public async Task <IActionResult> AddItemToCart(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)]
HttpRequestMessage req, ILogger log)
{
string jsonContent = await req.Content.ReadAsStringAsync();
if (string.IsNullOrEmpty(jsonContent))
{
return(new BadRequestErrorMessageResult("Invalid input."));
}
CartItem cartItem = JsonConvert.DeserializeObject <CartItem>(jsonContent);
return(new OkObjectResult(await _checkoutService.AddItemToCart(cartItem)));
}