ASP.NET WEB API not binding to dynamic object on POST

Question

If have the following Api Controller ... using StrutureMap for the DI ...

using System;
using System.Dynamic;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using IdentityService.Domain;
using IdentityService.Domain.Contracts;
using IdentityService.Domain.Models;

namespace IdentityService.Controllers
{
    public class AccountController : ApiController
    {
        private readonly IRepository<Client> _clientRepository;
        private readonly IRepository<RelyingParty> _relyingPartyRepository;
        private readonly IRepository<Token> _tokenRepository;

        public AccountController(
            IRepository<Client> clientRepository,
            IRepository<RelyingParty> relyingPartyRepository,
            IRepository<Token> tokenRepository)
        {
            _clientRepository = clientRepository;
            _relyingPartyRepository = relyingPartyRepository;
            _tokenRepository = tokenRepository;
        }

        public HttpResponseMessage Post(
            [FromBody] dynamic data)
        {
            dynamic result = new ExpandoObject();

            try
            {
                var clientAuthenticator = new ClientAuthenticator(
                    _clientRepository,
                    _relyingPartyRepository,
                    _tokenRepository);

                Token token;
                clientAuthenticator.Authenticate(
                    data.Key,
                    data.ChecksumValue,
                    data.Checksum,
                    data.Name,
                    data.Password,
                    out token);

                result.Token = token;
            }
            catch (Exception ex)
            {
                result.ErrorCode = ex.GetType().ToString();
                result.ErrorMessage = ex.GetBaseException().Message;
            }

            return this.Request.CreateResponse(HttpStatusCode.OK, (ExpandoObject)result);
        }
    }
}

Using Fiddler, I am make the following post:

POST http://localhost:54029/api/account HTTP/1.1
User-Agent: Fiddler
Host: localhost:54029
Content-Type: "application/json"
Content-Length: 218

{
    "Key": "7d42276d3c3954716c672543385b575836472f5d543d7776205627413a",
    "ChecksumValue": "127.0.0.1",
    "Checksum": "ao4Ei77BaX1/iMZMTAJxWzt4fxc=",
    "Name": "USER_NAME",
    "Password": "PASSWORD"
}

Any idea why my data would be null? I have tried switching to JObject, with no success. All the examples I have found makes me think this should work.

Here is the complete response:

HTTP/1.1 200 OK
Cache-Control: no-cache
Pragma: no-cache
Content-Type: application/json; charset=utf-8
Expires: -1
Server: Microsoft-IIS/8.0
X-AspNet-Version: 4.0.30319
X-SourceFiles: =?UTF-8?B?QzpcY29kZS1tYXR0cnVtYVx0YWxrLWF1dGhlbnRpY2F0aW9uLXNlcnZlclxJZGVudGl0eVNlcnZpY2VcYXBpXGFjY291bnQ=?=
X-Powered-By: ASP.NET
Date: Mon, 27 May 2013 13:59:45 GMT
Content-Length: 137

{"ErrorCode":"Microsoft.CSharp.RuntimeBinder.RuntimeBinderException","ErrorMessage":"Cannot perform runtime binding on a null reference"}

Any help would be much appreciated!

Update

I tried just a simple example, like:

public async Task<dynamic> Post(dynamic data)
{
     var body = await Request.Content.ReadAsStringAsync();

     return data;
}

The parameter data is still null, but I can see the values in body.

Answer 1

Remove the quotes from "application/json".

Content-Type: application/json

Answer 2

In an MVC 6 controller (which extends from Controller and not ApiController) the following does work (with report being JSON) :

    [HttpPost("[action]")]
    public void RunReport([FromBody]dynamic report)
    {
        ....
    }

---

Updated: For MVC 5 this is what I use

    [HttpPost]
    public async Task<HttpResponseMessage> FBLogin(Newtonsoft.Json.Linq.JObject jObject)
    {
        dynamic data = (dynamic)jObject;

        string accessToken = data.accessToken;
        ...
     }

Where the JSON payload is :

 '{accessToken: "EAAJF9eVIKOsBABdKVNOLJyfyCnnkrl8mlW2crgZC1NYsDqgq9ZBIZC......" }'