I've been struggling a lot with that, I found some questions but none could answer my needs. I will try to post a better question and some of the things I tried.
Here is the situation: I have an APIGateway and a WebApp. The WebApp sends POST requests to the APIGateway, so far so good. I use the FromBody attribute to send larger objects, and that was fine too until I introduced interfaces :))
Here's some code:
WebApp:
public interface ICommand
{
Guid CorrelationId { get; set; }
Guid SocketId { get; set; }
}
public class Command : ICommand
{
public Command(Guid CorrelationId, Guid SocketId)
{
this.CorrelationId = CorrelationId;
this.SocketId = SocketId;
}
public Guid CorrelationId { get; set; } = new Guid();
public Guid SocketId { get; set; } = new Guid();
}
public interface IDocument
{
Guid Id { get; set; }
ulong Number { get; set; }
}
public class Document : IDocument
{
public Guid Id { get; set; } = new Guid();
public ulong Number { get; set; } = 0;
}
public interface ICreateDocumentCommand : ICommand
{
IDocument Document { get; set; }
}
public class CreateDocumentCommand : Command, ICreateDocumentCommand
{
public CreateDocumentCommand(IDocument Document, ICommand Command) : base(Command.CorrelationId, Command.SocketId)
{
this.Document = Document;
}
public IDocument Document { get; set; }
}
APIGateway:
[HttpPost]
public async Task<IActionResult> Create([FromBody]CreateDocumentCommand documentCommand)
{
if (documentCommand == null)
{
return StatusCode(403);
}
return Json(documentCommand.Document.Id);
}
Use case:
public class InventoryList : Document
{
public Guid WarehouseId { get; set; } = new Guid();
}
// Example document class
////////////////////////////////////////
// Example POST Request
ICommand command = new Command(messageId, socketId);
switch (item.GetType().Name)
{
case "InventoryList":
command = new CreateDocumentCommand((InventoryList)item, command);
break;
}
string result = await PostAsync($"{apiGatewayAddress}{item.GetType().BaseType.Name}/Create", command, accessToken);
My POST sending function:
public async Task<string> PostAsync<T>(string uri, T item, string authorizationToken = null, string authorizationMethod = "Bearer")
{
JsonSerializerSettings jsonSerializerSettings = new JsonSerializerSettings { TypeNameHandling = TypeNameHandling.All };
HttpRequestMessage requestMessage = new HttpRequestMessage(HttpMethod.Post, uri);
requestMessage.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
requestMessage.Content = new StringContent(JsonConvert.SerializeObject(item, typeof(T), jsonSerializerSettings), System.Text.Encoding.UTF8, "application/json");
return await _client.SendAsync(requestMessage).Result.Content.ReadAsStringAsync();
}
As you can see I have included TypeNameHandling.All in the JSON serialization settings, the request is sent and the Create in the APIGateway gets called. However the parameter documentCommand is NULL.
I've read this: Asp.Net Core Post FromBody Always Null
This: Casting interfaces for deserialization in JSON.NET
Tried all kind of magic tricks, created new constructors, marked them with [JSONConstructor], still no success. Also I tried changing the APIGateway Cerate method parameter type to ICreateDocumentCommand and again I got a null. I've been searching some model binding tricks online however I couldn't find anything for binding with FromBody. I also found some solution including DI but I am looking for a simple solution. I hope that we will be able to find one :)
