
	}

	// try to delete info event from relays (non-critical if it fails)
	// get nip47 event info for this app wallet key
	nip47InfoEvent, err := s.svc.GetNip47Service().GetNip47Info(ctx, s.pool, s.walletPubkey)
	if err != nil {
		logger.Logger.WithError(err).Error("Could not get nip47 info event")
		return
	}
	if nip47InfoEvent != nil {
		err = s.svc.nip47Service.PublishNip47InfoDeletion(ctx, s.pool, walletPubKey, walletPrivKey, nip47InfoEvent.ID)
		if err != nil {
			logger.Logger.WithError(err).WithField("event", event).Error("Failed to publish nip47 info deletion")
		}
	}
}