public async Task <IActionResult> Create([Bind("Id,Name,Price,CreateTime,Store")] Product product)
        {
            if (ModelState.IsValid)
            {
                _context.Add(product);
                await _context.SaveChangesAsync();

                //notify
                FirebaseNotification noti = new FirebaseNotification();
                DataMessage          data = new DataMessage()
                {
                    Data            = product,
                    RegistrationIds = new List <string>()
                    {
                        androidDeviceToken, webDeviceToken
                    },
                    notification = new Notification()
                    {
                        title = product.Name,
                        text  = "Name: " + product.Name + "\nPrice: " + product.Price + "\nStore: " + product.Store
                    }
                };
                await noti.SendMessage(data);

                return(RedirectToAction(nameof(Index)));
            }
            return(View(product));
        }
        public async Task <string> Notify(int?id)
        {
            var product = await _context.Product
                          .FirstOrDefaultAsync(m => m.Id == id);

            FirebaseNotification noti = new FirebaseNotification();
            DataMessage          data = new DataMessage()
            {
                Data            = product,
                RegistrationIds = new List <string>()
                {
                    androidDeviceToken, webDeviceToken
                },
                notification = new Notification()
                {
                    title = product.Name,
                    text  = "Name: " + product.Name + "\nPrice: " + product.Price + "\nStore: " + product.Store
                }
            };
            string result = await noti.SendMessage(data);

            return(result);
        }