反序列化 HttpResponseMessage

Question

I have an API (asp net core 3.1) and a web application (asp net Blazor WebAssembly). In my API I have a CustomerController with the following method for POST:

    [HttpPost]
    public async
        Task<ActionResult>
        CreateOrderAsync(OrderDto orderDto)
    {
        orderDto.IdOrder =
            await repository
            .CreateOrderAsync(mapper.Map<Order>(orderDto));
        return CreatedAtRoute(nameof(GetOrderByIdAsync),
            new { idOrder = orderDto.IdOrder }, orderDto);
    }

In my web application I have the class DataServiceHelper, which I use in the actual data services for the web app. Here I have methods for POST and GET and so on:

  ...
  static public async Task PostAsync(HttpClient httpClient, string endpoint, T item)
  {
     await httpClient.PostAsJsonAsync(endpoint, item);
  }
  static public async Task<T> FindOneByIdAsync(HttpClient httpClient, string endpoint)
  {
      return await JsonSerializer.DeserializeAsync<T>
         (await httpClient.GetStreamAsync(endpoint), new JsonSerializerOptions()
         { ropertyNameCaseInsensitive = true });
  }
  ...

If I send a POST request to the API (say via Postman) the response contains (among others) the body, which is a jsonized version of my database object. Can I somehow catch that body in my Web App with JsonSerializer and return it like I do with my FindOneByIdAsync method? Alternatively, in the API, could I create a new header in the responses headers that only contains the Id, that the database creates for the new object, and catch that in my web apps post method from the response?

Answer 1

Might be a little cumbersome, but this works:

static public async Task<T>PostAndListenAsync(HttpClient httpClient, string endpoint, T item)
{            
    var content = await httpClient.PostAsJsonAsync(endpoint, item);
    var stream = await content.Content.ReadAsStreamAsync();
    T t = await JsonSerializer.DeserializeAsync<T>(stream, new JsonSerializerOptions() { PropertyNameCaseInsensitive = true });
    return t;
}

Feel free to make a neat one-liner out of it.

My Data Service:

public async Task<OrderDto> PostOrderAsync(OrderDto orderDto)
{
    return await DataServiceHelper<OrderDto>.PostAndListenAsync(httpClient, "/Orders", orderDto);
}

In razor:

...
private async Task CreateNewOrder()
{
        OrderDto orderDto = await dataService.PostOrderAsync(newOrder);
}
...

Answer 2

Use System.Net.Http.Json . Examples:

Task<O> CallGet<O>(string requestUrl) => http.GetFromJsonAsync<O>(requestUrl);

async Task<O> CallPost<I, O>(string requestUrl, I input)
{
    using var response = await http.PostAsJsonAsync(requestUrl, input);
    return await response.Content.ReadFromJsonAsync<O>();
}

See the documentation for more methods and overloads.

It is available also as a nuget: https://www.nuget.org/packages/System.Net.Http.Json