func main() { ctx := context.Background() client, err := datastore.NewClient(ctx, "my-project") if err != nil { log.Fatal(err) } defer client.Close() bookRepository := NewBookRepository(client) bookOwnershipRepository := NewBookOwnershipRepository(client) userRepository := NewUserRepository(client) notificationRepository := NewNotificationRepository(client) bookshelfService := NewBookshelfService(